ML16067A151

EP-AA-1011, Addendum 3, Revision 1, Calvert Cliffs Nuclear Power Plan Emergency Action Levels, - Emergency Plan Addendum

ML16067A151
Person / Time
Site:	Calvert Cliffs
Issue date:	02/26/2016
From:	Exelon Generation Co
To:	Office of Nuclear Material Safety and Safeguards
Shared Package
ML16067A147	List: ML16067A148 ML16067A151
References
EP-AA-1011, Rev. 1, Addendum 3
Download: ML16067A151 (284)

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ATTACHMENT 3EP-AA-1011, Addendum 3, Revision 1, "Calvert Cliffs Nuclear PowerPlant Emergency Action Levels"Emergency Plan AddendumExelon Confidential/Proprietary InformationWithhold Under 10 CFR 2.390 Exelon Confidential/Proprietary~Exelon Generation°EP-AA-1 011, Addendum 3Revision 1CALVERT CLIFFSNUCLEAR POWER PLANTEMERGENCY ACTION LEVELS Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearTable of ContentsSECTION TITLE PAGE1.0 PURPOSE ........................................................................... 102.0 DISCUSSION ........................................................................ 102.1 Background .................................................................. 102.2 Fission Product Barriers..................................................... 112.3 Emergency Classification Based on Fission ProductBarrier Degradation ......................................................... 112.4 EAL Relationship to EOPs and Critical Safety Function Status.......... 122.5 Symptom-Based vs. Event-Based Approach ..... ........................ 122.6 EAL Organization............................................................ 132.7 Technical Bases Information................................................ 152.8 Operating Mode Applicability ............................................... 162.9 Validation of Indications, Reports and Conditions ........................ 172.10 Planned vs. Unplanned Events............................................. 182.11 Classifying Transient Events ........................................... 2.12 Multiple Simultaneous Events and Imminent EAL Thresholds........... 192.13 Emergency Classification Level Downgrading ............................ 1

93.0 REFERENCES

....................................................................... 203.1 Developmental............................................................... 203.2 Implementing ................................................................ 203.3 Commitments................................................................. 204.0 DEFINITIONS........................................................................ 215.0 CCNPP-TO-NEI 99-01 EAL CROSS REFERENCE .............................. 256.0 ATTACHMENTS..................................................................... 296.1 Attachment 1 -Emergency Action Level Technical Bases....................... 30Cate~qory R Abnormal Rad Levels / Rad Effluents ............................. 30RU1.1 ................................................................ 31RU1.2 ................................................................ 36RAI.1 ..................................... '........................... 38RA1.2 ................................................................ 41RSI.1 ................................................................ 43RS1.2 ................................................................ 47RS1.3 ................................................................ 49RGI.1................................................................ 51February 2016 2 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearTable of ContentsSECTION TITLECategqory RCategqory ECategqory CFebruary 2016PAGE(cont'd)RG1.2................................................................ 56RG1.3................................................................ 58RU2.1 ................................................................ 60RU2.2 ................................................................ 63RA2.1 ................................................................ 64RA2.2 ................................................................ 66RA3.1 ................................................................ 68ISFSI/DSC ........................................................... 69EU1.1 ................................................................ 70Cold Shutdown / Refueling System Malfunction.................. 71CUI.1 ................................................................ 73CA1.1 ................................................................ 76CU2.1 ................................................................ 79CU3.1 ................................................................ 81CU3.2 ................................................................ 83CU3.3 ................................................................ 86CA3.1 ................................................................. 88CS3.1 ................................................................ 92CS3.2 ................................................................ 95CS3.3................................................................ 98CG3.1............................................................... 102CG3.2 .............................................................. 106CU4.1 ............................................................... 111CU4.2 ............................................................... 113CA4.1 ............................................................... 115CU5.1 ............................................................... 118CU6.1 ............................................................... 1203EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvedt CliffsAnnexExelon NuclearSECTION TITLECateciory HCategory SFebruary 2016Table of ContentsPAGEHazards and Other Conditions Affecting Plant Safety.......... 121HU1.1 ............................................................... 123HUI.2 ............................................................... 125HUI.3 ............................................................... 126HUI.4............................................................... 128HU1.5............................................................... 130HA1.1 ............................................................... 132HAI.2 ............................................................... 135HAI.3 ............................................................... 138HAI.4 ............................................................... 141HA1.5 ............................................................... 144HAI.6 ............................................................... 146HU2.1 ............................................................... 148HU2.2............................................................... 150HA2.1 ............................................................... 152HU3.1 ............................................................... 155HU3.2 ............................................................... 157HA3.1 ............................................................... 158HU4.1 ............................................................... 160HA4.1 ............................................................... 163HS4.1 ............................................................... 165HG4.1............................................................... 167HG4.2 .............................................................. 169HA5.1 ............................................................... 170HS5.1 ............................................................... 171HU6.1 ............................................................... 173HA6.1 ............................................................... 174HS6.1 ............................................................... 176HG6.1 .............................................................. 178System Malfunction ............................................... 180SUI.1............................................................... 182SAI.1............................................................... 184SSI.1............................................................... 187SGI.1............................................................... 190SS2.1............................................................... 1944EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearTable of ContentsSECTION TITLE PAGESU3.1 ............................................................... 196SA3.1 ............................................................... 197SS3.1 ............................................................... 200SG3.1 ............................................................... 203SU4.1 ............................................................... 207SU5.1 ............................................................... 208SA5.1 ............................................................... 211SS5.1 ............................................................... 214SU6.1 ............................................................... 217SU7.1 ............................................................... 219SU7.2............................................................... 221SU8.1 ............................................................... 222Category F Fission Product Barrier Degradation ............................. 224FUI.1 ............................................................... 226FAI.1 ............................................................... 227FSI.1 ............................................................... 228FGI.1 ............................................................... 2296.2 Attachment 2 -Fission Product Barrier Loss / Potential LossMatrix and Bases................................................................... 230FC Loss A.1........................................................ 233FC Potential Loss A.1 ............................................. 234FC Potential Loss A.2 ............................................. 235FC Potential Loss B.3 ............................................. 238FC Loss C.2........................................................ 239FC Loss C.3........................................................ 240FC Loss C.4........................................................ 241FC Loss E.5........................................................ 245FC Potential Loss E.4 ............................................. 246RCS Potential Loss A.1 ........................................... 248RCS Potential Loss A.2 ........................................... 249RCS Potential Loss A.3 ........................................... 251RCS Loss B.1...................................................... 252RCS Loss B.2...................................................... 253RCS Potential Loss B.4 ........................................... 254RCS Loss C.3...................................................... 255February 2016 5 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearSECTION6.2Table of ContentsTITLE PAGEAttachment 2 (cont'd)RCS Loss E.4...................................................... 260ROS Potential Loss E.5 ........................................... 261CNMT Potential Loss A.1 ......................................... 263CNMT Potential Loss A.2 ......................................... 265CNMT Loss B.1 .................................................... 267CNMT Loss B.2 .................................................... 268CNMT Loss B.3 .................................................... 269CNMT Loss B.4 .................................................... 270CNMT Potential Loss B.3 ............................... ..........273CNMT Potential Loss B.4 ......................................... 274CNMT Potential Loss B.5 ................................. .........275CNMT Potential Loss C.6 ......................................... 277CNMT Loss D.5.................................................... 279CNMT Loss E.6 .................................................... 281CNMT Potential Loss E.7 ......................................... 282February 20166EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearABBEVIATIONS / ACRONYMSAC .................................................................................... Alternating CurrentAPRM..................................................................... Average Power Range MeterATWS............................................................ Anticipated Transient Without ScramCAC............................................................................. Containment Air CoolerCAS............................................................ '.................... Central Alarm StationCCW ........................................................................ Component Cooling WaterCDE........................................................................ Committed Dose EquivalentCE.............................................................................. Combustion EngineeringCET............................................................................. Core exit ThermocoupleCFR ....................................................................... Code of Federal RegulationsCHRRM.................................................. Containment High Range Radiation MonitorCR .......................................................................................... Control RoomCTMT/CNMT ............................................................................... ContainmentCSF.............................................................................. Critical Safety FunctionCSFST............................................................. Critical Safety Function Status TreeDC ......................................................................................... Direct CurrentDEQ ..................................................................................... Dose EquivalentDHR ............................................................................... Decay Heat RemovalDisch ........................................................................................... DischargeDOT...................................................................... Department of TransportationDSC .............................................................................. Dry Shielded CanisterEAL ............................................................................ Emergency Action LevelECCS................................................................ Emergency Core Cooling SystemECL .................................................................... Emergency Classification LevelED ................................................................................... Emergency DirectorEOF..................................................................... Emergency Operations FacilityEOP.................................................................. Emergency Operating ProcedureEPA.................................................................. Environmental Protection AgencyEPG .................................................................. Emergency Procedure GuidelineEPRI.................................................................. Electric Power Research InstituteERG................................................................... Emergency Response GuidelineEPIP ........................................................ Emergency Plan Implementing ProcedureESF ......................................................................... Engineered Safety FeatureESW ......................................................................... Emergency Service WaterFAA .................................................................... Federal Aviation AdministrationFBI ..................................................................... Federal Bureau of InvestigationFEMA ...................................................... Federal Emergency Management AgencyFebruary 2016 7 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearACRONYMS & ABBREVIATIONS (continued)GE ................................................................................... General EmergencyHOO.......................................................... Headquarters (NRC) Operations OfficerHPSI..................................................................... High Pressure Safety InjectionIC ..................................................................................... Initiating ConditionIM .............................................................................. Instrument MaintenanceIPEEE...................... Individual Plant Examination of External Events (Generic Letter 88-20)ISFSI .................................................... Independent Spent Fuel Storage InstallationKeff............................................................. Effective Neutron Multiplication FactorLCO..................................................................... Limiting Condition of OperationLER ..................................................... '......................... Licensee Event ReportLOCA ......................................................................... Loss of Coolant AccidentLPSI...................................................................... Low Pressure Safety InjectionLWR ................................................................................. Light Water ReactorMSIV........................................................................ Main Steam Isolation ValveMSL ..................................................................................... Main Steam LinemR ......................................................................................... milliRoentgenMW ............................................................................................. MegawattMWS..................................................................... Miscellaneous Waste SystemNEI.............................................................................. Nuclear Energy InstituteNESP ......................................................... National Environmental Studies ProjectNPP ................................................................................ Nuclear Power PlantNRC................................................................... Nuclear Regulatory CommissionNSSS................................................................... Nuclear Steam Supply SystemNORAD .............................................. North American Aerospace Defense CommandNUMARC.............................................. Nuclear Management and Resources CouncilOBE........................................................................ Operating Basis EarthquakeOCA............................................................................. Owner Controlled AreaODCM/ODAM ...................................... Off-site Dose Calculation (Assessment) ManualORO ................................................................... Off-site Response OrganizationOTCC...................................................................... Once Through Core CoolingPA ......................................................................................... Protected AreaPAG......................................................................... Protective Action GuidelinePOAH .............................................................................. Point of Adding HeatPORV.................................................................. Pressure Operated Relief ValvePRA/PSA......................... Probabilistic Risk Assessment / Probabilistic Safety Assessment....................................................................... Pressurized Water ReactorPSIG................................................................... Pounds per Square Inch GaugeFebruary 2016 8 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvedt Cliffs Annex Exelon NuclearACRONYMS & ABBREVIATIONS (continued)R................................................................................................ RoentgenROCC........................................................................... Reactor Control ConsoleRCIC ................................................................... Reactor Core Isolation CoolingRCS............................................................................ Reactor Coolant Systemrem ........................................................................... Roentgen Equivalent ManRETS.................................................. Radiological Effluent Technical SpecificationsRFP ...................................................... .......................... Refueling Pool LevelRPS ......................................................................... Reactor Protection SystemRPV ........................................................................... Reactor Pressure VesselRVLIS ......................................................... Reactor Vessel Level Indicating SystemRWCU .......................................................................... Reactor Water CleanupRWST .................................................................... Reactor Water Storage TankSAE................................................................................ Site Area EmergencySBO ..................................................................................... Station BlackoutSCBA............................................................. Self Contained Breathing ApparatusSG ...................................................................................... Steam GeneratorSI ......................................................................................... Safety InjectionSPOS................................................................ Safety Parameter Display SystemSRO ........................................................................... Senior Reactor OperatorSSE ........................................................................ Safe Shutdown EarthquakeSUR ......................................................................................... Startup RateTEDE.................................................................. Total Effective Dose EquivalentTOAF ................................................................................. Top of Active FuelTSC........................................................................... Technical Support CenterUE ......................................................................................... Unusual EventUFSAR.......................................................... Updated Final Safety Analysis ReportWE ............................................................................... Westinghouse ElectricWOG..................................................................... Westinghouse Owners GroupWRNGM .............................................................. Wide Range Noble Gas MonitorFebruary 2016 9EP-AA-1O11 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclear1.0 PURPOSEThis document provides an explanation and rationale for each Emergency Action Level (EAL)included in the EAL Upgrade Project for Calvert Cliffs Nuclear Power Plant (CCNPP). The EALTechnical Bases Document is intended to provide clarification and understanding of how the EALswere developed for CCNPP as well as the intent of each EAL. This document ensures consistentunderstanding of the EAL scheme for decision makers. It should be used to facilitate review ofthe CCNPP EALs and provide historical documentation for future reference. Decision-makersresponsible for implementation of EAL-TB-HOT or EAL-TB-COLD Emergency Action Level Matrix,may use this document as a technical reference in support of EAL interpretation. This informationmay assist the Emergency Director in making classifications, particularly those involving judgmentor multiple events. The basis information shall also be used in training, for explaining eventclassifications to off-site officials, and facilitates regulatory review and approval of theclassification scheme.The expectation is that emergency classifications are to be made as soon as conditions arepresent and recognizable for the classification, but within 15 minutes in all cases of conditionspresent. Use of this document for assistance is not intended to delay the emergency classification.2.0 DISCUSSION2.1 BackgroundEALs are the plant-specific indications, conditions or instrument readings that are utilized toclassify emergency conditions defined in the CCNPP Emergency Plan.In 1992, the NRC endorsed NUMARC/NESP-007 "Methodology for Development of EmergencyAction Levels" as an alternative to NUREG-0654 EAL guidance.NEI 99-01 (NUMARC/NESP-007) Revision 4 was subsequently issued for industry implementation.Enhancements over earlier revisions included:*Consolidating the system malfunction initiating conditions and example emergency actionlevels which address conditions that may be postulated to occur during plant shutdownconditions.February 2016 10 EP:AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclear* Initiating conditions and example emergency action levels that fully address conditions thatmay be postulated to occur at permanently Defueled Stations and Independent Spent FuelStorage Installations (ISFSIs).* Simplifying the fission product barrier EAL threshold for a Site Area Emergency.Subsequently, Revision 5 of NEI 99-01 has been issued which incorporates resolutions tonumerous implementation issues including the NRC EAL FAQs. Using NEI 99-01 Revision 5 Final(February 2008), CCNPP conducted an EAL implementation upgrade project that produced theEALs discussed herein.2.2 Fission Product BarriersMany of the EALs derived from the NEI methodology are fission product barrier based. That is, theconditions that define the EALs are based upon loss or potential loss of one or more of the threefission product barriers. "Loss" and "Potential Loss" signify the relative damage and threat ofdamage to the barrier. "Loss" means the barrier no longer assures Containment of radioactivematerials; "potential loss" infers an increased probability of barrier loss and decreased certainty ofmaintaining the barrier.The primary fission product barriers are:A. Fuel Clad (FC): The fuel clad barrier consists of fuel bundle tubes composed of zirconium-based alloys that contain the fuel pellets.B. Reactor Coolant System (RCS): The RCS Barrier includes the RCS primary side and itsconnections up to and including the pressurizer safety and relief valves, and otherconnections up to and including the primary isolation valves.C. Containment (CNMT): The Containment Barrier includes the Containment building andconnections up to and including the outermost Containment isolation valves. This barrieralso includes the main steam, feedwater, and blowdown line extensions outside theContainment building up to and including the outermost secondary side isolation valve.2.3 Emergency Classification Based on Fission Product Barrier DegradationThe following criteria are the bases for event classification related to fission product barrier loss orpotential loss:Unusual Event:Any loss or any potential loss of ContainmentFebruary 2016 11 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearAlert:Any loss or any potential loss of either Fuel Clad or RCSSite Area Emerqency:Loss or potential loss of any two barriersGeneral Emerqency:Loss of any two barriers and loss or potential loss of third barrier2.4 EAL Relationship to EOPs and Critical Safety Function StatusWhere possible, the EALs have been made consistent with and utilize the conditions defined in theCCNPP Emergency Operating Procedure (EOP) network. While the symptoms that drive operatoractions specified in the EOPs are not indicative of all possible conditions which warrant emergencyclassification, they define the symptoms, independent of initiating events, for which reactor plantsafety and/or fission product barrier integrity are threatened. When these symptoms are clearlyrepresentative of one of the NEI 99-01 Rev. 5 Initiating Conditions, they have been utilized as anEAL. This permits rapid classification of emergency situations based on plant conditions withoutthe need for additional evaluation or event diagnosis. Although some of the EALs presented hereare based on conditions defined in the EOPs, classification of emergencies using these EALs isnot dependent upon EOP entry or execution. The EALs can be utilized independently or inconjunction with the EOPs.2.5 Symptom-Based vs. Event-Based ApproachTo the extent possible, the EALs are symptom-based. That is, the action level threshold is definedby values of key plant operating parameters that identify emergency or potential emergencyconditions. This approach is appropriate because it allows the full scope of variations in the typesof events to be classified as emergencies. However, a purely symptom-based approach is notsufficient to address all events for which emergency classification is appropriate. Particular eventsto which no predetermined symptoms can be ascribed have also been utilized as EALs since theymay be indicative of potentially more serious conditions not yet fully realized.February 2016 12 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclear2.6 EAL OrganizationThe CCNPP EAL scheme includes the following features:*Division of the EAL set into three broad groups:o EALs applicable under all plant operating modes -This group would be reviewed bythe EAL-user any time emergency classification is considered.oEALs applicable only under hot operating modes -This group would only bereviewed by the EAL-user when the plant is in Hot Shutdown, Hot Standby, Startup,or Power Operation mode.oEALs applicable only under cold operating modes -This group would only bereViewed by the EAL-user when the plant is in Cold Shutdown, Refueling orDefueled mode.The purpose of the groups is to avoid review of hot condition EALs when the plant is in acold condition and avoid review of cold condition EALs when the plant is in a hot condition.This approach significantly minimizes the total number of EALs that must be reviewed bythe EAL-user for a given plant condition, reduces EAL-user reading burden and, thereby,speeds identification of the EAL that applies to the emergency.o Within each of the above three groups, assignment of EALs tocategories/subcategories -Category and subcategory titles are selected torepresent conditions that are operationally significant to the EAL-user.Subcategories are used as necessary to further divide the EALs of a category intological sets of possible emergency classification thresholds. The CCNPP EALcategories/subcategories and their relationship to NEI 99-01 Rev. 5 RecognitionCategories are listed below.February 2016 13 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearEAL Groups, Categories and SubcategoriesELGroup/Category EAL SubcategoryAny Operatinp Mode:R -Abnormal Rad Release / Rad Effluent 1 -Offsite Rad Conditions2 -Onsite Rad Conditions & Spent Fuel Events3 -CR/CAS RadH -Hazards and Other Conditions 1 -Natural or Destructive PhenomenaAffecting Plant Safety 2 -Fire or Explosion3 -Hazardous Gas4 -Security5 -Control Room Evacuation6 -JudgmentNoneE -ISFSI/DSCHot Conditions:S -System Malfunction 1 -Loss of AC Power2 -Loss of DC Power3 -Criticality & RPS Failure4 -Inability to Reach or Maintain Shutdown Conditions5 -Instrumentation6 -Communications7 -Fuel Clad Degradation8 -RCS LeakageF -Fission Product Barrier Degradation NoneCold Conditions:C -Cold Shutdown / Refueling System 1 -Loss of AC PowerMalfunction 2 -Loss of DC Power3 -RCS Level4 -RCS Temperature5 -Communications6 -Inadvertent CriticalityFebruary 201614EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearThe primary tool for determining the emergency classification level is the EAL Classification Matrix.The user of the EAL Classification Matrix may (but is not required to) consult the EAL TechnicalBases Document in order to obtain additional information concerning the EALs under classificationconsideration. The user should consult Sections 2.7 and 2.8, and Attachments 1 and 2 of thisdocument for such information.2.7 Technical Bases InformationEAL technical bases are provided in Attachment 1 for each EAL according to EAL group (Any, Hot,Cold), EAL category (R, E, C, H, S and F) and EAL subcategory. A summary explanation of eachcategory and subcategory is given at the beginning of the technical bases discussions of the EALsincluded in the category. For each EAL, the following information is provided:Cateqory Letter & TitleSubcateqory Number & TitleInitiatinq Condition (IC)Site-specific description of the generic IC given in NEI 99-01 Rev. 5.EAL Identifier (enclosed in rectanqle)Each EAL is assigned a unique identifier to support accurate communication of the emergencyclassification to onsite and offsite personnel. Four characters define each EAL identifier:1. First character (letter): Corresponds to the EAL category as described above (R, E, C,H, S or F)2. Second character (letter): The emergency classification (G, S, A or U)G = General EmergencyS = Site Area EmergencyA = AlertU = Unusual Event3. Third character (number): Subcategory number within the given category.Subcategories are sequentially numbered beginning with the number one (1). If acategory does not have a subcategory, this character is assigned the number one (1).4. Fourth character (number): The numerical sequence of the EAL within the EALsubcategory. If the subcategory has only one EAL, it is given the number one (1).classification (enclosed in rectangqle):Unusual Event (U), Alert (A), Site Area Emergency (S) or General Emergency (G)February 2016 15 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearEAL (enclosed in rectanqle)Wording of the EAL as it appears in the EAL Classification Matrix. Note that defined terms arepresented in all uppercase letters within the EAL wording.Mode ApplicabilityOne or more of the following plant operating conditions comprise the mode to which each EALis applicable: 1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot Shutdown, 5 -ColdShutdown, 6 -Refuel, D -Defueled, or All. (See Section 2.8 for operating mode definitions.)Basis:A Generic basis section provides a description of the rationale for the EAL as PrOvided in NEI99-01 Rev. 5. This is followed by a Plant-Specific basis section that provides CCNPP-relevantinformation concerning the EAL. If the EAL wording contains a defined term, the definition ofthe term is included at the end of the plant-specific basis discussion.CCNPP Basis Reference(s):Site-specific source documentation from which the EAL is derived2.8 Operating Mode Applicability (Technical Specifications Table 1.2)IPower OperationsReactor shutdown margin is less than Technical Specification minimum required (kerr >_0.99) and greater than 5% rated thermal power.February 201616EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclear2 StartulpReactor shutdown margin is less than Technical Specification minimum required(keff> 0.99) and less than or equal to 5% rated thermal power.3 Hot StandbyReactor shutdown margin greater than Technical Specification minimum required(keff < 0.99) with coolant temperature (Tavg) greater than or equal to 300°F.4 Hot ShutdownReactor shutdown margin greater than Technical Specification minimum required(keff < 0.99) with coolant temperature (Tavg) less than 300°F and greater than 200°F.5 Cold ShutdownReactor shutdown margin greater than Technical Specification minimum required(keff < 0.99) with coolant temperature (Tavg) less than or equal to 200°F.6 RefuelReactor vessel head is unbolted.D DefueledAll reactor fuel removed from reactor pressure vessel (full core off load during refueling orextended outage).The plant operating mode that exists at the time that the event occurs (prior to any protectivesystem or operator action is initiated in response to the condition) should be compared to the modeapplicability of the EALs. If a lower or higher plant operating mode is reached before theemergency classification is made, the declaration shall be based on the mode that existed at thetime the event occurred.2.9 Validation of Indications, Reports and ConditionsAll emergency classifications shall be based upon valid indications, reports or conditions. Anindication, report, or condition, is considered to be valid when it is verified by (1) an instrumentchannel check, or (2) indications on related or redundant indicators, or (3) by direct observation byplant personnel, such that doubt related to the indicator's operability, the condition's existence, orthe report's accuracy is removed. Implicit in this definition is the need for timely assessment.February 2016 17 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclear2.10 Planned vs. Unplanned EventsPlanned evolutions involve preplanning to address the limitations imposed by the condition, theperformance of required surveillance testing, and the implementation of specific controls prior toknowingly entering the condition in accordance with the specific requirements of the site'sTechnical Specifications. Activities which cause the site to operate beyond that allowed by thesite's Technical Specifications, planned or unplanned, may result in an EAL threshold being met orexceeded. Planned evolutions to test, manipulate, repair, perform maintenance or modifications tosystems and equipment that result in an EAL value being met or exceeded are not subject toclassification and activation requirements as long as the evolution proceeds as planned and iswithin the operational limitations imposed by the specific operating license. However, theseconditions may be subject to the reporting requirements of 10 CFR 50.72.2.11 Classifying Transient EventsFor some events, the condition may be corrected before a declaration has been made. The keyconsideration in this situation is to determine whether or not further plant damage occurred whilethe corrective actions were being taken. In some situations, this can be readily determined, in othersituations, further analyses may be necessary (e.g., coolant radiochemistry following an ATWSevent, plant structural examination following an earthquake, etc.). Classify the event as indicatedand terminate the emergency once assessment shows that there were no consequences from theevent and other termination criteria are met.Existing guidance for classifying transient events addresses the period of time of event recognitionand classification (15 minutes). However, in cases when EAL declaration criteria may be metmomentarily during the normal expected response of the plant, declaration requirements shouldnot be considered to be met when the conditions are a part of the designed plant response, orresult from appropriate Operator actions.There may be cases in which a plant condition that exceeded an EAL was not recognized at thetime of occurrence but is identified well after the condition has occurred (e.g., as a result of routinelog or record review), and the condition no longer exists. In these cases, an emergency should notbe declared. Reporting requirements of 10 CFR 50.72 are applicable and the guidance of NUREG-1022, Event Reporting Guidelines 10 CFR 50.72 and 50.73, should be applied.February 2016 18 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclear2.12 Multiple Simultaneous Events and Imminent EAL ThresholdsWhen multiple simultaneous events occur, the emergency classification level is based on thehighest EAL reached. For example, two Alerts remain in the Alert category. Or, an Alert and a SiteArea Emergency is a Site Area Emergency. Further guidance is provided in RIS 2007-02,Clarification of NRC Guidance for Emergency Notifications During Quickly Changing Events.Since CCNPP is a multi-unit station with shared safety-related system and functions, emergencyclassification level upgrading must also consider the effects of a loss of a common system on morethan one unit (e.g., potential for radioactive release from more than one core). For example, thecontrol panels for both units are in close proximity within the same room. Thus, Control Roomevacuation most likely would affect both units. There are a number of other systems and functionswhich may be shared. This must be considered in the emergency classification level declaration.Although the majority of the EALs provide very specific thresholds, the Emergency Director (ED)must remain alert to events or conditions that lead to the conclusion that exceeding the EALthreshold is imminent. If, in the judgment of the ED, an imminent situation is at hand, theclassification should be made as if the threshold has been exceeded. While this is particularlyprudent at the higher emergency classes (the early classification may permit more effectiveimplementation of protective measures), it is nonetheless applicable to all emergency classes.2.13 Emergency Classification Level DowngradingAnother important aspect of usable EAL guidance is the consideration of what to do when the riskposed by an emergency is clearly decreasing. A combination approach involving recovery fromGeneral Emergencies and some Site Area Emergencies and termination from Unusual Events,Alerts, and certain Site Area Emergencies causing no long term plant damage appears to be thebest choice. Downgrading to lower emergency classification levels adds notifications but may havemerit under certain circumstances.February 2016 19 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclear

3.0 REFERENCES

3.1 Developmental3.1.1 NEI 99-01 Rev. 5 Final, Methodology for Development of Emergency ActionLevels, February 2008, ADAMS Accession Number ML080450 1493.1.2 NRC Regulatory Issue Summary (RIS) 2003-18, Supplement 2, Use of NuclearEnergy Institute (NEI) 99-01, Methodology for Development of Emergency ActionLevels Revision 4, Dated January 2003 (December 12, 2005)3.1.3 RIS 2007-02 Clarification of NRC Guidance for Emergency Notifications DuringQuickly Changing Events3.2 Implementing3.2.13.2.23.2.33.2.4EAL-HOT MatrixEAL-COLD MatrixEAL Comparison MatrixEAL Matrix3.3 CommitmentsNoneFebruary 201620EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclear4.0 DEFINITIONS (ref. 3.1.1 except as noted)Affecting Safe ShutdownEvent in progress has adversely affected functions that are necessary to bring the plant to andmaintain it in the applicable hot or cold shutdown condition. Plant condition applicability isdetermined by Technical Specification LCOs in effect.Example 1: Event causes damage that results in entry into an LCO that requires the plant to beplaced in hot shutdown. Hot shutdown is achievable, but cold shutdown is not. This event is not"affecting safe shutdown."Example 2: Event causes damage that results in entry into an LCO that requires the plant to beplaced in cold shutdown. Hot shutdown is achievable, but cold shutdown is not. This event is"affecting safe shutdown."Airliner/Large AircraftAny size or type of aircraft with the potential for causing significant damage to the plant (refer to theSecurity Plan for a more detailed definition).BombRefers to an explosive device suspected of having sufficient force to damage plant systems orstructures.Civil DisturbanceA group of people violently protesting station operations or activities at the site.Confinement BoundaryThe barrier(s) between areas containing radioactive substances and the environment.Containment ClosureThe site specific procedurally defined actions taken to secure Containment and its associatedstructures, systems, and components as a functional barrier to fission product release underexisting plant conditions. As applied to CCNPP, Containment Closure is the action or condition thatensures Containment and its associated systems, structures or components (SSC), as listed inSTP O-55A, provide a functional barrier to fission product release.ExplosionA rapid, violent, unconfined combustion, or catastrophic failure of pressurized/energized equipmentthat imparts energy of sufficient force to potentially damage permanent structures, systems, orcomponents.ExtortionAn attempt to cause an action at the station by threat of force.FaultedIn a steam generator, the existence of secondary side leakage that results in an uncontrolled dropin steam generator pressure or the steam generator being completely depressurized.February 2016 21 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearFireCombustion characterized by heat and light. Sources of smoke such as slipping drive belts oroverheated electrical equipment do not constitute fires. Observation of flame is preferred but is notrequired if large quantities of smoke and heat are observed.HostageA person(s) held as leverage against the station to ensure that demands will be met by the station.Hostile ActionAn act toward CCNPP or its personnel that includes the use of violent force to destroy equipment,take hostages, and/or intimidate the licensee to achieve an end. This includes attack by air, land,or water using guns, explosives, projectiles, vehicles, or other devices used to deliver destructiveforce. Other acts that satisfy the overall intent may be included.Hostile Action should not be construed to include acts of civil disobedience Or felonious acts thatare not part of a concerted attack on CCNPP. Non-terrorism-based EALs should be used toaddress such activities, (e.g., violent acts between individuals in the owner controlled area).Hostile ForceOne or more individuals who are engaged in a determined assault, overtly or by stealth anddeception, equipped with suitable weapons capable of killing, maiming, or causing destruction.ImminentMitigation actions have been ineffective, additional actions are not expected to be successful, andtrended information indicates that the event or condition will occur. Where imminent timeframes arespecified, they shall apply.IntrusionThe act of entering without authorization. Discovery of a bomb in a specified area is indication ofintrusion into that area by a hostile force.Independent Spent Fuel Storage Installation (ISFSI)A complex that is designed and constructed for the interim storage of spent nuclear fuel and otherradioactive materials associated with spent fuel storage.Normal LevelsAs applied to radiological IC/EALs, the highest reading in the past twenty-four hours excluding thecurrent peak value.Normal Plant OperationsActivities at the plant site associated with routine testing, maintenance, or equipment operations, inaccordance with normal operating or administrative procedures. Entry into abnormal or emergencyoperating procedures, or deviation from normal security or radiological controls posture, is adeparture from Normal Plant Operations.ProjectileAn object directed toward a NPP that could cause concern for its continued operability, reliability,or personnel safety.February 2016 22 EP-AA-1011lAddendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearProtected AreaThe site specific area which normally encompasses all controlled areas within the securityProtected Area fence.RupturedIn a steam generator, existence of primary-to-secondary leakage of a magnitude sufficient torequire or cause a reactor trip and safety injection.SabotageDeliberate damage, mis-alignment, or mis-operation of plant equipment with the intent to renderthe equipment inoperable. Equipment found tampered with or damaged due to malicious mischiefmay not meet the definition of sabotage until this determination is made by security supervision.Safety-Related Structures, Systems or Component (as defined in 10CFR50.2)Those structures, systems and components that are relied upon to remain functional during andfollowing design basis events to assure:(1) The integrity of the reactor coolant pressure boundary;(2) The capability to shut down the reactor and maintain it in a safe shutdown condition;(3) The capability to prevent or mitigate the consequences of accidents which could result inpotential offsite exposures.Security ConditionAny security event as listed in the approved security contingency plan that constitutes athreaticompromise to site security, threat/risk to site personnel, or a potential degradation to thelevel of safety of the plant. A security condition does not involve a hostile action.Strike ActionWork stoppage within the Protected Area by a body of workers to enforce compliance withdemands made on CCNPP. The strike action must threaten to interrupt Normal Plant Operations.UnisolableA breach or leak that cannot be promptly isolated.UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is not theresult of an intended evolution or expected plant response to a transient.ValidAn indication, report, or condition, is considered to be valid when it is verified by (1) an instrumentchannel check, or (2) indications on related or redundant indicators, or (3) by direct observation byplant personnel, such that doubt related to the indicator's operability, the condition's existence, orthe report's accuracy is removed. Implicit in this definition is the need for timely assessment.February 2016 23 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearVisible DamageDamage to equipment or structure that is readily observable without measurements, testing, oranalysis. Damage is sufficient to cause concern regarding the continued operability or reliability ofaffected safety structure, system, or component. Example damage includes: deformation due toheat or impact, denting, penetration, rupture, cracking, paint blistering. Surface blemishes (e.g.,paint chipping, scratches) should not be included.Vital AreaAny areas, normally within the CCNPP Protected Area, that contains equipment, systems,components, or material, the failure, destruction, or release of which could directly or indirectlyendanger the public health and safety by exposure to radiation.February 201624EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclear5.0 CCNPP-TO-NEI 99-01 EAL CROSSREFERENCEThis cross-reference is provided to facilitate association and location of a CCNPP EAL within theNEI 99-01 IC/EAL identification scheme. Further information regarding the development of theCCNPP EALs based on the NEI guidance can be found in the EAL Comparison Matrix.CCNPP NEI 99-01EAL IC ExampleEAL ICEALRU1.1 AU1 1RU1.2 AU1 3RU2.1 AU2 1RU2.2 AU2 2RA1.1 AA1 1RA1.2 AA1 3RA2.1 AA2 2RA2.2 AA2 1RA3.1 AA3 1RS1.1 AS1 1RS1.2 AS1 2RS1.3 AS1 4RG1.1 AG1 1RG1.2 AG1 2RG1.3 AG1 4EUI.1 E-HU1 1CUI.1 CU3 1CU2.1 CU7 1CU3.1 CU1 1CU3.2 CU2 1February 201625EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCCNPP NEI 99-01EAL ICExampleEAL ICEALCU3.3 CU2 2CU4.1 CU4 1CU4.2 CU4 2CU5.1 CU6 1, 2CU6.1 CU8 2CA 1.1 CA3 1CA3.1 CA1 1, 2CA4.1 CA4 1, 2CS3.1 CS1 1CS3.2 0S1 2CS3.3 0S1 3CG3.1 CG1 1CG3.2 CG1 2FU1.1 FU1 1FA1.1 FA1 1FS1.1 FS1 1FG1.1 FGI 1HUI.1 HU1 1HU1.2 HU1 2HU1.3 HU1 '3HU1.4 HU1 4HU1.5 HU1 5HU2.1 HU2 1HU2.2 HU2 2HU3.1 HU3 1February 201626EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCCNPP NEI 99-01EAL ICExampleEAL ICEALHU3.2 HU3 2HU4.1 HU4 1, 2, 3HU6.1 HU5 .1HAl.1 HAl 1HA1.2 HA1 2HA1.3 HA1 3HA1.4 HA1 4HA1.5 HA1 6HA1.6 HA1 5HA2.1 HA2 1HA3.1 HA3 1HA4.1 HA4 1, 2HA5.1 HA5 1HA6.1 HA6 1HS4.i HS4 1HS5.1 HS2 1HS6.1 HS3 1HG4.1 HG1 1HG4.2 HG1 2HG6.1 HG2 ISUl.1 SU1 1SU3.1 SU8 1SU4.1 SU2 1SU5.1 SU3 1SU6.1 SU6 1, 2February 201627EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCCNPP NEI 99-01EAL ICExampleEAL ICEALSU7.1 SU4 2SU7.2 SU4 1SU8.1 SU5 1, 2SA1.1 SA5 1SA3.1 SA2 1SA5.1 SA4 1SS1.1 SS11SS2.1 SS3 1SS3.1 SS21SS5.1 SS6 1SG1.1 SG1 1SG3.1 SG2 1February 201628EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclear6.0 ATTACHMENTS6.1 Attachment 1, Emergency Action Level Technical Bases6.2 Attachment 2, Fission Product Barrier Loss / Potential Loss Matrix and BasisFebruary 201629EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearAttachment 1Category R -Abnormal Rad Levels I Rad EffluentsEAL Group: ANY (EALs in this category are applicable to anyplant condition, hot or cold.)Many EALs are based on actual or potential degradation of fission product barriers because of theelevated potential for offsite radioactivity release. Degradation of fission product barriers though isnot always apparent via non-radiological symptoms. Therefore, direct indication of elevatedradiological effluents or area radiation levels are appropriate symptoms for emergencyclassification.At lower levels, abnormal radioactivity releases may be indicative of a failure of Containmentsystems or precursors to more significant releases. At higher release rates, offsite radiologicalconditions may result which require offsite protective actions. Elevated area radiation levels inplant may also be indicative of the failure of Containment systems or preclude access to plant vitalequipment necessary to ensure plant safety.Events of this category pertain to the following subcategories:1. Offsite Rad ConditionsDirect indication of effluent radiation monitoring systems provides a rapid assessmentmechanism to determine releases in excess of classifiable limits. Projected offsite doses,actual offsite field measurements or measured release rates via sampling indicate doses ordose rates above classifiable limits.2. Onsite Rad Conditions & Spent Fuel EventsSustained general area radiation levels in excess of those indicating loss of control ofradioactive materials or those levels which may preclude access to vital plant areas alsowarrant emergency classification.3. CR/CAS RadSustained general area radiation levels which may preclude access to areas requiringcontinuous occupancy also warrant emergency classification.February 2016 30 EP-AA-1O11 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:Initiating Condition:R -Abnormal Rad Release / Rad Effluent1 -Offsite Rad ConditionsANY release of gaseous or liquid radioactivity to the environmentgreater than 2 times the ODCM for 60 minutes or longerEAL:RUI.1 Unusual EventANY gaseous or liquid monitor reading > Table R-1 column "UE" for _> 60 min. (Note 2)Note 2: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the release duration has exceeded, or will likely exceed, the applicable time. In the absence*of data to the contrary, assume that the release duration has exceeded the applicable time if an ongoingrelease is detected and the release start time is unknown.Table R-1 Effluent Monitor Classification ThresholdsMonitor GE SAE Alert J UEGaseousWRNGM 3.2E+09 IJCi/sec 3.2E+08 pCi/sec 3.2E+07 pCi/sec 3.2E+05 pCi/sec(RIC-541 5)Main Steam Effluent(RIC 5421/5422) 2.99E+04 iiCi/cc 2.99E+03 jiCi/cc 2.99E+i02 p~Ci/cc N/AMain Vent(RI-5415) N/A N/A N/A 2.OE+05 cpmWaste Processing(RI-5410) N/A N/A N/A 4.0E+05 cpmFuel Handling Area Vent(RI-5420) N/A N/A N/A 3.4E+05 cpmLiquid Waste Disch*(RE-2201) N/A N/A N/A 8.4E+05 cpm* with effluent discharge not isolatedMode Applicability:AllBasis:GenericThe Emergency Director should not wait until the applicable time has elapsed, but should declarethe event as soon as it is determined that the condition will likely exceed the applicable time.This EAL addresses a potential decrease in the level of safety of the plant as indicated by aradiological release that exceeds regulatory commitments for an extended period of time.February 201631EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearNuclear power plants incorporate features intended to control the release of radioactive effluents tothe environment. Further, there are administrative controls established to prevent unintentionalreleases, or control and monitor intentional releases. The occurrence of extended, uncontrolledradioactive releases to the environment is indicative of a degradation in these features and/orcontrols.The 2 x 00CM limit multiples are specified only to distinguish between non-emergency conditions.While these multiples obviously correspond to an off-site dose or dose rate, the emphasis inclassifying these events is the degradation in the level of safety of the plant, not the magnitude ofthe associated dose or dose rate.Releases should not be prorated or averaged. For example, a release exceeding 4x ODCM for 30minutes does not meet the threshold.This EAL includes any release for which a radioactivity discharge permit was not prepared, or arelease that exceeds the conditions (e.g., minimum dilution flow, maximum discharge flow, alarmsetpoints, etc.) on the applicable permit.This EAL addresses radioactivity releases, that for whatever reason, cause effluent radiationmonitor readings to exceed the threshold identified in the IC.This EAL is intended for sites that have established effluent monitoring on non-routine releasepathways for which a discharge permit would not normally be prepared.Plant-SpecificThe main plant vents consist of the exhaust flow from the auxiliary building ventilation systems andthe condenser offgas system. Batch releases from the Waste Gas Decay Tanks, Containmentvents and Containment purges are also directed into this stream. Per 00CM Attachment 7, theUnit 1 and Unit 2 vent flow rates are assumed to be 56.3 m3/sec and 42.7 m3/sec, respectively.Each plant vent is monitored by a beta sensitive plastic scintillator Wide Range Noble Gas Monitor(WRNGM 1-RIC-5415 and 2-RIC-5415) which is displayed in pCi/sec and a Geiger-Muller tubeMain Vent Monitor (1-RI-5415 and 2-RI-5415) which is displayed in CPM. The EAL values weredetermined assuming annual average meteorology, RCS noble gas concentrations and doseconversion factors used for emergency preparedness offsite dose assessment. The total gaseousrelease corresponding to 2 times 00CM limits is approximately 0.114 mrem in one hour ascalculated below.1. 2 x 00CM = 2 x 500 mrem/year = 1000 mrem/year2. Hours/year = 24 x 365 = 8760 hour0.101 days <br />2.433 hours <br />0.0145 weeks <br />0.00333 months <br />s/year3. (1000 mrem/year) / (8760 hour0.101 days <br />2.433 hours <br />0.0145 weeks <br />0.00333 months <br />s/year) = 0.114 mrem/hour (or 1.14E-3 mSv/hour)The values for the vent radiation monitor readings are based on 90% of the 2 maximumpermissible concentration (MPC) as discussed in 0DCM 3.11.2.1 at the site boundary. ThisFebruary 2016 32 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclearreduction will account for events that may result in releases through both unit vents. The 10%factor allowance for the other unit vent is conservative because it is two to three orders ofmagnitude larger than the normal releases through each vent. For the main vent monitors, whichread in CPM, the Unit 1 flow rate is assumed because it yields the lowest (most limiting)concentration.RIC-541 5 EAL ThresholdODCM limit corresponds to 1.8 E+5 tJCi/sec (site total)2 x 1.8 E+5 tpCi/sec = 3.6 E+5 pCi/secAssume event in one unit, allow 10% for release from other unitRIC-5415 EAL Threshold =0.9 x 3.6 E+5 pJCi/sec =3.24 E+5 pCi/secRead as 3.2 E+5 tpCi/secMinimum Concentration Corresponding to RI-5415 ReadingConcentration = Release rate (uCi/sec)Flow rate (cc/sec)Unit 10ODCM flow rates = 56.3 m3/secUnit 1 Concentration = 3.24 E+5 uJCi/sec56.3 m3/sec x 106 cc/rn3=5.7 E-3 Unit 20ODCM flow rates = 42.7 m3/secUnit 2 Concentration = 3.24 E+5 uCi/sec42.7 m3/sec x 10~6 cc/rn3=7.6 E-3 i.Ci/ccThe calculated concentration result is converted to CPM so it can be read on RI-5415.February 201633EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearUnit 1 Conc. Unit 2 Conc. Monitor Eff. Unit I Unit 2Isotope RCS Conc. % Total (IpCi/cc) (tpCi/cc) (CPM/10-6) CPM CPMKr-85 0.43 9.62 5.5 E-4 7.3 E-4 35 1.9 E+4 2.6 E+4Kr-85m 0.16 3.58 2.1 E-4 2.7 E-4 55 1.2 E+4 1.5 E+4Kr-87 0.15 3.36 1.9 E-4 2.6 E-4 218 4.1 E+4 5.6 E+4Kr-88 0.28 6.36 3.7 E-4 4.8 E-4 289 1.1 E+5 1.4 E+5Xe-133 2.6 58.17 3.3 E-3 4.4 E-3 1.87 6.2 E+3 8.3 E+3Xe-135 0.85 19.01 1.1 E-3 1.4 E-3 70 7.7 E+4 1.0 E+5Totals 4.47 100.00 5.7 E-3 71!6 E-3 2.7 E+5 3.5 E+5The lower of the Unit 1 and Unit 2 values is conservatively rounded to 2.0E+5 CPM;In a similar manner, values were determined for the Waste Processing Monitor (1-RI-5410 and 2-Rl-5410) assuming noble gas distribution for Waste Gas Decay Tank rupture, average annualmeteorology and a nominal waste processing ventilation flow of 23.4 m3/sec (49,500 CFM). At 2DAC at the site boundary, this corresponds to a reading of 4.0 E+5 CPM.In a similar manner to that shown for RI-5415, values were determined for the Fuel Handling AreaVent Monitor (0-RI-5420) assuming only monitor response to noble gas released from a FuelHandling Incident, average annual meteorology and a nominal fuel handling area ventilation flow of15.1 m3/sec (32,000 CEM). At 2 DAC at the site boundary, per Reference 2 this corresponds to areading of 3.4 E+5 CPM.Analysis was also performed for potential releases through Access Control Point and ECCS Pump(PP) Room. Per Reference 2, 2 DAC at the site boundary corresponds to monitor readings foreach of these locations that are greater than 1 E+6 CPM (i.e., off-scale high). The EGOS PP RoomMonitors (1/2-RI-5406) and the Access Control Monitor (0-RI-5425) are not considered herebecause they will be offscale high at the Unusual Event emergency classification level. Therefore,these monitors provide no useful information for this EAL and are excluded from consideration.Liquid effluent is monitored by the Liquid Waste Discharge Radiation Monitor (0-RE-2201). A highradiation alarm from this monitor results in a signal to close the Liquid Waste Discharge Valves. Ifthese valves do not shut, the operators stop the pump being used for the discharge and shut theLiquid Waste RMS Outlet valve.February 201634EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearThe Steam Generator Blowdown liquid effluent monitor upper range cannot detect releasesassociated with two times the ODCM limits and therefore would be assessed per EAL RU1 .2sample analysis.The designation "N/A" in Table R-1 indicates that the listed instrument range is insufficient toindicate the specified value and therefore no value is used.A radiation monitor reading is valid when a release path is established. If the release path to theenvironment has been isolated, the radiation monitor reading is not valid for classification.CCNPP Basis Reference(s):1. Radioactivity Release Emergency Action Levels, J.B. Mcllvaine, JSB Associates, Inc.,September 19902. Off-Site Dose Calculation Manual (ODCM) for the Calvert Cliffs Nuclear Power Plant3. AOP-6B Accidental Release of Radioactive Liquid Waste4. UFSAR Section 11.1.2.1 Liquid Waste Processing System5. NEI 99-01 AU1February 201635EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:S ubcateg ory:R -Abnormal Rad Release/IRad Effluent1 -Offsite Rad ConditionsInitiating Condition: ANY release of gaseous or liquid radioactivity to the environmentgreater than 2 times the 0DCM for 60 minutes or longerEAL:RUI.2 Unusual EventConfirmed sample analyses for gaseous or liquid releases indicate concentrations orrelease rates > 2 x ODCM limits for > 60 min. (Note 2)Note 2: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the release duration has exceeded, or will likely exceed, the applicable time. In the absenceof data to the contrary, assume that the release duration has exceeded the applicable time if an ongoingrelease is detected and the release start time is unknown.Mode Applicability:AllBasis:GenericThe Emergency Director should not wait until the applicable time has elapsed, but should declarethe event as soon as it is determined that the condition will likely exceed the applicable time.This EAL addresses a potential decrease in the level of safety of the plant as indicated by aradiological release that exceeds regulatory commitments for an extended period of time.Nuclear power plants incorporate features intended to control the release of radioactive effluents tothe environment. Further, there are administrative controls established to prevent unintentionalreleases, or control and monitor intentional releases. The occurrence of extended, uncontrolledradioactive releases to the environment is indicative of a degradation in these features and/orcontrols.The 2 x 00CM limit multiples are specified only to distinguish between non-emergency conditions.While these multiples obviously correspond to an off-site dose or dose rate, the emphasis inclassifying these events is the degradation in the level of safety of the plant, not the magnitude ofthe associated dose or dose rate.Releases should not be prorated or averaged. For example, a release exceeding 4x ODCM for 30minutes does not meet the threshold.This EAL includes any release for which a radioactivity discharge permit was not prepared, or arelease that exceeds the conditions (e.g., minimum dilution flow, maximum discharge flow, alarmsetpoints, etc.) on the applicable permit.February 201636EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearThis EAL addresses uncontrolled releases that are detected by sample analyses, particularly onunmonitored pathways, e.g., spills of radioactive liquids into storm drains, heat exchanger leakagein river water systems, etc.Plant-SpecificReleases in excess of two times the site Offsite Dose Calculation Manual (ODCM) (ref. 1)instantaneous limits that continue for 60 minutes or longer represent an uncontrolled situation andhence, a potential degradation in the level of safety. The final integrated dose (which is very low inthe Unusual Event emergency class) is not the primary concern here; it is the degradation in plantcontrol implied by the fact that the release was not isolated within 60 minutes. Therefore, it is notintended that the release be averaged over 60 minutes. For example, a release of 4 times theODCM limit for 30 minutes does not exceed this initiating condition. Further, the ED should not waituntil 60 minutes has elapsed, but should declare the event as soon as it is determined that therelease duration has or will likely exceed 60 minutes.Sample analyses are "confirmed" when the analytical results have been confirmed by Chemistry.CCNPP Basis Reference(s):1. Off-Site Dose Calcu'lation Manual (ODCM) for the Calvert Cliffs Nuclear Power Plant2. NEI 99-01 AU1February 201637EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:R -Abnormal Rad Release / Rad EffluentSubcategory: 1 -Offsite Rad ConditionsInitiating Condition: ANY release of gaseous or liquid radioactivity to the environmentgreater than 200 times the ODCM for 15 minutes or longerEAL:RA1.1 AlertANY gaseous monitor reading > Table R-1 column "Alert" for -> 15 mai. (Note 2)Note 2: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the release duration has exceeded, or will likely exceed, the applicable time. In the absenceof data to the contrary, assume that the release duration has exceeded the applicable time if an ongoingrelease is detected and the release start time is unknown.[ Table R-1 Effluent Monitor Classification Thresholds[Monitor GE SAE Alert UEGaseousWRNGM 3.2E+09 pCi/sec 3.2E+08 pCi/sec 3.2E+07 IpCi/sec 3.2E+05 pCi/sec(RIC-541 5)Main Steam Effluent 2.99E+04 iiCi/cc 2.99E+03 p.Ci/cc 2.99E+02 p.Ci/cc N/A(RIC-5421/5422)Main Vent N/A N/A N/A 2.0E+05 cpm(RI-541 5)Waste Processing N/A N/A N/A 4.0E+i05 cpm(RI-541 0)Fuel Handling Area Vent N/A N/A N/A 3.4E+05 cpm(RI-5420)Liquid Waste Disch* N/A N/A N/A 8.4E+05 cpm(RE-2201)* with effluent discharge not isolatedMode Applicability: AllBasis:GenericThe Emergency Director should not wait until the applicable time has elapsed, but should declarethe event as soon as it is determined that the condition will likely exceed the applicable time.This EAL addresses an actual or substantial potential decrease in the level of safety of the plant asindicated by a radiological release that exceeds regulatory commitments for an extended period oftime.February 201638EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearNuclear power plants incorporate features intended to control the release of radioactive effluents tothe environment. Further, there are administrative controls established to prevent unintentionalreleases, or control and monitor intentional releases. The occurrence of extended, uncontrolledradioactive releases to the environment is indicative of a degradation in these features and/orcontrols.The 200 x 0DCM limit multiples are specified only to distinguish between non-emergencyconditions. While these multiples obviously correspond to an off-site dose or dose rate, theemphasis in classifying these events is the degradation in the level of safety of the Releasesshould not be prorated or averaged. For example, a release exceeding 600 x ODCM for 5 minutesdoes not meet the threshold.This EAL includes any release for which a radioactivity discharge permit was not prepared, or arelease that exceeds the conditions (e.g., minimum dilution flow, maximum discharge flow, alarmsetpoints, etc.) on the applicable permit.This EAL is intended for sites that have established effluent monitoring on non-routine releasepathways for which a discharge permit would not normally be prepared.Plant-SpecificA description of the applicable monitors and the methods used to calculate EAL values is shown inthe Bases for RU1 .1. Values for this EAL are based on the values shown in RU1 .1 multiplied by100.The ECCS PP Room Monitors (1/2-RI-5406) and the Access Control Monitor (0-RI-5425) are notconsidered here because they will be offscale high at the Unusual Event emergency classificationlevel. At the Alert level, the readings on the main vent monitors (1/2-RI-541 5), the WasteProcessing Vent Monitors (1/2-RI-541 0), and the Fuel Handling Area Vent Monitor (0-RI-5420) arewell above the top of the instrument indicated range (1 .0E+6 CPM). Therefore, these monitorsprovide no useful information for this EAL and are excluded from consideration.The purpose of the Main Steam Effluent Radiation Monitor System is to monitor possible noble gasreleases to the atmosphere from the main steam line through the atmospheric steam dump valves,the main steam safety relief valves, and the auxiliary feedwater steam turbine exhaust. The systemincludes two radiation monitors (1/2-RI-5421 and 1/2-RI-5422) per unit -one radiation monitor foreach steam generator. The noble gas release rate of 3.2E+7 pCi/second (which corresponds to awhole body dose of 10 mrem in one hour at the site boundary) may also occur through release viamain steam safety valve or atmospheric dump valve.February 2016 39 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCiav~rt AnnexlExnlnn Niil~r~IV Vl vlmm IV m ........ Vl i i EP-CALC-00001, Determination of Emergency Action Level Criteria for Calvert Cliffs NuclearPower Plant Main Steam Line Radiation Monitors, outlines, in detail, the calculation andmethodology demonstrated below.RAI .1 Threshold for RIC-5421, RIC-5422RGI.1 Threshold Value = 2.99 E+4 pCi/cc (see section RGI.1)GE Site Boundary Dose Threshold =1000 mremAlert Site Boundary Dose Threshold = 10 mremMain Steam Monitor Reading (pCi/cc) = Alert Site Boundary Dose Threshold X RGI.1 Threshold ValueGB Site Boundary Dose Threshold_10 mrem X29 lic-1000 mnrem X29 tic=2.99 E+2 pCi/ccBased on the March 14, 1993 SG tube rupture event at Palo Verde Unit 2, the main steam effluentmonitors (RI-5421, RI-5422) may read N16 immediately following SG tube rupture and prior toreactor trip. However, given the short half-life of N1 6, this should clear within the first minutefollowing reactor trip.The designation "N/A" in Table R-1 indicates that the listed instrument range is insufficient toindicate the specified value and therefore no value is used.A radiation monitor reading is valid when a release path is established. If the release path to theenvironment has been isolated, the radiation monitor reading is not valid for classification.CCNPP Basis Reference(s):1. Radioactivity Release Emergency Action Levels, J.B. Mcllvaine, JSB Associates, Inc.,September 19902. Off-Site Dose Calculation Manual (ODCM) for the Calvert Cliffs Nuclear Power Plant3. NEI 99-01 AA14. EP-CALC-00001, Determination of Emergency Action Level Criteria for Calvert Cliffs NuclearPower Plant Main Steam Line Radiation MonitorsFebruary 201640EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:S ubcategory:R -Abnormal Rad Release / Rad Effluent1 -Offsite Rad ConditionsInitiating Condition: ANY release of gaseous or liquid radioactivity to the environmentgreater than 200 times the ODCM for 15 minutes or longerEAL:RA1 .2 AlertConfirmed sample analyses for gaseous or liquid releases indicate concentrations orrelease rates > 200 x ODCM limits for > 15 min. (Note 2)Note 2: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the release duration has exceeded, or will likely exceed, the applicable time. In the absenceof data to the contrary, assume that the release duration has exceeded the applicable time if an ongoingrelease is detected and the release start time is unknown.Mode Applicability:AllBasis:GenericThe Emergency Director should not wait until the applicable time has elapsed, but should declarethe event as soon as it is determined that the condition will likely exceed the applicable time.This EAL addresses an actual or substantial potential decrease in the level of safety of the plant asindicated by a radiological release that exceeds regulatory commitments for an extended period oftime.Nuclear power plants incorporate features intended to control the release of radioactive effluents tothe environment. Further, there are administrative controls established to prevent unintentionalreleases, or control and monitor intentional releases. The occurrence of extended, uncontrolledradioactive releases to the environment is indicative of a degradation in these features and/orcontrols.The 200 x ODCM limit are specified only to distinguish between non-emergency conditions. Whilethese multiples obviously correspond to an off-site dose or dose rate, the emphasis in classifyingthese events is the degradation in the level of safety of the plant, not the magnitude of theassociated dose or dose rate.Releases should not be prorated or averaged. For example, a release exceeding 600 x ODCM for5 minutes does not meet the threshold.This EAL includes any release for which a radioactivity discharge permit was not prepared, or arelease that exceeds the conditions (e.g., minimum dilution flow, maximum discharge flow, alarmsetpoints, etc.) on the applicable permit.February 201641EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearThis EAL addresses uncontrolled releases that are detected by sample analyses, particularly onunmonitored pathways, e.g., spills of radioactive liquids into storm drains, heat exchanger leakage.Plant-SpecificConfirmed sample analyses in excess of two hundred times the site Offsite Dose CalculationManual (ODCM) limits that continue for 15 minutes or longer represent an uncontrolled situationand hence, a potential degradation in the level of safety. This event escalates from the UnusualEvent by raising the magnitude of the release by a factor of 100 over the Unusual Event level (i.e.,200 times ODCM). Prorating the 500 mRem/yr basis of the 10 CFR 20 non-occupational MPClimits for both time (8766 hr/yr) and the 200 multiplier, the associated Exclusion Area Boundarydose rate would be approximately 10 mRem/hr. If sample analysis indicates the threshold is metand nothing is done within 15 minutes to effect a release reduction, the ED can conclude that theEAL threshold is met without second sample results.Sample analyses are "confirmed" when the analytical results have been confirmed by Chemistry.CCNPP Basis Reference(s):1. Off-Site Dose Calculation Manual (ODCM) for Calvert Cliffs Nuclear Power Plant2. NEI 99-01 AAIFebruary 201642EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:Initiating Condition:R -Abnormal Rad Release/IRad Effluent1 -Offsite Rad ConditionsOffsite dose resulting from an actual or imminent release ofgaseous radioactivity exceeds 100 mRem TEDE or 500 mRemthyroid CDE for the actual or projected duration of the releaseusing actual meteorologyEAL:RSI .1 Site Area EmergencyANY radiation monitor reading > Table R-1 column "SAE" for _> 15 min. (Note 1)* Do not delay declaration awaiting dose assessment results* If dose assessment results are available, declaration should be based on doseassessment instead of radiation monitor values (see EAL RS1 .2)Note 1: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition will likely exceed the applicable timeTable R-1 Effluent Monitor Classification ThresholdsMonitor GE S AE ,Alert UEGaseousWRNGM 3.2E+09 pCi/sec 3.2E+08 pCi/sec 3.2E+07 pCi/sec 3.2E+05 pCi/sec(RIC-541 5)Main Steam Effluent 2.99E+'04 2.99 E+03 jiCi/cc 2.99 E+O2 jiCi/cc N/A(RlC-5421 /5422)Main Vent N/A N/A N/A 2.0E+05 cpm(RI-541 5)Waste Processing N/A N/A N/A 4.0E+05 cpm(RI-541 0)Fuel Handling Area Vent N/A N/A N/A 3.4E+05 cpm(RI-5420)Liquid Waste Disch* N/A N/A "N/A 8.4E+05 cpm(RE-2201)* with effluent discharge not isolatedMode Applicability:AllBasis:GenericThis EAL addresses radioactivity releases that result in doses at or beyond the site boundary thatexceed 10% of the EPA Protective Action Guides (PAGs). Releases of this magnitude areassociated with the failure of plant systems needed for the protection of the public.February 201643EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearThe site specific monitor list in Table R-1 includes effluent monitors on all potential releasepathways.Since dose assessment is based on actual meteorology, whereas the monitor reading EAL is not,the results from these assessments may indicate that the classification is not warranted, or mayindicate that a higher classification is warranted. For this reason, emergency implementingprocedures should call for the timely performance of dose assessments using actual meteorologyand release information. If the results of these dose assessments are available when theclassification is made (e.g., initiated at a lower classification level), the dose assessment resultsoverride the monitor reading EAL.Plant-SpecificThe Emergency Director (ED) should not wait until 15 minutes has elapsed, but should declare theevent as soon as it is determined that the release duration has or will likely exceed 15 minutes.A description of the applicable monitors and the methods used to calculate EAL values for theWRNGM is shown in RU1.1. Values for this EAL are based on the values shown in RU1.1 scaledup from 0.114 mrem in an hour (iLe., hourly rate resulting in 2 X 500 mrem in one year) to 100mrem (TEDE) (1 mSV) in an hour.The meteorology and source term (noble gases) used in determining the monitor readings in EALRSI.1 are the same as those used for determining the monitor readings in EALs RU1.1 andRA1 .1. Consistent use of these variables for all three EALs creates a protocol that maintainsconsistent intervals between the monitor readings for the four emergency classifications. Themonitor readings developed with this protocol are intended to be used only in situations in whichnormal dose assessment cannot be accomplished. Normal dose assessment methods incorporatethe actual accident meteorological variables and are the preferred methods for determining whenthis EAL is met.In keeping with this protocol, the monitor response release coefficient for a steam generator tuberupture contaminated with RCS activity is used rather than the release coefficient for a steamgenerator tube rupture contaminated with gap activity. This choice of source terms may appear tobe non-conservative. It is important to consider, however, that the EALs in other categoriescompensate for the apparent lack of conservatism. A loss or challenge to plant safety systems is aprecursor EAL for a radiological release of this magnitude. Furthermore, normal dose assessmentis the primary method for determining the offsite consequences and takes into account accidentmeteorology and source term.February 2016 44 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearRS1.1 Threshold for RIC-5415Scale up from RUI .1 uncorrected release rate of 3.6 E+5 pCi/secRSI.1 Value =100 mRem/hr x 3.6 E+5 uCi/sec0.114 mRem/hr (or .00114 mSv/hr)=3.2 E+8 pCi/secThis value corresponds to a concentration of about 5 pCi/cc and falls well within the range of theWRNGM.The purpose of the Main Steam Effluent Radiation Monitor System is to monitor possible noble gasreleases to the atmosphere from the main steam line through the atmospheric steam dump valves,the main steam safety relief valves and the auxiliary feedwater steam turbine exhaust. The systemincludes two radiation monitors (1/2-RI-5421 and 1/2-RI-5422) per unit -one radiation monitor foreach steam generator.The noble gas release rate of 3.2E+8 IpCi/sec (which corresponds a whole body dose of 100 mremin one hour at the site boundary) may also occur through release via the main steam safety valveor atmospheric dump valve.EP-CALC-00001, Determination of Emergency Action Level Criteria for Calvert Cliffs NuclearPower Plant Main Steam Line Radiation Monitors, outlines, in detail, the calculation andmethodology demonstrated below.RAI.1 Threshold for RIC-5421, RIC-5422RG1.1 Threshold Value = 2.99 E+4 IpCi/cc (see section RGI.1)GE Site Boundary Dose Threshold = 1000 mremSAE Site Boundary Dose Threshold = 100 mremMain Steam Monitor Reading (pCi/cc) =SAE. Site Boundary Dose Threshold X RGL.1 Threshold ValueGE Site Boundary Dose Threshold_100 mrem X29 tic-loeo mrem X29 iic= 2.99 E+3 pCi/ccFebruary 201645EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBased on the March 14, 1993 SG tube rupture event at Palo Verde Unit 2, the main steam effluentmonitors (RI-5421, RI-5422) may read N16 immediately following SG tube rupture and prior toreactor trip. However, given the short half-life of N16, this should clear within the first minutefollowing reactor trip.Dose assessment performed in accordance with ERPIP 822, Initial Dose Assessment ManualCalculation Methods, or EP-AA-1 10-202, CCNPP Dose Assessment, is based on actualmeteorology but the monitor reading thresholds in this EAL are based on assumed meteorology.As a result, dose assessment may indicate that emergency classification is not warranted, eventhough the monitor reading threshold has been exceeded. For this reason, emergencyimplementing procedures call for the timely performance of dose assessments using actualmeteorology and release information. If the results of dose assessments are available whenemergency classification is being evaluated (e.g., initiated at a lower classification level), the doseassessment results override the monitor readings listed in Table R-1.The designation "N/A" in Table R-1 indicates that the listed instrument range is insufficient toindicate the specified value and therefore no value is used.A radiation monitor reading is valid when a release path is established. If the release path to theenvironment has been isolated, the radiation monitor reading is not valid for classification.CCNPP Basis Reference(s):1. Radioactivity Release Emergency Action Levels, J.B. Mcllvaine, JSB Associates, Inc.,September 19902. Off-Site Dose Calculation Manual (ODCM) for the Calvert Cliffs Nuclear Power Plant3. ERPIP 822, Initial Dose Assessment Manual Calculation Methods4. EP-AA-110-202, CCNPP Dose Assessment5. NEI 99-01 ASi6. EP-CALC-QOO01, Determination of Emergency Action Level Criteria for Calvert Cliffs NuclearPower Plant Main Steam Line Radiation MonitorsFebruary 2016 46 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:R -Abnormal Rad Release / Rad Effluent1 -Offsite Rad ConditionsInitiating Condition: Offsite dose resulting from an actual or imminent release of gaseousradioactivity exceeds 100 mRem TEDE or 500 mRem thyroid CDE forthe actual or projected duration of the release using actualmeteorologyEAL:RSI .2 Site Area EmergencyDose assessment using actual meteorology indicates doses > 100 mRem TEDE or500 mRem thyroid ODE at or beyond the site boundaryMode Applicability:AllBasis:GenericThis EAL addresses radioactivity releases that result in doses at or beyond the site boundary thatexceed 10% of the EPA Protective Action Guides (PAGs). Releases of this magnitude areassociated with the failure of plant systems needed for the protection of the public.Since dose assessment is based on actual meteorology, whereas the monitor reading EAL is not,the results from these assessments may indicate that the classification is not warranted, or mayindicate that a higher classification is warranted. For this reason, emergency implementingprocedures should call for the timely performance of dose assessments using actual meteorologyand release information. If the results of these dose assessments are available when theclassification is made (e.g., initiated at a lower classification level), the dose assessment resultsoverride the monitor reading EAL.Plant-SpecificThe 100 mRem TEDE dose is set at 10% of the EPA PAG, while the 500 mRem thyroid ODE wasestablished in consideration of the 1:5 ratio of the EPA PAG for TEDE and thyroid ODE.The site boundary is depicted on CCNPP 0DCM Attachment 18 "Environmental Monitoring Sites"(ref. 1). The site boundary is approximately a one-mile radius around the Protected Area. Per doseassessment methodology, the SB designated the Exclusion Area Boundary (EAB) is defined as1150 meters (0.71- miles), which is the minimum distance to the SB. ERPIP-822 assumes a SB orEAB of 0.7 miles.February 201647EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclea~rCCNPP Basis Reference(s):1. 0ff-Site Dose Calculation Manual (00CM) for the Calvert Cliffs Nuclear Power Plant2. ERPIP 822, Initial Dose Assessment Manual Calculation Methods3. NEI 99-01 AS1February 201648EP-AA-1 011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert AnnexFxI~xnn N~irlIn:ar......... I mIV I ....... I m m Category:Su bcategory:Initiating Condition:R -Abnormal Rad Release/IRad Effluent1 -Offsite Rad ConditionsOffsite dose resulting from an actual or imminent release ofgaseous radioactivity exceeds 100 mRem TEDE or 500 mRemthyroid CDE for the actual or projected duration of the releaseusing actual meteorologyEAL:RS1 .3 Site Area EmergencyField survey results indicate closed window dose rates > 100 mRem/hr expected tocontinue for _> 60 min. at or beyond the site boundaryORAnalyses of field survey samples indicate thyroid CDE > 500 mRem for 1 hr of inhalation ator beyond the site boundary (Note 1)determined that the condition will likely exceed the applicable timeMode Applicability:AllBasis:GenericThis EAL addresses radioactivity releases that result in doses at or beyond the site boundary thatexceed 10% of the EPA Protective Action Guides (PAGs). Releases of this magnitude areassociated with the failure of plant systems needed for the protection of the public.Since dose assessment is based on actual meteorology, whereas the monitor reading EAL is not,the results from these assessments may indicate that the classification is not warranted, or mayindicate that a higher classification is warranted. For this reason, emergency implementingprocedures should call for the timely performance of dose assessments using actual meteorologyand release information. If the results of these dose assessments are available when theclassification is made (e.g., initiated at a lower classification level), the dose assessment resultsoverride the monitor reading EAL.February 201649EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryAnnAxF:vAlnn N~mlcil~rVI b VII IV I II II I I Plant-SpecificThe site boundary is depicted on CCNPP ODCM Attachment 18 "Environmental Monitoring Sites"(ref. 1). The site boundary is approximately a one-mile radius around the Protected Area. Per doseassessment methodology, the SB designated the Exclusion Area Boundary (EAB) is defined as1150 meters (0.71 miles), which is the minimum distance to the SB. ERPIP-822 assumes a SB orEAB of 0.7 miles.CCNPP Basis Reference(s):1. Off-Site Dose Calculation Manual (0DCM) for the Calvert Cliffs Nuclear Power Plant2. NEI 99-01 AS1February 201650EP-AA-1 011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:Initiating Condition:R -Abnormal Rad Release/IRad Effluent1 -Offsite Rad ConditionsOffsite dose resulting from an actual or imminent release ofgaseous radioactivity greater than 1,000 mRem TEDE or 5,000mRem thyroid CDE for the actual or projected duration of therelease using actual meteorologyEAL:RGI.1 General EmergencyANY radiation monitor reading > Table R-1 column "GE" for > 15 min. (Note 1)* Do not delay declaration awaiting dose assessment results* If dose assessment results are available, declaration should be based on doseassessment instead of radiation monitor values (see EAL RG1 .2)Note 1: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition will likely exceed the applicable timeTable R-1 Effluent Monitor Classification ThresholdsMonitor [ GE ] SAE Alert UEGaseousWRNGM 3.2E+09 pCi/sec 3.2E+08 pCi/sec 3.2E+07 pCi/sec 3.2E+05 pCi/sec(RIC-541 5)Main Steam Effluent 2.99E+04 ~tCi/cc 2.99E+'03 2.99E+02 p.Ci/cc N/A(RIC-5421/5422)Main Vent N/A N/A N/A 2.0E+05 cpm(RI-541 5)Waste Processing N/A N/A N/A 4.0E+05 cpm(RI-541 0)Fuel Handling Area Vent N/A N/A N/A 3.4E+05 cpm(RI-5420)Liquid Waste Disch* N/A N/A N/A 8.4E+05 cpm(RE-2201)* with effluent discharge not isolatedMode Applicability:AllBasis:GenericThis EAL addresses radioactivity releases that result in doses at or beyond the site boundary thatexceed the EPA Protective Action Guides (PAGs). Public protective actions will be necessary.Releases of this magnitude are associated with the failure of plant systems needed for theprotection of the public and likely involve fuel damage.February 201651EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearThe monitor list in Table R-1 includes effluent monitors on all potential release pathways.Since dose assessment is based on actual meteorology, whereas the monitor reading EAL is not,the results from these assessments may indicate that the classification is not warranted, or mayindicate that a higher classification is warranted. For this reason, emergency implementingprocedures should call for the timely performance of dose assessments using actual meteorologyand release information. If the results of these dose assessments are available when theclassification is made (e.g., initiated at a lower classification level), the dose assessment resultsoverride the monitor reading EAL.Plant-SpecificA description of the applicable monitors and the methods used to calculate EAL values for theWRNGM is shown in EAL RU1.1. Values for this EAL are based on the values shown in RU1.1scaled up from 0.114 mrem in an hour (iLe., hourly rate resulting in 2 X 500 mrem in one year) to1000 mrem (TEDE) (10 mSV) in an hour.The meteorology and source term (noble gases) used in determining the monitor reading EAL inRG1 .1 are the same as those used for determining the monitor reading EALs in EALs RU1 .1,RA1.1 and RS1.1. Consistent use of these variables for all four EALs creates a protocol thatmaintains consistent intervals between the monitor readings for the four emergency classifications.The monitor readings developed with this protocol are intended to be used only in situations inwhich normal dose assessment cannot be accomplished. Normal dose assessment methodsincorporate the actual accident meteorological variables and are the preferred methods fordetermining when this EAL is met.In keeping with this protocol, the monitor response release coefficient for a steam generator tuberupture contaminated with RCS activity is used rather than the release coefficient for a steamgenerator tube rupture contaminated with gap activity. This choice of source terms may appear tobe non-conservative. The EALs in other categories compensate for this apparent lack ofconservatism. A loss or challenge to plant safety systems is a precursor EAL for a radiologicalrelease of this magnitude. Normal dose assessment is the primary method for determining theoffsite consequences and takes into account the accident meteorology and source term.February 2016 52 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryAnnc'vFvI:,lnn rL vimiiv i t iiiv kAVIVI I i 1 twI V I ira((14 IRG1.1 Threshold for RIC-5415Scale up from RUI .1 uncorrected release rate of 3.6 E+5 pCi/secRGI.1 Value = 1000 mRem/hr x 3.6 E+5 uJCi/sec0.114 mRem/hr (or .00114 mSvlhr)= 3.2 E+9 pJCi/secThis value corresponds to a concentration of about 50 IpCi/cc and falls well within the range of theWRNGM.The purpose of the Main Steam Effluent Radiation Monitor System is to monitor possible noble gasreleases to the atmosphere from the main steam line through the atmospheric steam dump valves,the main steam safety relief valves, and the auxiliary feedwater steam turbine exhaust. The systemincludes two radiation monitors (1/2-RI-5421 and 1/2-RI-5422) per unit -one radiation monitor foreach steam generator.The noble gas release rate of 3.2 E+9 IpCi/sec (which corresponds a whole body dose of 1000mrem in one hour at the site boundary) may also occur through release via main steam safetyvalve or atmospheric dump valve.February 201653EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryAnnoyNnnr~tl.rEP-CALC-OOO01, Determination of Emergency Action Level Criteria for Calvert Cliffs NuclearPower Plant Main Steam Line Radiation Monitors, outlines, in detail, the calculation andmethodolodgy demonstrated below:RG1.1 Threshold for RIC-542i, RIC-5422Release Rate = 3.2 E+9 pCi/sec (see above)Safety Valve Flow Rate = 2.44 E+6 cc/secRelease Concentration (pJCi/cc) =Release RateSafety Valve Flow Rate= 3.2 E+9 uJCi/cc2.44 E+6 cc/sec=1.31 E+3 pJCi/ccDetector response factors were applied to obtain a Main Steam Monitor reading of:2.99 E+4 pCilccBased on the March 14, 1993 SG tube rupture event at Palo Verde Unit 2, the main steam effluentmonitors (RIC-5421, RIC-5422) may read N16 immediately following SG tube rupture and prior toreactor trip. However, given the short half-life of N16, this should clear within the first minutefollowing reactor trip.Dose assessment performed in accordance with ERPIP 822, Initial Dose Assessment ManualCalculation Methods, or EP-AA-1 10-202, CCNPP Dose Assessment, is based on actualmeteorology but the monitor reading thresholds in this EAL are based on assumed meteorology.As a result, dose assessment may indicate that emergency classification is not warranted, eventhough the monitor reading threshold has been exceeded. For this reason, emergencyimplementing procedures call for the timely performance of dose assessments using actualmeteorology and release information. If the results of dose assessments are available whenemergency classification is being evaluated (e.g., initiated at a lower classification level), the doseassessment results override the monitor readings listed in Table R-I.February 201654EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearThe designation "N/A" in Table R-1 indicates that the listed instrument range is insufficient toindicate the specified value and therefore no value is used.A radiation monitor reading is valid when a release path is established. If the release path to theenvironment has been isolated, the radiation monitor reading is not valid for classification.CCNPP Basis Reference(s):1. Radioactivity Release Emergency Action Levels, J.B. Mcllvaine, JSB Associates, Inc.,September 19902. Off-Site Dose Calculation Manual (00CM) for the Calvert Cliffs Nuclear Power Plant3. ERPIP 822, Initial Dose Assessment Manual Calculation Methods4. EP-AA-1 10-202, CCNPP Dose Assessment5. NEI 99-01 AG16. EP-CALC-00001, Determination of Emergency Action Level Criteria for Calvert Cliffs NuclearPower Plant Main Steam Line Radiation MonitorsFebruary 201655EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:R -Abnormal Rad Release / Rad Effluent1 -Offsite Rad ConditionsInitiating Condition: Offsite dose resulting from an actual or imminent release ofgaseous radioactivity greater than 1,000 mRem TEDE or 5,000mRem thyroid CDE for the actual or projected duration of therelease using actual meteorologyEAL:RGI.2 General EmergencyDose assessment using actual meteorology indicates doses > 1,000 mRem TEDE or5,000 mRem thyroid CDE at or beyond the site boundaryMode Applicability:AllBasis:GenericThis EAL addresses radioactivity releases that result in doses at or beyond the site boundary thatexceed the EPA Protective Action Guides (PAGs). Public protective actions will be necessary.Releases of this magnitude are associated with the failure of plant systems needed for theprotection of the public and likely involve fuel damage.Since dose assessment is based on actual meteorology, whereas the monitor reading EAL is not,the results from these assessments may indicate that the classification is not warranted, or mayindicate that a higher classification is warranted. For this reason, emergency implementingprocedures should call for the timely performance of dose assessments using actual meteorologyand release information. If the results of these dose assessments are available when theclassification is made (e.g., initiated at a lower classification level), the dose assessment resultsoverride the monitor reading EAL.Plant-SpecificThe 1,000 mRem TEDE dose is set at 100% of the EPA PAG, while the 5,000 mRem thyroid ODEwas established in consideration of the 1:5 ratio of the EPA PAG for TEDE and thyroid ODE.The site boundary is depicted on CCNPP ODCM Attachment 18 "Environmental Monitoring Sites"(ref. 1). The site boundary is approximately a one-mile radius around the Protected Area. Per doseassessment methodology, the SB designated the Exclusion Area Boundary (EAB) is defined as1150 meters (0.71 miles), which is the minimum distance to the SB. ERPIP-822 assumes a SB orEAB of 0.7 miles.February 201656EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryC.nlvwrt AnncoyFvclnn rW MR Vml B mY B II me i i CCNPP Basis Reference(s):1. Off-Site Dose Calculation Manual (ODCM) for the Calvert Cliffs Nuclear Power Plant2. ERPIP 822, Initial Dose Assessment Manual Calculation Methods3. NEI 99-01 AG1February 201657EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuc~learCategory:R -Abnormal Rad Release / Rad EffluentSubcategory: 1 -Offsite Rad ConditionsInitiating Condition: Offsite dose resulting from an actual or imminent release ofgaseous radioactivity greater than 1,000 mRem TEDE or 5,000mRem thyroid CDE for the actual or projected duration of therelease using actual meteorologyEAL:RGI.3 General EmergencyField survey results indicate closed window dose rates > 1,000 mRem/hr expected tocontinue for _> 60 mai. at or beyond the site boundaryORAnalyses of field survey samples indicate thyroid CDE > 5,000 mRem for 1 hr of inhalationat or beyond the site boundary (Note 1)determined that the condition will likely exceed the applicable timeMode Applicability:AllBasis:GenericThis EAL addresses radioactivity releases that result in doses at or beyond the site boundary thatexceed the EPA Protective Action Guides (PAGs). Public protective actions will be necessary.Releases of this magnitude are associated with the failure of plant systems needed for theprotection of the public and likely involve fuel damage.Since dose assessment is based on actual meteorology, whereas the monitor reading EAL is not,the results from these assessments may indicate that the classification is not warranted, or mayindicate that a higher classification is warranted. For this reason, emergency implementingprocedures should call for the timely performance of dose assessments using actual meteorologyand release information. If the results of these dose assessments are available when theclassification is made (e.g., initiated at a lower classification level), the dose assessment resultsoverride the monitor reading EAL.February 201658EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearPlant-SpecificThe site boundary is depicted on CCNPP ODCM Attachment 18 "Environmental Monitoring Sites"(ref. 1). The site boundary is approximately a one-mile radius around the Protected Area. Per doseassessment methodology, the SB designated the Exclusion Area Boundary (EAB) is defined as1150 meters (0.71 miles), which is the minimum distance to the SB. ERPIP-822 assumes a SB orEAB of 0.7 miles.CCNPP Basis Reference(s):1. Off-Site Dose Calculation Manual (ODOM) for the Calvert Cliffs Nuclear Power Plant2. NE! 99-01 AG1February 201659EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexF::Alnn Nucrlear...................... m m Category:R -Abnormal Rad Release /Rad EffluentSubcategory: 2 -Onsite Rad Conditions & Spent Fuel EventsInitiating Condition: Unplanned rise in plant radiation levelsEAL:RU2.1 Unusual EventUNPLANNED water level drop in a reactor refueling pathway as indicated by ANY of thefollowing (Note 3):* Inability to restore and maintain SEP level > Technical Specification limit (65 ft 7 in)* Inability to restore and maintain REP level > Technical Specification limit (56 ft 8.5in)* Report of visual observation of an uncontrolled drop in water level in the REP orSEPANDArea radiation monitor reading rise on ANY of the following:* SEP Area RM-320 EL-69 (0RIC-7023 Channel 4)* Spent Fuel Handling Machine (0RIC-7023 Channel 3)* Unit 1/2 CNTMT EL-69 (RI-53I6A/B/C/D)EALs CU3.1, CU3.2 or CU3.3Mode Applicability:AllBasis:GenericThis EAL addresses increased radiation levels as a result of water level decreases aboveirradiated fuel or events that have resulted, or may result, in unplanned increases in radiation doserates within plant buildings. These radiation increases represent a loss of control over radioactivematerial and represent a potential degradation in the level of safety of the plant.The refueling pathway is a combination of cavities, tubes, canals and pools. While a radiationmonitor could detect an increase in dose rate due to a drop in the water level, it might not be areliable indication of whether or not the fuel is covered.For refueling events where the water level drops below the RPV flange classification would be viaEAL CU3.1, CU3.2 or CU3.3. This event escalates to an Alert per EAL RA2.1 if irradiated fueloutside the reactor vessel is uncovered. For events involving irradiated fuel in the reactor vessel,escalation would be via the Fission Product Barrier Table for events in operating modes 1-4.February 201660EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearPlant-SpecificThe reactor refueling pool (REP), spent fuel pool (SEP) and fuel transfer canal comprise therefueling pathway.The Spent Fuel Pool (SFP) is normally filled with borated water to a level of 67 ft. The SEP isequipped with a level switch in each half that actuates a low level alarm at 66 ft 6 in. The minimumlevel per Technical Specifications is 65 feet, 8.5 inches (21 feet, 6 inches above the fuel seated inthe SFP) (ref. 6). The phrase "... inability to restore and maintain.., level >..." allows the operator tovisually observe the low water level condition, if possible, and to attempt water level restorationinstructions as long as water level remains above the top of irradiated fuel.When the fuel transfer canal is directly connected to the spent fuel pool and refueling pool, therecould exist the possibility of uncovering irradiated fuel in the fuel transfer canal. Therefore, this EALis applicable to cold conditions in which irradiated fuel is being transferred to and from the ReactorVessel and refueling pool. In hot conditions, the refueling pool is empty and this EAL would applyto irradiated fuel in the spent fuel pool.Technical Specifications requires that refueling pool water level be maintained 23 ft aboveirradiated fuel seated in the Reactor Vessel when moving fuel.While a radiation monitor could detect a rise in dose due to a drop in the water level, it might not bea reliable indication, in and of itself, of whether or not the fuel is uncovered. For example, thereading on an area radiation monitor located on the refueling bridge may rise due to plannedevolutions such as head lift, or even a fuel assembly being raised in the manipulator mast.Elevated radiation monitor indications will need to be combined with another indicator (orpersonnel report) of water loss.This event escalates to an Alert if irradiated fuel outside the reactor vessel is uncovered.Definitions:UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.February 2016 61 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelnn NuclIearCCNPP Basis Reference(s):1. AOP-6E Loss of Refueling Pool Level2. System Description No. 67/68 Spent Fuel Pool and Cooling System3. Shutdown Safety Surveillance H (Fuel Movement Observation)4. Technical Specifications Section 3.9.6 Refueling Pool Water Level5. Technical Specifications Section 3.7.13 SEP Water Level7. TS-05.O1 Technical Specification Action Value Bases Document8. NEI 99-01 AU2February 201662EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexE~I~xnn NiitIlz~r...................... B m iNvmvMmCategory:Subcategory:R -Radioactivity Release / Area Radiation2 -Onsite Rad Conditions & Spent Fuel EventsInitiating Condition: Unplanned rise in plant radiation levelsEAL:RU2.2 Unusual EventUNPLANNED area radiation readings increases by a factor of 1,000 over NORMAL LEVELSMode Applicability:AllBasis:GenericThis EAL addresses increased radiation levels as a result of water level decreases aboveirradiated fuel or events that have resulted, or may result, in unplanned increases in radiation doserates within plant buildings. These radiation increases represent a loss of control over radioactivematerial and represent a potential degradation in the level of safety of the plant.This EAL addresses increases in plant radiation levels that represent a loss of control ofradioactive material resulting in a potential degradation in the level of safety of the plant.This EAL excludes radiation level increases that result from planned activities such as use ofradiographic sources and movement of radioactive waste materials. A specific list of ARMs is notrequired as it would restrict the applicability of the threshold. The intent is to identify loss of controlof radioactive material in any monitored area.Plant-SpecificAssessment of this EAL may be made with survey readings using portable instruments as well asinstalled radiation monitors.Definitions:UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.Normal LevelsAs applied to radiological IC/EALs, the highest reading in the past twenty-four hours excludingthe current peak value.CCNPP Basis Reference(s):1. NEI 99-01 AU2February 201663EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:R -Abnormal Rad Release / Rad Effluent2 -Onsite Rad Conditions & Spent Fuel EventsInitiating Condition: Damage to irradiated fuel or loss of water level that has resulted orwill result in the uncovering of irradiated fuel outside the ReactorVesselEAL:RA2.1 AlertAlarm on ANY of the following radiation monitors due to damage to irradiated fuel or lossof water level:* Fuel Handling Area Vent (RI-5420)* SEP Area RM-320 EL-69 (0RIC-7023 Channel 4)* Spent Fuel Handling Machine (0RIC-7023 Channel 3)* Unit 1/2 CNTMT EL-69 (RI-5316AIBICID)Mode Applicability:AllBasis:GenericThis EAL addresses increases in radiation dose rates within plant buildings, and may be aprecursor to a radioactivity release to the environment. These events represent a loss of controlover radioactive material and represent an actual or substantial potential degradation in the level ofsafety of the plant.This EAL addresses radiation monitor indications of fuel uncovery and/or fuel damage.Increased ventilation monitor readings may be indication of a radioactivity release from the fuel,confirming that damage has occurred. Increased background at the ventilation monitor due towater level decrease may mask increased ventilation exhaust airborne activity and needs to beconsidered.While a radiation monitor could detect an increase in dose rate due to a drop in the water level, itmight not be a reliable indication of whether or not the fuel is covered.Escalation of this emergency classification level, if appropriate, would be based on RS1.1, RS1.2,RS1.3, RGI.1, RGI.2 or RG1.3.Plant-SpoecificThis EAL is defined by the specific areas where irradiated fuel is located such as the refueling pool,reactor vessel, or spent fuel pool.February 201664EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearThe bases for the area radiation high alarms and Containment radiation high alarms are a spentfuel handling accident and are, therefore, appropriate for this EAL. Elevated readings on ventilationmonitors may also be indication of a radioactivity release from the fuel, confirming that damage hasoccurred. However, elevated background at the monitor due to water level lowering may maskelevated ventilation exhaust airborne activity and needs to be considered. However, while radiationmonitors may detect a rise in dose rate due to a drop in the water level, it might not be a reliableindication of whether or not the fuel is covered. The following are examples of events in which themonitor could be responding properly yet not signaling damage to or uncovery of irradiated fueloutside the reactor vessel:* Transfer or relocation of a source stored in or near the fuel pool.* A planned evolution such as removal of the reactor head.* Movement of spent fuel with fuel rods that have been known to be leaking.Interpretation of these EAL thresholds requires some understanding of the actual radiologicalconditions present in the vicinity of the monitors.CCNPP Basis Reference(s):1. 1I(2)AOP-6E Loss of Refueling Pool Level2. OP-07 Shutdown Operations, Section 6.9.B Checklist for Fuel Movement"3. NEI 99-01 AA2February 201665EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:Initiating Condition:R -Abnormal Rad Release / Rad Effluent2 -Onsite Rad Conditions & Spent Fuel EventsDamage to irradiated fuel or loss of water level that has resulted orwill result in the uncovering of irradiated fuel outside the ReactorVesselEAL:Mode Applicability:AllBasis:GenericThis event represents a loss of control over radioactive material and represent an actual orsubstantial potential degradation in the level of safety of the plant.Escalation of this emergency classification level, if appropriate, would be based on RS1.1, RSI.2,RS1.3, RGI.1, RG1.2 or RG1.3.Plant-SpecificThis EAL is defined by the specific areas where irradiated fuel is located such as the refueling pool,Reactor Vessel or Spent Fuel Pool.There is no direct indication that water level in the Spent Fuel Pool or refueling pool has dropped tothe level of the fuel other than visual observation. Since there is no level indicating system in thefuel transfer canal, visual observation of loss of water level would also be required. If available,video cameras may allow remote observation. Depending on available level indication, thedeclared threshold may need to be based on indications of makeup rate or lowering in RefuelingWater Storage Tank level (ref. 1).The movement of irradiated fuel assemblies within Containment requires a minimum water level of23 ft above the Reactor Vessel flange and the top of spent fuel in the SEP. During refuelingactivities, this maintains sufficient water level in the refueling cavity, fuel transfer canal and SEP.Sufficient water is necessary to retain iodine fission product activity in the water in the event of afuel handling accident (ref. 2, 3).February 201666EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearAllowing level to decrease could result in spent fuel being uncovered, reducing spent fuel decayheat removal and creating an extremely hazardous radiation environment.CCNPP Basis Reference(s):1. 1(2) AOP-6E Loss of Refueling Pool Level2. Technical Specifications Section 3.9.6 Refueling Pool Water Level3. Technical Specifications Section 3.7.13 SFP Water Level4. NEI 99-01 AA2February 201667EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:R -Abnormal Rad Release / Rad Effluent3 -CR/CAS RadInitiating Condition: Rise in radiation levels within the facility that impedes operation ofsystems required to maintain plant safety functionsEAL:RA3.1 AlertDose rates > 15 mRem/hr in ANY of the following areas requiring continuous occupancy tomaintain plant safety functions:* Control Room* CASMode Applicability:AllBasis:GenericThis EAL addresses increased radiation levels that: impact continued operation in areas requiringcontinuous occupancy to maintain safe operation or to perform a safe shutdown.The cause and/or magnitude of the increase in radiation levels is not a concern of this EAL. TheEmergency Director must consider the source or cause of the increased radiation levels anddetermine if any other EAL may be involved.Areas requiring continuous occupancy include the Control Room and any other control stationsthat are staffed continuously, such as the security alarm station CAS.Plant-SpecificThe Control Room and Central Alarm Station (CAS) must be continuously occupied in all plantoperating modes at CCNPP.There is no area radiation monitoring system at CCNPP for the Control Room or CAS. Abnormalradiation levels may be initially detected by the Control Room vent supply radiation monitor, routineradiological surveys and abnormal responses from electronic personnel dosimeters worn bypersonnel occupying these spaces.CCNPP Basis Reference(s):1. System Description # 77/79 Radiation Monitoring System2. UFSAR Section 11.2.2.5 Auxiliary Building Shielding3. NEI 99-01 AA3February 201668EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory E -Independent Spent Fuel Storage Installation (ISFSIIDSC)EAL Group: Not Applicable (the EAL in this category isapplicable independent of plant operating mode)An independent spent fuel storage installation (ISESI) is a complex that is designed andconstructed for the interim storage of spent nuclear fuel and other radioactive materials associatedwith spent fuel storage. A significant amount of the radioactive material contained within acask/canister must escape its packaging and enter the biosphere for there to be a significantenvironmental effect resulting from an accident involving the dry storage of spent nuclear fuel.Formal offsite planning is not required because the postulated worst-case accident involving anISESI has insignificant consequences to the public health and safety.A Notification of Unusual Event is declared on the basis of the occurrence of an event of sufficientmagnitude that a loaded cask confinement boundary is damaged or violated. This includesclassification based on a loaded fuel storage cask/canister confinement boundary loss leading tothe degradation of the fuel during storage or posing an operational safety problem with respect toits removal from storage.A hostile security event that leads to a potential loss in the level of safety of the ISESI is aclassifiable event under Security category EAL HA4. 1.Minor surface damage that does not affect storage cask/canister boundary is excluded from thescope of these EALs.February 201669EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: E -ISFSI/DSCSubcategory: Not ApplicableInitiating Condition: Damage to a loaded cask confinement boundaryEAL:EUI.1 Unusual EventDamage to a loaded cask CONFINEMENT BOUNDARYMode Applicability:Not applicableBasis:GenericAn UE in this EAL is categorized on the basis of the occurrence of an event of sufficient magnitudethat a loaded cask confinement boundary is damaged or violated. This includes classificationbased on a loaded fuel storage cask confinement boundary loss leading to the degradation of thefuel during storage or posing an operational safety problem with respect to its removal fromstorage.This EAL addresses a dropped cask, a tipped over cask, EXPLOSION, PROJECTILE damage,FIRE damage or natural phenomena affecting a cask (e.g., seismic event, tornado, etc.).Plant-SpecificThe CCNPP ISESI utilizes the NUHOMS dry spent fuel storage system.This EAL addresses any condition which indicates a loss of a cask confinement boundary and thusa potential degradation in the level of safety of the ISESI. The cask confinement boundary isconsidered the Dry Shielded Canister (DSC).Definitions:Confinement BoundaryThe barrier(s) between areas containing radioactive substances and the environment.Independent Spent Fuel Storage Installation (ISFSI)A complex that is designed and constructed for the interim storage of spent nuclear fuel andother radioactive materials associated with spent fuel storage.CCNPP Basis Reference(s):1. Calvert Cliffs ISESI USAR2. NEI 99-01 E-HU1February 2016 70 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory C -Cold Shutdown I Refueling System MalfunctionEAL Group: Cold Conditions (RCS temperature -< 200°F); EALsin this category are applicable only in one or morecold operating modes.Category C EALs are directly associated with cold shutdown or refueling system safety functions.Given the variability of plant configurations (e.g., systems out-of-service for maintenance,Containment open, reduced AC power redundancy, time since shutdown) during these periods, theconsequences of any given initiating event can vary greatly. For example, a loss of decay heatremoval capability that occurs at the end of an extended outage has less significance than a similarloss occurring during the first week after shutdown. Compounding these events is the likelihoodthat instrumentation necessary for assessment may also be inoperable. The cold shutdown andrefueling system malfunction EALs are based on performance capability to the extent possible withconsideration given to RCS integrity, Containment closure, and fuel clad integrity for the applicableoperating modes (5 -Cold Shutdown, 6 -Refuel, 0 -Defueled).The events of this category pertain to the following subcategories:1. Loss of AC PowerLoss of emergency plant electrical power can compromise plant safety system operabilityincluding decay heat removal and emergency core cooling systems which may be necessary toensure fission product barrier integrity. This category includes loss of onsite and offsite powersources for the 4 kV safeguard buses.2. Loss of DC PowerLoss of emergency plant electrical power can compromise plant safety system operabilityincluding decay heat removal and emergency core cooling systems which may be necessary toensure fission product barrier integrity. This category includes loss of power to the 125 VDCbuses.February 2016 71 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclear3. ROS LevelReactor Vessel or RCS water level is directly related to the status of adequate core coolingand, therefore, fuel clad integrity. RCS levels associated with Category C EALs are listed inTable 0-5.4. RCS TemperatureUncontrolled or inadvertent temperature or pressure increases are indicative of a potential lossof safety functions.5. CommunicationsCertain events that degrade plant operator ability to effectively communicate with essentialpersonnel within or external to the plant warrant emergency classification.6. Inadvertent CriticalityInadvertent criticalities pose potential personnel safety hazards as well being indicative oflosses of reactivity control.February 201672EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:C -Cold Shutdown / Refueling System MalfunctionSubcategory: 1 -Loss of AC PowerInitiating Condition: AC power capability to 4kV vital buses reduced to a single powersource for 15 min. such that ANY additional single failure wouldresult in a complete loss of all 4kV vital bus powerEAL:CUI.1 Unusual EventAC power capability to 4kV vital buses 11(21) and 14(24) reduced to a single powersource, Table C-I, for_> 15 min. (Note 4)ANDANY additional single power source failure will result in a complete loss of all 4kV vital buspowerNote 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time.Table C-I AC Power Sources* 1(2)A DG"n

• 1(2)B DG0 0C DG, if aligned* 500kV transmission line 5051** 500kV transmission line 5052** a 500kV transmission line 5072*O

• SMECO line ,if aligned* A credited 500kV line must have anindependent 13kV service transformerMode Applicability:5 -Cold Shutdown, 6 -Refuel, D -DefueledBasis:GenericThe condition indicated by this EAL is the degradation of the off-site and on-site AC power systemssuch that any additional single failure would result in a complete loss of 4 kV vital bus AC power toone or both units. This condition could occur due to a loss of off-site power with a concurrent failureFebruary 201673EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearof all but one emergency generator to supply power to its emergency bus. The subsequent loss ofthis single power source would escalate the event to an Alert in accordance with EAL CA1 .1.Fifteen minutes was selected as a threshold to exclude transient or momentary losses of power.Plant-SpecificCCNPP essential buses are 4kV vital buses 11 (21) and 14(24). There are five offsite powersources available to these buses:*Three 500kV transmission lines (Lines 5051, 5052, and 5072) supply offsite power to the500kV switchyard via the transmission network.oOne 69kV/1 3kV Southern Maryland Electric Cooperative (SMECO) line may be manuallyconnected to either 13kV bus and then to the 4kV vital buses. Under certain operationalconditions, 13kV bus(es) may be receiving power from SMECO or may be quicklyconnected to the SMECO tie-line. The SMECO line is not used to carry loads for anoperating unit and may provide power to no more than two 4kV vital buses simultaneously.oIf a fault affects only one unit, power may be obtained from the 500kV supply of theunaffected unit through a single 13kV transformer. This is considered an offsite AC powersource available to the affected unit.Based on operational experience, if the SMECO line or the 0C DG is not already aligned, thesecannot be considered available/capable of supplying the bus due to the time it will take to alignthem. In any case, if this cannot be accomplished within 15 minutes, they are not available and anUnusual Event must be declared.In-house power is fed back from the 500KV ring bus through 2 13kV transformers (designated P-13000-1 and P-i13000-2). Normally P-i13000-1 supplies all of Unit -1 (except 14 4kV bus) and 214kV bus. P-i13000-2 supplies all of Unit-2 (except 21 4kV bus) and 14 4kV bus. Either P-i13000 iscapable of supplying all loads on both Units.February 2016 74 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Annex.... V .............. B i I There are five onsite AC power sources:* 1A DG for bus11* 1B DG for busl14* 2A DG for bus 21* 2B DG for bus 24* 00 DG may be aiigned to any vital 4kV bus on either unit.The fifteen-minute interval was selected as a threshold to exclude transient power losses. Ifmultiple sources fail to energize the unit safety-related buses within 15 minutes, an Unusual Eventis declared under this EAL. The subsequent loss of the single remaining power source escalatesthe event to an Alert under EAL CA1 .1.CCNPP Basis Reference(s):1. UFSAR Section 8 and Figure 8-12. Technical Specifications LCO 3.8.2 AC Sources-Shutdown3. Technical Specifications LCO 3.8.10 Distribution Systems-Shutdown4. 0I-21lA-1 1A Diesel Generator5. OI-21A-2 2A Diesel Generator6. OI-21B-1 lB Diesel Generator7. OI-21B-2 2B Diesel Generator8. 0I-21C 00 Diesel Generator9. STP-O-90 AC Sources and On-site Power Distribution Systems 7 Day Operability Verification10. AOP-71 Loss of 4kV, 480 Volt, or 208/120 Volt Instrument Bus Power11. AOP-3F Loss of Off-site Power While in MODES 3, 4, 5, or 612. EOP-2 Loss of Off-site Power13. NEI 99-01 CU3February 201675EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Su bcategory:C -Cold Shutdown / Refueling System Malfunction1 -Loss of AC PowerInitiating Condition: Loss of all offsite and all onsite AC power to 4kV vital buses for >15 min.EAL:CA1.1 AlertLoss of all offsite and all onsite AC power, Table C-I, to 4kV vital buses 11(21) and 14(24)for _> 15 min. (Note 4)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time.Table C-I AC Power Sources* 1(2)A DGa 1(2)B DG* 0C DG, if aligned* 500kV transmission line 5051* 500kV transmission line 5052*41 500kV transmission line 5072o

• SMECO line, if aligned* A credited 500kV line must have anindependent 13kV service transformerMode Applicability:5 -Cold Shutdown, 6 -Refuel, D -DefueledBasis:GenericLoss of all AC power compromises all plant safety systems requiring electric power including RHR,ECCS, Containment Heat Removal, Spent Fuel Heat Removal and the Ultimate Heat Sink.The event can be classified as an Alert when in cold shutdown, refuel, or defueled mode becauseof the significantly reduced decay heat and lower temperature and pressure, increasing the time torestore one of the emergency busses, relative to that specified for the Site Area Emergency EAL.Escalating to Site Area Emergency, if appropriate, is by EALs in Category R.February 201676EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearFifteen minutes was selected as a threshold to exclude transient or momentary power losses.Plant-SpoecificThe CCNPP vital buses are 4kV buses 11 (21) and 14(24). There are five offsite power sourcesavailable to these buses:* Three 500kV transmission lines (Lines 5051, 5052, and 5072) supply offsite power to the500kV switchyard via the transmission network.*One 69kV/1 3kV Southern Maryland Electric Cooperative (SMECO) line may be manuallyconnected to either vital 13kV bus and then to the 4kV vital buses. Under certainoperational conditions, 13kV bus(es) may be receiving power from SMECO or may bequickiy connected to the SMECO tie-line. The SMECO line is not used to carry loads for anoperating unit and may provide power to no more than two 4kV vital buses simultaneously.*If a fault affects only one unit, power may be obtained from the 500kV supply of theunaffected unit through a single 13 kV transformer. This is considered an offsite AC powersource available to the affected unit.In-house power is fed back from the 500kV ring bus through 2 13kV transformers (designated P-13000-1 and P-i13000-2). Normally P-i13000-1 supplies all of Unit -I (except 14 4kV bus) and 214kV bus. P-I13000-2 supplies all of Unit-2 (except 21 4kV bus) and 14 4kV bus. Either P-13000 iscapable of supplying all loads on both Units.There are five onsite AC power sources:* 1A DG for bus11* 1B DGforbusl14* 2A DG for bus 21* 2B DG for bus 24* OC DG may be aligned to any vital 4kV bus on either unit.Based on operational experience, if the SMECO line or the OC DG is not already aligned, thesecannot be considered available/capable of supplying the bus due to the time it will take to alignthem. In any case, if this cannot be accomplished within 15 minutes, they are not available and anAlert must be declared.February 2016 77 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearConsideration should be given to operable loads necessary to remove decay heat or provideReactor Vessel makeup capability when evaluating loss of all AC power to vital buses. Eventhough an essential bus may be energized, if necessary loads (i.e., loads that if lost would inhibitdecay heat removal capability or Reactor Vessel makeup capability) are not operable on theenergized bus then the bus should not be considered operable.The fifteen-minute interval was selected as a threshold to exclude transient power losses. If the 0CDG is available but is not powering a vital bus within 15 minutes, the EAL remains applicable.This EAL is the cold condition equivalent of the hot condition loss of all AC power EAL SS1.1.CCNPP Basis Reference(s):1. UFSAR Section 8 and Figure 8-12. Technical Specifications LCO 3.8.2 AC Sources-Shutdown3. Technical Specifications LCO 3.8.10 Distribution Systems-Shutdown4. 0I-21lA-1 IA Diesel Generator5. Ol-21A-2 2A Diesel Generator6. Ol-21B-1 lB Diesel Generator7. 0I-21 B-2 2B Diesel Generator8. 0I-21C 00 Diesel Generator9. STP-O-90 AC Sources and On-site Power Distribution Systems 7 Day Operability Verification10. AOP-71 Loss of 4kV, 480 Volt, or 208/120 Volt Instrument Bus Power11. AOP-3F Loss of Off-site Power While in MODES 3, 4, 5, or 612. EOP-2 Loss of Off-site Power13. EOP-7 Station Blackout14. EOP-8 Functional Recovery15. NEI 99-01 CA3February 2016 78 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: C -Cold Shutdown / Refueling System MalfunctionSubcategory: 2 -Loss of DC PowerInitiating Condition: Loss of required DC power for> 15 min.EAL:CU2.1 Unusual Event< 105 VDC for_ 15min. on the 125 VDC buses (11, 12, 21 or 22) that are required tomonitor and control the removal of decay heat (Note 4)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time.Mode Applicability:5 -Cold Shutdown, 6 -RefuelBasis:GenericThe purpose of this EAL is to recognize a loss of DC power compromising the ability to monitor andcontrol the removal of decay heat during Cold Shutdown or Refueling operations.Fifteen minutes was selected as a threshold to exclude transient or momentary power losses.Plant-Sp~ecificThe 125 VDC vital system is divided into four independent and isolated channels. Each channelconsists of one battery, two battery chargers, one DC bus, multiple DC unit control panels, and twoinverters. Each inverter has an associated vital AC distribution panel board. Power to the DC bus,DC unit control panels, and inverters is supplied by the station batteries and/or the batterychargers. Each battery charger is fully rated and can recharge a discharged battery while at thesame time supplying the steady state power requirements of the system. A reserve 125 VDCsystem for the plant is completely independent and isolated from all four separation groups, yet iscapable of replacing any of the 125 VDC batteries. This system consists of one battery, one batterycharger, and the associated DC switching equipment. Only the battery may be transferred forreplacement duty.The safety-related station batteries have been sized to carry their expected shutdown loadsfollowing a plant trip/LOCA and loss of offsite power or following a station blackout without batteryterminal voltage falling below 105 volts. The fifteen-minute interval was selected as a threshold toFebruary 2016 79 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclearexclude transient or momentary power losses. The loss of the 1A Diesel Generator 125 VDC bus14 or 00 Diesel Generator bus 16 does not constitute an entry condition for this EAL.Maintenance on a DC bus may be performed periodically during shutdown conditions. The"required" 125 VDC buses signifies the minimum allowed by Technical Specifications for the modeof operation (Refer to Technical Specification 3.8.10 for required 1 25V DC Buses). If loss of the"required" bus results in the inability to maintain cold shutdown, consideration should be given toescalation to an Alert under EAL CA4. 1.CCNPP Basis Reference(s):1. UFSAR Section 8.4.3 and Figure 8.92. EOP-0 Post-Trip Immediate Actions3. EOP-2 Loss of Off-Site Power, Section V4. AOP-7J Loss of 120 Volt Vital AC or 125 Volt Vital DC Power5. Technical Specifications Bases 3.8.106. NEI 99-01 CU7February 201680EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: C -Cold Shutdown I Refueling System MalfunctionSubcategory: 3 -RCS LevelInitiating Condition: RCS leakageEAL:CU3.1 Unusual EventRCS leakage results in the inability to maintain or restore EITHER of the following for>_15mrai. (Note 4):Pressurizer level > 101 in.ORRCS level within the target band established by procedure (when the level band wasestablished below 101 in.)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable timeMode Applicability:5 -Cold ShutdownBasis:GenericThis EAL is considered to be a potential degradation of the level of safety of the plant. The inabilityto maintain or restore level is indicative of loss of RCS inventory.Relief valve normal operation should be excluded from this EAL. However, a relief valve thatoperates and fails to close per design should be considered applicable to this EAL if the relief valvecannot be isolated.Prolonged loss of RCS inventory may result in escalation to the Alert emergency classification levelvia either EAL CA4.1 or EAL CA3.1.Plant-SpecificWhen pressurizer level drops to 101 in., pressurizer heaters are deenergized. This condition issignaled by annunciator 1006-ALM Window E-35, PZR HTR CUTOFF.In Cold Shutdown mode, pressurizer level may be intentionally lowered below the heater cutoffsetpoint (e.g., in preparation to detension the reactor vessel head, etc.). For such evolutions, thisEAL is applicable if RCS level cannot be restored and maintained within the prescribed target bandspecified by procedure.February 2016 81 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCCNPP Basis Reference(s):1. 1 C06-ALM Window E-35, PZR HTR CUTOFF2. AOP-2, Excessive Reactor Coolant Leakage3. UFSAR 7.4.44. NEI 99-01 CU1February 201682EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryAnncwvvI::ln n Nuna-Il~rk Category:Subcategory:C -Cold Shutdown / Refueling System Malfunction3 -RCS LevelInitiating Condition: RCS LeakageEAL:CU3.2 Unusual EventUNPLANNED RCS level drop below EITHER of the following for - 15 min. (Note 4):Reactor Vessel flange (44 ft) (when the level band was established above the flange)ORTarget band (when the level band was established below the flange)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable timeMode Applicability:6 -RefuelBasis:GenericThis EAL is a precursor of more serious conditions and considered to be a potential degradation ofthe level of safety of the plant.Refueling evolutions that decrease RCS water level below the Reactor Vessel flange are carefullyplanned and procedurally controlled. An unplanned event that results in water level decreasingbelow the Reactor Vessel flange, or below the planned RCS water level for the given evolution (ifthe planned RCS water level is already below the Reactor Vessel flange), warrants declaration of aUE due to the reduced ROS inventory that is available to keep the core covered.The allowance of 15 minutes was chosen because it is reasonable to assume that level can berestored within this time frame using one or more of the redundant means of refill that should beavailable. If level cannot be restored in this time frame then it may indicate a more seriouscondition exists.Continued loss of RCS Inventory will result in escalation to the Alert emergency classification levelvia either EAL CA4.1 or EAL CA3.1.This EAL involves a decrease in RCS level below the top of the Reactor Vessel flange thatcontinues for 15 minutes due to an unplanned event. This EAL is not applicable to decreases inflooded reactor cavity level, which is addressed by EAL RU2.1, until such time as the leveldecreases to the level of the vessel flange.February 201683EP-AA-1 011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearPlant-SpecificThe Reactor Vessel flange level is at 44 ft (43.97 ft) Refueling Pool level (ref. 2). RCS elevationsand level indication capabilities are illustrated in Attachment 15 of AOP-3B (ref. 2).Figure C-1 illustrates the RCS levels associated with Category C EALs.This EAL involves a lowering in RCS level below the top of the Reactor Vessel flange, or theinability to maintain water level above the intended level when level is being intentionallymaintained below the flange, that continues for fifteen minutes due to an unplanned event. ThisEAL is not applicable to drops in flooded refueling pool level (covered by lowering spent fuel poolwater level in EAL RU2.1) until such time as the level lowers to the level of the vessel flange. Iflevel continues to lower and reaches the bottom of the RCS Hot Leg (35.58 ft), escalation to theAlert level under EAL CA3.1 would be appropriate. If the level lowering is accompanied by RCSheatup, escalation to the Alert level under EAL CA4.1 may also be appropriate.In Cold Shutdown mode, the RCS will normally be intact and standard RCS inventory and levelmonitoring means are available. In the Refuel mode, the RCS is not intact and Reactor Vessellevel and inventory are monitored by different means. In the Refuel mode, normal means of coretemperature indication and RCS level indication may not be available. Redundant means ofReactor Vessel level indication will normally be installed (including the ability to monitor levelvisually) to assure that the ability to monitor level will not be interrupted. Reactor Vessel water levelis normally monitored using the following instruments:* Refueling Pool Level LI-4140* RCS Level Narrow Range LI-4138* RCS Level Wide Range LI-4139* Local refueling level indicator (LG-4139 and tygon tubing)* Reactor Vessel Level Monitoring System (RVLMS)If RCS water level will be below the bottom of the Pressurizer (48.5 ft el.), IM installs and calibratesthe Refueling Level Cart in the Control Room and places the RCS Wide Range Level MonitoringSystem in service (LI-41 39). The Wide Range Level High/Low alarms (LAH/L-4139) and NarrowRange Level High/Low alarms (LAH/L-41 38) are set above/below the target RCS level. As waterlevel is changed, the alarms are reset every two feet. Table 1 of OP-7, Shutdown Operations,provides a cross-reference of Refueling Pool level and RVLMS alarm lights to various plantcomponent elevations.February 2016 84 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearDefinitions:UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.CCNPP Basis Reference(s):1. AOP-2, Excessive Reactor Coolant Leakage2. AOP-3B, Abnormal Shutdown Cooling Conditions3. OP-7 Shutdown Operations4. NEI 99-01 CU2Figure C-I: RCS Levels Thresholds (ref. 2)February 201685EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:C -Cold Shutdown / Refueling System Malfunction3 -RCS LevelInitiating Condition: RCS LeakageEAL:CU3.3 Unusual EventRCS level cannot be monitored with a loss of RCS inventory as indicated by anunexplained level rise in ANY Table C-2 sump / tank attributable to RCS leakageTable C-2 RCS Leakage Indications* Containment sump* Auxiliary Building sumps* Miscellaneous Waste System Tanks* RWT* RC Waste System TankMode Applicability:6 -RefuelBasis:GenericThis EAL is a precursor of more serious conditions and considered to be a potential degradation ofthe level of safety of the plant.Refueling evolutions that decrease RCS water level below the Reactor Vessel flange are carefullyplanned and procedurally controlled. An UNPLANNED event that results in water level decreasingbelow the Reactor Vessel flange, or below the planned RCS water level for the given evolution (ifthe planned RCS water level is already below the Reactor Vessel flange), warrants declaration of aUE due to the reduced ROS inventory that is available to keep the core covered.Continued loss of ROS Inventory will result in escalation to the Alert emergency classification levelvia either EAL CA3.1 or EAL CA4.1.February 201686EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearThis EAL addresses conditions in the refueling mode when normal means of core temperatureindication and RCS level indication may not be available. Redundant means of RCS levelindication will normally be installed (including the ability to monitor level visually) to assure that theability to monitor level will not be interrupted. However, if all level indication were to be lost during aloss of RCS inventory event, the operators would need to determine that RCS inventory loss wasoccurring by observing sump and tank level changes. Sump and tank level increases must beevaluated against other potential sources of leakage such as cooling water sources inside theContainment to ensure they are indicative of RCS leakage.Plant-SpecificIn this EAL, all level indication would be unavailable and, the Reactor Vessel inventory loss mustbe detected by Containment sump, Auxiliary Building sum ps, Miscellaneous Waste System Tanks,or RWVT level changes. AOP-2A-I (2), Excessive Reactor Coolant Leakage, provides direction fordetermining RCS leakage for off normal events and for operations troubleshooting. ContainmentSump narrow range level instrumentation (LI-4144/4145) on 1C08 (2008) and 1009 (2CO9)indicate level in the Containment Emergency Sump and can be trended prior to receiving theContainment Sump Level Hi alarm. Sump and tank level increases must be evaluated againstother potential sources of leakage such as cooling water sources inside the Containment to ensurethey are indicative of RCS leakage.Definitions:UnisolableA breach or leak that cannot be promptly isolated.CCNPP Basis Reference(s):1. AOP-2A Excessive Reactor Coolant Leakage2. STP 0-27-1(2) RCS Leakage Evaluation3. NEI 99-01 CU2February 2016 87 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:C -Cold Shutdown I Refueling System Malfunction3 -RCS LevelInitiating Condition: Loss of RCS inventoryEAL:CA3.1 AlertLoss of inventory as indicated by RCS water level < 35.6 ft (29 in. 6th alarm on RVLMS)ORRCS level cannot be monitored for >_ 15 min. with a loss of RCS inventory as indicated byan unexplained level rise in ANY Table C-2 sump I tank attributable to RCS leakage(Note 4)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time.Table C-2 RCS Leakage Indications* Containment sump* Auxiliary Building sumps* Miscellaneous Waste System Tanks* RWT* RC Waste System TankMode Applicability:5 -Cold Shutdown, 6 -RefuelBasis:GenericThis EAL serves as a precursor to a loss of ability to adequately cool the fuel. The magnitude ofthis loss of water indicates that makeup systems have not been effective and may not be capableof preventing further RCS level decrease and potential core uncovery. This condition will result in aminimum emergency classification level of an Alert.The inability to restore and maintain level after reaching this setpoint would be indicative of afailure of the RCS barrier.If RCS level continues to lower then escalation to Site Area Emergency will be via EAL 0S3.1, EALCS3.2 or EAL CS3.3.February 201688EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearPlant-SpiecificFigure C-I illustrates the RCS levels associated with Category C EALs.When RCS water level lowers to 35.58 ft (rounded to 35.6 ft), the bottom of the RCS hot leg isuncovered. This level can be monitored by:* Refueling Pool Level LI-4140* RCS Level Narrow Range LI-4138* RCS Level Wide Range LI-41 39* Local refueling level indicator (LG-4139 and tygon tubing)* RVLMS (6th RVLMS Alarm [29 in.1) corresponds to 35.58 ftThis EAL serves as a precursor to a loss of ability to adequately cool the fuel. The magnitude ofthis loss of water indicates makeup systems have not been effective and may not be capable ofpreventing further RCS or Reactor Vessel level lowering and potential core uncovery. The bottomof the hot leg is the level equal to the bottom of the Reactor Vessel loop penetration, not the lowpoint of the loop. This level was chosen because remote RCS level indication may be lost and lossof suction to decay heat removal systems has occurred. The inability to restore and maintain levelafter reaching this setpoint infers a failure of the RCS barrier.In Cold Shutdown, the decay heat available to raise RCS temperature during a loss of inventory orheat removal event may be significantly greater than in the Refuel mode. Entry into Cold Shutdownmode may be attained within hours of operating at power or hours after refueling is completed.Entry into the Refuel mode may not occur for many hours after the reactor has been shutdown.Thus, the heatup and the threat to damaging the fuel clad may be lower for events that occur in theRefuel mode with irradiated fuel in the Reactor Vessel. Note that the heatup threat could be lowerfor Cold Shutdown conditions if the entry into Cold Shutdown was following a refueling.In Cold Shutdown mode, the RCS will normally be intact and standard RCS inventory and levelmonitoring means are available. In the Refuel mode, the RCS is not intact and Reactor Vessellevel and inventory are monitored by different means. In the Refuel mode, normal means of coretemperature indication and RCS level indication may not be available. Redundant means ofReactor Vessel level indication will normally be installed (including the ability to monitor levelvisually) to assure that the ability to monitor level will not be interrupted.In the second condition of this EAL, all level indication would be unavailable and, the ReactorVessel/RCS inventory loss must be detected by Containment sump, Auxiliary Building sumps,February 2016 89 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearMiscellaneous Waste System Tanks, or RWT level changes. AOP-2A-I (2), Excessive ReactorCoolant Leakage, provides direction for determining RCS leakage for off normal events and foroperations troubleshooting. Containment Sump narrow range level instrumentation (LI-4144/4145)on 1C08(2C08) and lC09(2CO9) indicate level in the Containment Emergency Sump and can betrended prior to receiving the Containment Sump Level Hi alarm. Sump level increases must beevaluated against other potential sources of leakage such as cooling water sources inside theContainment to ensure they are indicative of RCS leakage.The 15-minute interval for the loss of level indication was chosen because it is half of the Site AreaEmergency EAL duration. The interval allows this EAL to be an effective precursor to the Site AreaEmergency EAL CS3.3. Therefore this EAL meets the definition for an Alert emergency.Definitions:UnisolableA breach or leak that cannot be promptly isolated.CCNPP Basis Reference(s):1. OP-7 Shutdown Operations2. AOP-2A Excessive Reactor Coolant Leakage3. AOP-3B, Abnormal Shutdown Cooling Conditions4. STP 0-27-1(2) RCS Leakage Evaluation5. NEI 99-01 CA1February 201690EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearFigure C-I: RCS Levels Thresholds (ref. 2)February 201691EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: C -Cold Shutdown / Refueling System MalfunctionSubcategory: 3 -RCS LevelInitiating Condition: Loss of RCS inventory affecting core decay heat removal capabilityEAL:CS3.1 Site Area EmergencyWith CONTAINMENT CLOSURE not established, RCS level < 34.7 ft (19 in. 7th alarm onRVLMS)Mode Applicability:5 -Cold Shutdown, 6 -RefuelBasis:GenericUnder the conditions specified by this EAL, continued decrease in RCS level is indicative of a lossof inventory control. Inventory loss may be due to an RCS breach, pressure boundary leakage, orcontinued boiling in the RCS. Thus, declaration of a Site Area Emergency is warranted.Escalation to a General Emergency is via EAL CG3.1, EAL CG3.2, RG1.1, RG1.2 or RG1.3.Plant-SpecificFigure C-i illustrates the RCS levels associated with Category C EALs.This level can be monitored by:* Refueling Pool Level LI-4140* RCS Level Narrow Range LI-4138* RCS Level Wide Range LI-41 39* Local refueling level indicator (LG-4139 and tygon tubing)* RVLMS (7th RVLMS Alarm) corresponds to 34.74 ftWhen Reactor Vessel water level drops to 34.74 ft el. (rounded to 34.7 ft), level is ten inches belowthe bottom of the RCS hot leg vessel penetration.Under the conditions specified in this EAL, continued lowering of RCS water level is indicative of aloss of inventory control. Inventory loss may be due to a vessel breach, RCS pressure boundaryleakage or continued boiling in the Reactor Vessel. The magnitude of this loss of water indicatesthat makeup systems have not been effective and may not be capable of preventing further RCS orReactor Vessel water level lowering and core uncovery. The inability to restore and maintain levelFebruary 2016 92 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclearafter reaching this setpoint infers a failure of the RCS barrier and potential loss of the Fuel Cladbarrier.Containment Closure is the action or condition that ensures Containment and its associatedsystems, structures or components, as listed in STP O-55A, provide a functional barrier to fissionproduct release. Containment closure is initiated by the Shift Manager if plant conditions changethat could raise the risk of a fission product release as a result of a loss of decay heat removal.Containment closure requires that, upon a loss of decay heat removal, any open penetration mustbe closed or capable of being closed prior to RCS bulk boiling.Definitions:Containment ClosureThe site specific procedurally defined actions taken to secure Containment and its associatedstructures, systems, and components as a functional barrier to fission product release underexisting plant conditions. As applied to CCNPP, Containment Closure is the action or conditionthat ensures Containment and its associated systems, structures or components (SSC), aslisted in STP O-55A, provide a functional barrier to fission product release.CCNPP Basis Reference(s):1. UFSAR 7.5.92. OP-7 Shutdown Operations3. AOP-3B, Abnormal Shutdown Cooling Conditions4. ERPIP-601 Severe Accident Management Initial Diagnosis5. NO-i-i114 Containment Closure6. STP O-55A-1 (2) Containment Closure Verification7. NEI 99-01 CS1February 201693EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearFigure C-I: RCS Levels Thresholds (ref. 2)February 201694EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: C -Cold Shutdown / Refueling System MalfunctionSubcategory: 3 -RCS LevelInitiating Condition: Loss of RCS inventory affecting core decay heat removal capabilityEAL:CS3.2 Site Area EmergencyWith CONTAINMENT CLOSURE established, RCS level < 32.9 ft (10 in. alarm on RVLMS(Note 6))Note 6: The lowest RVLMS indication is the 10 In. alarm, which is 10 in. above top of active fuel. Therefore, thisindicator should only be used when a valid RFP/RCS level indication is not available.Mode Applicability:5 -Cold Shutdown, 6 -RefuelingBasis:GenericUnder the conditions specified by this EAL, continued decrease in RCS level is indicative of a lossof inventory control. Inventory loss may be due to an RCS breach, pressure boundary leakage, orcontinued boiling in the RPV. Thus, declaration of a Site Area Emergency is warranted.Escalation to a General Emergency is via EAL CG3.1, EAL CG3.2, RG1.1, RG1.2 or RG1.3.Plant-SpecificThis level can be monitored by:* Refueling Pool Level LI-4140* RCS Level Narrow Range LI-4138* RCS Level Wide Range LI-4139* Local refueling level indicator (LG-4139 and tygon tubing)* RVLMS (7th RVLMS Alarm) corresponds to 34.74 ftFigure C-i illustrates the RCS levels associated with Category C EALs.When Reactor Vessel/RCS water level drops to 32.9 ft el., core uncovery is about to occur. Thislevel is below the lowest indicated hot leg level. The closest RVLMS indication is the 10 in. alarm.Therefore, this indicator should only be used when a valid RFP/RCS level indication is notavailable.February 2016 95 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearUnder the conditions specified in this EAL, continued lowering of RCS water level is indicative of aloss of inventory control. Inventory loss may be due to a vessel breach, RCS pressure boundaryleakage or continued boiling in the Reactor Vessel. The magnitude of this loss of water indicatesthat makeup systems have not been effective and may not be capable of preventing further RCS orReactor Vessel water level lowering and core uncovery. The inability to restore and maintain levelafter reaching this setpoint infers a failure of the RCS barrier and potential loss of the Fuel Cladbarrier.Containment Closure is the action or condition that ensures Containment and its associatedsystems, structures or components, as listed in STP O-55A, provide a functional barrier to fissionproduct release. Containment closure is initiated by the Shift Manager if plant conditions changethat could raise the risk of a fission product release as a result of a loss of decay heat removal.Containment closure requires that, upon a loss of decay heat removal, any open penetration mustbe closed or capable of being closed prior to RCS bulk boiling.Definitions:Containment ClosureThe site specific procedurally defined actions taken to secure Containment and its associatedstructures, systems, and components as a functional barrier to fission product release underexisting plant conditions. As applied to CCNPP, Containment Closure is the action or conditionthat ensures Containment and its associated systems, structures or components (SSC), aslisted in STP O-55A, provide a functional barrier to fission product release.CCNPP Basis Reference(s):1. UFSAR 7.5.92. OP-7 Shutdown Operations3. AOP-3B, Abnormal Shutdown Cooling Conditions4. ERPIP-601 Severe Accident Management Initial Diagnosis5. NO-i-i114 Containment Closure6. STP O-55A-1 (2) Containment Closure Verification7. NEI 99-01 CS1February 2016 96 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexIExelon NuclearFigure C-I: RCS Levels Thresholds (ref. 2)February 201697EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory: C -Cold Shutdown / Refueling System MalfunctionSubcategory: 3 -RCS LevelInitiating Condition: Loss of RCS inventory affecting core decay heat removal capabilityEAL:CS3.3 Site Area EmergencyRCS level cannot be monitored for _ 30 main.with a loss of RCS inventory as indicated byANY of the following (Note 4):* Containment radiation > 6 R/hr* Erratic WRNI indication* Unexplained level rise in ANY Table C-2 sumnp I tank attributable to RCS leakageNote 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time.Table C-2 RCS Leakage Indications* Containment sump* Auxiliary Building sumps* Miscellaneous Waste System Tanks* RWT* RC Waste System TankMode Applicability:5 -Cold Shutdown, 6 -RefuelBasis:GenericUnder the conditions specified by this EAL, continued decrease in RCS level is indicative of a lossof inventory control. Inventory loss may be due to an RCS breach, pressure boundary leakage, orcontinued boiling in the RCS. Thus, declaration of a Site Area Emergency is warranted.Escalation to a General Emergency is via EAL CG3.1, EAL CG3.2, RG1.1, RG1.2 or RG1.3.The 30-minute duration allows sufficient time for actions to be performed to recover inventorycontrol equipment.As water level in the Reactor Vessel lowers, the dose rate above the core will increase. The doserate due to this core shine should result in site specific monitor indication and possible alarm.February 201698EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearPlant-SpecificIn Refuel or Cold Shutdown mode, normal RCS level indication (e.g., RVLMS) may be unavailablebut alternate means of level indication are normally installed (including visual observation) toassure that the ability to monitor level will not be interrupted. If all means of level monitoring are notavailable, however, the Reactor Vessel inventory loss may be detected by the following indirectmethods:*As water level in the Reactor Vessel lowers, the dose rate above the core will rise. Thedose rate due to this core shine should result in on-scale Containment radiation monitorindication and possible alarm. Containment radiation is indicated on 1(2)-RI-5317 A&B.Typical Containment radiation readings at full power are 1 to 1.2 R/hr. The Containmentradiation monitors alarm at 6 R/hr. The 6 R/hr setpoint has been selected to beoperationally significant and above that expected under normal plant conditions while in theRefuel mode.*Post-TMI studies indicated that the installed nuclear instrumentation will operate erraticallywhen the core is uncovered and that source range monitors such as Wide Range NuclearInstrumentation JI-O01, -002, -003, -004 and the Shutdown Monitor can be used as a toolfor making such determinations. Figure C-2 shows the response of the source rangemonitor during the first few hours of the TMI-2 accident. The instrument reported anincreasing signal about 30 minutes into the accident. At this time, the reactor coolant pumpswere running and the core was adequately cooled as indicated by the core outletthermocouples. Hence, the increasing signal was the result of an increasing two-phase voidfraction in the reactor core and vessel downcomer and the reduced shielding that the two-phase mixture provides to the source range monitor. Per CCNPP core damage assessmentstudies, core uncovery may be indicated when incore Rhodium neutron detectors or excorenuclear instruments indicate an output with the reactor known to be shutdown.*If water level indication is unavailable, the RCS inventory loss may be detected by sump ortank level changes (Table C-2). Procedures provide instructions for calculating primarysystem leak rate by manual or computer-based water inventory balances. Sump/tank levelincreases must be evaluated against other potential sources of leakage such as coolingwater sources inside the Containment to ensure they are indicative of RCS leakage.February 2016 99 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryC.alvcrt CliffR AnnmeFva~Inn Nii~nlzrW Vm V mRm BY m IB mm m m Definitions:UnisolableA breach or leak that cannot be promptly isolated.CCNPP Basis Reference(s):1. UFSAR 7.5.22. 0I-35 Radiation Monitoring System3. 1C10-ALM ESFAS 14 Alarm Manual, J-044. TS-76.01 RMS Area Radiation (Containment High Range) -Operable5. ERPIP-601 Severe Accident Management Initial Diagnosis6. ERPIP 602 Severe Accident Management Verification of Diagnosis7. ERPIP-800 Core Damage Assessment8. ERPIP-801 Core Damage Assessment Using Containment Radiation Dose Rates9. OP-7 Shutdown Operations10. AOP-2A Excessive Reactor Coolant Leakage11. STP 0-27-1(2) ROS Leakage Evaluation12. NEI 99-01 CS1February 2016100EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearFigure C-2: Response of the TMI-2 Source Range MeasurementDuring the First Six Hours of the Accidentc~J1~0c'JV..(I)a)C0.L..0.C3I-a)a)E1=31-jo-.~I~.I-(s~p~eop 6Ol) puooes ,!ad s],uno.,February 2016101EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:C -Cold Shutdown I Refueling System Malfunction3 -RCS LevelInitiating Condition: Loss of RCS inventory affecting fuel clad integrity withContainment challengedEAL:CG3.1 General EmergencyRCS level < 32.9 ft (10 in. alarm on RVLMS, Note 6) for _> 30 min. (Note 4)ANDANY Containment Challenge Indication, Table C-3Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time.Note 6: The lowest RVLMS indication is the 10 in. alarm, which is 10 in. above top of active fuel. Therefore, thisindicator should only be used when a valid RFP/RCS level indication is not available.Table C-3 Containment Challenge Indications* CONTAINMENT CLOSURE not established* Hydrogen concentration in Containment--- 4%* UNPLANNED rise in Containment pressureMode Applicability:5 -Cold Shutdown, 6 -RefuelBasis:GenericThis EAL represents the inability to restore and maintain RCS level to above the top of active fuelwith Containment challenged. Fuel damage is probable if RCS level cannot be restored, asavailable decay heat will cause boiling, further reducing the RCS level. With the Containmentbreached or challenged then the potential for unmonitored fission product release to theenvironment is high. This represents a direct path for radioactive inventory to be released to theenvironment. This is consistent with the definition of a GE. The GE is declared on the occurrenceof the loss or imminent loss of function of all three barriers.A number of variables can have a significant impact on heat removal capability challenging the fuelclad barrier. Examples include: mid-loop, reduced level/flange level, head in place, cavity flooded,RCS venting strategy, decay heat removal system design, vortexing pre-disposition, steamgenerator U-tube drainingFebruary 2016102EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearAnalysis indicates that core damage may occur within an hour following continued core uncoverytherefore, 30 minutes was conservatively chosen.If Containment Closure is re-established prior to exceeding the 30 minute core uncovery time limitthen escalation to General Emergency would not occur.Plant-SpecificFigure C-I illustrates the RCS levels associated with Category C EALs.When Reactor Vessel water level drops to 32.90 ft el., core uncovery is about to occur. This level isbelow the lowest indicated hot leg level. The lowest RVLMS indication is the last alarm, which is at10. in. above top of active fuel.Under the conditions specified in this EAL, continued lowering of RCS water level is indicative of aloss of inventory control. Inventory loss may be due to a vessel breach, RCS pressure boundaryleakage or continued boiling in the Reactor Vessel. The magnitude of this loss of water indicatesthat makeup systems have not been effective and may not be capable of preventing further RCS orReactor Vessel water level lowering and core uncovery. The inability to restore and maintain levelafter reaching this setpoint infers a failure of the RCS barrier and potential loss of the Fuel Cladbarrier. Fuel damage is probable if core submergence cannot be restored as available decay heatwill cause boiling and further lowers the vessel level.Three indications are associated with Containment challenges:*Containment Closure is the action or condition that ensures Containment and its associatedsystems, structures or components, as listed in STP O-55A, provide a functional barrier tofission product release. Containment closure is initiated by the Shift Manager if plantconditions change that could raise the risk of a fission product release as a result of a lossof decay heat removal. Containment closure requires that, upon a loss of decay heatremoval, any open penetration must be closed or capable of being closed prior to RCS bulkboiling.*In the early stages of a core uncovery event, it is unlikely that hydrogen buildup due to acore uncovery could result in an explosive mixture of dissolved gases in Containment.However, Containment monitoring and/or sampling should be performed to verify thisassumption. A combustible mixture can be formed when hydrogen gas concentration in theContainment atmosphere is greater than 4% by volume.February 2016 103 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclear*Unplanned Containment pressure increases are not expected during Cold Shutdown orRefuel mode. The threshold is indicative of conditions challenging containment closure.Definitions:Containment ClosureThe site specific procedurally defined actions taken to secure Containment and its associatedstructures, systems, and components as a functional barrier to fission product release underexisting plant conditions. As applied to CCNPP, Containment Closure is the action or conditionthat ensures Containment and its associated systems, structures or components (SSC), aslisted in STP O-55A, provide a functional barrier to fission product release.UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.CCNPP Basis Reference(s):1. UFSAR 7.5.92. OP-7 Shutdown Operations3. ERPIP-601 Severe Accident Management Initial Diagnosis4. ERPIP-800 Core Damage Assessment5. NO-I1-114 Containment Closure6. STP O-55A-1 (2) Containment Closure Verification7. UFSAR 7.5.88. Technical Specifications Table 3.3.10-19. OI-41A Hydrogen Recombiners10.1ICI0-ALM ESFAS 14 Alarm Manual, J-0911. ERPIP-803 Core Damage Assessment Using Hydrogen12. EOP-8 Functional Recovery Procedure13. EOP-13.02 Hydrogen Concentration 4.0%14. UFSAR 1.2.515. UFSAR 5.1.116. Operating License Amendment No. 242/DPR-53 & 216/DPR-6917. NEI 99-01 CG1February 2016 104 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/Proprietary(.-Iwrf AnncvFwce~lnn Table C-I: RCS Levels Thresholds (ref. 2)February 2016105EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory: C -Cold Shutdown / Refueling System MalfunctionSubcategory: 3 -RCS LevelInitiating Condition: Loss of Reactor Vessel inventory affecting fuel clad integrity withContainment challengedEAL:CG3.2 General EmergencyRCS level cannot be monitored with core uncovery indicated by ANY of the following for _>30 mmi. (Note 4):* Containment radiation > 6 R/hr* Erratic WRNI indication* Unexplained level rise in ANY Table C-2 sump I tank attributable to RCS leakageANDANY Containment Challenge Indication, Table C-3Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable timeTable C-2 RCS Leakage Indications* Containment sump* Auxiliary Building sumps* Miscellaneous Waste System Tanks* RWT* RC Waste System TankTable C-3 Containment Challenge Indications* CONTAINMENT CLOSURE not established* Hydrogen concentration in Containment - 4%* UNPLANNED rise in Containment pressureMode Applicability:5 -Cold Shutdown, 6 -RefuelFebruary 2016106EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBasis:GenericThis EAL represents the inability to restore and maintain RCS level to above the top of active fuelwith Containment challenged. Fuel damage is probable if RCS level cannot be restored, asavailable decay heat will cause boiling, further reducing the RCS level. With the Containmentbreached or challenged then the potential for unmonitored fission product release to theenvironment is high. This represents a direct path for radioactive inventory to be released to theenvironment. This is consistent with the definition of a GE. The GE is declared on the occurrenceof the loss or imminent loss of function of all three barriers.A number of variables can have a significant impact on heat removal capability challenging the fuelclad barrier. Examples include: mid-loop, reduced level/flange level, head in place, cavity flooded,RCS venting strategy, decay heat removal system design, vortexing pre-disposition, steamgenerator U-tube drainingAnalysis indicates that core damage may occur within an hour following continued core uncoverytherefore, 30 minutes was conservatively chosen.If Containment Closure is re-established prior to exceeding the 30 minute core uncovery time limitthen escalation to General Emergency would not occur.Sump and tank level increases must be evaluated against other potential sources of leakage suchas cooling water sources inside the Containment to ensure they are indicative of RCS leakage.As water level in the RCS lowers, the dose rate above the core will increase. The dose rate due tothis core shine should result in site specific monitor indication and possible alarm.Post-TMI studies indicated that the installed nuclear instrumentation will operate erratically whenthe core is uncovered and that this should be used as a tool for making such determinations.Plant-SpecificIn Refuel or Cold Shutdown mode, normal RCS level indication (e.g., RVLMS) may be unavailablebut alternate means of level indication are normally installed (including visual observation) toassure that the ability to monitor level will not be interrupted. If all means of level monitoring are notavailable, however, the Reactor Vessel inventory loss may be detected by the following indirectmethods:*As water level in the Reactor Vessel lowers, the dose rate above the core will rise. Thedose rate due to this core shine should result in on-scale Containment radiation monitorindication and possible alarm. Containment radiation is indicated on 1(2)-RI-5317 A&B.Typical Containment radiation readings at full power are 1 to 1.2 R/hr. The Containmentradiation monitors alarm at 6 R/hr. The 6 R/hr setpoint has been selected to beFebruary 2016 107 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuc:learoperationally significant and above that expected under normal plant conditions while in theRefuel mode.*Post-TMI studies indicated that the installed nuclear instrumentation will operate erraticallywhen the core is uncovered and that source range monitors such as Wide Range NuclearInstrumentation JI-001, -002, -003, -004 and the Shutdown Monitor can be used as a toolfor making such determinations. Figure 0-2 shows the response of the source rangemonitor during the first few hours of the TMI1-2 accident. The instrument reported anincreasing signal about 30 minutes into the accident. At this time, the reactor coolant pumpswere running and the core was adequately cooled as indicated by the core outletthermocouples. Hence, the increasing signal was the result of an increasing two-phase voidfraction in the reactor core and vessel downcomer and the reduced shielding that the two-phase mixture provides to the source range monitor. Per CCNPP core damage assessmentstudies, core uncovery may be indicated when incore Rhodium neutron detectors or excorenuclear instruments indicate an output with the reactor known to be shutdown.*If water level indication is unavailable, the RCS inventory loss may be detected by sump ortank level changes (Table 0-2). Procedures provide instructions for calculating primarysystem leak rate by manual or computer-based water inventory balances. Sump/tank levelincreases must be evaluated against other potential sources of leakage such as coolingwater sources inside the Containment to ensure they are indicative of RCS leakage.Three indications are associated with Containment challenges:*Containment Closure is the action or condition that ensures Containment and its associatedsystems, structures or components, as listed in STP O-55A, provide a functional barrier tofission product release. Containment closure is initiated by the Shift Manager if plantconditions change that could raise the risk of a fission product release as a result of a lossof decay heat removal. Containment closure requires that, upon a loss of decay heatremoval, any open penetration must be closed or capable of being closed prior to RCS bulkboiling.*In the early stages of a core uncovery event, it is unlikely that hydrogen buildup due to acore uncovery could result in an explosive mixture of dissolved gases in Containment.However, Containment monitoring and/or sampling should be performed to verify thisFebruary 2016 108 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearassumption. A combustible mixture can be formed when hydrogen gas concentration in theContainment atmosphere is greater than 4% by volume.*Unplanned Containment pressure increases are not expected during cold shutdown orrefuel mode. The threshold is indicative of conditions challenging Containment closure.Definitions:Containment ClosureThe site specific procedurally defined actions taken to secure Containment and its associatedstructures, systems, and components as a functional barrier to fission product release underexisting plant conditions. As applied to CCNPP, Containment Closure is the action or conditionthat ensures Containment and its associated systems, structures or components (SSC), aslisted in STP O-55A, provide a functional barrier to fission product release.UnisolableA breach or leak that cannot be promptly isolated.UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.CCNPP Basis Reference(s):I. UFSAR 7.5.92. ERPIP-601 Severe Accident Management Initial Diagnosis3. ERPIP-800 Core Damage Assessment4. NO-I-I114 Containment Closure5. STP O-55A-I1(2) Containment Closure Verification6. UFSAR 7.5.87. Technical Specifications Table 3.3.10-I8. Ol-41A Hydrogen Recornbiners9. 1C1O-ALM ESFAS 14 Alarm Manual, J-0910. ERPIP-B03 Core Damage Assessment Using HydrogenII. EOP-8 Functional Recovery Procedure12. EOP-1 3.02 Hydrogen Concentration 4.0%13. UFSAR 1.2.514. UFSAR 5.1.115. Operating License Amendment No. 242/DPR-53 & 216/DPR-6916. NEI 99-01 CGIFebruary 2016 109 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexMm ...... ......... I=A YJI K 1* I Figure C-2: Response of the TMI-2 Source Range MeasurementDuring the First Six Hours of the Accident (ref. 10, 11)CjO000CBI-I-0E1=(0D(sepeoap 6oi) puooes Jied slunooEP-AA-1011 Addendum 3(Revision 1)February 2016110 Exelon Confidential/ProprietaryC_,,h,-r$ r~liffQ Ann,-vI~vInn NulrIl2r5 Vlllltml Category:Subcategory:C -Cold Shutdown / Refueling System Malfunction4 -RCS TemperatureInitiating Condition: Unplanned loss of decay heat removal capabilityEAL:CU4.1 Unusual EventUNPLANNED event results in RCS temperature > 200°FMode Applicability:5 -Cold Shutdown, 6 -RefuelBasis:GenericThis EAL is a precursor of more serious conditions and, as a result, is considered to be a potentialdegradation of the level of safety of the plant. In cold shutdown the ability to remove decay heatrelies primarily on forced cooling flow. Operation of the systems that provide this forced coolingmay be jeopardized due to the unlikely loss of electrical power or RCS inventory. Since the RCSusually remains intact in the cold shutdown mode a large inventory of water is available to keep thecore covered.During refueling the level in the RCS will normally be maintained above the Reactor Vessel flange.Refueling evolutions that decrease water level below the Reactor Vessel flange are carefullyplanned and procedurally controlled. Loss of forced decaY heat removal at reduced inventory mayresult in more rapid increases in RCS temperatures depending on the time since shutdown.Normal means of core temperature indication and ROS level indication may not be available in therefueling mode. Redundant means of RCS level indication are therefore procedurally installed toassure that the ability to monitor level will not be interrupted. Escalation to Alert would be via EALCA3.1 based on an inventory loss or EAL CA4.1 based on exceeding its temperature duration orpressure criteria.Plant-SpecificSeveral instruments are capable of providing indication of RCS temperature with respect to theTechnical Specification cold shutdown temperature limit (200°F). These include TI-i112C and TI-1220 for forced circulation, CETs for natural circulation and TR-351 for SOC flow.Definitions:UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.February 2016111EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCCNPP Basis Reference(s):I. Technical Specifications Table 1.1-12. OP-7 Shutdown Operations3. OP-I Plant Startup from Cold Shutdown4. NEI 99-01 CU4February 2016112EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:S ubcateg ory:C -Cold Shutdown / Refueling System Malfunction4 -RCS TemperatureInitiating Condition: Unplanned loss of decay heat removal capabilityEAL:CU4.2 Unusual EventLoss of all RCS temperature and RCS level indication for _> 15 min. (Note 4)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable timeMode Applicability:5 -Cold Shutdown, 6 -RefuelBasis:GenericThis EAL is a precursor of more serious conditions and, as a result, is considered to be a potentialdegradation of the level of safety of the plant. In cold shutdown the ability to remove decay heatrelies primarily on forced cooling flow. Operation of the systems that provide this forced coolingmay be jeopardized due to the unlikely loss of electrical power or RCS inventory. Since the RCSusually remains intact in the cold shutdown mode a large inventory of water is available to keep thecore covered.During refueling the level in the RCS will normally be maintained above the Reactor Vessel flange.Refueling evolutions that decrease water level below the Reactor Vessel flange are carefullyplanned and procedurally controlled. Loss of forced decay heat removal at reduced inventory mayresult in more rapid increases in RCS temperatures depending on the time since shutdown.Normal means of core temperature indication and RCS level indication may not be available in therefueling mode. Redundant means of RCS level indication are therefore procedurally installed toassure that the ability to monitor level will not be interrupted. However, if all level and temperatureindication were to be lost in either the cold shutdown of refueling modes, this EAL would result indeclaration of a UE if both temperature and level indication cannot be restored within 15 minutesfrom the loss of both means of indication. Escalation to Alert would be via EAL CA3.1 based on aninventory loss or EAL CA4.1 based on exceeding its temperature criteria.February 2016113EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearPlant-SpecificReactor Vessel water level may be monitored using any of the following instruments:* Refueling Pool Level LE-4140* RCS Level Narrow Range LE-4138* RCS Level Wide Range LE-4139* Local refueling level indicator (LG-4139 and tygon tubing)* Reactor Vessel Level Monitoring System (RVLMS)If RCS water level will be below the bottom of the Pressurizer (48.5 ft el.), IM installs and calibratesthe Refueling Level Cart in the Control Room and places the RCS Wide Range Level MonitoringSystem in service (LE-41 39). The Wide Range Level High/Low alarms and Narrow Range LevelHigh/Low alarms are set above/below the target RCS level. Table I of OP-7, ShutdownOperations, provides a cross-reference of Refueling Pool level and RVLMS alarm lights to variousplant component elevations. If all RCS water level indication is lost during ROS drain down, OP-7requires the following:* Stop the RCS drain down and evaluate the reason for the loss of level indication.*When at least two remote and one local RCS level indicator have been restored and arereading within 0.5 ft of each other, continue RCS drain down. Allow 15 mai. for pressures toequalize. If level readings are not within 0.5 ft, call IM to investigate discrepancies.Several instruments are capable of providing indication of RCS temperature with respect to theTechnical Specification cold shutdown temperature limit (200°F). These include TI-I1I2C and TI-122C for forced circulation, CETs for natural circulation and TR-351 for SDC flow.CCNPP Basis Reference(s):1. Technical Specifications Table 1.1-12. OP-7 Shutdown Operations3. 01-il Post Accident Monitoring System Instrumentation4. OP-i Plant Startup from Cold Shutdown5. NEI 99-01 CU4February 2016 114 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:C -Cold Shutdown / Refueling System Malfunction4 -RCS TemperatureInitiating Condition: Inability to maintain plant in cold shutdownEAL:0A4.1 AlertAn UNPLANNED event results in EITHER:RCS temperature > 200°F for > Table C-4 durationORRCS pressure increase > 10 psi due to an UNPLANNED loss of decay heat removalcapability (this condition is not applicable in solid plant conditions)Table C-4 RCS Reheat Duration ThresholdsCONTAINMENTRCS Status CLSR tts DurationIntact AND not*reduced inventory NA6 mNot intact OR Established 20 min.*reduced inventory Not established 0 mai.* If an RCS heat removal system is in operation within this timeframe and RCS temperature is being reduced, the EAL is notapplicable.Mode Applicability:5 -Cold Shutdown, 6 -RefuelBasis:GenericThe RCS Reheat Duration Thresholds table addresses complete loss of functions required for corecooling for greater than 60 minutes during refuel and cold shutdown modes when RCS integrity isestablished. RCS integrity should be considered to be in place when the RCS pressure boundaryis in its normal condition for the cold~ shutdown mode of operation (e.g., no freeze seals or nozzledams). The status of CONTAINMENT CLOSURE in this condition is immaterial given that the RCSis providing a high pressure barrier to fission product release to the environment. The 60 minutetime frame should allow sufficient time to restore cooling without there being a substantialdegradation in plant safety.The RCS Reheat Duration Thresholds table also addresses the complete loss of functions requiredfor core cooling for greater than 20 minutes during refuel and cold shutdown modes whenFebruary 2016115EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearContainment Closure is established but RCS integrity is not established or RCS inventory isreduced (e.g., mid-loop operation in PWRs)]. [As discussed above, RCS integrity should beassumed to be in place when the RCS pressure boundary is in its normal condition for the coldshutdown mode of operation (e.g., no freeze seals or nozzle dams). The allowed 20 minute timeframe was included to allow operator action to restore the heat removal function, if possible. Theallowed time frame is consistent with the guidance provided by Generic Letter 88-17, "Loss ofDecay Heat Removal" (discussed later in this basis) and is believed to be conservative given that alow pressure Containment barrier to fission product release is established.Finally, complete loss of functions required for core cooling during refuel and cold shutdown modeswhen neither Containment Closure nor RCS integrity are established is addressed. RCS integrity isin place when the RCS pressure boundary is in its normal condition for the cold shutdown mode ofoperation (e.g., no freeze seals or nozzle dams). No delay time is allowed because the evaporatedreactor coolant that may be released into the Containment during this heatup condition could alsobe directly released to the environment.The note (*) indicates that this EAL is not applicable if actions are successful in restoring an RCSheat removal system to operation and RCS temperature is being reduced within the specified timeframe.The 10 psi pressure increase addresses situations where, due to high decay heat loads, the timeprovided to restore temperature control, should be less than 60 minutes. The RCS pressuresetpoint was chosen because it is the lowest pressure that the site can read on installed ControlBoard instrumentation that is equal to or greater than 10 psi.Escalation to Site Area Emergency would be via EAL CS3.1 should boiling result in significant RPVlevel loss leading to core uncovery.A loss of Technical Specification components alone is not intended to constitute an Alert. Thesame is true of a momentary unplanned excursion above the Technical Specification coldshutdown temperature limit when the heat removal function is available.The Emergency Director must remain alert to events or conditions that lead to the conclusion thatexceeding the EAL is imminent. If, in the judgment of the Emergency Director, an imminentsituation is at hand, the classification should be made as if the threshold has been exceeded.Plant-SpecificSeveral instruments are capable of providing indication of RCS temperature with respect to theTechnical Specification cold shutdown temperature limit (200°F). These include TI-i112C and TI-122C for forced circulation, CETs for natural circulation and TR-351 for SDC flow.Containment Closure is the action or condition that ensures Containment and its associatedsystems, structures or components, as listed in STP O-55A, provide a functional barrier to fissionproduct release. Containment closure is initiated by the Shift Manager if plant conditions changethat could raise the risk of a fission product release as a result of a loss of decay heat removal.February 2016 116 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearContainment closure requires, upon a loss of decay heat removal, any open penetration must beclosed or capable of being closed prior to RCS boiling."Reduced inventory" is the condition when the reactor vessel contains irradiated fuel assembliesand RCS water level is at or below 41 ft el.The pressure rise of greater than 10 psi infers an RCS temperature in excess of the TechnicalSpecification cold shutdown limit (200°F) for which this EAL would otherwise permit up to sixtyminutes to restore RCS cooling before declaration of an Alert (RCS intact). This EAL thereforecovers situations in which it is determined that, due to high decay heat loads, the time provided toreestablish temperature control should be less than sixty minutes (as indicated by significant RCSre-pressurization).Pressure indicators PI-103, P1-i103-1 and P1-105 are capable of measuring pressure changes of 10psi. Escalation to a Site Area Emergency would be under EAL CS3.1 should boiling result insignificant Reactor Vessel level loss leading to core uncovery.Definitions:Containment ClosureThe site specific procedurally defined actions taken to secure Containment and its associatedstructures, systems, and components as a functional barrier to fission product release underexisting plant conditions. As applied to CCNPP, Containment Closure is the action or conditionthat ensures Containment and its associated systems, structures or components (SSC), aslisted in STP O-55A, provide a functional barrier to fission product release.UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.CCNPP Basis Reference(s):1. Technical Specifications Table 1.1-12. NO-i-i114 Containment Closure3. STP O-55A-1 (2) Containment Closure Verification4. OP-7 Shutdown Operations5. OP-I Plant Startup from Cold Shutdown6. NEI 99-01 CA4February 2016 117 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:C -Cold Shutdown I Refueling System MalfunctionSubcategory: 5 -CommunicationsInitiating Condition: Loss of all onsite or offsite communications capabilitiesEAL:CU5.1 Unusual EventLoss of all Table C-5 onsite (internal) communication methods affecting the ability toperform routine operationsORLoss of all Table C-5 offsite (external) communication methods affecting the ability toperform offsite notifications to any agencyTable C-5 Communications SystemsOnsite OffsiteSystem (internal) (external)Commercial phone system X XPlant page system XFTS 2001 telephone system XCCNPP Radio System XSatellite Phone System XCellular Phone System X XMode Applicability:5 -Cold Shutdown, 6 -Refuel, D -DefueledBasis:GenericThe purpose of this EAL is to recognize a loss of communications capability that either defeats theplant operations staff ability to perform routine tasks necessary for plant operations or the ability tocommunicate issues with any off-site authorities. The loss of off-site communications ability isexpected to be significantly more comprehensive than the condition addressed by 10 CFR 50.72.The availability of one method of ordinary off-site communications is sufficient to inform federal,state, and local authorities of plant issues. This EAL is intended to be used only whenFebruary 2016118EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearextraordinary means (e.g., relaying of information from radio transmissions, individuals being sentto off-site locations, etc.) are being utilized to make communications possible.PIa nt-SpecificOnsite/offsite communications systems are listed in Table 0-2 (ref. 1, 2, 3).This EAL is the cold condition equivalent of the hot condition EAL SU6.1.CCNPP Basis Reference(s):1. UFSAR Section 7.82. Emergency Response Facility Directory & Communications Equipment Information3. NO-i1-113, Control of Radio Transmitter (PRT)4. NEI 99-01 CU6February 2016119EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: C -Cold Shutdown / Refueling System MalfunctionSubcategory: 6 -Inadvertent CriticalityInitiating Condition: Inadvertent criticalityEAL:0U6.1 Unusual EventAn UNPLANNED sustained positive startup rate observed on nuclear instrumentationMode Applicability:5 -Cold Shutdown, 6 -RefuelBasis:GenericThis EAL addresses criticality events that occur in Cold Shutdown or Refueling modes such as fuelmis-loading events and inadvertent dilution events. This EAL indicates a potential degradation ofthe level of safety of the plant, warranting aUE classification.Escalation would be by Emergency Director judgment.Plant-SpecificThe term "sustained" is used to allow exclusion of expected short-term positive startup rates fromplanned fuel bundle or control rod movements during core alteration. These short-term positivestartup rates are the result of the rise in neutron population due to subcritical multiplication.Definitions:UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.CCNPP Basis Reference(s):1. UFSAR Section 7.5.2.2.2. Technical Specifications 3.9.23. 1005-ALM Reactivity Control Alarm Manual, Window D-05, D-154. AOP-1A Inadvertent Boron Dilution5. NEI 99-01 CU8February 2016 120 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory H -. Hazards and Other Conditions Affecting Plant SafetyEAL Group: ANY (EALs in this category are applicable to anyplant condition, hot or cold.)Hazards are non-plant, system-related events that can directly or indirectly affect plant operation,reactor plant safety or personnel safety.The events of this category pertain to the following subcategories:1. Natural or Destructive PhenomenaNatural events include hurricanes, earthquakes or tornados that have potential to cause plantstructure or equipment damage of sufficient magnitude to threaten personnel or plant safety.Non-naturally occurring events that can cause damage to plant facilities and include aircraftcrashes, missile impacts, etc.2. Fire or ExplosionFires can pose significant hazards to personnel and reactor safety. Appropriate forclassification are fires within the site Protected Area or which may affect operability ofequipment needed for safe shutdown3. Hazardous GasNon-naturally occurring events that can cause damage to plant facilities and include toxic,asphyxiant, corrosive or flammable gas leaks.4. SecurityUnauthorized entry attempts into the Protected Area, bomb threats, sabotage attempts, andactual security compromises threatening loss of physical control of the plant.5. Control Room EvacuationEvents that are indicative of loss of Control Room habitability. If the Control Room must beevacuated, additional support for monitoring and controlling plant functions is necessarythrough the emergency response facilities.February 2016 121 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclear6. JudgmentThe EALs defined in other categories specify the predetermined symptoms or events that areindicative of emergency or potential emergency conditions and thus warrant classification.While these EALs have been developed to address the full spectrum of possible emergencyconditions which may warrant classification and subsequent implementation of the EmergencyPlan, a provision for classification of emergencies based on operator/management experienceand judgment is still necessary. The EALs of this category provide the Emergency Director thelatitude to classify emergency conditions consistent with the established classification criteriabased upon Emergency Director judgment.February 2016122EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 1 -Natural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting the Protected AreaEAL:HUI.1 Unusual EventSeismic event identified by ANY two of the following:* Seismic Monitor indicates a seismic event detected* Earthquake felt in plant* National Earthquake Information Center (Note 7)Note 7: The NEIC can be contacted by calling (303) 273-8500. Select option #1 and inform the analyst you wish toconfirm recent seismic activity in the vicinity of Calvert Cliffs Nuclear Power Plant. Provide the analyst with thefollowing CCNPP coordinates: 380 25' 39.7" north latitude, 760 26' 45" west longitude.Mode Applicability:AllBasis:GenericThis EAL is categorized on the basis of the occurrence of an event of sufficient magnitude to be ofconcern to plant operators.Damage may be caused to some portions of the site, but should not affect ability of safetyfunctions to operate.As defined in the EPRI-sponsored Guidelines for Nuclear Plant Response to an Earthquake, datedOctober 1989, a "felt earthquake" is: An earthquake of sufficient intensity such that: (a) thevibratory ground motion is felt at the nuclear plant site and recognized as an earthquake based ona consensus of Control Room operators on duty at the time, and (b) for plants with operableseismic instrumentation, the seismic switches of the plant are activated.The National Earthquake Center can confirm if an earthquake has occurred in the area of the plant.Plant-SpecificCCNPP seismic instrumentation actuates at 0.01g upon sensing any ground motion. Damage tosome portions of the site may occur as a result of the felt earthquake but it should not affect theability of safety functions to operate. This event escalates to an Alert under EAL HA1 .1 if theearthquake exceeds the Operating Basis Earthquake (OBE) magnitude of 0.08 g horizontal or0.053g vertical. (ref. 1)February 2016 123 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearThe National Earthquake Information Center (NEIC) can confirm seismic activity in the vicinity ofthe CCNPP. The NEIC can be contacted by calling (3013) 273-8500. Select option #1 and informthe analyst you wish to confirm recent seismic activity in the vicinity of Calvert Cliffs Nuclear PowerPlant. Provide the analyst with the following CCNPP coordinates: 330 25' 39.7" north latitude, 76026' 45" west longitude (ref. 3). Alternatively, information regarding the extent of a near-siteearthquake can be obtained by calling the University of Delaware (302) 821-1576.CCNPP Basis Reference(s):1. 0I-46 Seismic Measurement Equipment2. UFSAR Section 7.5.7 Seismic Instrumentation3. Calvert Cliffs ISFSI USAR Section 2.1.1 Site Location4. STPI M-260-0 Seismic Instrumentation Channel Check5. NE! 99-01 HU16. ECP-1 3-000653, Replace the existing five channel SMA-3 Seismic Montitor with a KinemetricsCondor Seismic Monitoring SystemFebruary 2016124EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 1 -Natural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting the Protected AreaEAL:HUI.2 Unusual EventTornado striking within PROTECTED AREA BOUNDARYORSustained high winds > 45 rn/sec (100 mph)Mode Applicability:AllBasis:GenericThis EAL is categorized on the basis of the occurrence of an event of sufficient magnitude to be ofconcern to plant operators.This EAL is based on a tornado striking (touching down) or high winds within the Protected Area.Escalation of this emergency classification level, if appropriate, would be based on visible damage,or by other in plant conditions, via EAL HA1 .2.Plant-SpecificAll Class 1 safe shutdown structures are designed for a wind velocity of 100 mph, 30 feet aboveground using a gust factor of 1.1. The meteorological tower 15-minute average wind speedreadings are the "sustained" wind speeds used to assess this EAL.Definitions:Protected AreaThe site specific area which normally encompasses all controlled areas within the securityProtected Area fence.CCNPP Basis Reference(s):1. ES-005 Civil and Structural Design Criteria2. CCIPEEE RAN 97-031 High Winds, Floods and Other External Events Analysis3. NEI 99-01 HU1February 2016 125 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 1 -Natural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting the Protected AreaEAL:HU1.3 .Unusual EventInternal flooding that has the potential to affect ANY SAFETY-RELATED STRUCTURE,SYSTEM, OR COMPONENT required by Technical Specifications for the current operatingmode in ANY Table H-I areaTable H-I Safe Shutdown Areas* Control Room* Containment* Auxiliary Building* Diesel Generator Rooms* Intake Structure* 1A/0C DG Buildings* RWT* RVVT Rooms* CST No. 12* FOSTNo. 21* Auxiliary Feed Pump RoomsMode Applicability:AllBasis:GenericThis EAL is categorized on the basis of the occurrence of an event of sufficient magnitude to be ofconcern to plant operators.This EAL addresses the effect of internal flooding caused by events such as component failures,equipment misalignment, or outage activity mishaps.Escalation of this emergency classification level, if appropriate, would be based visible damage viaEAL HAl1.3, or by other plant conditions.February 2016126EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearPlant-SpecificThis threshold addresses the affect of flooding caused by internal events such as componentfailures, Circulating, Saltwater, Component Cooling or Service Water line ruptures, equipmentmisalignment, fire suppression system actuation, and outage activity mishaps. The internal floodingareas contain systems that are:* Required for safe shutdown of the plant* Not designed to be wetted or submerged* Susceptible to internal flooding eventsFlooding as used in this EAL describes a condition where water is entering the room faster thaninstalled equipment is capable of removal, resulting in a rise of water level within the room.Classification of this EAL should not be delayed while corrective actions are being taken to isolatethe water source.Table H-i Safe Shutdown Areas include all SAFETY-RELATED STRUCTURE, SYSTEM, ORCOMPONENT needed for safe shutdown.Safety-Related Structures, Systems and Components (as defined in 1OCFR5O.2)Those structures, systems and components that are relied upon to remain functional duringand following design basis events to assure:(1) The integrity of the reactor coolant pressure boundary;(2) The capability to shut down the reactor and maintain it in a safe shutdown condition;(3) The capability to prevent or mitigate the consequences of accidents which could resultin potential offsite exposures.CCNPP Basis Reference(s):1. CCPRA RAN: 96-O24FLOOD Flood Rule Development2. CCPRA RAN: 98-062, Internal Flood Initiating Event Frequencies3. CCPRA RAN: 98-065, Flood Evaluations (Flood Queries)4. ICIO-ALM ESFAS 13 Alarm Manual, J-17, CC PP RM LVL HI5. 1C10-ALM ESFAS 13 Alarm Manual, J-18, SRW PP RM LVL HI6. 1C10-ALM ESFAS 13 Alarm Manual, J-22, CNDSR PIT LVL HI7. 1C10-ALM ESFAS 13 Alarm Manual, J-23, INTAKE SUMP STRUCTURE LVL HI8. 1C10-ALM ESFAS 13 Alarm Manual, J-24, INTAKE STRUCTURE CH TRIP9. Drawing 61502 Plant Property and Buildings10. UFSAR Section 5A.2 Classes of Structures, Systems, and Equipment11. NEI 99-01 HU1February 2016 127 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 1 -Natural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting the Protected AreaEAL:HUI.4 Unusual EventTurbine failure resulting in casing penetration or damage to turbine or generator sealsMode Applicability:AllBasis:GenericThese EALs are categorized on the basis of the occurrence of an event of sufficient magnitude tobe of concern to plant operators.This EAL addresses main turbine rotating component failures of sufficient magnitude to causeobservable damage to the turbine casing or to the seals of the turbine generator. Generator sealdamage observed after generator purge does not meet the intent of this EAL because it did notimpact normal operation of the plant.Of major concern is the potential for leakage of combustible fluids (lubricating oils) and gases(hydrogen cooling) to the plant environs. Actual FIRES and flammable gas build up areappropriately classified via EAL HU2.1 and EAL HU3.1.This EAL is consistent with the definition of a UE while maintaining the anticipatory nature desiredand recognizing the risk to non-safety related equipment.Escalation of this emergency classification level, if appropriate, would be to EAL HAl1.4 based ondamage done by PROJECTILES generated by the failure or in conjunction with a steam generatortube rupture. These latter events would be classified by the Category R EALs or Category F EALs.Plant-SpecificThe turbine generator stores large amounts of rotational kinetic energy in its rotor. In the unlikelyevent of a major mechanical failure, this energy may be transformed into both rotational andtranslational energy of rotor fragments. These fragments may impact the surrounding stationaryparts. If the energy-absorbing capability of these stationary turbine generator parts is insufficient,external projectiles will be released. These ejected projectiles may impact various plant structures,including those housing safety related equipment.February 2016 128 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearIn the event of projectile ejection, the probability of a strike on a plant region is a function of theenergy and direction of an ejected projectile and of the orientation of the turbine with respect to theplant region.Failure of turbine or generator seals may be indicated by a loss of seal oil pressure or loss ofcondenser vacuum (ref. 2, 3).CCNPP Basis Reference(s):1. AOP-7E Main Turbine Malfunction2. AOP-7G Loss of Condenser Vacuum3. 1 C02-ALM B-I10 Seal Oil Duff Press Lo4. NEI 99-01 HU1February 2016129EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 1 -Natural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting the Protected AreaEAL:HUI.5 Unusual EventBay water level > bottom of the traveling screen cover housing (+ 120 in. Mean Sea Level)ORBay water level < 13.6 ft below intake concrete level (- 43.2 in. Mean Sea Level)Mode Applicability:AllBasis:GenericThis EAL is categorized on the basis of the occurrence of an event of sufficient magnitude to be ofconcern to plant operators.This EAL addresses other site specific phenomena that can also be precursors of more seriousevents.Plant-SpecificThis threshold addresses high and low bay water level conditions that could be a precursor of moreserious events.Since the Intake Structure houses the saltwater pumps that are essential for safe shutdown ofCCNPP, the structure was designed as a Category I structure for seismic, tornado, and hurricaneconditions. The Intake Structure is also designed to protect the saltwater pump motors fromexternal flooding due to the maximum hypothetical hurricane tide and storm surges, including waveaction. The Intake Structure design loads and conditions are shown in UFSAR Table 5-7.l0 ft (+120 in.) Mean Sea Level (approximately bottom of the travelling screen cover) is the stillwater level used for the Intake Structural Analysis. This value was selected to be anticipatory to thedesign level of 18 ft Mean Sea Level (top of the travelling screen cover).The predicted extreme low tide elevation is -3.6 ft (-43.2 in.) Mean Sea Level. However, the planthas been designed for -4.0 ft Mean Sea Level and can continue to operate with an extreme lowFebruary 2016 130 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclearwater Elevation of -6.0 ft Mean Sea Level. The top of the saltwater pump intakes is at -9.5 ft MeanSea Level.Operations can measure water level from the intake concrete walking level to the Bay surface witha tape measure. This level is measured upstream (i.e., before) the trash racks. This EAL criterion ismet if the water is 13.6 ft below the intake concrete level by observation. This measurementrequires judgment because the Bay surface is not normally still.Radar probes (1-LIT-1100 & 2-LIT-2100) have been installed which provide local indication (1-LI-1100 & 2-LI-21 00) of Intake water level in inches relative to Mean Sea Level (ref. 4).CCNPP Basis Reference(s):1. UFSAR Sections 2.8.3.6 and 2.8.3.72. UFSAR Table 5-73. 1C10-ALM ESFAS 14 Alarm Manual, J-234. ECP-10-0002085. NEI 99-01 HU1February 2016131EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:S ubcateg ory:H -Hazards and Other Conditions Affecting Plant SafetyNatural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting Vital AreasEAL:HAl.1 AlertEITHER:Seismic Monitor indicates a seismic event > OBE (0.08 g horizontal or 0.053gvertical)ORControl Room indication of degraded performance of ANY SAFETY-RELATEDSTRUCTURE, SYSTEM, OR COMPONENTANDEarthquake confirmed by EITHER:Earthquake felt in plantORNational Earthquake Information Center (Note 7)Note 7: The NEIC can be contacted by calling (303) 273-8500. Select option #1 and inform the analyst you wish toconfirm recent seismic activity in the vicinity of Calvert Cliffs Nuclear Power Plant. Provide the analyst with thefollowing CCNPP coordinates: 380 25' 39.7" north latitude, 760 26' 45" west longitude.Mode Applicability:AllBasis:GenericThese EALs escalate from HUI.1 in that the occurrence of the event has resulted in damage to thesafety systems in those structures evidenced by Control Room indications of degraded systemresponse or performance. The occurrence of degraded system response is intended todiscriminate against lesser events. The initial report should not be interpreted as mandating alengthy damage assessment prior to classification. No attempt is made in this EAL to assess theactual magnitude of the damage. The significance here is not that a particular system or structurewas damaged, but rather, that the event was of sufficient magnitude to cause this degradation.Escalation of this emergency classification level, if appropriate, would be based on SystemMalfunction EALs.Seismic events of this magnitude can result in a VITAL AREA being subjected to forces beyonddesign limits, and thus damage may be assumed to have occurred to plant safety systems.February 2016132EP-AA-1 011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearThe National Earthquake Information Center can confirm if an earthquake has occurred in the areaof the plant.Plant-SpecificThis EAL is based on the UFSAR design Operating Basis Earthquake (OBE) of 0.08 g horizontal or0.053 g vertical acceleration. Seismic events of this magnitude can cause damage to plant safetyfunctions.The method of determining whether the OBE has been exceeded relies on either the actuation ofor evaluation of data from the CCNPP seismic monitor or indication of actual degraded systemperformance with seismic activity confirmed by shift operators on duty in the Control Roomdetermining that the ground motion was felt or corroborated by the NEIC. According to 01-46,confirmation by one or more Control Room operators with respect to ground motion helps avoidunnecessary classification if the seismic switches inadvertently trip or detect vibrations not relatedto an earthquake.CCNPP seismic instrumentation actuates at 0.01g upon sensing any seismic activity.The National Earthquake Information Center (NEIC) can confirm seismic activity in the vicinity ofthe CCNPP. The NEIC can be contacted by calling (303) 273-8500. Select option #1 and informthe analyst you wish to confirm recent seismic activity in the vicinity of Calvert Cliffs Nuclear PowerPlant. Provide the analyst with the following CCNPP coordinates: 330 25' 39.7" north latitude, 76026' 45" west longitude (ref. 3). Alternatively, information regarding the extent of a near-siteearthquake can be obtained by calling the University of Delaware (302) 821-1576.Definitions:Safety-Related Structures, Systems and Components (as defined in 10CFR50.2)Those structures, systems and components that are relied upon to remain functional duringand following design basis events to assure:(1) The integrity of the reactor coolant pressure boundary;(2) The capability to shut down the reactor and maintain it in a safe shutdown condition;(3) The capability to prevent or mitigate the consequences of accidents which could resultin potential offsite exposures.February 2016 133 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCCNPP Basis Reference(s):1. 0I-46 Seismic Measurement Equipment2. UFSAR Section 7.5.7 Seismic Instrumentation3. Calvert Cliffs ISFSI USAR Section 2.1.1 Site Location4. STPI M-260-0 Seismic Instrumentation Channel Check5. NEI 99-01 HA16. ECP-1 3-000653, Replace the existing five channel SMA-3 Seismic Montitor with a KinemetricsCondor Seismic Monitoring SystemFebruary 2016134EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryAnnexFxAlnn NunlnarW Vl I vml ........ m I I ....Category:Subcategory:H -Hazards and Other Conditions Affecting Plant SafetyI -Natural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting Vital AreasEAL:HA1.2 AlertTornado striking or sustained high winds > 45 rn/sec (100 mph) resulting in EITHER:VISIBLE DAMAGE to ANY SAFETY-RELATED STRUCTURE, SYSTEM, ORCOMPONENT within ANY Table H-I areaORControl Room indication of degraded performance of ANY SAFETY-RELATEDSTRUCTURE, SYSTEM, OR COMPONENT within ANY Table H-I areaTable H-I Safe Shutdown Areas* Control Room* Containment* Auxiliary Building* Diesel Generator Rooms* Intake Structure* IA/0C DG Buildings* RWT* RWT Rooms* CST No. 12* FOSTNo. 21* Auxiliary Feed Pump RoomsMode Applicability:AllBasis:GenericThis EAL escalates from HU1.2 in that the occurrence of the event has resulted in visible damageto plant structures or areas containing equipment necessary for a safe shutdown, or has causeddamage to the safety systems in those structures evidenced by Control Room indications ofdegraded system response or performance. The occurrence of visible damage and/or degradedsystem response is intended to discriminate against lesser events. The initial report should not beinterpreted as mandating a lengthy damage assessment prior to classification. No attempt is madeFebruary 2016135EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearin this EAL to assess the actual magnitude of the damage. The significance here is not that aparticular system or structure was damaged, but rather, that the event was of sufficient magnitudeto cause this degradation.Escalation of this emergency classification level, if appropriate, would be based on SystemMalfunction EALs.This EAL is based on a tornado striking (touching down) or high winds that have caused visibledamage to structures containing functions or systems required for safe shutdown of the plant.Plant-SpecificThis threshold addresses events that may have resulted in a Safe Shutdown Area being subjectedto forces beyond design limits and thus damage may be assumed to have occurred to plant safetysystems. Safe Shutdown Areas are vital areas that house equipment the operation of which maybe needed to ensure the reactor safely reaches and is maintained in cold shutdown. SafeShutdown Areas include structures that contain the equipment of concern. The Alert classificationis appropriate if relevant plant parameters indicate that the performance of safety systems in theaffected Safe Shutdown Areas has been degraded. No attempt should be made to fully inventorythe actual magnitude of the damage or quantify the degradation of safety system performance priorto declaration of an Alert under this threshold.This EAL is based on the structural design basis of 100 mph. Wind loads of this magnitude cancause damage to safety functions. The meteorological tower 15-minute average wind speedreadings are the "sustained" wind speeds used to assess this EAL.Table H-I Safe Shutdown Areas include all SAFETY-RELATED STRUCTURE, SYSTEM, ORCOMPONENT needed for safe shutdown.Definitions:Safety-Related Structures, Systems and Components (as defined in 10CFR50.2)Those structures, systems and components that are relied upon to remain functional duringand following design basis events to assure:(1) The integrity of the reactor coolant pressure boundary;(2) The capability to shut down the reactor and maintain it in a safe shutdown condition;(3) The capability to prevent or mitigate the consequences of accidents which could resultin potential offsite exposures.February 2016 136 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearVisible DamageDamage to equipment or structure that is readily observable without measurements, testing, oranalysis. Damage is sufficient to cause concern regarding the continued operability or reliabilityof affected safety structure, system, or component. Example damage includes: deformationdue to heat or impact, denting, penetration, rupture, cracking, paint blistering. Surfaceblemishes (e.g., paint chipping, scratches) should not be included.CCNPP Basis Reference(s):1. ES-005 Civil and Structural Design Criteria2. CCIPEEE RAN 97-031 High Winds, Floods and Other External Events Analysis Section 5.3.13. Drawing 61502 Plant Property and Buildings4. UFSAR Section 5A.2 Classes of Structures, Systems, and Equipment5. NEI 99-01 HAlFebruary 2016137EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 1 -Natural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting Vital AreasEAL:HA1.3 AlertInternal flooding in ANY Table H-i area resulting in EITHER:An electrical shock hazard that precludes access to operate or monitor ANY SAFETY-RELATED STRUCTURE, SYSTEM, OR COMPONENT within ANY Table H-i areaORControl Room indication of degraded performance of ANY SAFETY-RELATEDSTRucTuRE, SYSTEM, OR COMPONENT within ANY Table H-i areaTable H-I Safe Shutdown Areas,, Control Room* Containment* Auxiliary Building*, Diesel Generator Rooms* Intake Structure* 1A/0C DG Buildings* RWT* RWT Rooms* CST No. 12* FOST No. 21* Auxiliary Feed Pump RoomsMode Applicability:AllBasis:GenericEscalation of this emergency classification level, if appropriate, would be based on SystemMalfunction EALs.This EAL addresses the effect of internal flooding caused by events such as component failures,equipment misalignment, or outage activity mishaps. It is based on the degraded performance ofsystems, or has created industrial safety hazards (e.g., electrical shock) that preclude necessaryFebruary 2016 138 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearaccess to operate or monitor safety equipment. The inability to access, operate or monitor safetyequipment represents an actual or substantial potential degradation of the level of safety of theplant.Flooding as used in this EAL describes a condition where water is entering the room faster thaninstalled equipment is capable of removal, resulting in a rise of water level within the room.Classification of this EAL should not be delayed while corrective actions are being taken to isolatethe water source.PlIant-SprecificThis threshold addresses the effect of flooding caused by internal events such as componentfailures such as Circulating, Saltwater, Component Cooling or Service Water line ruptures,equipment misalignment, fire suppression system actuation, steam leaks or outage activitymishaps. The Internal Flooding Areas contain systems that are:* Required for safe shutdown of the plant* Not designed to be wetted or submerged* Susceptible to internal flooding eventsUncontrolled internal flooding that has degraded safety-related equipment or created a safetyhazard precluding access necessary for the safe operation or monitoring of safety equipmentwarrants declaration of an Alert.Definitions:Safety-Related Structures, Systems and Components (as defined in 100FR50.2)Those structures, systems and components that are relied upon to remain functional duringand following design basis events to assure:(1) The integrity of the reactor coolant pressure boundary;(2) The capability to shut down the reactor and maintain it in a safe shutdown condition;(3) The capability to prevent or mitigate the consequences of accidents which could resultin potential offsite exposures.February 2016 139 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCCNPP Basis Reference(s):1. CCPRA RAN: 96-024FLOOD Flood Rule Development2. CCPRA RAN: 98-062, Internal Flood Initiating Event Frequencies3. CCPRA RAN: 98-065, Flood Evaluations (Flood Queries)4. 1C10-ALM ESFAS 13 Alarm Manual, J-17, CC PP RM LVL HI5. 1C10-ALM ESFAS 13 Alarm Manual, J-18, SRW PP RM LVL HI6. 1CI0-ALM ESFAS 13 Alarm Manual, J-22, CNDSR PIT LVL HI7. 1C10-ALM ESFAS 13 Alarm Manual, J-23, INTAKE SUMP STRUCTURE LVL HI8. 1C1O-ALM ESFAS 13 Alarm Manual, J-24, INTAKE STRUCTURE OH TRIP9. NEI 99-01 HA1February 2016140EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:S ubcateg ory:H -Hazards and Other Conditions Affecting Plant SafetyI -Natural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting Vital AreasEAL:HA1.4 AlertTurbine failure-generated PROJECTILES resulting in EITHER:VISIBLE DAMAGE to or penetration of ANY SAFETY-RELATED STRUCTURE,SYSTEM, OR COMPONENT within ANY Table H-I areaORControl Room indication of degraded performance of ANY SAFETY-RELATEDSTRUCTURE, SYSTEM, OR COMPONENT within ANY Table H-i areaTable H-I Safe Shutdown Areas* Control Room* Containment* Auxiliary Building* Diesel Generator Rooms* Intake Structure* lA/0C DO Buildings* RWT* RWT Rooms* CST No. 12* FOSTNo. 21* Auxiliary Feed Pump RoomsMode Applicability:AllBasis:GenericThis EAL escalates from HU1 .4 in that the occurrence of the event has resulted in visible damageto plant structures or areas Containing equipment necessary for a safe shutdown, or has causeddamage to the safety systems in those structures evidenced by Control Room indications ofdegraded system response or performance. The occurrence of visible damage and/or degradedsystem response is intended to discriminate against lesser events. The initial report should not beFebruary 2016141EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearinterpreted as mandating a lengthy damage assessment prior to classification. No attempt is madein this EAL to assess the actual magnitude of the damage. The significance here is not that aparticular system or structure was damaged, but rather, that the event was of sufficient magnitudeto cause this degradation.Escalation of this emergency classification level, if appropriate, would be based on SystemMalfunction EALs.This EAL addresses the threat to safety related equipment imposed by projectiles generated bymain turbine rotating component failures. Therefore, this EAL is consistent with the definition of anAlert in that the potential exists for actual or substantial potential degradation of the level of safetyof the plant.Plant-SpecificThe turbine generator stores large amounts of rotational kinetic energy in its rotor. In the unlikelyevent of a major mechanical failure, this energy may be transformed into both rotational andtranslational energy of rotor fragments. These fragments may impact the surrounding stationaryparts. If the energy-absorbing capability of these stationary turbine generator parts is insufficient,external projectiles will be released. These ejected projectiles may impact various plant structures,including those housing safety related equipment.Table H-i Safe Shutdown Areas include all SAFETY-RELATED STRUCTURE, SYSTEM, ORCOMPONENT needed for safe shutdown.Definitions:ProjectileAn object directed toward a NPP that could cause concern for its continued operability,reliability, or personnel safety.Safety-Related Structures, Systems and Components (as defined in 10CFR50.2)Those structures, systems and components that are relied upon to remain functional duringand following design basis events to assure:(1) The integrity of the reactor coolant pressure boundary;(2) The capability to shut down the reactor and maintain it in a safe shutdown condition;(3) The capability to prevent or mitigate the consequences of accidents which could resultin potential offsite exposures.February 2016 142 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearVisible DamageDamage to equipment or structure that is readily observable without measurements, testing, oranalysis. Damage is sufficient to cause concern regarding the continued operability or reliabilityof affected safety structure, system, or component. Example damage includes: deformationdue to heat or impact, denting, penetration, rupture, cracking, paint blistering. Surfaceblemishes (e.g., paint chipping, scratches) should not be included.CCNPP Basis Reference(s):1. Drawing 61502 Plant Property and Buildings2. UFSAR Section 5A.2 Classes of Structures, Systems, and Equipment3. CCIPEEE RAN 97-031 High Winds, Floods and Other External Events Analysis Section 5.3.14. NEI 99-01 HA1February 2016143EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 1 -Natural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting Vital AreasEAL:HA1.5 AlertBay water level > top of the traveling screen cover housingORBay water level or inside travelling screen water level < 16.0 ft below intake concrete level(-72.0 in. Mean Sea Level)Mode Applicability:AllBasis:GenericThis EAL addresses other site specific phenomena that result in visible damage to vital areas orresults in indication of damage to safety structures, systems, or components containing functionsand systems required for safe shutdown of the plant that can also be precursors of more seriousevents.Plant-SpecificThis threshold covers high and low water level conditions that may have resulted in a plant VitalArea being subjected to levels beyond design limits, and thus damage may be assumed to haveoccurred to plant safety systems.Since the Intake Structure houses the saltwater pumps that are essential for safe shutdown ofCCNPP, the structure was designed as a Category I structure for seismic, tornado, and hurricaneconditions. The Intake Structure is also designed to protect the saltwater pump motors fromexternal flooding due to the maximum hypothetical hurricane tide and storm surges, including waveaction. The Intake Structure design loads and conditions are shown in UFSAR Table 5-7.18 ft Mean Sea Level (+216 in., top of the travelling screen cover) is the design flood level.The predicted extreme low tide elevation is -3.6 ft Mean Sea Level. However, the plant has beendesigned for -4.0 ft Mean Sea Level and can continue to operate with an extreme low waterElevation of-6.0 ft (-72.0 in.) Mean Sea Level. This EAL criterion is met if the water is 16 ft belowthe intake concrete level by observation. This measurement requires judgment because the BayFebruary 2016 144 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclearsurface is not normally still. Bay water level is upstream (i.e., before) the travelling screens. Insidetravelling screen water level is considered at the Alert classification because differential pressureacross the screens may depress the level below the bay water level and reduce NPSH available tothe saltwater pumps. The top of the saltwater pump intake is at -9.5 ft Mean Sea Level.Radar probes (1-LIT-I1100 & 2-LIT-2100) have been installed which provide local indication (1-LI-1100 & 2-LI-21 00) of Intake water level in inches relative to Mean Sea Level (ref. 4).CCNPP Basis Reference(s):1. UFSAR Sections 2.8.3.6 and 2.8.3.72. UFSAR Table 5-73. 1C10-ALM ESFAS 14 Alarm Manual, J-234. ECP-10-0002085. NEI 99-01 HA1February 2016145EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryFvI:=nn M,,rlaarvuuwvn b vuEnnv

• ilMVlVV41Category:Subcategory:H -Hazards and Other Conditions Affecting Plant SafetyI -Natural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting Vital AreasEAL:HA1.6 ,AlertVehicle crash resulting in EITHER:VISIBLE DAMAGE to ANY SAFETY-RELATED STRUCTURE, SYSTEM, ORCOMPONENT within ANY Table H-I areaORControl Room indication of degraded performance of ANY SAFETY-RELATEDSTRUCTURE, SYSTEM, OR COMPONENT within ANY Table H-I areaLTable H-I Safe Shutdown Areas* Control Room* Containment* Auxiliary Building* Diesel Generator Rooms* Intake Structure* 1A/0C DG Buildings* RWT* RWT Rooms* CST No. 12* FOSTNo. 21* Auxiliary Feed Pump RoomsMode Applicability:AllBasis:GenericThe occurrence of visible damage and/or degraded system response is intended to discriminateagainst lesser events. The initial report should not be interpreted as mandating a lengthy damageassessment prior to classification. No attempt is made in this EAL to assess the actual magnitudeof the damage. The significance here is not that a particular system or structure was damaged, butrather, that the event was of sufficient magnitude to cause this degradation.February 2016146EP-AA-1011 Addendum 3(Revision I)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearEscalation of this emergency classification level, if appropriate, would be based on SystemMalfunction EALs.This EAL addresses vehicle crashes within the Protected Area that results in visible damage tovital areas or indication of damage to safety structures, systems, or components containingfunctions and systems required for safe shutdown of the plant.Plant-SpecificThis EAL is intended to address crashes of vehicle types large enough to cause significantdamage to plant structures containing functions and systems required for safe shutdown of theplant. Vehicle types include automobiles, aircraft, trucks, cranes, forklifts, waterborne craft, etc.Table H-I Safe Shutdown Areas include all SAFETY-RELATED STRUCTURE, SYSTEM, ORCOMPONENT needed for safe shutdown.Definitions:Safety-Related Structures, Systems and Components (as defined in 10CFR50.2)Those structures, systems and components that are relied upon to remain functional duringand following design basis events to assure:(I) The integrity of the reactor coolant pressure boundary;(2) The capability to shut down the reactor and maintain it in a safe shutdown condition;(3) The capability to prevent or mitigate the consequences of accidents which could resultin potential offsite exposures.Visible DamageDamage to equipment or structure that is readily observable without measurements, testing, oranalysis. Damage is sufficient to cause concern regarding the continued operability or reliabilityof affected safety structure, system, or component. Example damage includes: deformationdue to heat or impact, denting, penetration, rupture, cracking, paint blistering. Surfaceblemishes (e.g., paint chipping, scratches) should not be included.CCNPP Basis Reference(s):I. Drawing 61502 Plant Property and Buildings2. UFSAR Section 5A.2 Classes of Structures, Systems, and Equipment3. NEI 99-01 HA1February 2016 147 EP-AA-1011 Addendum 3(Revision I)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexIFxelnn Nuc~learCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 2 -Fire or ExplosionInitiating Condition: Fire within the Protected Area not extinguished within 15 min. ofdetection or explosion within the Protected AreaEAL:HU2.1 Unusual EventFIRE not extinguished within 15 min. of Control Room notification or verification of aControl Room fire alarm in the North Service Building, Turbine Building, Butler Building(Note 9) or ANY Table H-I area (Note 4)* Butler Building is only considered adjacent in Modes 5, 6 or D.Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time.Note 9: Butler Building is only considered adjacent in Modes 5, 6 and D.Table H-I Safe Shutdown Areas* Control Room* Containment* Auxiliary Building* Diesel Generator Rooms* Intake Structure* 1A/0C DG Buildings* RWT* RWT Rooms* CST No. 12* FOST No. 21* Auxiliary Feed Pump Rooms* Service Water Rooms* Switchgear RoomsMode Applicability:AllFebruary 2016148EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBasis:GenericThis EAL addresses the magnitude and extent of fires that may be potentially significant precursorsof damage to safety systems. It addresses the FIRE, and not the degradation in performance ofaffected systems that may result.As used here, detection is visual observation and report by plant personnel or sensor alarmindication.The purpose of this threshold is to address the magnitude and extent of fires that may bepotentially significant precursors to damage to safety systems. As used here, notification is visualobservation and report by plant personnel or sensor alarm indication. The 15-minute period toextinguish the fire begins with a credible notification that a fire is occurring or indication of a validfire detection system alarm. Determination of a valid fire detection system alarm includes actionsthat can be taken within the Control Room or at nearby Fire Panels to determine that the alarm isnot spurious. These actions include the use of direct or indirect indications such as redundantalarms or instrumentation readings associated with the area to ensure the alarm is not spuriousand is an indication of a fire. An alarm verified in this manner is assumed to be an indication of afire unless personnel dispatched to the scene disprove the alarm within the 15-minute period. Thereport, however, shall not be required to verify the alarm.The intent of this 15 minute duration is to size the fire and to discriminate against small fires thatare readily extinguished (e.g., smoldering waste paper basket).Plant-SpjecificTable H-I Safe Shutdown Areas include all SAFETY-RELATED STRUCTURE, SYSTEM, ORCOMPONENT needed for safe shutdown. The North Service Building, Turbine Building andButler Building (only when in Modes 5, 6 or D) are adjacent structures.Definitions:FireCombustion characterized by heat and light. Sources of smoke such as slipping drive belts oroverheated electrical equipment do not constitute fires. Observation of flame is preferred but isnot required if large quantities of smoke and heat are observed.CCNPP Basis Reference(s):1. Drawing 61502 Plant Property and Buildings2. UFSAR Section 5A.2 Classes of Structures, Systems, and Equipment3. AOP-9 Series Fire Procedures4. NEI 99-01 HU2February 2016 149 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 2 -Fire or ExplosionInitiating Condition: Fire within the Protected Area not extinguished within 15 mai. ofdetection or explosion within the Protected AreaEAL:HU2.2 Unusual EventEXPLOSION within the PROTECTED AREAMode Applicability:AllBasis:GenericThis EAL addresses the magnitude and extent of explosions that may be potentially significantprecursors of damage to safety systems. It addresses the explosion, and not the degradation inperformance of affected systems that may result.This EAL addresses only those explosions of sufficient force to damage permanent structures orequipment within the Protected Area.No attempt is made to assess the actual magnitude of the damage. The occurrence of theexplosion is sufficient for declaration.The Emergency director also needs to consider any security aspects of the explosion, if applicable.Escalation of this emergency classification level, if appropriate, would be based on EAL HA2.1.Plant-SpecificWhile some explosions may also result in fires that exceed EAL HU2.1, no fire is necessary todeclare an emergency in the event of an explosion. If a fire also occurs as a result or with anexplosion, declare the Unusual Event based on the explosion and monitor the progress of the firefor potential escalation due to fire damage.When used in the context of an explosion, "catastrophic failure" of a component (e.g., tank, heatexchanger, etc.) signifies a rupture of sufficient magnitude that adjacent or nearby components areaffected.February 2016 150 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearOperatin~q exp:erience6/25/09 Davis-Besse -A transitory Alert condition was determined to have existed based on'Onsite Explosion Affecting Plant Operation'. A catastrophic failure-explosion of the ConstantCurrent Potential Device (CCPD) on 'J' Bus near Air Circuit Breaker (ACB) 34563 resulted in a lossof switchyard 345 KV Bus 'J'. This event de-energized Startup Transformer 01 which is a tie fromoffsite sources to the Unit 13.8 KV Busses. The licensee stated that initially, the severity of theCCPD failure was not recognized because of the night time conditions and minimal lighting in thearea. After daylight examination of the location of the event, it was determined that the failure ofthe CCPD should have been classified as an explosion affecting plant operation. Consequently,the licensee made the after-the-fact declaration.10/27/08 Quad Cities -Quad Cities Station declared an Unusual Event due to an explosion in theprotected area. The radwaste floor drain surge tank building had physical damage after reports ofan explosion in the area. The damage was to the block structure of the radwaste floor drain surgetank building but the radwaste tank itself was not impacted. The cause of the explosion was stillunknown but appeared to be related to a buildup of some kind of hydrocarbon gas.Definitions:Explosion.A rapid, violent, unconfined combustion, or catastrophic failure of pressurized/energizedequipment that imparts energy of sufficient force to potentially damage permanent structures,systems, or components.Protected AreaThe site specific area which normally encompasses all controlled areas within the securityProtected Area fence.CCNPP Basis Reference(s):1. Drawing 61502 Plant Property and Buildings2. NEI 99-01 HU2February 2016 151 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:H -Hazards and Other Conditions Affecting Plant Safety2 -Fire or ExplosionInitiating Condition: Fire or explosion affecting the operability of plant safety systemsrequired to establish or maintain safe shutdownEAL:HA2.1 AlertFIRE or EXPLOSION resulting in EITHER:VISIBLE DAMAGE to ANY SAFETY-RELATED STRUCTURE, SYSTEM, ORCOMPONENT within ANY Table H-I areaORControl Room indication of degraded performance of ANY SAFETY-RELATEDSTRUCTURE, SYSTEM, OR COMPONENT within ANY Table H-I areaTable H-I Safe Shutdown Areas* Control Room* Containment* Auxiliary Building* Diesel Generator Rooms* Intake Structure* 1A/0C DG Buildings* RWT* RWT Rooms* CST No. 12* FOSTNo. 21* Auxiliary Feed Pump RoomsMode Applicability:AllBasis:GenericVisible damage is used to identify the magnitude of the fire or explosion and to discriminate againstminor fires and explosions.The reference to structures containing safety systems or components is included to discriminateagainst fires or explosions in areas having a low probability of affecting safe operation. TheFebruary 2016152EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearsignificance here is not that a safety system was degraded but the fact that the fire or explosionwas large enough to cause damage to these systems.The use of visible damage should not be interpreted as mandating a lengthy damage assessmentprior to classification. The declaration of an Alert and the activation of the Technical SupportCenter will provide the Emergency Director with the resources needed to perform detailed damageassessments.The Emergency Director also needs to consider any security aspects of the explosion.Escalation of this emergency classification level, if appropriate, will be based on EALs in Category5, Category F or Category R.Plant-SpecificTable H-I Safe Shutdown Areas include all SAFETY-RELATED STRUCTURE, SYSTEM, ORCOMPONENT needed for safe shutdown.Definitions:ExplosionA rapid, violent, unconfined combustion, or catastrophic failure of pressurized/energizedequipment that imparts energy of sufficient force to potentially damage permanent structures,systems, or components.FireCombustion characterized by heat and light. Sources of smoke such as slipping drive belts oroverheated electrical equipment do not constitute fires. Observation of flame is preferred but isnot required if large quantities of smoke and heat are observed.Safety-Related Structures, Systems and Components (as defined in 10CFR50.2)Those structures, systems and components that are relied upon to remain functional duringand following design basis events to assure:(1) The integrity of the reactor coolant pressure boundary;(2) The capability to shut down the reactor and maintain it in a safe shutdown condition;(3) The capability to prevent or mitigate the consequences of accidents which could resultin potential offsite exposures.Visible DamageDamage to equipment or structure that is readily observable without measurements, testing, oranalysis. Damage is sufficient to cause concern regarding the continued operability or reliabilityof affected safety structure, system, or component. Example damage includes: deformationdue to heat or impact, denting, penetration, rupture, cracking, paint blistering. Surfaceblemishes (e.g., paint chipping, scratches) should not be included.February 2016 153 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexFvcInn ...................... m m CCNPP Basis Reference(s):1. Drawing 61502 Plant Property and Buildings2. UFSAR Section 5A.2 Classes of Structures, Systems, and Equipment3. NEI 99-01 HA2February 2016154EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexEYAlnn NuclearCategory:H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 3 -Hazardous GasInitiating Condition: Release of toxic, corrosive, asphyxiant or flammable gasesdeemed detrimental to normal plant operationsEAL:SHU3.1Unusual EventIToxic, corrosive, asphyxiant or flammable gases in amounts that have or could adverselyaffect NORMAL PLANT OPERATIONSMode Applicability:-AllBasis:GenericThis EAL is based on the release of toxic, corrosive, asphyxiant or flammable gases of sufficientquantity to affect normal plant operations.The fact that SCBA may be worn does not eliminate the need to declare the event.This EAL is not intended to require significant assessment or quantification. It assumes anuncontrolled process that has the potential to affect plant operations. This would preclude small orincidental releases, or releases that do not impact structures needed for plant operation.An asphyxiant is a gas capable of reducing the level of oxygen in the body to dangerous levels.Most commonly, asphyxiants work by merely displacing air in an enclosed environment. Thisreduces the concentration of oxygen below the normal level of around 19%, which can lead tobreathing difficulties, unconsciousness or even death.Escalation of this emergency classification level, if appropriate, would be based on EAL HA3.1.Plant-SpecificAsphyxiant gases include carbon dioxide, smoke, etc.Definitions:Normal Plant OperationsActivities at the plant site associated with routine testing, maintenance, or equipmentoperations, in accordance with normal operating or administrative procedures. Entry intoabnormal or emergency operating procedures, or deviation from normal security or radiologicalcontrols posture, is a departure from Normal Plant Operations.February 2016155EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryExelon NuclearCalvert Cliffs AnnexCCNPP Basis Reference(s):1. NEI 99-01 HU3February 2016156EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/Proprietary('zlvprt CliffR AnncxFYAIlnn N~ir~nlnrCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 3 -Hazardous GasInitiating Condition: Release of toxic, corrosive, asphyxiant or flammable gasesdeemed detrimental to normal plant operationsEAL:SHU3.2 Unusual EventRecommendation by local, county or state officials to evacuate or shelter site personnelbased on offsite eventMode Applicability:AllBasis:GenericEscalation of this emergency classification level, if appropriate, would be based on EAL HA3. 1.Plant-SpecificNoneCCNPP Basis Reference(s):1. NEI 99-01 HU3February 2016157EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexIFxelon Nurlea~rCategory:Subcategory:H -Hazards and Other Conditions Affecting Plant Safety3 -Hazardous GasInitiating Condition: Access to a Vital Area is prohibited due to toxic, corrosive,asphyxiant or flammable gases which jeopardize operation ofoperable equipment required to maintain safe operations or safelyshutdown the reactorEAL:HA3.1 AlertAccess to ANY of the following areas is prohibited due to toxic, corrosive, asphyxiant orflammable gases (Note 5):* Control Room* 45' West Electrical Penetration Rooms* 69' Electrical Penetration Rooms* ECCS Pump Rooms* Charging Pump Rooms* Component Cooling RoomsNote 5: If the equipment in the stated area was already inoperable, or out of service, before the event occurred, thenEAL HA3.1 should not be declared as it will have no adverse impact on the ability of the plant to safelyoperate or safely shutdown beyond that already allowed by Technical Specifications at the time of the event.Mode Applicability:AllBasis:GenericGases in a Vital Area can affect the ability to safely operate or safely shutdown the reactor.The fact that SCBA may be worn does not eliminate the need to declare the event.Declaration should not be delayed for confirmation from atmospheric testing if the atmosphereposes an immediate threat to life and health or an immediate threat of severe exposure to gases.This could be based upon documented analysis, indication of personal ill effects from exposure, oroperating experience with the hazards.If the equipment in the stated area was already inoperable, or out of service, before the eventoccurred, then this EAL should not be declared as it will have no adverse impact on the ability ofthe plant to safely operate or safely shutdown beyond that already allowed by TechnicalSpecifications at the time of the event.February 2016158EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexlEYAInn Nuinl~sr................ i I An asphyxiant is a gas capable of reducing the level of oxygen in the body to dangerous levels.Most commonly, asphyxiants work by merely displacing air in an enclosed environment. Thisreduces the concentration of oxygen below the normal level of around 19%, which can lead tobreathing difficulties, unconsciousness or even death.An uncontrolled release of flammable gasses within a facility structure has the potential to affectsafe operation of the plant by limiting either operator or equipment operations due to the potentialfor ignition and resulting equipment damage/personnel injury. Flammable gasses, such ashydrogen and acetylene, are routinely used to maintain plant systems (hydrogen) or to repairequipment/components (acetylene -used in welding). This EAL assumes concentrations offlammable gasses which can ignite/support combustion.Escalation of this emergency classification level, if appropriate, will be based on EALs in CategoryS, Category F or Category R.Plant-SpecificLocations designated in the EAL are those areas that are required for Cold Shutdown that cannotbe completed from the Control Room.CCNPP Basis Reference(s):1. NEI 99-01 HA3February 2016159EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryC~lvnrt An n~xN=iilcI:2ry Vi v III IV I II II iVel iWMVIV1/41Category:Su bcateg ory:H -Hazards and Other Conditions Affecting Plant Safety4 -SecurityInitiating Condition: Confirmed security condition or threat which indicates a potentialdegradation in the level of safety of the plantEAL:HU4.1 Unusual EventA SECURITY CONDITION that does not involve a HOSTILE ACTION as reported bySecurity Shift SupervisorORA credible site-specific security threat notificationORA validated notification from NRC providing information of an aircraft threatMode Applicability:AllBasis:GenericNote: Timely and accurate communication between Security Shift Supervision and the ControlRoom is crucial for the implementation of effective Security EALs.Security events which do not represent a potential degradation in the level of safety of the plant arereported under 10 CFR 73.71 or in some cases under 10 CFR 50.72. Security events assessed ashostile actions are classifiable under EAL HA4.1, EAL HS4.1 and EAL HG4.1.A higher initial classification could be made based upon the nature and timing of the security threatand potential consequences. The licensee shall consider upgrading the emergency responsestatus and emergency classification level in accordance with the CCNPP Security and SafeguardsContingency Plan.First ConditionReference is made to the security shift supervisor because these individuals are the designatedpersonnel on-site qualified and trained to confirm that a security event is occurring or has occurred.Training on security event classification confirmation is closely controlled due to the strict secrecycontrols placed on the plant Security and Safeguards Contingency Plan.This threshold is based on the CCNPP Security and Safeguards Contingency Plan. The CCNPPSecurity and Safeguards Contingency Plan is based on guidance provided by NEI 03-12.February 2016160EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearSecond ConditionThis threshold is included to ensure that appropriate notifications for the security threat are made ina timely manner. This includes information of a credible threat. Only the plant to which the specificthreat is made need declare the Unusual Event.The determination of "credible" is made through use of information found in the CCNPP Securityand Safeguards Contingency Plan.Third ConditionThe intent of this EAL is to ensure that notifications for the aircraft threat are made in a timelymanner and that Offsite Response Organizations and plant personnel are at a state of heightenedawareness regarding the credible threat. It is not the intent of this EAL to replace existing non-hostile related EALs involving aircraft.This EAL is met when a plant receives information regarding an aircraft threat from NRC.Validation is performed by calling the NRC or by other approved methods of authentication. Onlythe plant to which the specific threat is made need declare the Unusual Event.The NRC Headquarters Operations Officer (HOO) will communicate to the licensee if the threatinvolves an airliner (airliner is meant to be a large aircraft with the potential for causing significantdamage to the plant). The status and size of the plane may be provided by NORAD through theNRC.Escalation to Alert emergency classification level via EAL HA4. 1 would be appropriate if the threatinvolves an airliner within 30 minutes of the plant.Plant-SpecificIf the Security Shift Supervisor determines that a threat notification is credible, the Security ShiftSupervisor will notify the Operations Shift Manager that a "Credible Threat" condition exists forCalvert Cliffs. Generally, Calvert Cliffs Security Procedures address standard practices fordetermining credibility. The three main criteria for determining credibility are: technical feasibility,operational feasibility, and resolve. For Calvert Cliffs, a validated notification delivered by the FBI,NRC or similar agency is treated as credible.Definitions:AirlinerlLarge AircraftAny size or type of aircraft with the potential for causing significant damage to the plant (refer tothe Security Plan for a more detailed definition).February 2016 161 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearHostile ActionAn act toward CON PP or its personnel that includes the use of violent force to destroyequipment, take hostages, and/or intimidate the licensee to achieve an end. This includesattack by air, land, or water using guns, explosives, projectiles, vehicles, or other devices usedto deliver destructive force. Other acts that satisfy the overall intent may be included.Hostile Action should not be construed to include acts of civil disobedience or felonious actsthat are not part of a concerted attack on CCNPP. Non-terrorism-based EALs should be usedto address such activities, (e.g., violent acts between individuals in the owner controlled area).Security ConditionAny security event as listed in the approved security contingency plan that constitutes athreat/compromise to site security, threat/risk to site personnel, or a potential degradation to thelevel of safety of the plant. A~security condition does not involve a hostile action.CCNPP Basis Reference(s):1. CCNPP Security and Safeguards Contingency Plan2. NEI 99-01 HU4February 2016162EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryrlvIrt AnnmeFvI::nn rCategory:S ubcateg ory:H -Hazards and Other Conditions Affecting Plant Safety4 -SecurityInitiating Condition: Hostile action within the Owner Controlled Area or airborne attackthreatEAL:HA4.1 AlertA HOSTILE ACTION is occurring or has occurred within the Owner Controlled Area asreported by Security Shift SupervisorORA validated notification from NRC of an AIRLINER attack threat within 30 min. of the siteMode Applicability:AllBasis:GenericNote: Timely and accurate communication between Security Shift Supervision and the ControlRoom is crucial for the implementation of effective Security EALs.This EAL addresses the contingency for a very rapid progression of events, such as thatexperienced on September 11, 2001. They are not premised solely on the potential for aradiological release. Rather the issue includes the need for rapid assistance due to the possibilityfor significant and indeterminate damage from additional air, land or water attack elements.The fact that the site is under serious attack or is an identified attack target with minimal timeavailable for further preparation or additional assistance to arrive requires a heightened state ofreadiness and implementation of protective measures that can be effective (such as on-siteevacuation, dispersal or sheltering).First ConditionThis condition addresses the potential for a very rapid progression of events due to a hostileaction. It is not intended to address incidents that are accidental events or acts of civildisobedience, such as small aircraft impact, hunters, or physical disputes between employeeswithin the Owner Controlled Area. Those events are adequately addressed by other EALs.Note that this condition is applicable for any hostile action occurring, or that has occurred, in theOwner Controlled Area including the Independent Spent Fuel Storage Installation (ISFSI).February 2016163EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearSecond ConditionThis condition addresses the immediacy of an expected threat arrival or impact on the site within arelatively short time.The intent of this condition is to ensure that notifications for the airliner attack threat are made in atimely manner and that Offsite Response Organizations (OROs) and plant personnel are at a stateof heightened awareness regarding the credible threat. Airliner is meant to be a large aircraft withthe potential for causing significant damage to the plant.This condition is met when a plant receives information regarding an airliner attack threat fromNRC and the airliner is within 30 minutes of the plant. Only the plant to which the specific threat ismade need declare the Alert.The NRC Headquarters Operations Officer (HOO) will communicate to the licensee if the threatinvolves an airliner (airliner is meant to be a large aircraft with the potential for causing significantdamage to the plant). The status and size of the plane may be provided by NORAD through theNRC.Plant-SpecificDefinitions:Airliner/Large AircraftAny size or type of aircraft with the potential for causing significant damage to the plant (refer tothe Security Plan for a more detailed definition).Hostile ActionAn act toward CCNPP or its personnel that includes the use of violent force to destroyequipment, take hostages, and/or intimidate the licensee to achieve an end. This includesattack by air, land, or water using guns, explosives, projectiles, vehicles, or other devices usedto deliver destructive force. Other acts that satisfy the overall intent may be included.Hostile Action should not be construed to include acts of civil disobedience or felonious actsthat are not part of a concerted attack on CCNPP. Non-terrorism-based EALs should be usedto address such activities, (e.g., violent acts between individuals in the owner controlled area).CCNPP Basis Reference(s):1. CCNPP Security and Safeguards Contingency Plan2. NEI 99-01 HA4February 2016 164 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexIExelon Nurlea~r...................... m ...............Category:Subcategory:H -Hazards and Other Conditions Affecting Plant Safety4 -SecurityInitiating Condition: Hostile action within the Protected AreaEAL:HS4.1 Site Area EmergencyA HOSTILE ACTION is occurring or has occurred within the PROTECTED AREA asreported by Security Shift SupervisorMode Applicability:AllBasis:GenericThis condition represents an escalated threat to plant safety above that contained in the Alert inthat a hostile force has progressed from the Owner Controlled Area to the Protected Area.This EAL addresses the contingency for a very rapid progression of events, such as thatexperienced on September II, 2001. It is not premised solely on the potential for a radiologicalrelease. Rather the issue includes the need for rapid assistance due to the possibility for significantand indeterminate damage from additional air, land or water attack elements.The fact that the site is under serious attack with minimal time available for further preparation oradditional assistance to arrive requires Offsite Response Organization (ORO) readiness andpreparation for the implementation of protective measures.This EAL addresses the potential for a very rapid progression of events due to a hostile action. It isnot intended to address incidents that are accidental events or acts of civil disobedience, such assmall aircraft impact, hunters, or physical disputes between employees within the Protected Area.Those events are adequately addressed by other EALs.Escalation of this emergency classification level, if appropriate, would be based on actual plantstatus after impact or progression of attack.Plant-SpecificA hostile action that occurs or has occurred within the ISESI area is not classified under this EAL.The ISESI is located in the OCA and hostile action occurring in the ISESI would be classified underHA4.1. If hostile action in the ISESI results in damage to a cask confinement boundary, the eventwould meet the Unusual Event classification threshold for EAL EUI .1 as well as HA4.1.February 2016165EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearDefinitions:Hostile ActionAn act toward CCNPP or its personnel that includes the use of violent force to destroyequipment, take hostages, and/or intimidate the licensee to achieve an end. This includesattack by air, land, or water using guns, explosives, projectiles, vehicles, or other devices usedto deliver destructive force. Other acts that satisfy the overall intent may be included.Hostile Action should not be construed to include acts of civil disobedience or felonious actsthat are not part of a concerted attack on CCNPP. Non-terrorism-based EALs should be usedto address such activities, (e.g., violent acts between individuals in the owner controlled area).Protected AreaThe site specific area which normally encompasses all controlled areas within the securityProtected Area fence.CCNPP Basis Reference(s):1. CCNPP Security and Safeguards Contingency Plan2. NEI 99-01 HS4February 2016166EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:H -Hazards and Other Conditions Affecting Plant Safety4 -SecurityInitiating Condition: Hostile action resulting in loss of physical control of the facilityEAL:HG4.1 General EmergencyA HOSTILE ACTION has occurred such that plant personnel are unable to operateequipment required to maintain ANY of the following safety function acceptance criteria:* Reactivity control (RC)* Vital Auxiliaries (VA)* RCS pressure and inventory control (PlC)* Core & RCS heat removal (HR)Mode Applicability:AllBasis:GenericThis EAL encompasses conditions under which a hostile action has resulted in a loss of physicalcontrol of Vital Areas (containing vital equipment or controls of vital equipment) required tomaintain safety functions and control of that equipment cannot be transferred to and operated fromanother location.If control of the plant equipment necessary to maintain safety functions can be transferred toanother location, then the threshold is not met.Plant-SpecificSafety functions of concern in this EAL include:* Reactivity control* RCS inventory control* ROS pressure control* Core & RCS heat removalThese safety functions are maintained by meeting the relevant EOP Safety Function AcceptanceCriteria (ref. 1).February 2016167EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearDefinitions:Hostile ActionAn act toward CCN PP or its personnel that includes the use of violent force to destroyequipment, take hostages, and/or intimidate the licensee to achieve an end. This includesattack by air, land, or water using guns, explosives, projectiles, vehicles, or other devices usedto deliver destructive force. Other acts that satisfy the overall intent may be included.Hostile Action should not be construed to include acts of civil disobedience or felonious actsthat are not part of a concerted attack on CCNPP. Non-terrorism-based EALs should be usedto address such activities, (e.g., violent acts between individuals in the owner controlled area).CCNPP Basis Reference(s):1. CCNPP Security and Safeguards Contingency Plan2. CEN-152 Combustion Engineering Emergency Procedure Guidelines3. NEI 99-01 HG1February 2016168EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 4 -SecurityInitiating Condition: Hostile action resulting in loss of physical control of the facilityEAL:HG4.2 General EmergencyA HOSTILE ACTION has caused failure of Spent Fuel Cooling systemsANDIMMINENT fuel damage is likelyMode Applicability:AllBasis:GenericThis EAL addresses failure of spent fuel cooling systems as a result of hostile action if imminentfuel damage is likely.Plant-SpecificDefinitions:Hostile ActionAn act toward CCNPP or its personnel that includes the use of violent force to destroyequipment, take hostages, and/or intimidate the licensee to achieve an end. This includesattack by air, land, or water using guns, explosives, projectiles, vehicles, or other devices usedto deliver destructive force. Other acts that satisfy the overall intent may be included.Hostile Action should not be construed to include acts of civil disobedience or felonious actsthat are not part of a concerted attack on CCNPP. Non-terrorism-based EALs should be usedto address such activities, (e.g., violent acts between individuals in the owner controlled area).ImminentMitigation actions have been ineffective, additional actions are not expected to be successful,and trended information indicates that the event or condition will occur. Where imminenttimeframes are specified, they shall apply.CCNPP Basis Reference(s):1. CCNPP Security and Safeguards Contingency Plan2. NEI 99-01 HGIFebruary 2016169EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 5 -Control Room EvacuationInitiating Condition: Control Room evacuation has been initiatedEAL:HA5.1 AlertControl Room evacuation has been initiatedMode Applicability:AllBasis:GenericWith the Control Room evacuated, additional support, monitoring and direction through theTechnical Support Center and/or other emergency response facilities may be necessary.Inability to establish plant control from outside the Control Room will escalate this event to a SiteArea Emergency.Plant-SpecificAOP-9A Control Room Evacuation and Safe Shutdown Due to a Severe Control Room Fire andAOP-1 1 Control Room Evacuation and Safe Shutdown -Non-Fire Conditions provide specificinstructions for evacuating the Control Room/Building and establishing plant control in alternatelocations.CCNPP Basis Reference(s):1. AOP-9A Control Room Evacuation and Safe Shutdown Due to a Severe Control Room Fire2. AOP-11I Control Room Evacuation and Safe Shutdown -Non-Fire Conditions3. NEI 99-01 HA5February 2016170EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryAnnmrFYAlnn NIclIa~rVR m Wl ..... Im mm I m Category:Subcategory:H -Hazards and Other Conditions Affecting Plant Safety5 -Control Room EvacuationInitiating Condition: Control Room evacuation has been initiated and plant controlcannot be establishedEAL:HS5.1 Site Area EmergencyControl Room evacuation has been initiated AND EITHER:Inability to establish Auxiliary Feedwater to at least one steam generator within 30 mai.(Note 4)ORInability to establish reactor coolant make-up (charging pump flow) within 60 min. (Note4)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soonas it is determined that the condition has exceeded, or will likely exceed, the applicable time.Mode Applicability:AllBasis:GenericThe intent of this EAL is to capture those events where control of the plant cannot be reestablishedin a timely manner. In this case, expeditious transfer of control of safety systems has not occurred(although fission product barrier damage may not yet be indicated).The intent of the EAL is to establish control of important plant equipment and knowledge ofimportant plant parameters in a timely manner. Primary emphasis should be placed on thosecomponents and instruments that supply protection for and information about safety functions.Typically, these safety functions are reactivity control (ability to shutdown the reactor and maintainit shutdown), reactor water level (ability to cool the core), and decay heat removal (ability tomaintain a heat sink).The determination of whether or not control is established at the remote shutdown panel is basedon Emergency Director (ED) judgment. The Emergency Director is expected to make a reasonable,informed judgment within the site specific time for transfer that the licensee has control of the plantfrom the remote shutdown panel.Escalation of this emergency classification level, if appropriate, would be by EALs in Category F orCategory R.February 2016171EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearPlant-SpecificAOP-9A Control Room Evacuation and Safe Shutdown Due to a Severe Control Room Fire andAOP-11I Control Room Evacuation and Safe Shutdown -Non-Fire Conditions provide specificinstructions for evacuating the Control Room/Building and establishing plant control in alternatelocations.An analysis was performed to determine how quickly control must be re-established at CCNPPwithout core uncovery or damage. A RETRAN simulation shows that the steam generators go dryat about 4"7 minutes for the AOP-9 (station fire) scenario. ROS pressure reaches the lowestpressurizer safety valve setpoint soon thereafter. Restoring feedwater within 45 minutes assuresthat RCS pressure remains below the safety valve setpoint thus avoiding inventory loss. Themaximum time allowable to restore RCS inventory for Appendix R (station fire) scenarios is 90minutes. Site Emergency declaration at 30 minutes and 60 minutes for inability to restorefeedwater and RCS make-up respectively thus constitutes a conservative action for emergencyresponse.This EAL is based on analysis and actual procedure walk throughs. Licensee Event Report (LER)50-371/89-009, Rev. 2, (transmitted to the NRC on July 7, 1989) documents the analysis thatdemonstrates the ability to safely shutdown Unit I in accordance with AOP-9.CCNPP Basis Reference(s)::1. AOP-9A Control Room Evacuation and Safe Shutdown Due to a Severe Control Room Fire2. AOP-11I Control Room Evacuation and Safe Shutdown -Non-Fire Conditions3. Letter, L.B. Russell (BG&E) to James H. Joyner (U.S. Nuclear Regulatory CommissionRegion I), Emergency Action Level Review Meeting, June 6, 19914. NEI 99-01 HS2February 2016 172 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:S ubcateg ory:H -Hazards and Other Conditions Affecting Plant Safety6 -JudgmentInitiating Condition: Other conditions existing that in the judgment of the EmergencyDirector warrant declaration of a UEEAL:HU6.1 Unusual EventOther conditions exist which in the judgment of the Emergency Director indicate thatevents are in progress or have occurred which:Indicate a potential degradation of the level of safety of the plantORIndicate a security threat to facility protection has been initiatedNo releases of radioactive material requiring offsite response or monitoring are expectedunless further degradation of safety systems occursMode Applicability:AllBasis:GenericThis EAL addresses unanticipated conditions not addressed explicitly elsewhere but that warrantdeclaration of an emergency because conditions exist which are believed by the EmergencyDirector to fall under the UE emergency classification level.Plant-SpecificNoneCCNPP Basis Reference(s):1. NEI 99-01 HU5February 2016173EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:H -Hazards and Other Conditions Affecting Plant Safety6 -JudgmentInitiating Condition: Other conditions exist that in the judgment of the EmergencyDirector warrant declaration of an AlertEAL:HA6.1 AlertOther conditions exist which in the judgment of the Emergency Director indicate thatevents are in progress or have occurred which involve:An actual or potential substantial degradation of the level of safety of the plantORA security event that involves probable life threatening risk to site personnel or damageto site equipment because of HOSTILE ACTIONANY releases are expected to be limited to small fractions of the EPA Protective ActionGuideline exposure levels (1,000 mRem TEDE and 5,000 mRem thyroid CDE)Mode Applicability:AllBasis:GenericThis EAL addresses unanticipated conditions not addressed explicitly elsewhere but that warrantdeclaration of an emergency because conditions exist which are believed by the EmergencyDirector to fall under the Alert emergency classification level.Plant-SpecificDefinitions:Hostile ActionAn act toward CCNPP or its personnel that includes the use of violent force to destroyequipment, take hostages, and/or intimidate the licensee to achieve an end. This includesattack by air, land, or water using guns, explosives, projectiles, vehicles, or other devices usedto deliver destructive force. Other acts that satisfy the overall intent may be included.Hostile Action should not be construed to include acts of civil disobedience or felonious actsthat are not part of a concerted attack on CCNPP. Non-terrorism-based EALs should be usedto address such activities, (e.g., violent acts between individuals in the owner controlled area).February 2016174EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexCCNPP Basis Reference(s):1. NEI 99-01 HA6Exelon NuclearFebruary 2016175EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:H -Hazards and Other Conditions Affecting Plant Safety6 -JudgmentInitiating Condition: Other conditions existing that in the judgment of the EmergencyDirector warrant declaration of a Site Area EmergencyEAL:HS6.1 Site Area EmergencyOther conditions exist which in the judgment of the Emergency Director indicate thatevents are in progress or have occurred which involve:Actual or likely major failures of plant functions needed for protection of the publicORHOSTILE ACTION that results in intentional damage or malicious acts; (1) toward sitepersonnel or equipment that could lead to the likely failure of or; (2) that preventeffective access to equipment needed for the protection of the publicANY releases are not expected to result in exposure levels which exceed EPA ProtectiveAction Guideline exposure levels (1,000 mRem TEDE and 5,000 mRem thyroid CDE)beyond the site boundaryMode Applicability:AllBasis:GenericThis EAL addresses unanticipated conditions not addressed explicitly elsewhere but that warrantdeclaration of an emergency because conditions exist which are believed by the EmergencyDirector to fall under the emergency classification level description for Site Area Emergency.Plant-Sp~ecificDefinitions:Hostile ActionAn act toward CCNPP or its personnel that includes the use of violent force to destroyequipment, take hostages, and/or intimidate the licensee to achieve an end. This includesattack by air, land, or water using guns, explosives, projectiles, vehicles, or other devices usedto deliver destructive force. Other acts-that satisfy the overall intent may be included.Hostile Action should not be construed to include acts of civil disobedience or felonious actsthat are not part of a concerted attack on CCNPP. Non-terrorism-based EALs should be usedto address such activities, (e.g., violent acts between individuals in the owner controlled area).February 2016176EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryExelon NuclearCalvert Cliffs AnnexCCNPP Basis Reference(s):1. NEI 99-01 HS3February 2016177EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCnlvert Cliffs AnnexI-xAlnn N~mlA~r.... ............... m m Category:H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 6 -JudgmentInitiating Condition: Other conditions exist that in the judgment of the EmergencyDirector warrant declaration of a General EmergencyEAL:HG6.1 General EmergencyOther conditions exist which in the judgment of the Emergency Director indicate thatevents are in progress or have occurred which involve:Actual or IMMINENT substantial core degradation or melting with potential for loss ofContainment integrityORHOSTILE ACTION that results in an actual loss of physical control of the facility.Releases can be reasonably expected to exceed EPA Protective Action Guidelineexposure levels (1,000 mRem TEDE and 5,000 mRem thyroid CDE) offsite for more thanthe immediate site areaMode Applicability:AllBasis:GenericThis EAL addresses unanticipated conditions not addressed explicitly elsewhere but that warrantdeclaration of an emergency because conditions exist which are believed by the EmergencyDirector to fall under the emergency classification level description for General Emergency.Plant-SpecificDefinitions:Hostile ActionAn act toward CCNPP or its personnel that includes the use of violent force to destroyequipment, take hostages, and/or intimidate the licensee to achieve an end. This includesattack by air, land, or water using guns, explosives, projectiles, vehicles, or other devices usedto deliver destructive force. Other acts that satisfy the overall intent may be included.Hostile Action should not be construed to include acts of civil disobedience or felonious actsthat are not part of a concerted attack on CCNPP. Non-terrorism-based EALs should be usedto address such activities, (e.g., violent acts between individuals in the owner controlled area).February 2016178EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearImminentMitigation actions have been ineffective, additional actions are not expected to be successful,and trended information indicates that the event or condition will occur. Where imminenttimeframes are specified, they shall apply.CCNPP Basis Reference(s):1. NEI 99-01 HG2February 2016179EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory S -System MalfunctionEAL Group: Hot Conditions (RCS temperature > 2000F); EALsin this category are applicable only in one or morehot operating modes. Numerous system-relatedequipment failure events that warrant emergency classification have been identified in thiscategory. They may pose actual or potential threats to plant safety.The events of this category pertain to the following subcategories:1. Loss of AC PowerLoss of emergency plant electrical power can compromise plant safety system operabilityincluding decay heat removal and emergency core cooling systems which may be necessary toensure fission product barrier integrity. This category includes loss of onsite and offsite powersources for the 4 kV safeguard buses.2. Loss of DC PowerLoss of emergency plant electrical power can compromise plant safety system operabilityincluding decay heat removal and emergency core cooling systems which may be necessary toensure fission product barrier integrity. This category includes loss of power to the 125 VDCbuses.3. Criticality & RPS FailureInadvertent criticalities pose potential personnel safety hazards as well being indicative oflosses of reactivity control.Events related to failure of the Reactor Protection System (RPS) to initiate and completereactor trips. In the plant licensing basis, postulated failures of the RPS to complete a reactortrip comprise a specific set of analyzed events referred to as Anticipated Transient WithoutScram (ATWS) events. For EAL classification however, ATWS is intended to mean any tripfailure event that does not achieve reactor shutdown. If RPS actuation fails to assure reactorshutdown, positive control of reactivity is at risk and could cause a threat to fuel clad, RCS andContainment integrity.February 2016 180 EP-AA-1O11 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclear4. Inability to Reach or Maintain Shutdown ConditionsSystem malfunctions may lead to failure of the plant to be brought to the required plantoperating condition required by technical specifications if a limiting condition for operation(LCO) is not met.5. InstrumentationCertain events that degrade plant operator ability to effectively assess plant conditions withinthe plant warrant emergency classification. Losses of annunciators are in this subcategory.6. CommunicationsCertain events that degrade plant operator ability to effectively communicate with essentialpersonnel within or external to the plant warrant emergency classification.7. Fuel Clad DegqradationDuring normal operation, reactor coolant fission product activity is very low. Smallconcentrations of fission products in the coolant are primarily from the fission of tramp uraniumin the fuel clad or minor perforations in the clad itself. Any significant increase from these base-line levels (2% -5% clad failures) is indicative of fuel failures and is covered under Category F,Fission Product Barrier Degradation. However, lesser amounts of clad damage may result incoolant activity exceeding Technical Specification limits. These fission products will becirculated with the reactor coolant and can be detected by coolant sampling and/or the Letdownradiation monitor.8. RCS LeakaqeThe Reactor Vessel provides a volume for the coolant that covers the reactor core. TheReactor Vessel and associated pressure piping (reactor coolant system) together provide abarrier to limit the release of radioactive material should the reactor fuel clad integrity fail.Excessive RCS leakage greater than Technical Specification limits are utilized to indicatepotential pipe cracks that may propagate to an extent threatening fuel clad, RCS andContainment integrity.February 2016 181 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory: S -System MalfunctionSubcategory: 1 -Loss of AC PowerInitiating Condition: Loss of all offsite AC power to 4kV vital buses for_> 15 min.EAL:SUI.I Unusual EventLoss of all offsite AC power, Table S-I, to 4kV vital buses 11(21) and 14(24) for >_ 15 min.(Note 4)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time,Table S-I AC Power Sources* 1(2)A DG*) 1(2)B DG* 0C DG, if aligned* 500kV transmission line 5051** 500kV transmission line 5052** 500kV transmission line 5072*o

• SMECO line ,if aligned* A credited 500kV line must have anindependent 13kV service transformerMode Applicability:1 -Power Operation, 2 -Basis:GenericStartup, 3 -Hot Standby, 4 -Hot ShutdownProlonged loss of off-site AC power reduces required redundancy and potentially degrades thelevel of safety of the plant by rendering the plant more vulnerable to a complete loss of AC powerto emergency busses.Fifteen minutes was selected as a threshold to exclude transient or momentary losses of off-sitepower.February 2016182EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearPlant-SpecificCCNPP essential buses are 4kV vital buses 11 (21) and 14(24). There are five offsite powersources available to these buses:* Three 500kV transmission lines (Lines 5051, 5052, and 5072) supply offsite power to the500kV switchyard via the transmission network.*One 69kV/I13kV Southern Maryland Electric Cooperative (SMECO) line may be manuallyconnected to either 13kV bus and then to the 4kV vital buses. Under certain operationalconditions, 13kV bus(es) may be receiving power from SMECO or may be quicklyconnected to the SMECO tie-line. The SMECO line is not used to carry loads for anoperating unit and may provide power to no more than two 4kV vital buses simultaneously.*If a fault affects only one unit, power may be obtained from the 500kV supply of theunaffected unit through a single 13kV transformer. This is considered an offsite AC powersource available to the affected unit.Based on operational experience, if the SMECO line or the 0C DG is not already aligned, thesecannot be considered available/capable of supplying the bus due to the time it will take to alignthem. In any case, if this cannot be accomplished within 15 minutes, they are not available and anUnusual Event must be declared.In-house power is fed back from the 500kV ring bus through 2 13kV transformers (designated P-13000-1 and P-I13000-2). Normally P-I13000-1 supplies all of Unit -I (except 14 4kV bus) and 214kV bus. P-I13000-2 supplies all of Unit-2 (except 21 4kV bus) and 14 4kV bus. Either P-I13000 iscapable of supplying all loads on both Units.The fifteen-minute interval was selected as a threshold to exclude transient power losses.CCNPP Basis Reference(s):I. UFSAR Section 8 and Figure 8-12. Technical Specifications LCO 3.8.1 AC Sources-Operating3. Technical Specifications LCO 3.8.9 Distribution Systems-Operating4. STP-O-90 AC Sources and On-site Power Distribution Systems 7 Day Operability Verification5. EOP-2 Loss of Off-site Power6. NEI 99-01 SU1February 2016 183 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryC.al,~rt AnnoyFvI:= nn NI~ rl~r5 VlmilV RliliturA b4qkVlVll Category:Subcategory:Initiating Condition:S -System Malfunction1 -Loss of AC PowerAC power capability to 4kV vital buses reduced to a single powersource for _15 mmn. such that ANY additional single failure wouldresult in a complete loss of all 4kV vital bus powerEAL:SAI.1 AlertAC power capability to 4kV vital buses 11(21) and 14(24) reduced to a single powersource, Table S-1, for_> 15 min. (Note 4)ANDANY additional single power source failure will result in a complete loss of all 4kV vital buspowerNote 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time.Table S-I AC Power Sources* 1(2)A DG*0 1(2)B DGa 0C DG, if aligned* 500kV transmission line 5051** 500kV transmission line 5052** 500kV transmission line 5072*o

• SMECO line, if aligned* A credited 500kV line must have anindependent 13kV service transformerMode Applicability:I -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericThe condition indicated by this EAL is the degradation of the off-site and on-site AC power systemssuch that any additional single failure would result in a complete loss of 4kV vital bus AC power toone or both units. This condition could occur due to a loss of off-site power with a concurrent failureFebruary 2016184EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearof all but one emergency generator to supply power to its emergency busses. Another relatedcondition could be the loss of all off-site power and loss of on-site emergency generators with onlyone train of 4kV vital busses being backfed from the unit main generator, or the loss of on-siteemergency generators with only one train of 4kV vital busses being backfed from off-site power.The subsequent loss of this single power source would escalate the event to a Site AreaEmergency in accordance with EAL SS 1.1.Fifteen minutes was selected as a threshold to exclude transient or momentary losses of power.Plant-SpecificCCNPP essential buses are 4kV vital buses 11(21) and 14(24). There are five offsite powersources available to these buses:*Three 500kV transmission lines (Lines 5051, 5052, and 5072) supply offsite power to the500kV switchyard via the transmission network.*One 69kV/i13kV Southern Maryland Electric Cooperative (SMECO) line may be manuallyconnected to either 13kV bus and then to the 4kV vital buses. Under certain operationalconditions, 13kV bus(es) may be receiving power from SMECO or may be quicklyconnected to the SMECO tie-line. The SMECO line is not used to carry loads for anoperating unit and may provide power to no more than two 4kV vital buses simultaneously.*If a fault affects only one unit, power may be obtained from the 500kV supply of theunaffected unit through a single 13 kV transformer. This is considered an offsite AC powersource available to the affected unit.Based on operational experience, if the SMECO line or the OC DG is not already aligned, thesecannot be considered available/capable of supplying the bus due to the time it will take to alignthem. In any case, if this cannot be accomplished within 15 minutes, they are not available and theappropriate emergency classification must be declared.In-house power is fed back from the 500kV ring bus through 2 13kV transformers (designated P-13000-i and P-I13000-2). Normally P-i13000-1 supplies all of Unit -I (except 14 4KV bus) and 214kV bus. P-I13000-2 supplies all of Unit-2 (except 21 4kV bus) and 14 4kV bus. Either P-I13000 iscapable of supplying all loads on both Units.February 2016 185 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearThere are five onsite AC power sources:* 1ADGforbusll* lB DG for busl14* 2A DG for bus 2l* 2B DG for bus 24* OC DG may be aligned to any vital 4kV bus on either unit.The fifteen-minute interval was selected as a threshold to exclude transient power losses. If thecapability for multiple sources to energize the unit vital buses within 15 minutes is not restored, anAlert is declared under this EAL. The subsequent loss of the single remaining power sourceescalates the event to a Site Area Emergency under EAL SS1.l.CCNPP Basis Reference(s):1. UFSAR Section 8 and Figure 8-12. Technical Specifications LOCO 3.8.1 AC Sources-Operating3. Technical Specifications LCO 3.8.9 Distribution Systems-Operating4. OI-21A-1 1A Diesel Generator5. OI-21A-2 2A Diesel Generator6. OI-21B-1 lB Diesel Generator7. 0I-21 B-2 2B Diesel Generator8. 0I-21C 0C Diesel Generator9. STP-O-90 AC Sources and On-site Power Distribution Systems 7 Day Operability Verification10. AOP-71 Loss of 4kV, 480 Volt, or 208/1 20 Volt Instrument Bus Power11. AOP-3F Loss of Off-site Power While in MODES 3, 4, 5, or 612. EOP-0 Post-trip Immediate Actions13. EOP-2 Loss of Off-site Power14. EOP-7 Station Blackout15. EOP-8 Functional Recovery16. NEI 99-01 SA5February 2016 186 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Su bcateg ory:S -System Malfunction1 -Loss of AC PowerInitiating Condition: Loss of all offsite and all onsite AC power to 4kV vital buses for >15 min.EAL:SS1.1 Site Area EmergencyLoss of all offsite and all onsite AC power, Table S-I, to 4kV vital buses 11(21) and 14(24)for> 15 min. (Note 4)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time.Table S-1 AC Power Sources* 1(2)A DGCo

• 1(2)B DG0 OC DG ,if aligned* 500kV transmission line 5051"* 500kV transmission line 5052**l= 500kV transmission line 5072*O

• SMECO line ,if aligned* A credited 500kV line must have anindependent 13kV service transformerMode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericLoss of all AC power to emergency busses compromises all plant safety systems requiring electricpower including RHR, ECCS, Containment Heat Removal and the Ultimate Heat Sink. Prolongedloss of all AC power to 4kV vital busses will lead to loss of Fuel Clad, RCS, and Containment, thusthis event can escalate to a General Emergency.Fifteen minutes was selected as a threshold to exclude transient or momentary losses of off-sitepower.February 2016187EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearEscalation to General Emergency is via EALs in Category F or EAL SG1 .1.Plant-SpecificThe CCNPP vital buses are 4kV buses 11 (21) and 14(24). There are five offsite power sourcesavailable to these buses:*Three 500kV transmission lines (Lines 5051, 5052, and 5072) supply offsite power to the500kV switchyard via the transmission network.*One 69kV/I13kV Southern Maryland Electric Cooperative (SMECO) line may be manuallyconnected to either vital 13kV bus and then to the 4kV vital buses. Under certainoperational conditions, 13kV bus(es) may be receiving power from SMECO or may bequickly connected to the SMECO tie-line. The SMECO line is not used to carry loads for anoperating unit and may provide power to no more than two 4kV vital buses simultaneously.*If a fault affects only one unit, power may be obtained from the 500kV supply of theunaffected unit through a single 13kV transformer. This is considered an offsite AC powersource available to the affected unit.In-house power is fed back from the 500kV ring bus through 2 13kV transformers (designated P-13000-1 and P-I13000-2). Normally P-13000-l supplies all of Unit -I (except 14 4kV bus) and 214kV bus. P-I13000-2 supplies all of Unit-2 (except 21 4kV bus) and 14 4kV bus. Either P-I13000 iscapable of supplying all loads on both Units.There are five onsite AC power sources:* 1A DG for bus11* 1B DG for busI14* 2A DG for bus 21* 2B DG for bus 24* OC DG may be aligned to any vital 4kV bus on either unit.Based on operational experience, if the SMECO line or the OC DG is not already aligned, thesecannot be considered available/capable of supplying the bus due to the time it will take to alignthem. In any case, if this cannot be accomplished within 15 minutes, they are not available and aSite Area Emergency must be declared.February 2016 188 EP-AA-1011 Addendum 3(Revision I)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearConsideration should be given to operable loads necessary to remove decay heat or provideReactor Vessel makeup capability when evaluating loss of all AC power to vital buses. Eventhough an essential bus may be energized, if necessary loads (i.e., loads that if lost would inhibitdecay heat removal capability or Reactor Vessel makeup capability) are not operable on theenergized bus then the bus should not be considered operable.The fifteen-minute interval was selected as a threshold to exclude transient power losses. If the 00DG is available but is not powering a vital bus within 15 minutes, the EAL remains applicable.CCNPP Basis Reference(s):1. UFSAR Section 8 and Figure 8-12. Technical Specifications LCO 3.8.1 AC Sources-Operating3. Technical Specifications LCO 3.8.9 Distribution Systems-Operating4. OI-21A-1 IA Diesel Generator5. Ol-21A-2 2A Diesel Generator6. Ol-21B-1 lB Diesel Generator7. OI-218-2 2B Diesel Generator8. OI-21C 00 Diesel Generator9. STP-O-90 AC Sources and On-site Power Distribution Systems 7 Day Operability Verification10. AOP-71 Loss of 4kV, 480 Volt, or 208/1 20 Volt Instrument Bus Power11. AOP-3F Loss of Off-site Power While in MODES 3, 4, 5, or 612. EOP-0 Post-trip Immediate Actions13. EOP-2 Loss of Off-site Power14. EOP-7 Station Blackout15. EOP-8 Functional Recovery16. NEI 99-01 SS1February 2016 189 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:S -System MalfunctionSubcategory: 1 -Loss of PowerInitiating Condition: Prolonged loss of all offsite and all onsite AC power to 4kV vitalbusesEAL:SGI.1 General EmergencyLoss of all offsite and all onsite AC power, Table S-I, to 4kV vital buses 11(21) and 14(24)AND EITHER:Restoration of at least one 4kV vital bus within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> is not likelyORGET readings > 700°FTable S-I AC Power Sourceso 1(2)A DGU,

• 1(2)B DGe 00 DG, if alignedo500kV transmission line 5051*e, 500kV transmission line 5052*C,' o 500kV transmission line 5072*O e, SMECO line, if aligned* A credited 500kV line must have anindependent 13kV service transformerMode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericLoss of all AC power to emergency busses compromises all plant safety systems requiring electricpower including RHR, EGGS, Containment Heat Removal and the Ultimate Heat Sink. Prolongedloss of all AC power to emergency busses will lead to loss of fuel clad, RCS, and Containment,thus warranting declaration of a General Emergency.February 2016190EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearThis EAL is specified to assure that in the unlikely event of a prolonged loss of all AC power to vital4kV buses, timely recognition of the seriousness of the event occurs and that declaration of aGeneral Emergency occurs as early as is appropriate, based on a reasonable assessment of theevent trajectory.The likelihood of restoring at least one vital bus should be based on a realistic appraisal of thesituation since a delay in an upgrade decision based on only a chance of mitigating the event couldresult in a loss of valuable time in preparing and implementing public protective actions.In addition, under these conditions, fission product barrier monitoring capability may be degraded.Plant-SpecificThe CCNPP vital buses are 4kV buses 11 (21) and 14(24). There are five offsite power sourcesavailable to these buses:* Three 500kV transmission lines (Lines 5051, 5052, and 5072) supply offsite power to the500kV switchyard via the transmission network.*One 69kV/1 3kV Southern Maryland Electric Cooperative (SMECO) line may be manuallyconnected to either vital 13kV bus and then to the 4kV vital buses. Under certainoperational conditions, 13kV bus(es) may be receiving power from SMECO or may bequickly connected to the SMECO tie-line. The SMECO line is not used to carry loads for anoperating unit and may provide power to no more than two 4kV vital buses simultaneously.*If a fault affects only one unit, power may be obtained from the 500kV supply of theunaffected unit through a single 13kV transformer. This is considered an offsite AC powersource available to the affected unit.In-house power is fed back from the 500kV ring bus through 2 13kV transformers (designated P-13000-1 and P-i13000-2). Normally P-I13000-1 supplies all of Unit -I (except 14 4kV bus) and 214kV bus. P-13000-2 supplies all of Unit-2 (except 21 4kV bus) and 14 4kV bus. Either P-I13000 iscapable of supplying all loads on both Units.There are five onsite AC power sources:* 1A DG for bus11* 1B DG for bus14* 2A DG for bus 21* 2B DG for bus 24February 2016 191 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclear* 00 DG may be aligned to any vital 4kV bus on either unit.Consideration should be given to operable loads necessary to remove decay heat or provideReactor Vessel makeup capability when evaluating loss of all AC power to vital buses. Eventhough a vital bus may be energized, if necessary loads (i.e., loads that if lost would inhibit decayheat removal capability or Reactor Vessel makeup capability) are not operable on the energizedbus then the bus should not be considered operable.CCNPP is licensed both for a four hour SBO coping category and a one hour 580 copingcategory. The ability of each unit to cope with a four hour 580 duration was based on anassessment of condensate inventory required for decay heat removal, Class 1 E battery capacity,compressed air availability or manual operation of certain valves, effects of loss of ventilation,Containment isolation valve operability, and reactor coolant inventory loss. A plant-specific analysisindicates that the expected rates of reactor coolant inventory loss under 5B0 conditions do notresult in core uncovery in a 5B0 for four hours. Therefore, makeup systems in addition to thosecurrently available under 5B0 conditions are not required to maintain core cooling under naturalcirculation (including reflux cooling). Thus, conditions in which restoration of AC power within fourhours is not likely are included in the EAL.Installation of the SBO diesel allowed CCNPP to operate as a plant having a one hour copingcapability. This allowance is in recognition that sufficient diesel generator back-up reduces thelikelihood of station blackout. The analysis for the four hour coping category however, provides thesource of the appropriate estimate of the time to core uncovery following 580 from which the plantcannot recover. This time (four hours) is therefore used as the basis for determining when todeclare a General Emergency subsequent to a prolonged 580.Core Exit Thermocouples (CETs) are a component of the Inadequate Core CoolingInstrumentation and provide an indirect indication of fuel clad temperature by measuring thetemperature of the reactor coolant that leaves the core region. A superheat condition is indicatedby CET readings above 700°F. The RCS Pressure Safety Limit is 2750 psia per CCNPP TechnicalSpecifications. The saturation temperature for this pressure is 682.2°F. Per Action Value BasesDocument EOP-24.33, the uncertainty on CET Temperature is +/- 39.8°F. If one or more CETsindicate 7220F (682.2 + 39.8), subcooling has been lost for at least some locations in the core.CET indications at or above 7220°F are a clear sign that core heat removal capability is lost orgreatly reduced and one fission product barrier, the fuel clad, is threatened due to elevated fuelFebruary 2016 192 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nucleartemperatures. 700°F qualifies as a condition representing a potential loss of the fuel clad barrier(ref. 16).CCNPP Basis Reference(s):1. UFSAR Section 8 and Figure 8-12. Technical Specifications LCO 3.8.1 AC Sources-Operating3. Technical Specifications LCO 3.8.9 Distribution Systems-Operating4. OI-21lA-I 1A Diesel Generator5. Ol-21A-2 2A Diesel Generator6. OI-21B-I lB Diesel Generator7. OI-21B-2 2B Diesel Generator8. Ol-21C OC Diesel Generator9. STP-~O-90 AC Sources and On-site Power Distribution Systems 7 Day Operability Verification10. AOP-71 Loss of 4kV, 480 Volt, or 208/1 20 Volt Instrument Bus Power11. AOP-3F Loss of Off-site Power While in MODES 3, 4, 5, or 612. EOP-0 Post-trip Immediate Actions13. EOP-2 Loss of Off-site Power14. EOP-7 Station Blackout15. EOP-8 Functional Recovery16. EOP-24.33 Action Value Bases Document17. ERPIP-800 Core Damage Assessment18. ERPIP-802 Core Damage Assessment Using Core Exit Thermocouples19. EOP-5 Loss of Coolant Accident20. CEN-152 Emergency Procedure Guidelines21. OP-7 Shutdown Operations22. ERPIP-601 Severe Accident Management Initial Diagnosis23. Letter dated March 6, 1997 from Charles H. Cruse to USNRC "Revision to Emergency ActionLevels Technical Basis Document"24. NEI 99-01 SGIFebruary 2016 193 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: S -System MalfunctionSubcategory: 2 -Loss of DC PowerInitiating Condition: Loss of all vital DC power for> 15 min.EAL:SS2.1 Site Area Emergency< 105 VDC on all 125 VDC buses (11, 12, 21 and 22) for _ 15 min. (Note 4)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time.Mode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericLoss of all DC power compromises ability to monitor and control plant safety functions. Prolongedloss of all DC power will cause core uncovering and loss of Containment integrity when there issignificant decay heat and sensible heat in the reactor system.Fifteen minutes was selected as a threshold to exclude transient or momentary power losses.Escalation to a General Emergency would occur by EALs in Category R and Category F.Plant-SpecificThe 125 VDC vital system is divided into four independent and isolated channels. Each channelconsists of one battery, two battery chargers, one DC bus, multiple DC unit control panels, and twoinverters. Each inverter has an associated vital AC distribution panel board. Power to the DC bus,DC unit control panels, and inverters is supplied by the station batteries and/or the batterychargers. Each battery charger is fully rated and can recharge a discharged battery while at thesame time supplying the steady state power requirements of the system. A reserve 125 VDCsystem for the plant is completely independent and isolated from all four separation groups, yet iscapable of replacing any of the 125 VDC batteries. This system consists of one battery, one batterycharger, and the associated DC switching equipment. Only the battery may be transferred forreplacement duty.The safety-related station batteries have been sized to carry their expected shutdown loadsfollowing a plant trip/LOCA and loss of offsite power or following a station blackout without batteryFebruary 2016 194 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearterminal voltage falling below 105 volts. The loss of the 1A Diesel Generator 125 VDC bus 14 or0C Diesel Generator bus 16 does not constitute an entry condition for this EAL.This EAL is the hot condition equivalent of the cold condition loss of DC powerEAL CU2.1.CCNPP Basis Reference(s):1. UFSAR Section 8.4.3 and Figure 8.92. EOP-0 Post-Trip Immediate Actions3. EOP-2 Loss of Off-Site Power, Section V4. AOP-7J Loss of 120 Volt Vital AC or 125 Volt Vital DC Power5. Technical Specifications Bases 3.8.46. NEI 99-01 SS3February 2016195EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:S -System Malfunction3 -Criticality & RPS FailureInitiating Condition: Inadvertent criticalityEAL:SU3.1 Unusual EventAn UNPLANNED sustained positive startup rate observed on nuclear instrumentationMode Applicability:3 -Hot Standby, 4 -Hot ShutdownBasis:GenericThis EAL addresses inadvertent criticality events. While the primary concern of this EAL iscriticality This EAL addresses inadvertent criticality events. This EAL indicates a potentialdegradation of the level of safety of the plant, warranting a UE classification. This EAL excludesinadvertent criticalities that occur during planned reactivity changes associated with reactorstartups (e.g., criticality earlier than estimated).Escalation would be by EALs in Category F, as appropriate to the operating mode at the time ofthe event.Plant-SpecificThe term "sustained" is used to allow exclusion of expected short-term positive startup rates fromplanned fuel bundle or control rod movements during core alteration. These short-term positivestartup rates are the result of the rise in neutron population due to subcritical multiplication.Definitions:UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.CCNPP Basis Reference(s):1. UFSAR Section 7.5.22. 1C05-ALM Reactivity Control Alarm Manual, Window D-05, D-153. AOP-1A Inadvertent Boron Dilution4. NEI 99-01 SU8February 2016196EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategoary:S -System Malfunction3 -Criticality & RPS FailureInitiating Condition: Automatic trip failed to shut down the reactor and the manualactions taken from the reactor control console are successful inshutting down the reactorEAL:SA3.1 AlertAn automatic reactor trip failed to shut down the reactorANDManual actions taken at the Control Room panels successfully shut down the reactor asindicated by reactor power < 5%Mode Applicability:1 -Power OperationBasis:Generic-The reactor should be considered shutdown when it producing less heat than the maximum decayheat load for which the safety systems are designed (5% power).Manual trip actions taken at the Control Room panels are any set of actions by the reactoroperator(s) which causes or should cause control rods to be rapidly inserted into the core andshuts down the reactor.This condition indicates failure of the automatic protection system to trip the reactor. This conditionis more than a potential degradation of a safety system in that a front line automatic protectionsystem did not function in response to a plant transient. Thus the plant safety has beencompromised because design limits of the fuel may have been exceeded. An Alert is indicatedbecause conditions may exist that lead to potential loss of fuel clad barrier or RCS barrier andbecause of the failure of the Reactor Protection System to automatically shut down the plant.If manual actions taken at the reactor control console fail to shut down the reactor, the event wouldescalate to a Site Area Emergency.Plant-SpecificFollowing a successful reactor trip, nuclear power promptly drops to about six percent of theoriginal power level and then decays to a level some 8 decades less at a startup rate (SUR) ofabout (-)1/3 DPM. The reactor power drop continues until reactor power reaches the point at whichthe influence of source neutrons on reactor power starts to be observable. A predictable post-tripFebruary 2016197EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearresponse from an automatic reactor trip signal should therefore consist of a prompt drop in reactorpower as sensed by the nuclear instrumentation (NI) and a negative SUR as nuclear power dropsinto the source range.The RPS setpoints listed in Figure S-i should result in an automatic reactor trip:Figure S-I Automatic RPS TripsREACTOR TRIPHigh Power Level 2/4 VariableHigh Rate-of-Change of Power 2/4 below 15% Pwr 2.6 decade/mmn.Low Reactor Coolant Flow 2/4 above 10-4% Pwr VariableLow Steam Generator Pressure 2/4 670 psi9Low Steam Generator Water Level 2/4 10 in. below top of feed ringHigh Pressurizer Pressure 2/4 2385 psigThermal Margin/Low Pressure 2/4 above 10-4% Pwr VariableLoss of Load 2/4 above 15% Pwr N/AHigh Containment Pressure 2/4 4 psi9Axial Flux Offset 2/4 VariableThermal Margin/SG Press. Duff. Hi 2/4 above 10-4% Pwr 135 psidPer FOP-a, Post-Trip Immediate Actions, the operator ensures that the reactor has tripped bydepressing one set of Manual Reactor Trip buttons immediately following any symptoms of areactor trip. The symptoms include:* Reactor Trip alarm* Control Element Assembly (CEA) Circuit Breaker(s) Trip alarms* Rapid Lowering in Reactor Power* Protection Channel Trip alarm* Reactor Protective System (RPS) Trip Bistable Lights litFollowing depression of the reactor trip buttons, the operator verifies that reactor power isdecreasing. If these responses cannot be verified, as part of contingency actions, the operator isinstructed to open the motor generator (MG) set feeder breakers that provide power to the ControlElement Drive Mechanism (CEDM).If reactor power is above 5%, the reactor is producing more heat than the Auxiliary Feedwatersystem and Atmospheric Dump Valves are designed to remove (ref. 6, 7, 8). The Alert emergencyclassification is required whenever the Shift Manager determines that a required automatic reactortrip did not succeed in reducing reactor power to 5% or lower. It is recognized that EOP-O instructsthe operator to depress the manual trip buttons whether or not a required automatic reactor tripactually occurred. However, the failure of the RPS to complete a reactor trip that reduced reactorFebruary 2016 198 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclearpower to 5% or lower following receipt of an automatic trip signal meets the Alert classificationthreshold of potential substantial degradation in the level of safety of the plant. This is true even ifno radiation alarms indicate fuel problems.In the event that the operator identifies a reactor trip is imminent and successfully initiates amanual reactor trip before the automatic trip setpoint is reached, no declaration is required. Thesuccessful manual trip of the reactor before it reaches its automatic trip setpoint or reactor tripsignals caused by instrumentation channel failures do not lead to a potential fission product barrierloss. If manual reactor trip actions at the Control Room panels (following an unsuccessfulautomatic reactor trip) fail to reduce reactor power to or below 5%, the event escalates to the SiteArea Emergency under EAL SS3.1.CCNPP Basis Reference(s):1. Technical Specifications 3.3.1, Reactor Protective System (RPS) Instrumentation -Operating2. Technical Specifications 3.3.2, Reactor Protective System (RPS) Instrumentation -Shutdown3. Technical Specifications 3.3.3, Reactor Protective System (RPS) Logic and Trip Initiation4. EOP-O Post-Trip Immediate Actions5. UFSAR Section 76. AOP-3G Malfunction of Main Feedwater System7. UFSAR 14.1.2.2.e8. UFSAR 14.4.1 & Table 14.1-29. NEI 99-01 SA2February 2016199EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:S -System Malfunction3 -Criticality & RPS FailureInitiating Condition: Automatic trip and manual actions taken from the reactor controlconsole failed to shut down the reactorEAL:SS3.1 Site Area EmergencyAn automatic reactor trip failed to shut down the reactor as indicated by reactor power >5%ANDManual actions taken at the Control Room panels do not shut down the reactor asindicated by reactor power > 5%Mode Applicability:1 -Power OperationBasis:GenericUnder these conditions, the reactor is producing more heat than the maximum decay heat load forwhich the safety systems are designed and efforts to bring the reactor subcritical are unsuccessful.A Site Area Emergency is warranted because conditions exist that lead to imminent loss orpotential loss of both fuel clad and RCS.The reactor should be considered shutdown when it producing less heat than the maximum decayheat load for which the safety systems are designed (5% power).Manual scram (trip) actions taken at the Control Room panels are any set of actions by the reactoroperator(s) at which causes or should cause control rods to be rapidly inserted into the core andshuts down the reactor.Manual trip actions are not considered successful if action away from the Control Room panels isrequired to trip the reactor. This EAL is still applicable even if actions taken away from the ControlRoom panels are successful in shutting the reactor down because the design limits of the fuel mayhave been exceeded or because of the gross failure of the Reactor Protection System to shutdownthe plant.Escalation of this event to a General Emergency would be due to a prolonged condition leading toan extreme challenge to either core-cooling or heat removal.February 2016200EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearPlant-SpecificFollowing a successful reactor trip, nuclear power promptly drops to about six percent of theoriginal power level and then decays to a level some 8 decades less at a startup rate (SUR) ofabout (-)I/3 DPM. The reactor power drop continues until reactor power reaches the point at whichthe influence of source neutrons on reactor power starts to be observable. A predictable post-tripresponse from an automatic reactor trip signal should therefore consist of a prompt drop in reactorpower as sensed by the nuclear instrumentation (NI) and a negative SUR as nuclear power dropsinto the source range.The RPS setpoints listed in Figure S-I should result in an automatic reactor trip:Figure S-I Automatic RPS TripsREACTOR TRIPHigh Power LevelHigh Rate-of-Change of PowerLow Reactor Coolant FlowLow Steam Generator PressureLow Steam Generator Water LevelHigh Pressurizer PressureThermal Margin/Low PressureLoss of LoadHigh Containment PressureAxial Flux OffsetThermal Margin/SG Press. Duff. Hi2/42/4 below 15% Pwr2/4 above 10-4% Pwr2/42/42/42/4 above 10-4% Pwr2/4 above 15% Pwr2/42/42/4 above 10-4% PwrVariable2.6 decade/min.Variable670 psig10 in. below top of feed ring2385 psigVariableN/A4 psigVariable135 psidPer EOP-0, Post-Trip Immediate Actions, the operator ensures that the reactor has tripped bydepressing one set of Manual Reactor Trip buttons immediately following any symptoms of areactor trip. The symptoms include:* Reactor Trip alarm* Control Element Assembly (CEA) Circuit Breaker(s) Trip alarms* Rapid Lowering in Reactor Power* Protection Channel Trip alarm* Reactor Protective System (RPS) Trip Bistable Lights litFollowing depression of the reactor trip buttons, the operator verifies that reactor power isdecreasing. If these responses cannot be verified, as part of contingency actions, the operator isinstructed to open the motor generator (MG) set feeder breakers that provide power to the ControlElement Drive Mechanism (CEDM).February 2016201EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearIf reactor power is above 5%, the reactor is producing more heat than the Auxiliary Feedwatersystem and Atmospheric Dump Valves are designed to remove (ref. 7, 8, 9). Fast boration is thusrequired and there is an actual major failure of a system intended for protection of the public. Thecombination of failure of both front line and backup protection systems to function in response to aplant transient, along with the continued production of heat poses a direct threat to the Fuel Cladand RCS barriers and warrants declaration of a Site Area Emergency.CCNPP Basis Reference(s):1. Technical Specifications 3.3.1, Reactor Protective System (RPS) Instrumentation -Operating2. Technical Specifications 3.3.2, Reactor Protective System (RPS) Instrumentation -Shutdown3. Technical Specifications 3.3.3, Reactor Protective System (RPS) Logic and Trip Initiation4. EOP-O Post-Trip Immediate Actions5. EOP-8 Functional Recovery6. UFSAR Section 77. AOP-3G Malfunction of Main Feedwater System8. UFSAR 14.1.2.2.e9. UFSAR 14.4.1 & Table 14.1-210. NEI 99-01 SS2February 2016202EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCliffs Annexl:vY-Inn Mi irl,-rCategory:S -System MalfunctionSubcategory: 3 -Criticality & RPS FailureInitiating Condition: Automatic trip and all manual actions fail to shut down the reactorand indication of an extreme challenge to the ability to cool thecore existsEAL:SG3.1 General EmergencyAn automatic reactor trip failed to shut down the reactor as indicated by reactor power >5%ANDAll manual actions fail to shut down the reactor as indicated by reactor power > 5%ANDANY of the following exist or have occurred:* CET readings > 700°F* RCS pressure > PORV setpoint* RCS subcooling < 250FMode Applicability:1 -Power OperationBasis:GenericUnder these conditions, the reactor is producing more heat than the maximum decay heat load forwhich the safety systems are designed and efforts to bring the reactor subcritical are unsuccessful.The reactor should be considered shutdown when it producing less heat than the maximum decayheat load for which the safety systems are designed (5% power). In the event either of thesechallenges exists at a time that the reactor has not been brought below the power associated withthe safety system design a core melt sequence exists. In this situation, core degradation can occurrapidly. For this reason, the General Emergency declaration is intended to be anticipatory of thefission product barrier table declaration to permit maximum off-site intervention time.Plant-SpecificFollowing a successful reactor trip, nuclear power promptly drops to about six percent of theoriginal power level and then decays to a level some 8 decades less at a startup rate (SUR) ofabout (-)1/3 DPM. The reactor power drop continues until reactor power reaches the point at whichFebruary 2016203EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearthe influence of source neutrons on reactor power starts to be observable. A predictable post-tripresponse from an automatic reactor trip signal should therefore consist of a prompt drop in reactorpower as sensed by the nuclear instrumentation (NI) and a negative SUR as nuclear power dropsinto the source range.The RPS setpoints listed in Figure S-i should result in an automatic reactor trip:Figure S-I Automatic RPS TripsREACTOR TRIPHigh Power Level 2/4 VariableHigh Rate-of-Change of Power 2/4 below 15% Pwr 2.6 decade/mai.Low Reactor Coolant Flow 2/4 above 10-4% Pwr VariableLow Steam Generator Pressure 2/4 670 psigLow Steam Generator Water Level 2/4 10 in. below top of feed ringHigh Pressurizer Pressure 2/4 2385 psigThermal Margin/Low Pressure 2/4 above 10-4% Pwr VariableLoss of Load 2/4 above 15% Pwr N/AHigh Containment Pressure 2/4 4 psigAxial Flux Offset 2/4 VariableThermal Margin/SG Press. Diff. Hi 2/4 above 10-4% Pwr 135 psidPer EOP-0, Post-Trip Immediate Actions, the operator ensures that the reactor has tripped bydepressing one set of Manual Reactor Trip buttons immediately following any symptoms of areactor trip. The symptoms include:* Reactor Trip alarm* Control Element Assembly (CEA) Circuit Breaker(s) Trip alarms* Rapid Lowering in Reactor Power* Protection Channel Trip alarm* Reactor Protective System (RPS) Trip Bistable Lights litFollowing depression of the reactor trip buttons, the operator verifies that reactor power isdecreasing. If these responses cannot be verified, as part of contingency actions, the operator isinstructed to open the motor generator (MG) set feeder breakers that provide power to the ControlElement Drive Mechanism (CEDM).If reactor power is above 5%, the reactor is producing more heat than the Auxiliary Feedwatersystem and Atmospheric Dump Valves are designed to remove (ref. 7, 8, 9). Fast boration is thusrequired and there is an actual major failure of a system intended for protection of the public. Thecombination of failure of both front line and backup protection systems to function in response to aFebruary 2016 204 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuc:learplant transient, along with the continued production of heat poses a direct threat to the Fuel Cladand RCS barriers.Core Exit Thermocouples (CETs) are a component of the Inadequate Core CoolingInstrumentation system and provide an indirect indication of fuel clad temperature by measuringthe temperature of the reactor coolant that leaves the core region. The RCS Pressure Safety Limitis 2750 psia per CCNPP Technical Specifications. The saturation temperature for this pressure is682.2°F. Per Action Value Bases Document EOP-24.33, the uncertainty on CET Temperature is+/- 39.8°F. If one or more CETs indicate 722°F (682.2 + 39.8), subcooling has been lost for atleast some locations in the core. CET indications at or above 722°F are a clear sign that core heatremoval capability is lost or greatly reduced and one fission product barrier, the fuel clad, isthreatened due to elevated fuel temperatures. 700°F qualifies as a condition representing apotential loss of the fuel clad barrier (ref. 13).Inability to remove heat from the RCS to the ultimate heat sink (bay or atmosphere) is a loss offunction required for hot shutdown with the reactor at pressure and temperature and thusrepresents potential loss of the Fuel Clad and RCS barriers.The combination of these conditions (reactor power greater than 5% with loss of subcooling marginor inability to remove heat from the RCS) indicates the ultimate heat sink function is under extremechallenge, a core melt sequence may exist and rapid degradation of the fuel clad could begin. Topermit maximum offsite intervention time, the General Emergency declaration is appropriate inanticipation of an inevitable General Emergency declaration due to loss and potential loss of fissionproduct barriers.February 2016 205 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclIearCCNPP Basis Reference(s):1. Technical Specifications 3.3.1, Reactor Protective System (RPS) Instrumentation -Operating2. Technical Specifications 3.3.2, Reactor Protective System (RPS) Instrumentation -Shutdown3. Technical Specifications 3.3.3, Reactor Protective System (RPS) Logic and Trip Initiation4. EOP-O Post-Trip Immediate Actions5. EOP-8 Functional Recovery6. UFSAR Section 77. AOP-3G Malfunction of Main Feedwater System8. UFSAR 14.1.2.2.e9. UFSAR 14.4.1 & Table 14.1-210. ERPIP-800 Core Damage Assessment11. ERPIP-802 Core Damage Assessment Using Core Exit Thermocouples12. EOP-5 Loss of Coolant Accident13. EOP-24.33 Action Value Bases Document14. CEN-152 Emergency Procedure Guidelines15. OP-7 Shutdown Operations15. ERPIP-601 Severe Accident Management Initial Diagnosis16. NEI 99-01 SG2February 2016206EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:S ubcategoary:S -System Malfunction4 -Inability to Reach or Maintain Shutdown ConditionsInitiating Condition: Inability to reach required shutdown within Technical SpecificationlimitsEAL:SU4.1 Unusual EventPlant is not brought to required operating mode within Technical Specifications LCOrequired action completion timeMode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericLimiting Conditions of Operation (LCOs) require the plant to be brought to a required operatingmode when the Technical Specification required configuration cannot be restored. Depending onthe circumstances, this may or may not be an emergency or precursor to a more severe condition.In any case, the initiation of plant shutdown required by the site Technical Specifications requires afour hour report under 10 CFR 50.72 (b) Non-emergency events. The plant is within its safetyenvelope when being shut down within the allowable required action completion time in theTechnical Specifications. An immediate UE is required when the plant is not brought to therequired operating mode within the allowable required action completion time in the TechnicalSpecifications. Declaration of a UE is based on the time at which the LCO-specified required actioncompletion time period elapses under the site Technical Specifications and is not related to howlong a condition may have existed.Plant-SpecificNoneCCNPP Basis Reference(s):1. Technical Specifications 3.0, Limiting Conditions for Operations (LCO) Applicability2. NEI 99-01 SU2February 2016207EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Su bcateg ory:S -System Malfunction5 -InstrumentationInitiating Condition: Unplanned loss of safety system annunciation or indication in theControl Room for >_ 15 min.EAL:SU5.1 Unusual EventUNPLANNED loss of greater than approximately 75% of safety system annunciation orindication on Control Room panels for > 15 mmn. (Note 4)determined that the condition has exceeded, or will likely exceed, the applicable timeMode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericThis EAL is intended to recognize the difficulty associated with monitoring changing plantconditions without the use of a major portion of the annunciation or indication equipment.Recognition of the availability of computer based indication equipment is considered."Planned" loss of annunciators or indicators includes scheduled maintenance and testing activities.Quantification is arbitrary, however, it is estimated that if approximately 75% of the safety systemannunciators or indicators are lost, there is an increased risk that a degraded plant condition couldgo undetected. It is not intended that plant personnel perform a detailed count of theinstrumentation lost but use the value as a judgment threshold for determining the severity of theplant conditions.It is further recognized that plant design provides redundant safety system indication powered fromseparate uninterruptible power supplies. While failure of a large portion of annunciators is morelikely than a failure of a large portion of indications, the concern is included in this EAL due todifficulty associated with assessment of plant conditions. The loss of specific, or several, safetysystem indicators should remain a function of that specific system or component operability status.This will be addressed by the specific Technical Specification. The initiation of a TechnicalSpecification imposed plant shutdown related to the instrument loss will be reported via 10OCER50.72. If the shutdown is not in compliance with the Technical Specification action, the UE is basedon EAL SU4.1.Annunciators or indicators for this EAL include those identified in the Abnormal OperatingProcedures, in the Emergency Operating Procedures, and in other EALs (e.g., area, process,and/or effluent rad monitors, etc.).February 2016208EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearFifteen minutes was selected as a threshold to exclude transient or momentary power losses.This UE will be escalated to an Alert based on a concurrent loss of compensatory indications or if asignificant transient is in progress during the loss of annunciation or indication.Plant-SpecificThe Control Room Panels that house safety related annunciators are listed in the table below:Unit 1 Unit 210C04 20041005 20051 C06 200610C07 2C071008 2C0810C09 20091010 20101013 20131C18A 101901C18B 102010 190 1C20A10C22 1C20B1 C24B 10C2210C26 10C2481033 102610C34 10C3310C34Definitions:UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.February 2016209EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCCNPP Basis Reference(s):1. UFSAR Sections 7.6 and 7.72. AOP-7J Loss of 120 Volt Vital AC or 125 Volt Vital DC Power3. UFSAR 7.5.54. Ol-50A Plant Computer5. OP-AA-103-102, Watch Standing Practices6. NEI 99-01 SU3February 2016210EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:S -System Malfunction5 -InstrumentationInitiating Condition: Unplanned loss of safety system annunciation or indication in theControl Room with either (1) a significant transient in progress, or(2) compensatory indicators are unavailableEAL:SA5.1 AlertUNPLANNED loss of greater than approximately 75% of safety system annunciation orindication on Control Room panels for _> 15 min. (Note 4)AND EITHER:A significant transient is in progress, Table S-2ORCompensatory indications are unavailable (Plant Computer, SPDS)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable timeTable S-2 Significant Transients* Automatic turbine runback > 25% thermal power* Electric load rejection > 25% full electrical load* Reactor trip* Safety Injection actuationMode Applicability:I -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericThis EAL is intended to recognize the difficulty associated with monitoring changing plantconditions without the use of a major portion of the annunciation or indication equipment during asignificant transient."Planned" loss of annunciators or indicators includes scheduled maintenance and testing activities.Quantification is arbitrary, however, it is estimated that if approximately 75% of the safety systemannunciators or indicators are lost, there is an increased risk that a degraded plant condition couldgo undetected. It is not intended that plant personnel perform a detailed count of theinstrumentation lost but use the value as a judgment threshold for determining the severity of theplant conditions. It is also not intended that the Shift Manager be tasked with making a judgmentFebruary 2016211EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nucleardecision as to whether additional personnel are required to provide increased monitoring of systemoperation.It is further recognized that most plant designs provide redundant safety system indication poweredfrom separate uninterruptible power supplies. While failure of a large portion of annunciators ismore likely than a failure of a large portion of indications, the concern is included in this EAL due todifficulty associated with assessment of plant conditions. The loss of specific, or several, safetysystem indicators should remain a function of that specific system or component operability status.This will be addressed by the specific Technical Specification. The initiation of a TechnicalSpecification imposed plant shutdown related to the instrument loss will be reported via 10 CFR50.72. If the shutdown is not in compliance with the Technical Specification action, the UE is basedon EAL SU4.1.Annunciators or indicators for this EAL include those identified in the Abnormal OperatingProcedures, in the Emergency Operating Procedures, and in other EALs (e.g., area, process,and/or effluent rad monitors, etc.)."Compensatory indications" in this context includes computer based information such as PlantProcess Computer and SPDS.Fifteen minutes was selected as a threshold to exclude transient or momentary power losses.This Alert will be escalated to a Site Area Emergency if the operating crew cannot monitor thetransient in progress due to a concurrent loss of compensatory indications with a significanttransient in progress during the loss of annunciation or indication.Plant-SpecificPlant Process Computer and SPDS are considered compensatory indication.Significant transients are listed in Table S-2.The Control Room Panels that house safety related annunciators are listed in the table below:Uniti1 Unit 21 C04 2C041C05 2C051 C06 2C061 C07 2C071 C08 2C081 C09 2C091C10 2C101C13 2C131C18A 1CI9CFebruary 2016212EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclear1018B 10201C019C 1C20A10C22 1C20B10C248 1 C2210C26 10C24810C33 10C2610C34 10C3310C34Definitions:UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.CCNPP Basis Reference(s):1. UFSAR Sections 7.6 and 7.72. AOP-7J Loss of 120 Volt Vital AC or 125 Volt Vital DC Power3. UFSAR 7.5.54. OI-50A Plant Computer5. OP-AA-1 03-102, Watch Standing Practices6. NEI 99-01 SA4February 2016213EP-AA-1 011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:S -System Malfunction5 -InstrumentationInitiating Condition: Inability to monitor a significant transient in progressEAL:SS5.1 Site Area EmergencyLoss of greater than approximately 75% of safety system annunciation or indication onControl Room panels for >_ 15 mai. (Note 4)ANDA significant transient is in progress, Table S-2ANDCompensatory indications are unavailable (Plant Computer, SPDS)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable timeTable S-2 Significant Transients* Automatic turbine runback > 25% thermal power* Electric load rejection > 25% full electrical load* Reactor trip* Safety Injection actuationMode Applicability:I -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericThis EAL is intended to recognize the threat to plant safety associated with the complete loss ofcapability of the Control Room staff to monitor plant response to a significant transient."Planned" and "unplanned" actions are not differentiated since the loss of instrumentation of thismagnitude is of such significance during a transient that the cause of the loss is not anameliorating factor.Quantification is arbitrary, however, it is estimated that if approximately 75% of the safety systemannunciators or indicators are lost, there is an increased risk that a degraded plant condition couldgo undetected. It is not intended that plant personnel perform a detailed count of theinstrumentation lost but use the value as a judgment threshold for determining the severity of theplant conditions. It is also not intended that the Shift Manager be tasked with making a judgmentFebruary 2016214EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nucleardecision as to whether additional personnel are required to provide increased monitoring of systemoperation.It is further recognized that most plant designs provide redundant safety system indication poweredfrom separate uninterruptible power supplies. While failure of a large portion of annunciators ismore likely than a failure of a large portion of indications, the concern is included in this EAL due todifficulty associated with assessment of plant conditions. The loss of specific, or several, safetysystem indicators should remain a function of that specific system or component operability status.This will be addressed by the specific Technical Specification. The initiation of a TechnicalSpecification imposed plant shutdown related to the instrument loss will be reported via 10 CFR50.72. If the shutdown is not in compliance with the Technical Specification action, the NOUE isbased on EAL SU4.1A Site Area Emergency is considered to exist if the Control Room staff cannot monitor safetyfunctions needed for protection of the public while a significant transient is in progress.Annunciators for this EAL are limited to include those identified in the Abnormal OperatingProcedures, in the Emergency Operating Procedures, and in other EALs (e.g. area, process,and/or effluent rad monitors, etc.)Indications needed to monitor safety functions necessary for protection of the public includeControl Room indications, computer generated indications and dedicated annunciation capability."Compensatory indications" in this context includes computer based information such as PlantProcess Computer and SPDS.Fifteen minutes was selected as a threshold to exclude transient or momentary power losses.Plant-SpecificPlant computer and SPDS are considered compensatory indication.Significant transients are listed in Table S-2.The Control RoomPanels that house safety related annunciators are listed in the table below:Unit 1 Unit 21 C04 2C041C05 2C051C06 2C061 C07 2C071C08 2C081C09 2C091C10 2C101C13 2C13February 2016215EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclear1C18A 1C19C1C18B 10201C019C 1C20A1022 1C20B1C24B 102210C26 1 C24B1 C33 10C2610C34 1 C3310C34CCNPP Basis Reference(s):1. UFSAR Sections 7.6 and 7.72. AOP-7J Loss of 120 Volt Vital AC or 125 Volt Vital DC Power3. UFSAR 7.5.54. Ol-50A Plant Computer5. CNG-OP-1 .01-2003 Alarm Response and Control6. NEI 99-01 SS6February 2016216EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:S -System Malfunction6 -CommunicationsInitiating Condition: Loss of all onsite or offsite communications capabilitiesEAL:SU6.1 Unusual EventLoss of all Table S-3 onsite (internal) communication methods affecting the ability toperform routine operationsORLoss of all Table S-3 offsite (external) communication methods affecting the ability toperform offsite notifications to any agencyTable S-3 Communications SystemsOnsite OffsiteSystem (internal) (external)Commercial phone system X XPlant page system XFTS 2001 telephone system XCCNPP Radio System XSatellite Phone System XCellular Phone System X XMode Applicability:I -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericThe purpose of this EAL is to recognize a loss of communications capability that either defeats theplant operations staff ability to perform routine tasks necessary for plant operations or the ability tocommunicate issues with off-site authorities.The loss of off-site communications ability is expected to be significantly more comprehensive thanthe condition addressed by 10 CFR 50.72.February 2016217EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearThe availability of one method of ordinary off-site communications is sufficient to inform federal,state, and local authorities of plant problems. This EAL is intended to be used only whenextraordinary means (e.g., relaying of information from non-routine radio transmissions, individualsbeing sent to off-site locations, etc.) are being used to make communications possible.Plant-SpecificOnsite/offsite communications systems are listed in Table S-3 (ref. 1, 2, 3).This EAL is the hot condition equivalent of the cold condition EAL CU5. 1.CCNPP Basis Reference(s):I. UFSAR Section 7.82. Emergency Response Facility Directory & Communications Equipment Information3. NO-I-I113, Control of Radio Transmitter (PRT)4. NEI 99-01 SU6February 2016218EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnAYIExelon Nuc~lear.............. Im IR ................Category: S -System MalfunctionSubcategory: Fuel Clad DegradationInitiating Condition: Fuel clad degradationEAL:SU7.1 Unusual EventCoolant activity > ANY of the following:* Dose equivalent 1-131 0.5 uCi/gm for 100 hrs. continuous* Dose equivalent 1-131 acceptable region of T.S. Fig. 3.4.15-1* Dose equivalent 1-131 137.5 uCifgm* Gross activity 1 00/E-bar uCi/gmMode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericThis EAL is included because it is a precursor of more serious conditions and, as result, isconsidered to be a potential degradation of the level of safety of the plant.Escalation of this EAL to the Alert level is via the EALs in Category F.This threshold addresses coolant samples exceeding coolant technical specifications limits.Plant-SpecificElevated reactor coolant activity represents a potential degradation in the level of safety of theplant and a potential precursor of more serious problems. This EAL addresses reactor coolantsamples exceeding coolant technical specifications (including allowable transient time limitspermitted in the Technical Specifications). Though the referenced Technical Specification limitsare mode dependent, it is appropriate that the EAL be applicable in modes 1-4, as it indicates apotential degradation in the level of safety of the plant.For mode 4, conditions are not governed by the Technical Specification applicability. While inmode 4 however, any abnormal chemistry sample that is reported will be compared to the criteriaFebruary 2016219EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuc~learof this EAL and an Unusual Event will be declared if met.The maximum value shown on T.S. Figure 3.4. 15-1 is 137.5 uCi/gm dose equivalent 1-131;therefore this value is included in the EAL threshold to address plant conditions below that shownin the T.S. figure. (ref. 1, 2).CCNPP Basis Reference(s):1. Technical Specification 3.4.15 Reactor Coolant System -RCS Specific Activity2. AOP-6A Abnormal Reactor Coolant Chemistry/Activity3. 1(2)C07-ALM F-21 RAD MON LVL HI4. NEI 99-01 SU4February 2016220EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: S -System MalfunctionSubcategory: 7 -Fuel Clad DegradationInitiating Condition: Fuel clad degradationEAL:SU7.2 Unusual EventLetdown Monitor (RY-202-1) high alarm (> 1E+06 cpm)Mode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericThis EAL is included because it is a precursor of more serious conditions and, as result, isconsidered to be a potential degradation of the level of safety of the plant.Escalation of this EAL to the Alert level is via the EALs in Category F.This threshold addresses radiation monitor readings that provide indication of a degradation of fuelclad integrity.Plant-SpecificThis EAL addresses indication of gross failed fuel that may be in excess of Technical Specification(ref. 1) coolant activity limits.The Letdown Radiation Monitor (1 (2)-RY-202-1)) gross radiation channel continuously monitors theactivity in a sample drawn from the RCS and actuates an alarm in the Control Room if apredetermined activity level is reached (ref. 3). The sensor is a gross-gamma plus specific isotope(1-135) monitor; the system is designed to detect activity release from the fuel to the reactor coolantwithin five minutes of the event (ref. 2, 3). The instrument range is 10 -1E+6 cpm. RY-202-1 doesnot read out in pCi/cc (ref. 4).CCNPP Basis Reference(s):1. Technical Specification 3.4.15 Reactor Coolant System -RCS Specific Activity2. AOP-6A Abnormal Reactor Coolant Chemistry/Activity3. 1I(2)C07-ALM F-21 RAD MON LVL HI4. UFSAR Section 9.1.35. NEI 99-01 SU4February 2016 221 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexE~xnlnn NuclerIArCategory:S -System MalfunctionSubcategory: 8 -RCS LeakageInitiating Condition: RCS leakageEAL:SU8.1 Unusual EventUnidentified or pressure boundary leakage > 10 gpm for > 15 min. (Note 4)ORIdentified leakage > 25 gpm for > 15 min. (Note 4)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soonas it is determined that the condition has exceeded, or will likely exceed, the applicable time.Mode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericThis EAL is included as a UE because it may be a precursor of more serious conditions and, asresult, is considered to be a potential degradation of the level of safety of the plant. The 10 gpmvalue for the unidentified or pressure boundary leakage was selected as it is observable withnormal Control Room indications. Lesser values must generally be determined through time-consuming surveillance tests (e.g., mass balances).Relief valve normal operation should be excluded from this EAL. However, a relief valve thatoperates and fails to close per design should be considered applicable to this EAL if the relief valvecannot be isolated.The EAL for identified leakage is set at a higher value due to the lesser significance of identifiedleakage in comparison to unidentified or pressure boundary leakage. In either case, escalation ofthis EAL to the Alert level is via EALs in Category F.Plant-SpecificSTP 0-27-1(2), RCS Leakage Evaluation, provides instructions for calculating primary system leakrate by manual or PC program methods (ref. 2). AOP-2A-I (2), Excessive Reactor CoolantLeakage, provides direction for determining ROS leakage for off normal events and for operationstroubleshooting (ref. 3).February 2016222EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCalvert Cliffs Technical Specifications do not treat Steam Generator tube leakage as RCS pressureboundary leakage. Since Steam Generator tube leakage is identified leakage, the threshold forUnususal Event is > 25 gpm under this initiating condition.CCNPP Basis Reference(s):1. Technical Specifications 3.4.13, Reactor Coolant System Operational Leakage2. AOP-2A Excessive Reactor Coolant Leakage3. STP 0-27-1 (2) RCS Leakage Evaluation4. Technical Specifications 1.1, Definitions5. NEI 99-01 SU5February 2016223EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategiory F -Fission Product Barrier DegqradationEAL Group: Hot Conditions (RCS temperature > 200°F); EALsin this category are applicable only in one or morehot operating modes.EALs in this category represent threats to the defense in depth design concept that precludes therelease of highly radioactive fission products to the environment. This concept relies on multiplephysical barriers any one of which, if maintained intact, precludes the release of significantamounts of radioactive fission products to the environment. The primary fission product barriersare:A. Reactor Fuel Clad (FC): The fuel clad barrier consists of fuel bundle tubes composed ofzirconium-based alloys that contain the fuel pellets.B. Reactor Coolant System (RCS): The RCS Barrier includes the RCS primary side and itsconnections up to and including the pressurizer safety and relief valves, and otherconnections up to and including the primary isolation valves.C. Containment (CNMT): The Containment Barrier includes the Containment building andconnections up to and including the outermost Containment isolation valves. This barrieralso includes the main steam, feedwater, and blowdown line extensions outside theContainment building up to and including the outermost secondary side isolation valve.The EALs in this category require evaluation of the loss and potential loss thresholds listed in thefission product barrier matrix of Table F-I (Attachment 2). "Loss" and "Potential Loss" signify therelative damage and threat of damage to the barrier. "Loss" means the barrier no longer assuresContainment of radioactive materials. "Potential Loss" means integrity of the barrier is threatenedand could be lost if conditions continue to degrade. The number of barriers that are lost orpotentially lost and the following criteria determine the appropriate emergency classification level:Unusual Event:Any loss or any potential loss of ContainmentAlert:Any loss or any potential loss of either Fuel Clad or RCSSite Area Emerqency:Loss or potential loss of any two barriersGeneral Emergqency:Loss of any two barriers and loss or potential loss of the third barrierFebruary 2016 224 EP-AA-I101 Addendum 3(Revision I)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearThe logic used for Category F EALs reflects the following considerations:*The Fuel Clad Barrier and the RCS Barrier are weighted more heavily than theContainment Barrier. UE EALs associated with RCS and Fuel Clad Barriers are addressedunder Category S.*At the Site Area Emergency level, there must be some ability to dynamically assess how farpresent conditions are from the threshold for a General Emergency. For example, if FuelClad and RCS Barrier "Loss" thresholds existed, that, in addition to off-site doseassessments, would require continual assessments of radioactive inventory andContainment integrity. Alternatively, if both Fuel Clad and RCS Barrier "Potential Loss"thresholds existed, the ED would have more assurance that there was no immediate needto escalate to a General Emergency.*The ability to escalate to higher emergency classification levels as an event deterioratesmust be maintained. For example, RCS leakage steadily increasing would represent anincreasing risk to public health and safety.*The Containment Barrier should not be declared lost or potentially lost based on exceedingTechnical Specification action statement criteria, unless there is an event in progressrequiring mitigation by the Containment barrier. When no event is in progress (Loss orPotential Loss of either Fuel Clad and/or RCS) the Containment Barrier status is addressedby Technical Specifications.February 2016225EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCliffs AnnexFxalnn Ne.lr~c~r................... m R ! Category: Fission Product Barrier DegradationSubcategory: N/AInitiating Condition: ANY loss or ANY potential loss of ContainmentEAL:FUI.1 Unusual EventANY loss or ANY potential loss of Containment (Table F-I)Mode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericNonePIa nt-SpecificFuel Clad, RCS and Containment comprise the fission product barriers. Table F-i (Attachment 2)lists the fission product barrier thresholds, bases and references.Fuel Clad and RCS barriers are weighted more heavily than the Containment barrier. Unlike theFuel Clad and RCS barriers, the loss of either of which results in an Alert (EAL FA .1), loss of theContainment barrier in and of itself does not result in the relocation of radioactive materials or thepotential for degradation of core cooling capability. However, loss or potential loss of theContainment barrier in combination with the loss or potential loss of either the Fuel Clad or RCSbarrier results in declaration of a Site Area Emergency under EAL FS1 .1.CCNPP Basis Reference(s):1. NEI 99-01 FU1February 2016226EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory: Fission Product Barrier DegradationSubcategory: N/AInitiating Condition: ANY loss or ANY potential loss of either Fuel Clad or RCSEAL:FAl.1 AlertANY loss or ANY potential loss of either Fuel Clad or RCS (Table F-I)Mode Applicability:I -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericNonePlant-SpecificFuel Clad, RCS and Containment comprise the fission product barriers. Table F-I (Attachment 2)lists the fission product barrier thresholds, bases and references.At the Alert classification level, Fuel Clad and RCS barriers are weighted more heavily than theContainment barrier. Unlike the Containment barrier, loss or potential loss of either the Fuel Clad orRCS barrier may result in the relocation of radioactive materials or degradation of core coolingcapability. Note that the loss or potential loss of Containment barrier in combination with loss orpotential loss of either Fuel Clad or RCS barrier results in declaration of a Site Area Emergencyunder EAL FSI.CCNPP Basis Reference(s):1. NEI 99-01 FA1February 2016227EP-AA-1011 Addendum 3(Revision I)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: Fission Product Barrier DegradationSubcategory: N/AInitiating Condition: Loss or potential loss of ANY two barriersEAL:FSI.1 Site Area EmergencyLoss or potential loss of ANY two barriers (Table F-i)Mode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericNonePlant-SpecificFuel Clad, RCS and Containment comprise the fission product barriers. Table F-I (Attachment 2)lists the fission product barrier thresholds, bases and references.At the Site Area Emergency classification level, each barrier is weighted equally. A Site AreaEmergency is therefore appropriate for any combination of the following conditions:* One barrier loss and a second barrier loss (i.e., loss -loss)* One barrier loss and a second barrier potential loss (i.e., loss -potential loss)* One barrier potential loss and a second barrier potential loss (i.e., potential loss -potentialloss)At the Site Area Emergency classification level, the ability to dynamically assess the proximity ofpresent conditions with respect to the threshold for a General Emergency is important. Forexample, the existence of Fuel Clad and RCS Barrier loss thresholds in addition to offsite doseassessments would require continual assessments of radioactive inventory and Containmentintegrity in anticipation of reaching a General Emergency classification. Alternatively, if both FuelClad and RCS potential loss thresholds existed, the Emergency Director would have greaterassurance that escalation to a General Emergency is less imminent.CCNPP Basis Reference(s):1. NEI 99-01 FSIFebruary 2016 228 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Su bcategory:Initiating Condition:Fission Product Barrier DegradationN/ALoss of ANY two barriers and loss or potential loss of the thirdbarrierEAL:FGI.1 General EmergencyLoss of ANY two barriersANDLoss or potential loss of the third barrier (Table F-I)Mode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericNonePlant-SpecificFuel Clad, RCS and Containment comprise the fission product barriers. Table F-I (Attachment 2)lists the fission product barrier thresholds, bases and references.At the General Emergency classification level each barrier is weighted equally. A GeneralEmergency is therefore appropriate for any combination of the following conditions:* Loss of Fuel Clad, RCS and Containment barriers* Loss of Fuel Clad and RCS barriers with potential loss of Containment barrier* Loss of RCS and Containment barriers with potential loss of Fuel Clad barrier* Loss of Fuel Clad and Containment barriers with potential loss of ROS barrierCCNPP Basis Reference(s):I. NE1 99-01 FG1February 2016229EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearATTACHMENT 2Fission Product Barrier Loss I Potential Loss Matrix and BasisIntroductionTable F-I lists the threshold conditions that define the Loss and Potential Loss of the three fissionproduct barriers (Fuel Clad, Reactor Coolant System, and Containment). The table is structured sothat each of the three barriers occupies adjacent columns. Each fission product barrier column isfurther divided into two columns; one for Loss thresholds and one for Potential Loss thresholds.The first column of the table (to the left of the Fuel Clad Loss column) lists the categories (types) offission product barrier thresholds. The fission product barrier categories are:A. Core Cooling / Heat RemovalB. InventoryC. Radiation / Coolant ActivityD. Isolation StatusE. JudgmentEach category occupies a row in Table F-I thus forming a matrix defined by the category rows andthe Loss/Potential Loss columns. The intersection of each category row with each Loss/PotentialLoss column forms a cell in which one or more fission product barrier thresholds appear. If NEI 99-01 does not define a threshold for a barrier Loss/Potential Loss, the word "None" is entered in thecell.Thresholds are assigned sequential numbers within each Loss and Potential Loss columnbeginning with number one. In this manner, a threshold can be identified by its category title andnumber. For example, the first Fuel Clad barrier Loss in Category A is "FC Loss A.I ," the thirdContainment barrier Potential Loss is "CNMT P-Loss B.3," etc.If a cell in Table F-I contains more than one numbered threshold, each of the numberedthresholds, if exceeded, signifies a Loss or Potential Loss of the barrier. It is not necessary toexceed all of the thresholds in a category before declaring a barrier Loss/Potential Loss.Subdivision of Table F-I by category facilitates association of plant conditions to the applicablefission product barrier Loss and Potential Loss thresholds. This structure promotes a systematicapproach to assessing the classification status of the fission product barriers.When equipped with knowledge of plant conditions related to the fission product barriers, the EAL-user first scans down the category column of Table F-l, locates the likely category and then readsFebruary 2016 230 EP-AA-1011 Addendum 3(Revision I)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclearacross the row of fission product barrier Loss and Potential Loss thresholds in that category todetermine if any threshold has been exceeded. If a threshold has not been exceeded in thatcategory row, the EAL-user proceeds to the next likely category and continues review of the row ofthresholds in the new categoryThe EAL-user must examine each of the three fission product barriers to determine if other barrierthresholds in the category are lost or potentially lost. For example, if Containment radiation issufficiently high (i.e., greater than 14,000 R/hr), a Loss of the Fuel Clad and RCS barriers and aPotential Loss of the Containment barrier exist. Barrier Losses and Potential Losses are thenapplied to the algorithm~s given in EALs FGI.1, FSI.1, FAI.1 and FU1.1 to determine theappropriate emergency classification.In the remainder of this Attachment, the Fuel Clad barrier threshold bases appear first, followed bythe RCS barrier and finally the Containment barrier threshold bases. In each barrier, the bases aregiven according category Loss followed by category Potential Loss beginning with Category A,then B... E.February 2016231EP-AA-1011 Addendum 3(Revision 1)

Calvert Cts AnnexExelon Gonfid*l/ProprietaryExelon N~earTable F-I Fission Product Barrier MatrixFuel Clad Barrier Reactor Coolant System Barrier Containment BarrierCategory Loss Potential Loss Loss Potential Loss Loss Potential Loss1. OTGG flow established1. GET readings > 7000F 2. RCS heat removal cannot be 1. GET readings cannot be restoredestablished < 1,200°F within 15 mai.""2. RGS heat removal cannot be ROS pressure>* PORVCore GTestablished setpoint None 2. GET readings>* 7000FCooling / 1. CTreadings>* 1,2OD°F AND EITHER: None OR ANDHeat RGS pressure > PORV RGS subcooling < 25°FRemoval setpoint Reactor vessel waler level cannotOR be restored > RVLMS 10 in. alarmORGsucoig25F3 Uncontrolled RGS co oldown and to within 15 win.RCS ubcolin < 5°Fleft of Max Operating PressureGurve (EOP Attachment 1, RGSPressure Temperature Limits)1.A Gontainment pressure risefollowed by a rapid unexplaineddrop in Gontainment pressure 3. Gontainment pressure - 50 psigand rising2.Containment pressure or sumplevel response not consistent 4. Gontainment hydrogen1. RGS leak rate>* available with LOGA conditions concentration 4%makeup capacity as indicated bya loss of RGS subcoolingBNone 3. RVLMS level a 10 in. alarm (<25OF)4 RCS leak rate > 50 gpm with 3.RUPTURED SIG (> 50 gpm) is 5. Gontainment pressure >4.25Ivnoyletdown isolated also FAULTED outside of psig AND cannot meet ANY ofGontainment the following conditions:2.RUPTURED SIG results in anEGGSISIA) atuaton 2 Gontainment Spray Pumps4.S(SA) cuainPrimary-to-secondary leakrate Operating*10 gpm

• 3 GA~s OperatingAND

• I Gontainment Spray PumpUnisolable prolonged steam and 2 GA~s Operatingrelease from affected S/G to theenvironment2. Gontainment radiation monitor(5317A1B) reading>*3,500 R/hrCRadiation 3. Post-accident sample dose rate Nonon3tainme) readiaing monR/or NoeNne6 Containment radiation monitor/ Coolant 40 mftem/hr (1 ft from sample) Noe(NoteS/) redn rNn oe(5317YA/B) reading > 14,000 R/hrAtiW 4. Goolant activity >300 p~i/ccDEO 1-1315.Failure of all valves in ANY oneot line to closeIoainNone None None None NoneStatus the environment exists afterGontainment isolation signalS 5. ANY condition in the opinion of 4. ANY condition in the opinion of 4.AYcniini6h pno f 5 N odto nteoiino h .ANY condition in the opinion of 7. ANY condition in the opinion of theEthe Emergency Director that the Emergency Director that the Emergcyndi rectorn th at Emergef .n cy co diretior that oindicafthes the Emergency Director that Emergency Director that indicatesinicte loso h ulca niae oeta oso hul idcthes lossenc irof the G arret Emrec feco tha ind0atb indicates loss of the Gontainment potential loss of the GontainmentJudgment barrieriniae oso h ulca cladin aebarrierPtnalosofheul idcts ssfthRCbrir potential oss f the CS barrier barrier barrierFebruary 2016232EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: Fuel CladCategory: A. Core Cooling/Heat RemovalDegradation Threat: LossThreshold:1. CET readings > 1 ,200°FBasis:GenericThe 1,1200°F reading corresponds to significant superheating of the coolant.Plant-SpecificCore Exit Thermocouples (CETs) are a component of Inadequate Core Cooling Instrumentationand provide an indirect indication of fuel clad temperature by measuring the temperature of thereactor coolant that leaves the core region. The threshold temperature is consistent withAttachment 3 of ERPIP-802, Core Damage Assessment Using Core Exit Thermocouples. Althoughclad rupture due to high temperature is not expected for CET readings less than the threshold,temperatures of this magnitude signal significant superheating of the reactor coolant and coreuncovery. Events that result in CET readings above the loss threshold are classified severeaccidents and lead to a Severe Accident Management Guideline "Badly Damaged (BD)" condition.The BD descriptor signifies possible core overheating to the point clad ballooning/collapse mayhave occurred and portions of the core may melt.CCNPP Basis Reference(s):1. UFSAR7.5.92. ERPIP-600 Severe Accident Management3. ERPIP-601 Severe Accident Management Initial Diagnosis4. ERPIP-802 Core Damage Assessment Using Core Exit Thermocouples5. EOP-5 Loss of Coolant Accident6. EOP-8 Functional Recovery Procedure7. CEN-152 Emergency Procedure GuidelinesFebruary 2016 233 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: Fuel CladCategory: A. Core Cooling/Heat RemovalDegradation Threat: Potential LossThreshold:1. CET readings > 700°FBasis:GenericCET readings > 700°F corresponds to loss of subcooling.Plant-SpecificCore Exit Thermocouples (CETs) are a component of the Inadequate Core CoolingInstrumentation and provide an indirect indication of fuel clad temperature by measuring thetemperature of the reactor coolant that leaves the core region. The RCS Pressure Safety Limit is2750 psia per CCNPP Technical Specifications. The saturation temperature for this pressure is682.2°F. Per Action Value Bases Document EOP-24.33, the uncertainty on CET Temperature is+/- 39.8°F. If one or more CETs indicate 722°F (682.2 + 39.8), subcooling has been lost for atleast some locations in the core. CET indications at or above 7220°F are a clear sign that core heatremoval capability is lost or greatly reduced and one fission product barrier, the fuel clad, isthreatened due to elevated fuel temperatures. 700°F qualifies as a condition representing apotential loss of the fuel clad barrier (ref. 6).CCNPP Basis Reference(s):1. UFSAR 7.5.92. ERPIP-800 Core Damage Assessment3. ERPIP-802 Core Damage Assessment Using Core Exit Thermocouples4. EOP-5 Loss of Coolant Accident5. EOP-8 Functional Recovery Procedure6. EOP-24.33 Actio~n Value Bases Document7. CEN-152 Emergency Procedure GuidelinesFebruary 2016 234 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCulvert Cliffs AnnexExelon Nuclear....................................Barrier:Category:Fuel CladA. Core Cooling/Heat RemovalDegRadhatio Tremoat: PanotbentialaLossheTReShold ue>:OV epon2. RCS heat removal cannot be establishedAND EITHER:RCS pressure> PORV setpointORRCS subcooling <250FBasis:GenericThis subcategory addresses other site specific thresholds that may be included to indicate loss orpotential loss of the Fuel Clad barrier.Plant-SpecificThe steam generators (S/Gs) provide the normal means of heat transfer from the RCS to the maincondenser and ultimate heat sink. EOP-5, Loss of Coolant Accident, requires maintenance of S/Gheat removal at all times during a LOCA, if at all possible. Once RCS pressure and temperatureare reduced, RCS heat removal can be provided by Shutdown Cooling (SDC). Once the SOC isplaced in service, the S/G heat sink capability is no longer necessary.S/Gs are available for RCS heat removal if the level in at least one S/G can be restored andmaintained above -170 in. and TCOLD is not increasing. Core and ROS heat removal is available ifCET readings are less than superheated and the temperature difference between hot legtemperature and cold leg temperature is less than 500F (10°F with forced circulation). If RCSpressure approaches the PORV setpoint (2,400 psia), heat input to the RCS is likely raisingpressure instead of reaching the ultimate heat sink. If RCS subcooling approaches 25°F, themargin to superheated conditions is being reduced. Following an uncomplicated reactor trip,subcooling margin should be in excess of 500F. Subcooling margin greater than 25°F ensures thefluid surrounding the core is sufficiently cooled and provides margin for reestablishing flow shouldFebruary 2016235EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclearsubcooling deteriorate when SI flow is secured. Voids may exist in some parts of the RCS (e.g.,Reactor Vessel head) but are permissible as long as core heat removal is maintained.The combination of these conditions indicates the ultimate heat sink function is under extremechallenge. This threshold addresses loss of functions required for hot shutdown with the reactor atpressure and temperature and thus a potential loss of the Fuel Clad barrier. This is also a potentialloss of the RCS barrier and therefore results in at least a Site Area Emergency.CCNPP Basis Reference(s):1. UFSAR Section 7.5.92. OP-7 Shutdown Operations3. ERPIP-601 Severe Accident Management Initial Diagnosis4. ERPIP-800 Core Damage Assessment5. ERPIP 802 Core Damage Assessment Using Core Exit Thermocouples6. EOP-5 Loss of Coolant Accident7. EOP-8 Functional Recovery Procedure8. EOP-23.02 Subcooling Margin (SCM): 25 Deg F Subcooled9. CEN-152 Emergency Procedure GuidelinesFebruary 2016236EP-AA-1011 Addendum 3(Revision 1I)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexBarrier: Fuel CladCategory: B. InventoryDegradation Threat: LossThreshold:Exelon NuclearNoneFebruary 2016237EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: Fuel CladCategory: B. InventoryDegradation Threat: Potential LossThreshold:3. RVLMS < 10 in. alarmBasis:GenericThere is no Loss threshold associated with this item.The site specific value for the Potential Loss threshold corresponds to the top of the active fuel.Plant-SpecificThe Reactor Vessel Level Monitoring System (RVLMS) is based on the CE Heated JunctionThermocouple (HJTC) system. The HJTC system measures reactor coolant liquid inventory withdiscrete HJTC sensors located at different levels within a separator tube ranging from the fuelalignment plate (i.e., near top of active fuel) to the top of the Reactor Vessel head. The basicprinciple of system operation is detection of a temperature difference between heated andunheated thermocouples.Reactor Vessel water level below the top of the core may lead to a Severe Accident ManagementGuideline "Badly Damaged (BD)" condition. The BD descriptor signifies possible core overheatingto the point of clad ballooning/collapse and melting. When Reactor Vessel/RCS water level dropsto 32.9 ft el., core uncovery is about to occur. The closest RVLMS indication is the 10 in. alarm.This signals inadequate coolant inventory, loss of subcooling and the occurrence of possible fuelclad damage.CCNPP Basis Reference(s):1. UFSAR7.5.92. ERPIP-800 Core Damage Assessment3. OP-7 Shutdown Operations4. ERPIP-600 Severe Accident Management5. ERPIP-601 Severe Accident Management Initial DiagnosisFebruary 2016 238 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:Category:Fuel CladC. Radiation / Coolant ActivityDegradation Threat: LossThreshold:2. Containment radiation monitor (5317A/B) reading > 3,500 R/hrBasis:GenericThe 3,500 R/hr Containment radiation monitor reading is a value which indicates the release ofreactor coolant, with elevated activity indicative of fuel damage, into the Containment.Reactor coolant concentrations of this magnitude are several times larger than the maximumconcentrations (including iodine spiking) allowed within technical specifications and are thereforeindicative of fuel damage.This value is higher than that specified for RCS barrier Loss threshold #3. Thus, this thresholdindicates a loss of both the Fuel Clad barrier and RCS barrier that appropriately escalates theemergency classification level to a Site Area Emergency.There is no Potential Loss threshold associated with this item.Plant-SpecificContainment radiation is indicated on 1 (2)-RI-5317 A&B.CCNPP Basis Reference(s):1. ERPIP-801 Core Damage Assessment Using Containment Radiation Dose RatesFebruary 2016239EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:Category:Fuel CladC. Radiation / Coolant ActivityDegradation Threat: LossThreshold:3. Post-accident sapedose rate > 40 mRem/hr (1ft from samleBasis:GenericThe post accident sample dose rate value corresponds to 300 #.Ci/gm 1-131 equivalent.Assessment by the EAL Task Force indicates that this amount of coolant activity is well above thatexpected for iodine spikes and corresponds to less than 5% fuel clad damage. This amount ofradioactivity indicates significant clad damage and thus the Fuel Clad Barrier is considered lost.There is no Potential Loss threshold associated with this item.Plant-SpecificA shielded 12.5 ml pressurized bomb sample would read 40 mRem/hr at one foot from the sample(168 mRem/hr unshielded) for 5% fuel clad damage. When reactor coolant activity reaches thislevel, significant clad heating has occurred and thus the Fuel Clad barrier is considered lost (ref. 1).CCNPP Basis Reference(s):1. BG&E Fuel Degradation EALs Calculation Worksheet, JSB Associates, February 18, 1993February 2016240EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:Fuel CladCategory:C. Radiation / Coolant ActivityDegrooadtactionThet: LosspccDQ -34. Coolant activity> 300 pCi/cc DEQ 1-131Basis:GenericThe site specific value corresponds to 300 pCi/cc 1-131 equivalent. Assessment by the EAL TaskForce indicates that this amount of coolant activity is well above that expected for iodine spikesand corresponds to less than 5% fuel clad damage. This amount of radioactivity indicatessignificant clad damage and thus the Fuel Clad Barrier is considered lost.There is no Potential Loss threshold associated with this item.Plant-SpecificNoneCCNPP Basis Reference(s):1. NEI 99-01 Revision 5, pg 35February 2016241EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexBarrier: Fuel CladCategory: C. Radiation I Coolant ActivityDegradation Threat: Potential LossThreshold:Exelon NuclearNoneFebruary 2016242EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier: Fuel CladCategory: D. Isolation StatusDegradation Threat: LossThreshold:NoneFebruary 2016243EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexS Barrier: Fuel CladCategory: D. Isolation StatusDegradation Threat: Potential LossThreshold:Exelon NuclearNoneFebruary 2016244EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:Fuel CladCategory:Degradation Threat:E. JudgmentLossThreshold:Basis:GenericThis threshold addresses any other factors that are to be used by the Emergency Director indetermining whether the Fuel Clad barrier is lost. In addition, the inability to monitor the barriershould also be incorporated in this threshold as a factor in Emergency Director judgment that thebarrier may be considered lost.Plant-SpecificThe Emergency Director judgment threshold addresses any other factors relevant to determining ifthe Fuel Clad barrier is lost. Such a determination should include imminent barrier degradation,barrier monitoring capability and dominant accident sequences.CCNPP Basis Reference(s):NoneFebruary 2016245EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:Fuel CladCategory:E. JudgmentDegradation Threat: Potential LossThreshold:4. ANY condition in the opinion of the Emergency Director that indicates potential loss ofthe Fuel Clad barrierBasis:GenericThis threshold addresses any other factors that are to be used by the Emergency Director indetermining whether the Fuel Clad barrier is I potentially lost. In addition, the inability to monitor thebarrier should also be incorporated in this threshold as a factor in Emergency Director judgmentthat the barrier may be considered potentially lost.Plant-SpecificThe Emergency Director judgment threshold addresses any other factors relevant to determining ifthe Fuel Clad barrier is potentially lost. Such a determination should include imminent barrierdegradation, barrier monitoring capability and dominant accident sequences.CCNPP Basis Reference(s):NoneFebruary 2016246EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/Proprietary(aln~r4 CllffQ AnnawIFv~lnn hi,v-Il~r5 VliiltV bA¥IVII IIISItSI'IVHIIBarrier:Category:Degradation Threat:Threshold:NoneReactor Coolant SystemA. Core Cooling/Heat RemovalLossFebruary 2016247EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:Category:Reactor Coolant SystemA. Core Cooling/Heat RemovalDegradation Threat: Potential LossThreshold:1. OTCC flow establishedBasis:GenericThis subcategory addresses other site specific thresholds that may be included to indicate loss orpotential loss of the RCS barrier.Plant-SpecificCCNPP is a CE plant with Once Through Core Cooling (OTCC) capability and has a procedurethat intentionally opens the RCS barrier to cool the core when normal means fail. This procedure isemployed when the heat removal function is extremely challenged. Establishment of OTCC flowrepresents a potential loss of the RCS barrier due to PORVs being intentionally maintained open toestablish adequate core heat removal capability.CCNPP Basis Reference(s):1. EOP-3 Loss of All FeedwaterFebruary 2016248EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:Reactor Coolant SystemCategory:A. Core Cooling/Heat RemovalDegradation Threat: Potential LossThreshold:2. RCS heat removal cannot be establishedAND EITHER:RCS pressure > PORV setpointORRCS subcooling < 250 FBasis:GenericThis subcategory addresses other site specific thresholds t'hat may be included to indicate loss orpotential loss of the RCS barrier.Plant-SpecificThe steam generators (S/Gs) provide the normal means of heat transfer from the RCS to the maincondenser and ultimate heat sink. By cooling down the SIGs, heat input to the RCS from thereactor core is reduced. EOP-5, Loss of Coolant Accident, requires maintenance of S/G heatremoval at all times during a LOCA, if at all possible. Once RCS pressure and temperature arereduced, RCS heat removal can be provided by the Shutdown Cooling (SDC). Once the SDC isplaced in service, the S/G heat sink capability is no longer necessary.S/Gs are available for RCS heat removal if the level in at least one S/G can be restored andmaintained above -170 in. and TCOLD is not increasing. Core and RCS heat removal is available ifCET readings are less than superheated and the temperature difference between hot legtemperature and cold leg temperature is less than 50°F (100F with forced circulation). If RCSpressure approaches the PORV setpoint (2400 psia), heat input to the RCS is likely raisingpressure instead of reaching the ultimate heat sink. If RCS subcooling approaches 25°F, themargin to superheated conditions is being reduced. Following an uncomplicated reactor trip,subcooling margin should be in excess of 50°F. Subcooling margin greater than 25°F ensures theFebruary 2016249EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclearfluid surrounding the core is sufficiently cooled and provides margin for reestablishing flow shouldsubcooling deteriorate when SI flow is secured. Voids may exist in some parts of the RCS (e.g.,Reactor Vessel head) but are permissible as long as core heat removal is maintained.The combination of these conditions indicates the ultimate heat sink function is under extremechallenge. This threshold addresses loss of functions required for hot shutdown with the reactor atpressure and temperature and thus a potential loss of the RCS barrier. This is also a potential lossof the Fuel Clad barrier and therefore results in at least a Site Area Emergency.CCNPP Basis Reference(s):1. UFSAR Section 7.5.92. OP-7 Shutdown Operations3. ERPIP-601 Severe Accident Management Initial Diagnosis4. ERPIP-800 Core Damage Assessment5. ERPIP 802 Core Damage Assessment Using Core Exit Thermocouples6. EOP-5 Loss of Coolant Accident7. EOP-8 Functional Recovery Procedure8. EOP-23.02 Subcoo1ing Margin (SCM): 25 Deg F Subcooled9. CEN-152 Emergency Procedure GuidelinesFebruary 2016250EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: Reactor Coolant SystemCategory: A. Core Cooling/Heat RemovalDegradation Threat: Potential LossThreshold:3. Uncontrolled RCS cooldown and to left of Max Operating Pressure Curve (EOPAttachment 1, RCS Pressure Temperature Limits)Basis:GenericThis subcategory addresses other site specific thresholds that may be included to indicate loss orpotential loss of the RCS barrier.Plant-Specific"Uncontrolled" means that the RCS cooldown was not the result of deliberate action performed inaccordance with plant procedures and exceeds allowable vessel cooldown limits. Among the EOPsafety functions to be maintained is RCS Pressure Control. Per EOP-4, Excess Steam DemandEvent, the potential exists for pressurized thermal shock from an excessive cooldown rate followedby a repressurization.The Max Operating Pressure Curve and RCS cooldown rate limits are established to prevent theeffects of pressurized thermal shock. The region to the left of the curve is labeled the "Non-Operating Area." Several curves are included in EOP Attachment I based on the combinations ofReactor Coolant Pumps (RCPs) in operation. The combination of the conditions of this potentialloss threshold indicates the RCS barrier is under significant challenge.CCNPP Basis Reference(s):1. EOP-4 Excessive Steam Demand Event2. EOP-Attachments, Attachment I RCS Pressure Temperature Limits3. EOP-Attachments, Attachment 14 RCS Cooldown Data Sheet4. EOP-8 Functional Recovery ProcedureFebruary 2016 251 EP-AA-1O11 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: Reactor Coolant SystemCategory: B. InventoryDegradation Threat: LossThreshold:1. RCS leak rate > available makeup capacity as indicated by a loss of RCS subcooling(< 25°F)Basis:GenericThis threshold addresses conditions where leakage from the RCS is greater than availableinventory control capacity such that a loss of subcooling has occurred. The loss of subcooling isthe fundamental indication that the inventory control systems are inadequate in maintaining RCSpressure and inventory against the mass loss through the leak.Plant-SpecificAOP-2A, Excessive Reactor Coolant Leakage, provides a list of conditions that may be observedwhen excessive RCS leakage occurs and provides appropriate actions to prevent and mitigate theconsequences of RCS leakage. Following an uncomplicated reactor trip, subcooling margin shouldbe in the range of 50°F to 75°F. Subcooling margin greater than or equal to 25°F ensures the fluidsurrounding the core is sufficiently cooled and provides margin for reestablishing flow shouldsubcooling deteriorate when SIS flow is secured. Voids may exist in some parts of the ROS (e.g.,Reactor Vessel head) but are permissible as long as core heat removal is maintained. The loss ofsubcooling is therefore the fundamental indication that the inventory control systems are incapableof counteracting the mass loss through the leak in the RCS.The loss of subcooling as a result of inability to establish RCS heat transfer to the ultimate heatsink is indicative of potential losses of the Fuel Clad and RCS barriers.CCNPP Basis Reference(s):1. EOP-8 Subcooling Margin (SCM): 25 Deg F Subcooled2. AOP-2A Excessive Reactor Coolant Leakage3. EOP-5 Loss of Coolant Accident4. EOP-6 Steam Generator Tube RuptureFebruary 2016 252 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCliffsq lFvAInn Nirnlcurk vlmnnv m Barrier:Reactor Coolant SystemCategory:B. InventoryDegradation Threat: LossThreshold:2. RUPTURED SIG results in an ECCS (SIAS) actuationBasis:GenericThis threshold addresses the full spectrum of Steam Generator (SG) tube rupture events inconjunction with Containment barrier loss thresholds. It addresses ruptured SG(s) for which theleakage is large enough to cause actuation of ECCS (SIAS). This is consistent to the RCS leakrate barrier potential loss threshold.By itself, this threshold will result in the declaration of an Alert. However, if the SG is also faulted(i.e., two barriers failed), the declaration escalates to a Site Area Emergency per Containmentbarrier loss thresholds.There is no potential loss threshold associated with this item.Plant-SpecificDefinitions:RupturedIn a steam generator, existence of primary-to-secondary leakage of a magnitude sufficient torequire or cause a reactor trip and safety injection.CCNPP Basis Reference(s):1. EOP-5 Loss of Coolant Accident EOP-5 Loss of Coolant Accident2. EOP-6 Steam Generator Tube Rupture3. 1C08-ALM ESFAS 11, G-054. Technical Specifications Table 3.3.4-1February 2016253EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: Reactor Coolant SystemCategory: B. InventoryDegradation Threat: Potential LossThreshold:4. RCS leak rate > 50 gpm with letdown isolatedBasis:GenericThis threshold is based on the apparent inability to maintain normal liquid inventory within theReactor Coolant System (RCS) by normal operation of the Chemical and Volume Control Systemwhich is considered to be the flow rate equivalent to one charging pump discharging to thecharging header. Isolating letdown is a standard abnormal operating procedure action and mayprevent unnecessary classifications when a non-RCS leakage path such as a CVCS leak exists.The intent of this condition is met if attempts to isolate Letdown are NOT successful. Additionalcharging pumps being required is indicative of a substantial RCS leak.Plant-SpecificThe CVCS includes three positive displacement horizontal pumps with a capacity of 44 gpm each.The pressurizer level control program regulates letdown purification subsystem flow by adjustingthe letdown flow control valve so that the reactor coolant pump (RCP) controlled leak-off plus theletdown flow matches the input from the operating charging pump. Equilibrium pressurizer levelconditions may be disturbed due to RCS temperature changes, power changes, or RCS inventoryloss due to leakage. A decrease in pressurizer water level below the programmed level results in acontrol signal to start one or both standby charging pumps to restore water level. The need for asecond or third charging pump to makeup leakage in excess of letdown flow would be indicative ofsubstantial RCS leakage. The single charging pump capacity is rounded up to 50 gpm for thisthreshold and clearly signals that operation of more than one charging pump is needed.CCNPP Basis Reference(s):1. UFSAR Section 9.1.3February 2016 254 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: Reactor Coolant SystemCategory: C. Radiation / Coolant ActivityDegradation Threat: LossThreshold:3. Containment radiation monitor (5317A/B) reading > 6 R/hr (Note 8)Note 8: High temperature in Containment may induce a current error in the Mineral Insulated (Ml) cable runningthrough Containment to the meter. The CHRRM 1 (2)-Rl-531 7 A&B may not detect this value (6 R/hr) underthese conditions. When Containment temperature reaches 300°F, the meter will indicate approximately 40R/hr for a few minutes then drop to approximately 10 R/hr after three hours. This information is to provideguidance on determining the validity of the readings under the specified high temperature conditions.Basis:GenericThe site specific reading is a value which indicates the release of reactor coolant to theContainment.This reading is less than that specified for Fuel Clad barrier threshold 2. Thus, this threshold wouldbe indicative of a RCS leak only. If the radiation monitor reading increased to that specified by FuelClad barrier threshold, fuel damage would also be indicated.There is no Potential Loss threshold associated with this item.Plant-SpecificThe specified reading is based assuming the instantaneous release and dispersal of the reactorcoolant noble gas and iodine inventory associated with normal operating concentrations (i.e.,within Technical Specifications) into the Containment atmosphere. Because of the very high fuelclad integrity, only small amounts of noble gases would be dissolved in the reactor coolant. Thereading is less than that specified for Fuel Clad barrier Loss #2 because no damage to the fuelclad is assumed. Only leakage from the RCS is assumed for this barrier loss threshold.It is important to recognize that the radiation monitor may be sensitive to shine from the ReactorVessel or RCS piping. Containment radiation is indicated on 1 (2)-RI-531 7 A&B. TypicalContainment radiation readings at full power are 1 to 1 .2 R/hr. The Containment radiation monitorsalarm at 6 R/hr and so is operationally significant.Additionally, high temperatures in Containment may induce a current error in the Mineral Insulated(MI) cable running through Containment to the meter. The CHRRM may not detect this value (6February 2016 255 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearR/hr) under these conditions. CCNPP replaced the original cable with an improved Ml cable underESi199602293 to reduce the induced error to a minimum. When Containment temperature reaches300 degrees F, the meter will indicate approximately 40 R/hr for a few minutes then drop toapproximately 10 R/hr after three hours. This information is to provide guidance on determining thevalidity of the readings under the specified high temperature conditions. This information has beenadded as a note.CCNPP Basis Reference(s):1. ERPIP-801 Core Damage Assessment Using Containment Radiation Dose RatesFebruary 2016256EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexBarrier: Reactor Coolant SystemCategory: C. Radiation I Coolant ActivityDegradation Threat: Potential LossThreshold:Exelon NuclearNoneFebruary 2016257EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvedt Cliffs AnnexExelon NuclearBarrier: Reactor Coolant SystemCategory: D. Isolation StatusDegradation Threat: LossThreshold:NoneFebruary 2016258EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexBarrier: Reactor Coolant SystemCategory: D. Isolation StatusDegradation Threat: Potential LossThreshold:Exelon NuclearNoneFebruary 2016259EP-AA-1O11 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryAnnmrIPvnlnn Mnura-a~rBarrier:Reactor Coolant SystemCategory:E. JudgmentDegradation Threat: LossThreshold:Basis:GenericThis threshold addresses any other factors that are to be used by the Emergency Director indetermining whether the RCS barrier is lost. In addition, the inability to monitor the barrier shouldalso be incorporated in this threshold as a factor in Emergency Director judgment that the barriermay be considered lost.Plant-SpecificThe Emergency Director judgment threshold addresses any other factors relevant to determining ifthe RCS barrier is lost. Such a determination should include imminent barrier degradation, barriermonitoring capability and dominant accident sequences.CCNPP Basis Reference(s):NoneFebruary 2016260EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nurlea~r....... m ...............Barrier:Category:Reactor Coolant SystemE. JudgmentDegradation Threat: Potential LossThreshold:5. ANY condition in the opinion of the Emergency Director that indicates potential loss ofthe RCS barrierBasis:GenericThis threshold addresses any other factors that are to be used by the Emergency Director indetermining whether the RCS barrier is potentially lost. In addition, the inability to monitor thebarrier should also be incorporated in this threshold as a factor in Emergency Director judgmentthat the barrier may be considered potentially lost.Plant-SpecificThe Emergency Director judgment threshold addresses any other factors relevant to determining ifthe RCS barrier is potentially lost. Such a determination should include imminent barrierdegradation, barrier monitoring capability and dominant accident sequences.CCNPP Basis Reference(s):NoneFebruary 2016261EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexBarrier: ContainmentCategory: A. Core Cooling I Heat RemovalDegradation Threat: LossThreshold:Exelon NuclearNoneFebruary 2016262EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: ContainmentCategory: A. Core Cooling / Heat RemovalDegradation Threat: Potential LossThreshold:1. cET rednscannot be restored < 1 ,200°F within 15 min.Basis:GenericThere is no Loss threshold associated with this item.The conditions in this threshold represents an imminent core melt sequence which, if not corrected,could lead to vessel failure and an increased potential for Containment failure. In conjunction withthe Core Cooling and RCS Leakage criteria in the Fuel Clad and RCS barrier columns, thisthreshold would result in the declaration of a General Emergency -- loss of two barriers and thepotential loss of a third. If the function restoration procedures are ineffective, there is no "success"path.The function restoration procedures are those emergency operating procedures that address therecovery of the core cooling critical safety functions. The procedure is considered effective if thetemperature is decreasing or if the vessel water level is increasing.Whether or not the procedures will be effective should be apparent within 15 minutes. TheEmergency Director should make the declaration as soon as it is determined that the procedureshave been, or will be ineffective.Plant-SpecificThis threshold indicates significant core exit superheating and core uncovery. If Core ExitThermocouple (CET) readings are greater than 1 200°F, Fuel Clad barrier is lost. CETs are acomponent of the Inadequate Core Cooling Instrumentation system and provide an indirectindication of fuel clad temperature by measuring the temperature of the reactor coolant that leavesthe core region. The threshold temperature is consistent with Attachment 3 of ERPIP-802, CoreDamage Assessment Using Core Exit Thermocouples. Although clad rupture due to hightemperature is not expected for CET readings less than the threshold, temperatures of thismagnitude signal significant superheating of the reactor coolant and core uncovery. Events thatresult in CET readings above the loss threshold are classified severe accidents and lead to aSevere Accident Management Guideline "Badly Damaged (BD)" condition. The BD descriptorFebruary 2016 263 EP-AA-1 011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExnlnn NucleAar...................... B ...............signifies possible core overheating to the point that clad ballooning/collapse may occur andportions of the core may have melted.It must also be assumed the loss of RCS inventory is a result of a loss of the RCS barrier. Theseconditions, if not mitigated, can lead to core melt which in turn may result in a loss of Containment.Severe accident analyses (e. g., NUREG-1150) have concluded that function restorationprocedures can arrest core degradation within the Reactor Vessel in a significant fraction of thecore damage scenarios, and the likelihood of Containment failure is very small in these events.Given this, it is appropriate to provide a reasonable period to allow function restoration proceduresto arrest the core melt sequence. The phrase "cannot be restored <" infers CET readings haveexceeded the threshold temperature and procedural guidance used to restore RCS inventory hasbeen attempted but is thus far unsuccessful. Whether or not guidance is effective should beapparent within fifteen minutes. The ED should make the declaration as soon as it is determinedthe guidance has not been or will not be effective in restoring temperature below the threshold.CCNPP Basis Reference(s):ERPI P-600 Severe Accident ManagementERPIP-601 Severe Accident Management Initial DiagnosisERPIP-802 Core Damage Assessment Using Core Exit Thermocouples1.2.03February 2016264EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexI-xelnn NIclIA~r...................... m m Barrier: ContainmentDegradation Threat: Potential LossCategory:Threshold:A. Core Cooling / Heat Removal2. CET readings > 700°FANDReactor vessel water level cannot be restored > RVLMS 10 in. alarm within 15 mmn.Basis:GenericThere is no Loss threshold associated with this item.The conditions in this threshold represents an imminent core melt sequence which, if not corrected,could lead to vessel failure and an increased potential for Containment failure. In conjunction withthe Core Cooling and RCS Leakage criteria in the Fuel Clad and RCS barrier columns, thisthreshold would result in the declaration of a General Emergency -- loss of two barriers and thepotential loss of a third. If the function restoration procedures are ineffective, there is no "success"path.The function restoration procedures are those emergency operating procedures that address therecovery of the core cooling critical safety functions. The procedure is considered effective if thetemperature is decreasing or if the vessel water level is increasing.Whether or not the procedures will be effective should be apparent within 15 minutes. TheEmergency Director should make the declaration as soon as it is determined that the procedureshave been, or will be ineffective.Plant-SpecificThis threshold indicates loss of inventory control resulting in significant core exit superheating. TheReactor Vessel Level Monitoring System (RVLMS) can provide indication of potential coreuncovery when level decreases to 10 in. alarm. RVLMS is based on the CE Heated JunctionThermocouple (HJTC) system. The HJTC system measures reactor coolant liquid inventory withdiscrete HJTC sensors located at different levels within a separator tube ranging from the fuelalignment plate (i.e., near top of active fuel) to the Reactor Vessel head. The basic principle ofsystem operation is detection of a temperature difference between heated and unheatedthermocouples. Reactor Vessel water level below the top of the core may lead to a SevereFebruary 2016265EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearAccident Management Guideline "Badly Damaged (BD)" condition. The BD descriptor signifiespossible core overheating to the point that clad ballooning/collapse may occur and portions of thecore may have melted. Reactor Vessel water level at the 10 in. alarm signals inadequate coolantinventory, loss of subcooling and the occurrence of possible fuel clad damage.Core Exit Thermocouples (CETs) are a component of the Inadequate Core CoolingInstrumentation and provide an indirect indication of fuel clad temperature by measuring thetemperature of the reactor coolant that leaves the core region. The RCS Pressure Safety Limit is2750 psia per CCNPP Technical Specifications. The saturation temperature for this pressure is682.2°F. Per Action Value Bases Document EOP-24.33, the uncertainty on CET Temperature is+/- 39.8°F. If one or more CETs indicate 722°F (682.2 + 39.8), subcooling has been lost for atleast some locations in the core. CET indications at or above 722°F are a clear sign that core heatremoval capability is lost or greatly reduced and one fission product barrier, the fuel clad, isthreatened due to elevated fuel temperatures. 700°F qualifies as a condition representing apotential loss of the fuel clad barrier (ref. 4).It must be assumed the loss of RCS inventory is a result of a loss of the ROS barrier. Theseconditions, if not mitigated, likely lead to core melt which in turn may result in a loss ofContainment. Severe accident analyses (e. g., NUREG-1 150) have concluded that functionrestoration procedures can arrest core degradation within the Reactor Vessel in a significantfraction of the core damage scenarios, and that the likelihood of Containment failure is very smallin these events. Given this, it is appropriate to provide a reasonable period to allow functionrestoration procedures to arrest the core melt sequence. The phrase "cannot be restored >" inferscore uncovery has begun and procedural guidance used to restore RCS inventory has beenattempted but is thus far unsuccessful. Whether or not guidance is effective should be apparentwithin fifteen minutes. The ED should make the declaration as soon as it is determined that theguidance has not been or will not be effective in restoring vessel water level above the threshold.CCNPP Basis Reference(s):1. ERPIP-600 Severe Accident Management2. ERPIP-802 Core Damage Assessment Using Core Exit Thermocouples3. CEN-152 Emergency Procedure Guidelines4. EOP-24.33 Action Value Bases DocumentFebruary 2016 266 EP-AA-1 011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:Category:Degradation Threat:ContainmentB. InventoryLossThreshold:Basis:GenericRapid unexplained loss of pressure (i.e., not attributable to Containment spray or condensationeffects) following an initial pressure increase from a primary or secondary high energy line breakindicates a loss of Containment integrity. Containment pressure should increase as a result ofmass and energy release into Containment from a LOCA. Thus, pressure not increasing indicatesContainment bypass and a loss of Containment integrity.This indicator relies on operator recognition of an unexpected response for the condition andtherefore does not have a specific value associated with it. The unexpected response is importantbecause it is the indicator for a Containment bypass condition.Plant-SpecificUFSAR Section 14.20 describes Containment pressure response for a bounding LOCA.CCNPP Basis Reference(s):1. UFSAR Section 14.20February 2016267EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:ContainmentB. InventoryCategory:Degradation Threat: LossThreshold:2. Containment pressure or sump level response not consistent with LOCA conditionsBasis:GenericContainment sump levels should increase as a result of mass and energy release intoContainment from a LOCA. Thus, sump level not increasing indicates Containment bypass and aloss of Containment integrity.This indicator relies on operator recognition of an unexpected response for the condition andtherefore does not have a specific value associated with it. The unexpected response is importantbecause it is the indicator for a Containment bypass condition.Plant-SpecificThe Containment pressure and temperature response and Containment sump water temperatureresponse versus time are given in UFSAR Figures 6.2.1-1 through 6.2.1-6b for the most severeLOCAs. During the LOCA injection mode of ECCS operation, Containment sump and RWST levelsare monitored to ensure switch-over from injection to cold leg recirculation is initiated automaticallyand completed via timely operator action.CCNPP Basis Reference(s):1. UFSAR Figures 6.2.1-1 through 6.2.1-6bFebruary 2016268EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclear...................... m ...............Barrier:ContainmentB. InventoryCategory:Degradation Threat: LossThreshold:3. RUPTURED S/G is also FAULTED outside of ContainmentBasis:GenericThe loss threshold recognizes that SG tube leakage can represent a bypass of the Containmentbarrier as well as a loss of the RCS barrier.Users should realize that this threshold and Containment loss B.4 could be considered redundant.This was recognized during the development process. The inclusion of a threshold that usesEmergency Procedure commonly used terms like "ruptured and faulted" adds to the ease of theclassification process and has been included based on this human factor concern.This threshold results in a UE for smaller breaks that; (1) do not exceed the normal chargingcapacity threshold in RCS leak rate barrier Potential Loss threshold, or (2) do not result in ECCSactuation in RCS SG tube rupture barrier Loss threshold. For larger breaks, RCS barrier thresholdcriteria would result in an Alert. For SG tube ruptures which may involve multiple steam generatorsor unisolable secondary line breaks, this threshold would exist in conjunction with RCS barrierthresholds and would result in a Site Area Emergency. Escalation to General Emergency would bebased on "Potential Loss" of the Fuel Clad Barrier.This threshold addresses the condition in which a ruptured steam generator is also faulted. Thiscondition represents a bypass of the RCS and Containment barriers and is a subset of theContainment loss B.4. In conjunction with RCS leak rate barrier loss threshold, this would alwaysresult in the declaration of a Site Area Emergency.Plant-SpecificA faulted S/G means the existence of secondary side leakage that results in an uncontrolleddecrease in steam generator pressure or the steam generator being completely depressurized. Aruptured S/G means the existence of primary-to-secondary leakage of a magnitude sufficient torequire or cause a reactor trip and safety injection.February 2016269EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryC~I~u~r* (~IifF~ AnnoyI'volrn Mm uIl~rVlIIIV nIIIIVA I...A11i;lVII Definitions:FaultedIn a steam generator, the existence of secondary side leakage that results in an uncontrolleddrop in steam generator pressure or the steam generator being completely depressurized.RupturedIn a steam generator, existence of primary-to-secondary leakage of a magnitude sufficient torequire or cause a reactor trip and safety injection.CCNPP Basis Reference(s):1. EOP-6 Steam Generator Tube Rupture2. EOP-8 Functional Recovery ProcedureFebruary 2016270EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryAnnrnrI=Y~Ilnn hiJa-Il~rk VllalV

• Barrier:ContainmentB. InventoryCategory:Degradation Threat: LossThreshold:4. Primary-to-secondary leakrate > 10 gpmANDUnisolable or prolonged steam release from affected SIG to the environmentBasis:GenericThe loss threshold recognizes that SG tube leakage can represent a bypass of the Containmentbarrier as well as a loss of the RCS barrier.Users should realize that the this loss threshold and Containment loss B.3 could be consideredredundant. This was recognized during the development process. The inclusion of an thresholdthat uses Emergency Procedure commonly used terms like "ruptured and faulted" adds to the easeof the classification process and has been included based on this human factor concern.This threshold results in a UE for smaller breaks that; (1) do not exceed the normal chargingcapacity threshold in RCS leak rate barrier Potential Loss threshold, or (2) do not result in ECCSactuation in RCS SG tube rupture barrier Loss threshold. For larger breaks, RCS barrier thresholdcriteria would result in an Alert. For SG tube ruptures which may involve multiple steam generatorsor unisolable secondary line breaks, this threshold would exist in conjunction with RCS barrierthresholds and would result in a Site Area Emergency. Escalation to General Emergency would bebased on "Potential Loss" of the Fuel Clad Barrier.This threshold addresses SG tube leaks that exceed 10 gpm in conjunction with an unisolablerelease path to the environment from the affected steam generator. The threshold for establishingthe unisolable secondary side release is intended to be a prolonged release of radioactivity fromthe ruptured steam generator directly to the environment. This could be expected to occur whenthe main condenser is unavailable to accept the contaminated steam (i.e., SG tube rupture withconcurrent loss of off-site power and the ruptured steam generator is required for plant cooldownor a stuck open relief valve). If the main condenser is available, there may be releases via airejectors, gland seal exhausters, and other similar controlled, and often monitored, pathways.These pathways do not meet the intent of an unisolable release path to the environment. Theseminor releases are assessed using EALs in Category R.February 2016271EP-AA-101 1 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearPlant-SpecificCool downs conducted to allow controlled isolation of the affected SIG per emergency proceduresare not considered prolonged releases. The criterion for prolonged release is met if the objectiveof EOP-6 or EOP-8 to isolate the affected SIG cannot be met.Definitions:UnisolableA breach or leak that cannot be promptly isolated.CCNPP Basis Reference(s):1. EOP-6 Steam Generator Tube Rupture2. EOP-8 Functional Recovery ProcedureFebruary 2016272EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:Category:ContainmentB. InventoryThresoldimn: rssr 0pigadrsn3. Containment pressure 50 psig and risingBasis:GenericThe site specific pressure is based on the Containment design pressure.Plant-SpecificThis threshold is the Containment design pressure and is in excess of that expected from thedesign basis loss of coolant accident (LOCA). Proper actuation and operation of the Containmentspray system when required should maintain Containment pressure well below the designpressure. The pressure-time responses for the spectrum of LOCAs considered in the plant designbasis are described in Section 14 of the UFSAR. The threshold is therefore indicative of a loss ofboth RCS and Fuel Clad barriers in that it should not be reached without severe core degradation(metal-water reaction) or failure to scram in combination with RCS breach. This condition would beexpected to require the declaration of a General Emergency.CCNPP Basis Reference(s):1. UFSARI1.2.52. UFSAR5.1.13. UFSAR 14.20February 2016273EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: ContainmentCategory: B. InventoryDegradation Threat: Potential LossThreshold:4. Containment hydrogen concentration >4%Basis:GenericExistence of an explosive mixture means a hydrogen and oxygen concentration of at least thelower deflagration limit curve exists. The indications of potential loss under this EAL corresponds tosome of those leading to Containment potential loss threshold A.1.Plant-SpecificAfter a LOCA, the Containment atmosphere is a homogeneous mixture of steam, air, solid andgaseous fission products, hydrogen, and water droplets containing boron and sodium hydroxide.During and following a LOCA, the hydrogen concentration in the Containment results fromradiolytic decomposition of water, metal-water reaction, and aluminum/zinc reaction with the spraysolution. If hydrogen concentration reaches or exceeds the lower flammability limit (4%) in anoxygen rich environment, a potentially explosive mixture exists. If the combustible mixture ignitesinside Containment, loss of the Containment barrier could occur. To generate such levels ofcombustible gas, loss of the Fuel Clad and RCS barriers must also have occurred. Since thisthreshold is also indicative of loss of both Fuel Clad and RCS barriers with the potential loss of theContainment barrier, it therefore will likely warrant declaration of a General Emergency.CCNPP Basis Reference(s):1. UFSAR7.5.82. Technical Specifications Table 3.3.10-13. OI-41A Hydrogen Recombiners4. 1C10-ALM ESFAS 14 Alarm Manual, J-095. ERPIP-803 Core Damage Assessment Using Hydrogen6. EOP-8 Functional Recovery ProcedureFebruary 2016 274 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: ContainmentCategory: B. InventoryDegradation Threat: Potential LossThreshold:5. Containment pressure > 4.25 psig AND cannot meet ANY of the following conditions:* 2 Containment Spray Pumps Operating* 3 CACs Operating* 1 Containment Spray Pump and 2 CACs OperatingBasis:GenericThis threshold represents a potential loss of Containment in that the Containment heatremoval/depressurization system (e.g., Containment sprays, CACs, etc., but not includingContainment venting strategies) are either lost or performing in a degraded manner, as indicatedby Containment pressure greater than the setpoint at which the equipment was supposed to haveactuated.Plant-SpecificTwo Containment Spray Pumps, three Containment air cooling units or the combination of oneContainment spray pump and two Containment air cooling units is defined to be one full train ofdepressurization equipment. This equipment provides 100% of the required cooling capacity duringpost-accident conditions. Each Containment spray system consists of a spray pump, spray header,nozzles, valves, piping, instruments, and controls to ensure an operable flow path capable oftaking suction from the RWST upon an actuation signal. Each Containment aircooling unit consistsof cooling coils, accident backdraft damper, accident fan, service water outlet valves, and controlsnecessary to ensure an operable service water flow path. The Containment pressure setpoint (4.25psig) is the pressure at which the equipment should actuate and begin performing its function.CCNPP Basis Reference(s):1. 1 C08-ALM ESFAS 11 Alarm Manual, G-07, ACTUATION SYSTEM CSAS TRIP2. Technical Specifications Table 3.3.4-13. Technical Specifications 3.6.64. EOP-8 Functional Recovery, Appendix 5, CE-3February 2016 275 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexBarrier: ContainmentCategory: C. Radiation I Coolant ActivityDegradation Threat: LossThreshold:Exelon NuclearNoneFebruary 2016276EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: ContainmentCategory: C. Radiation / Coolant ActivityDegradation Threat: Potential LossThreshold:6. Containment radiation monitor (5317A/B) reading > 14,000 R/hrBasis:GenericThere is no Loss threshold associated with this item.The site specific reading is a value which indicates significant fuel damage well in excess of thethresholds associated with both loss of Fuel Clad and loss of RCS barriers. A major release ofradioactivity requiring off-site protective actions from core damage is not possible unless a majorfailure of fuel clad allows radioactive material to be released from the core into the reactor coolant.Regardless of whether Containment is challenged, this amount of activity in Containment, ifreleased, could have such severe consequences that it is prudent to treat this as a potential loss ofContainment, such that a General Emergency declaration is warranted.Plant-SpecificThe Containment radiation monitor reading is a value that indicates significant fuel damage well inexcess of that required for loss of the RCS barrier and the Fuel Clad barrier. NUREG-1228"Source Estimations During Incident Response to Severe Nuclear Power Plant Accidents" statesthat such readings do not exist when the amount of clad damage is less than 20%. A major releaseof radioactivity requiring offsite protective actions from core damage is not possible unless a majorfailure into the reactor coolant has occurred. Regardless of whether the Containment barrier itselfis challenged, this amount of activity in Containment could have severe consequences if released.It is, therefore, prudent to treat this as a potential loss of the Containment barrier. The reading ishigher than that specified for Fuel Clad barrier Loss #3 and RCS barrier Loss #3. Containmentradiation readings at or above the Containment barrier potential loss threshold, therefore, signify aloss of two fission product barriers and potential loss of a third, indicating the need to upgrade theemergency classification to a General Emergency.Containment radiation is indicated on 1(2)-RI-5317 A&B. Typical Containment radiation readings atfull power are 1 to 1.2 R/hr. The Containment radiation monitors alarm at 6 R/hr.February 2016 277 EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCCNPP Basis Reference(s):1. ERPIP-801 Core Damage Assessment Using Containment Radiation Dose RatesFebruary 2016278EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclealrBarrier:ContainmentCategory:D. Isolation StatusDegradation Threat: LossThreshold:5. Failure of all valves in ANY one line to closeANDDirect downstream pathway to the environment exists after Containment isolationsignalBasis:GenericThis threshold addresses incomplete Containment isolation that allows direct release to theenvironment.The use of the modifier "direct" in defining the release path discriminates against release pathsthrough interfacing liquid systems. The existence of an in-line charcoal filter does not make arelease path indirect since the filter is not effective at removing fission product noble gases. Typicalfilters have an efficiency of 95-99% removal of iodine. Given the magnitude of the core inventory ofiodine, significant releases could still occur. In addition, since the fission product release would bedriven by boiling in the reactor vessel, the high humidity in the release stream can be expected torender the filters ineffective in a short period.There is no Potential Loss threshold associated with this item.Plant-SpecificNoneCCNPP Basis Reference(s):1. EOP-8 Functional Recovery ProcedureFebruary 2016279EP-AA-1011 Adden'dum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier: ContainmentCategory: D. Isolation StatusDegradation Threat: Potential LossThreshold:NoneFebruary 2016280EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:ContainmentE. JudgmentCategory:Degradation Threat: LossThreshold:6. ANY condition in the opinion of the Emergency Director that indicates loss of theContainment barrierBasis:GenericThis threshold addresses any other factors that are to be used by the Emergency Director indetermining whether the Containment barrier is lost. In addition, the inability to monitor the barriershould also be incorporated in this threshold as a factor in Emergency Director judgment that thebarrier may be considered lost.The Containment barrier should not be declared lost or potentially lost based on exceedingTechnical Specification action statement criteria, unless there is an event in progress requiringmitigation by the Containment barrier. When no event is in progress (Loss or Potential Loss ofeither Fuel Clad and/or RCS) the Containment barrier status is addressed by TechnicalSpecifications.Plant-SpecificThe Emergency Director judgment threshold addresses any other factors relevant to determining ifthe Containment barrier is lost. Such a determination should include imminent barrier degradation,barrier monitoring capability and dominant accident sequences.CCNPP Basis Reference(s):NoneFebruary 2016281EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:ContainmentE. JudgmentCategory:Degradation Threat: Potential LossThreshold:7. ANY condition in the opinion of the Emergency Director that indicates potential loss ofthe Containment barrierBasis:GenericThis threshold addresses any other factors that are to be used by the Emergency Director indetermining whether the Containment barrier is potentially lost. In addition, the inability to monitorthe barrier should also be incorporated in this threshold as a factor in Emergency Directorjudgment that the barrier may be considered potentially lost.The Containment barrier should not be declared lost or potentially lost based on exceedingTechnical Specification action statement criteria, unless there is an event in progress requiringmitigation by the Containment barrier. When no event is in progress (Loss or Potential Loss ofeither Fuel Clad and/or RCS) the Containment barrier status is addressed by TechnicalSpecifications.Plant-SpecificThe Emergency Director judgment threshold addresses any other factors relevant to determining ifthe Containment barrier is potentially lost. Such a determination should include imminent barrierdegradation, barrier monitoring capability and dominant accident sequences.CCNPP Basis Reference(s):NoneFebruary 2016282EP-AA-1011 Addendum 3(Revision 1)

ATTACHMENT 3EP-AA-1011, Addendum 3, Revision 1, "Calvert Cliffs Nuclear PowerPlant Emergency Action Levels"Emergency Plan AddendumExelon Confidential/Proprietary InformationWithhold Under 10 CFR 2.390 Exelon Confidential/Proprietary~Exelon Generation°EP-AA-1 011, Addendum 3Revision 1CALVERT CLIFFSNUCLEAR POWER PLANTEMERGENCY ACTION LEVELS Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearTable of ContentsSECTION TITLE PAGE1.0 PURPOSE ........................................................................... 102.0 DISCUSSION ........................................................................ 102.1 Background .................................................................. 102.2 Fission Product Barriers..................................................... 112.3 Emergency Classification Based on Fission ProductBarrier Degradation ......................................................... 112.4 EAL Relationship to EOPs and Critical Safety Function Status.......... 122.5 Symptom-Based vs. Event-Based Approach ..... ........................ 122.6 EAL Organization............................................................ 132.7 Technical Bases Information................................................ 152.8 Operating Mode Applicability ............................................... 162.9 Validation of Indications, Reports and Conditions ........................ 172.10 Planned vs. Unplanned Events............................................. 182.11 Classifying Transient Events ........................................... 2.12 Multiple Simultaneous Events and Imminent EAL Thresholds........... 192.13 Emergency Classification Level Downgrading ............................ 1

93.0 REFERENCES

....................................................................... 203.1 Developmental............................................................... 203.2 Implementing ................................................................ 203.3 Commitments................................................................. 204.0 DEFINITIONS........................................................................ 215.0 CCNPP-TO-NEI 99-01 EAL CROSS REFERENCE .............................. 256.0 ATTACHMENTS..................................................................... 296.1 Attachment 1 -Emergency Action Level Technical Bases....................... 30Cate~qory R Abnormal Rad Levels / Rad Effluents ............................. 30RU1.1 ................................................................ 31RU1.2 ................................................................ 36RAI.1 ..................................... '........................... 38RA1.2 ................................................................ 41RSI.1 ................................................................ 43RS1.2 ................................................................ 47RS1.3 ................................................................ 49RGI.1................................................................ 51February 2016 2 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearTable of ContentsSECTION TITLECategqory RCategqory ECategqory CFebruary 2016PAGE(cont'd)RG1.2................................................................ 56RG1.3................................................................ 58RU2.1 ................................................................ 60RU2.2 ................................................................ 63RA2.1 ................................................................ 64RA2.2 ................................................................ 66RA3.1 ................................................................ 68ISFSI/DSC ........................................................... 69EU1.1 ................................................................ 70Cold Shutdown / Refueling System Malfunction.................. 71CUI.1 ................................................................ 73CA1.1 ................................................................ 76CU2.1 ................................................................ 79CU3.1 ................................................................ 81CU3.2 ................................................................ 83CU3.3 ................................................................ 86CA3.1 ................................................................. 88CS3.1 ................................................................ 92CS3.2 ................................................................ 95CS3.3................................................................ 98CG3.1............................................................... 102CG3.2 .............................................................. 106CU4.1 ............................................................... 111CU4.2 ............................................................... 113CA4.1 ............................................................... 115CU5.1 ............................................................... 118CU6.1 ............................................................... 1203EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvedt CliffsAnnexExelon NuclearSECTION TITLECateciory HCategory SFebruary 2016Table of ContentsPAGEHazards and Other Conditions Affecting Plant Safety.......... 121HU1.1 ............................................................... 123HUI.2 ............................................................... 125HUI.3 ............................................................... 126HUI.4............................................................... 128HU1.5............................................................... 130HA1.1 ............................................................... 132HAI.2 ............................................................... 135HAI.3 ............................................................... 138HAI.4 ............................................................... 141HA1.5 ............................................................... 144HAI.6 ............................................................... 146HU2.1 ............................................................... 148HU2.2............................................................... 150HA2.1 ............................................................... 152HU3.1 ............................................................... 155HU3.2 ............................................................... 157HA3.1 ............................................................... 158HU4.1 ............................................................... 160HA4.1 ............................................................... 163HS4.1 ............................................................... 165HG4.1............................................................... 167HG4.2 .............................................................. 169HA5.1 ............................................................... 170HS5.1 ............................................................... 171HU6.1 ............................................................... 173HA6.1 ............................................................... 174HS6.1 ............................................................... 176HG6.1 .............................................................. 178System Malfunction ............................................... 180SUI.1............................................................... 182SAI.1............................................................... 184SSI.1............................................................... 187SGI.1............................................................... 190SS2.1............................................................... 1944EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearTable of ContentsSECTION TITLE PAGESU3.1 ............................................................... 196SA3.1 ............................................................... 197SS3.1 ............................................................... 200SG3.1 ............................................................... 203SU4.1 ............................................................... 207SU5.1 ............................................................... 208SA5.1 ............................................................... 211SS5.1 ............................................................... 214SU6.1 ............................................................... 217SU7.1 ............................................................... 219SU7.2............................................................... 221SU8.1 ............................................................... 222Category F Fission Product Barrier Degradation ............................. 224FUI.1 ............................................................... 226FAI.1 ............................................................... 227FSI.1 ............................................................... 228FGI.1 ............................................................... 2296.2 Attachment 2 -Fission Product Barrier Loss / Potential LossMatrix and Bases................................................................... 230FC Loss A.1........................................................ 233FC Potential Loss A.1 ............................................. 234FC Potential Loss A.2 ............................................. 235FC Potential Loss B.3 ............................................. 238FC Loss C.2........................................................ 239FC Loss C.3........................................................ 240FC Loss C.4........................................................ 241FC Loss E.5........................................................ 245FC Potential Loss E.4 ............................................. 246RCS Potential Loss A.1 ........................................... 248RCS Potential Loss A.2 ........................................... 249RCS Potential Loss A.3 ........................................... 251RCS Loss B.1...................................................... 252RCS Loss B.2...................................................... 253RCS Potential Loss B.4 ........................................... 254RCS Loss C.3...................................................... 255February 2016 5 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearSECTION6.2Table of ContentsTITLE PAGEAttachment 2 (cont'd)RCS Loss E.4...................................................... 260ROS Potential Loss E.5 ........................................... 261CNMT Potential Loss A.1 ......................................... 263CNMT Potential Loss A.2 ......................................... 265CNMT Loss B.1 .................................................... 267CNMT Loss B.2 .................................................... 268CNMT Loss B.3 .................................................... 269CNMT Loss B.4 .................................................... 270CNMT Potential Loss B.3 ............................... ..........273CNMT Potential Loss B.4 ......................................... 274CNMT Potential Loss B.5 ................................. .........275CNMT Potential Loss C.6 ......................................... 277CNMT Loss D.5.................................................... 279CNMT Loss E.6 .................................................... 281CNMT Potential Loss E.7 ......................................... 282February 20166EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearABBEVIATIONS / ACRONYMSAC .................................................................................... Alternating CurrentAPRM..................................................................... Average Power Range MeterATWS............................................................ Anticipated Transient Without ScramCAC............................................................................. Containment Air CoolerCAS............................................................ '.................... Central Alarm StationCCW ........................................................................ Component Cooling WaterCDE........................................................................ Committed Dose EquivalentCE.............................................................................. Combustion EngineeringCET............................................................................. Core exit ThermocoupleCFR ....................................................................... Code of Federal RegulationsCHRRM.................................................. Containment High Range Radiation MonitorCR .......................................................................................... Control RoomCTMT/CNMT ............................................................................... ContainmentCSF.............................................................................. Critical Safety FunctionCSFST............................................................. Critical Safety Function Status TreeDC ......................................................................................... Direct CurrentDEQ ..................................................................................... Dose EquivalentDHR ............................................................................... Decay Heat RemovalDisch ........................................................................................... DischargeDOT...................................................................... Department of TransportationDSC .............................................................................. Dry Shielded CanisterEAL ............................................................................ Emergency Action LevelECCS................................................................ Emergency Core Cooling SystemECL .................................................................... Emergency Classification LevelED ................................................................................... Emergency DirectorEOF..................................................................... Emergency Operations FacilityEOP.................................................................. Emergency Operating ProcedureEPA.................................................................. Environmental Protection AgencyEPG .................................................................. Emergency Procedure GuidelineEPRI.................................................................. Electric Power Research InstituteERG................................................................... Emergency Response GuidelineEPIP ........................................................ Emergency Plan Implementing ProcedureESF ......................................................................... Engineered Safety FeatureESW ......................................................................... Emergency Service WaterFAA .................................................................... Federal Aviation AdministrationFBI ..................................................................... Federal Bureau of InvestigationFEMA ...................................................... Federal Emergency Management AgencyFebruary 2016 7 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearACRONYMS & ABBREVIATIONS (continued)GE ................................................................................... General EmergencyHOO.......................................................... Headquarters (NRC) Operations OfficerHPSI..................................................................... High Pressure Safety InjectionIC ..................................................................................... Initiating ConditionIM .............................................................................. Instrument MaintenanceIPEEE...................... Individual Plant Examination of External Events (Generic Letter 88-20)ISFSI .................................................... Independent Spent Fuel Storage InstallationKeff............................................................. Effective Neutron Multiplication FactorLCO..................................................................... Limiting Condition of OperationLER ..................................................... '......................... Licensee Event ReportLOCA ......................................................................... Loss of Coolant AccidentLPSI...................................................................... Low Pressure Safety InjectionLWR ................................................................................. Light Water ReactorMSIV........................................................................ Main Steam Isolation ValveMSL ..................................................................................... Main Steam LinemR ......................................................................................... milliRoentgenMW ............................................................................................. MegawattMWS..................................................................... Miscellaneous Waste SystemNEI.............................................................................. Nuclear Energy InstituteNESP ......................................................... National Environmental Studies ProjectNPP ................................................................................ Nuclear Power PlantNRC................................................................... Nuclear Regulatory CommissionNSSS................................................................... Nuclear Steam Supply SystemNORAD .............................................. North American Aerospace Defense CommandNUMARC.............................................. Nuclear Management and Resources CouncilOBE........................................................................ Operating Basis EarthquakeOCA............................................................................. Owner Controlled AreaODCM/ODAM ...................................... Off-site Dose Calculation (Assessment) ManualORO ................................................................... Off-site Response OrganizationOTCC...................................................................... Once Through Core CoolingPA ......................................................................................... Protected AreaPAG......................................................................... Protective Action GuidelinePOAH .............................................................................. Point of Adding HeatPORV.................................................................. Pressure Operated Relief ValvePRA/PSA......................... Probabilistic Risk Assessment / Probabilistic Safety Assessment....................................................................... Pressurized Water ReactorPSIG................................................................... Pounds per Square Inch GaugeFebruary 2016 8 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvedt Cliffs Annex Exelon NuclearACRONYMS & ABBREVIATIONS (continued)R................................................................................................ RoentgenROCC........................................................................... Reactor Control ConsoleRCIC ................................................................... Reactor Core Isolation CoolingRCS............................................................................ Reactor Coolant Systemrem ........................................................................... Roentgen Equivalent ManRETS.................................................. Radiological Effluent Technical SpecificationsRFP ...................................................... .......................... Refueling Pool LevelRPS ......................................................................... Reactor Protection SystemRPV ........................................................................... Reactor Pressure VesselRVLIS ......................................................... Reactor Vessel Level Indicating SystemRWCU .......................................................................... Reactor Water CleanupRWST .................................................................... Reactor Water Storage TankSAE................................................................................ Site Area EmergencySBO ..................................................................................... Station BlackoutSCBA............................................................. Self Contained Breathing ApparatusSG ...................................................................................... Steam GeneratorSI ......................................................................................... Safety InjectionSPOS................................................................ Safety Parameter Display SystemSRO ........................................................................... Senior Reactor OperatorSSE ........................................................................ Safe Shutdown EarthquakeSUR ......................................................................................... Startup RateTEDE.................................................................. Total Effective Dose EquivalentTOAF ................................................................................. Top of Active FuelTSC........................................................................... Technical Support CenterUE ......................................................................................... Unusual EventUFSAR.......................................................... Updated Final Safety Analysis ReportWE ............................................................................... Westinghouse ElectricWOG..................................................................... Westinghouse Owners GroupWRNGM .............................................................. Wide Range Noble Gas MonitorFebruary 2016 9EP-AA-1O11 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclear1.0 PURPOSEThis document provides an explanation and rationale for each Emergency Action Level (EAL)included in the EAL Upgrade Project for Calvert Cliffs Nuclear Power Plant (CCNPP). The EALTechnical Bases Document is intended to provide clarification and understanding of how the EALswere developed for CCNPP as well as the intent of each EAL. This document ensures consistentunderstanding of the EAL scheme for decision makers. It should be used to facilitate review ofthe CCNPP EALs and provide historical documentation for future reference. Decision-makersresponsible for implementation of EAL-TB-HOT or EAL-TB-COLD Emergency Action Level Matrix,may use this document as a technical reference in support of EAL interpretation. This informationmay assist the Emergency Director in making classifications, particularly those involving judgmentor multiple events. The basis information shall also be used in training, for explaining eventclassifications to off-site officials, and facilitates regulatory review and approval of theclassification scheme.The expectation is that emergency classifications are to be made as soon as conditions arepresent and recognizable for the classification, but within 15 minutes in all cases of conditionspresent. Use of this document for assistance is not intended to delay the emergency classification.2.0 DISCUSSION2.1 BackgroundEALs are the plant-specific indications, conditions or instrument readings that are utilized toclassify emergency conditions defined in the CCNPP Emergency Plan.In 1992, the NRC endorsed NUMARC/NESP-007 "Methodology for Development of EmergencyAction Levels" as an alternative to NUREG-0654 EAL guidance.NEI 99-01 (NUMARC/NESP-007) Revision 4 was subsequently issued for industry implementation.Enhancements over earlier revisions included:*Consolidating the system malfunction initiating conditions and example emergency actionlevels which address conditions that may be postulated to occur during plant shutdownconditions.February 2016 10 EP:AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclear* Initiating conditions and example emergency action levels that fully address conditions thatmay be postulated to occur at permanently Defueled Stations and Independent Spent FuelStorage Installations (ISFSIs).* Simplifying the fission product barrier EAL threshold for a Site Area Emergency.Subsequently, Revision 5 of NEI 99-01 has been issued which incorporates resolutions tonumerous implementation issues including the NRC EAL FAQs. Using NEI 99-01 Revision 5 Final(February 2008), CCNPP conducted an EAL implementation upgrade project that produced theEALs discussed herein.2.2 Fission Product BarriersMany of the EALs derived from the NEI methodology are fission product barrier based. That is, theconditions that define the EALs are based upon loss or potential loss of one or more of the threefission product barriers. "Loss" and "Potential Loss" signify the relative damage and threat ofdamage to the barrier. "Loss" means the barrier no longer assures Containment of radioactivematerials; "potential loss" infers an increased probability of barrier loss and decreased certainty ofmaintaining the barrier.The primary fission product barriers are:A. Fuel Clad (FC): The fuel clad barrier consists of fuel bundle tubes composed of zirconium-based alloys that contain the fuel pellets.B. Reactor Coolant System (RCS): The RCS Barrier includes the RCS primary side and itsconnections up to and including the pressurizer safety and relief valves, and otherconnections up to and including the primary isolation valves.C. Containment (CNMT): The Containment Barrier includes the Containment building andconnections up to and including the outermost Containment isolation valves. This barrieralso includes the main steam, feedwater, and blowdown line extensions outside theContainment building up to and including the outermost secondary side isolation valve.2.3 Emergency Classification Based on Fission Product Barrier DegradationThe following criteria are the bases for event classification related to fission product barrier loss orpotential loss:Unusual Event:Any loss or any potential loss of ContainmentFebruary 2016 11 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearAlert:Any loss or any potential loss of either Fuel Clad or RCSSite Area Emerqency:Loss or potential loss of any two barriersGeneral Emerqency:Loss of any two barriers and loss or potential loss of third barrier2.4 EAL Relationship to EOPs and Critical Safety Function StatusWhere possible, the EALs have been made consistent with and utilize the conditions defined in theCCNPP Emergency Operating Procedure (EOP) network. While the symptoms that drive operatoractions specified in the EOPs are not indicative of all possible conditions which warrant emergencyclassification, they define the symptoms, independent of initiating events, for which reactor plantsafety and/or fission product barrier integrity are threatened. When these symptoms are clearlyrepresentative of one of the NEI 99-01 Rev. 5 Initiating Conditions, they have been utilized as anEAL. This permits rapid classification of emergency situations based on plant conditions withoutthe need for additional evaluation or event diagnosis. Although some of the EALs presented hereare based on conditions defined in the EOPs, classification of emergencies using these EALs isnot dependent upon EOP entry or execution. The EALs can be utilized independently or inconjunction with the EOPs.2.5 Symptom-Based vs. Event-Based ApproachTo the extent possible, the EALs are symptom-based. That is, the action level threshold is definedby values of key plant operating parameters that identify emergency or potential emergencyconditions. This approach is appropriate because it allows the full scope of variations in the typesof events to be classified as emergencies. However, a purely symptom-based approach is notsufficient to address all events for which emergency classification is appropriate. Particular eventsto which no predetermined symptoms can be ascribed have also been utilized as EALs since theymay be indicative of potentially more serious conditions not yet fully realized.February 2016 12 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclear2.6 EAL OrganizationThe CCNPP EAL scheme includes the following features:*Division of the EAL set into three broad groups:o EALs applicable under all plant operating modes -This group would be reviewed bythe EAL-user any time emergency classification is considered.oEALs applicable only under hot operating modes -This group would only bereviewed by the EAL-user when the plant is in Hot Shutdown, Hot Standby, Startup,or Power Operation mode.oEALs applicable only under cold operating modes -This group would only bereViewed by the EAL-user when the plant is in Cold Shutdown, Refueling orDefueled mode.The purpose of the groups is to avoid review of hot condition EALs when the plant is in acold condition and avoid review of cold condition EALs when the plant is in a hot condition.This approach significantly minimizes the total number of EALs that must be reviewed bythe EAL-user for a given plant condition, reduces EAL-user reading burden and, thereby,speeds identification of the EAL that applies to the emergency.o Within each of the above three groups, assignment of EALs tocategories/subcategories -Category and subcategory titles are selected torepresent conditions that are operationally significant to the EAL-user.Subcategories are used as necessary to further divide the EALs of a category intological sets of possible emergency classification thresholds. The CCNPP EALcategories/subcategories and their relationship to NEI 99-01 Rev. 5 RecognitionCategories are listed below.February 2016 13 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearEAL Groups, Categories and SubcategoriesELGroup/Category EAL SubcategoryAny Operatinp Mode:R -Abnormal Rad Release / Rad Effluent 1 -Offsite Rad Conditions2 -Onsite Rad Conditions & Spent Fuel Events3 -CR/CAS RadH -Hazards and Other Conditions 1 -Natural or Destructive PhenomenaAffecting Plant Safety 2 -Fire or Explosion3 -Hazardous Gas4 -Security5 -Control Room Evacuation6 -JudgmentNoneE -ISFSI/DSCHot Conditions:S -System Malfunction 1 -Loss of AC Power2 -Loss of DC Power3 -Criticality & RPS Failure4 -Inability to Reach or Maintain Shutdown Conditions5 -Instrumentation6 -Communications7 -Fuel Clad Degradation8 -RCS LeakageF -Fission Product Barrier Degradation NoneCold Conditions:C -Cold Shutdown / Refueling System 1 -Loss of AC PowerMalfunction 2 -Loss of DC Power3 -RCS Level4 -RCS Temperature5 -Communications6 -Inadvertent CriticalityFebruary 201614EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearThe primary tool for determining the emergency classification level is the EAL Classification Matrix.The user of the EAL Classification Matrix may (but is not required to) consult the EAL TechnicalBases Document in order to obtain additional information concerning the EALs under classificationconsideration. The user should consult Sections 2.7 and 2.8, and Attachments 1 and 2 of thisdocument for such information.2.7 Technical Bases InformationEAL technical bases are provided in Attachment 1 for each EAL according to EAL group (Any, Hot,Cold), EAL category (R, E, C, H, S and F) and EAL subcategory. A summary explanation of eachcategory and subcategory is given at the beginning of the technical bases discussions of the EALsincluded in the category. For each EAL, the following information is provided:Cateqory Letter & TitleSubcateqory Number & TitleInitiatinq Condition (IC)Site-specific description of the generic IC given in NEI 99-01 Rev. 5.EAL Identifier (enclosed in rectanqle)Each EAL is assigned a unique identifier to support accurate communication of the emergencyclassification to onsite and offsite personnel. Four characters define each EAL identifier:1. First character (letter): Corresponds to the EAL category as described above (R, E, C,H, S or F)2. Second character (letter): The emergency classification (G, S, A or U)G = General EmergencyS = Site Area EmergencyA = AlertU = Unusual Event3. Third character (number): Subcategory number within the given category.Subcategories are sequentially numbered beginning with the number one (1). If acategory does not have a subcategory, this character is assigned the number one (1).4. Fourth character (number): The numerical sequence of the EAL within the EALsubcategory. If the subcategory has only one EAL, it is given the number one (1).classification (enclosed in rectangqle):Unusual Event (U), Alert (A), Site Area Emergency (S) or General Emergency (G)February 2016 15 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearEAL (enclosed in rectanqle)Wording of the EAL as it appears in the EAL Classification Matrix. Note that defined terms arepresented in all uppercase letters within the EAL wording.Mode ApplicabilityOne or more of the following plant operating conditions comprise the mode to which each EALis applicable: 1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot Shutdown, 5 -ColdShutdown, 6 -Refuel, D -Defueled, or All. (See Section 2.8 for operating mode definitions.)Basis:A Generic basis section provides a description of the rationale for the EAL as PrOvided in NEI99-01 Rev. 5. This is followed by a Plant-Specific basis section that provides CCNPP-relevantinformation concerning the EAL. If the EAL wording contains a defined term, the definition ofthe term is included at the end of the plant-specific basis discussion.CCNPP Basis Reference(s):Site-specific source documentation from which the EAL is derived2.8 Operating Mode Applicability (Technical Specifications Table 1.2)IPower OperationsReactor shutdown margin is less than Technical Specification minimum required (kerr >_0.99) and greater than 5% rated thermal power.February 201616EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclear2 StartulpReactor shutdown margin is less than Technical Specification minimum required(keff> 0.99) and less than or equal to 5% rated thermal power.3 Hot StandbyReactor shutdown margin greater than Technical Specification minimum required(keff < 0.99) with coolant temperature (Tavg) greater than or equal to 300°F.4 Hot ShutdownReactor shutdown margin greater than Technical Specification minimum required(keff < 0.99) with coolant temperature (Tavg) less than 300°F and greater than 200°F.5 Cold ShutdownReactor shutdown margin greater than Technical Specification minimum required(keff < 0.99) with coolant temperature (Tavg) less than or equal to 200°F.6 RefuelReactor vessel head is unbolted.D DefueledAll reactor fuel removed from reactor pressure vessel (full core off load during refueling orextended outage).The plant operating mode that exists at the time that the event occurs (prior to any protectivesystem or operator action is initiated in response to the condition) should be compared to the modeapplicability of the EALs. If a lower or higher plant operating mode is reached before theemergency classification is made, the declaration shall be based on the mode that existed at thetime the event occurred.2.9 Validation of Indications, Reports and ConditionsAll emergency classifications shall be based upon valid indications, reports or conditions. Anindication, report, or condition, is considered to be valid when it is verified by (1) an instrumentchannel check, or (2) indications on related or redundant indicators, or (3) by direct observation byplant personnel, such that doubt related to the indicator's operability, the condition's existence, orthe report's accuracy is removed. Implicit in this definition is the need for timely assessment.February 2016 17 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclear2.10 Planned vs. Unplanned EventsPlanned evolutions involve preplanning to address the limitations imposed by the condition, theperformance of required surveillance testing, and the implementation of specific controls prior toknowingly entering the condition in accordance with the specific requirements of the site'sTechnical Specifications. Activities which cause the site to operate beyond that allowed by thesite's Technical Specifications, planned or unplanned, may result in an EAL threshold being met orexceeded. Planned evolutions to test, manipulate, repair, perform maintenance or modifications tosystems and equipment that result in an EAL value being met or exceeded are not subject toclassification and activation requirements as long as the evolution proceeds as planned and iswithin the operational limitations imposed by the specific operating license. However, theseconditions may be subject to the reporting requirements of 10 CFR 50.72.2.11 Classifying Transient EventsFor some events, the condition may be corrected before a declaration has been made. The keyconsideration in this situation is to determine whether or not further plant damage occurred whilethe corrective actions were being taken. In some situations, this can be readily determined, in othersituations, further analyses may be necessary (e.g., coolant radiochemistry following an ATWSevent, plant structural examination following an earthquake, etc.). Classify the event as indicatedand terminate the emergency once assessment shows that there were no consequences from theevent and other termination criteria are met.Existing guidance for classifying transient events addresses the period of time of event recognitionand classification (15 minutes). However, in cases when EAL declaration criteria may be metmomentarily during the normal expected response of the plant, declaration requirements shouldnot be considered to be met when the conditions are a part of the designed plant response, orresult from appropriate Operator actions.There may be cases in which a plant condition that exceeded an EAL was not recognized at thetime of occurrence but is identified well after the condition has occurred (e.g., as a result of routinelog or record review), and the condition no longer exists. In these cases, an emergency should notbe declared. Reporting requirements of 10 CFR 50.72 are applicable and the guidance of NUREG-1022, Event Reporting Guidelines 10 CFR 50.72 and 50.73, should be applied.February 2016 18 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclear2.12 Multiple Simultaneous Events and Imminent EAL ThresholdsWhen multiple simultaneous events occur, the emergency classification level is based on thehighest EAL reached. For example, two Alerts remain in the Alert category. Or, an Alert and a SiteArea Emergency is a Site Area Emergency. Further guidance is provided in RIS 2007-02,Clarification of NRC Guidance for Emergency Notifications During Quickly Changing Events.Since CCNPP is a multi-unit station with shared safety-related system and functions, emergencyclassification level upgrading must also consider the effects of a loss of a common system on morethan one unit (e.g., potential for radioactive release from more than one core). For example, thecontrol panels for both units are in close proximity within the same room. Thus, Control Roomevacuation most likely would affect both units. There are a number of other systems and functionswhich may be shared. This must be considered in the emergency classification level declaration.Although the majority of the EALs provide very specific thresholds, the Emergency Director (ED)must remain alert to events or conditions that lead to the conclusion that exceeding the EALthreshold is imminent. If, in the judgment of the ED, an imminent situation is at hand, theclassification should be made as if the threshold has been exceeded. While this is particularlyprudent at the higher emergency classes (the early classification may permit more effectiveimplementation of protective measures), it is nonetheless applicable to all emergency classes.2.13 Emergency Classification Level DowngradingAnother important aspect of usable EAL guidance is the consideration of what to do when the riskposed by an emergency is clearly decreasing. A combination approach involving recovery fromGeneral Emergencies and some Site Area Emergencies and termination from Unusual Events,Alerts, and certain Site Area Emergencies causing no long term plant damage appears to be thebest choice. Downgrading to lower emergency classification levels adds notifications but may havemerit under certain circumstances.February 2016 19 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclear

3.0 REFERENCES

3.1 Developmental3.1.1 NEI 99-01 Rev. 5 Final, Methodology for Development of Emergency ActionLevels, February 2008, ADAMS Accession Number ML080450 1493.1.2 NRC Regulatory Issue Summary (RIS) 2003-18, Supplement 2, Use of NuclearEnergy Institute (NEI) 99-01, Methodology for Development of Emergency ActionLevels Revision 4, Dated January 2003 (December 12, 2005)3.1.3 RIS 2007-02 Clarification of NRC Guidance for Emergency Notifications DuringQuickly Changing Events3.2 Implementing3.2.13.2.23.2.33.2.4EAL-HOT MatrixEAL-COLD MatrixEAL Comparison MatrixEAL Matrix3.3 CommitmentsNoneFebruary 201620EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclear4.0 DEFINITIONS (ref. 3.1.1 except as noted)Affecting Safe ShutdownEvent in progress has adversely affected functions that are necessary to bring the plant to andmaintain it in the applicable hot or cold shutdown condition. Plant condition applicability isdetermined by Technical Specification LCOs in effect.Example 1: Event causes damage that results in entry into an LCO that requires the plant to beplaced in hot shutdown. Hot shutdown is achievable, but cold shutdown is not. This event is not"affecting safe shutdown."Example 2: Event causes damage that results in entry into an LCO that requires the plant to beplaced in cold shutdown. Hot shutdown is achievable, but cold shutdown is not. This event is"affecting safe shutdown."Airliner/Large AircraftAny size or type of aircraft with the potential for causing significant damage to the plant (refer to theSecurity Plan for a more detailed definition).BombRefers to an explosive device suspected of having sufficient force to damage plant systems orstructures.Civil DisturbanceA group of people violently protesting station operations or activities at the site.Confinement BoundaryThe barrier(s) between areas containing radioactive substances and the environment.Containment ClosureThe site specific procedurally defined actions taken to secure Containment and its associatedstructures, systems, and components as a functional barrier to fission product release underexisting plant conditions. As applied to CCNPP, Containment Closure is the action or condition thatensures Containment and its associated systems, structures or components (SSC), as listed inSTP O-55A, provide a functional barrier to fission product release.ExplosionA rapid, violent, unconfined combustion, or catastrophic failure of pressurized/energized equipmentthat imparts energy of sufficient force to potentially damage permanent structures, systems, orcomponents.ExtortionAn attempt to cause an action at the station by threat of force.FaultedIn a steam generator, the existence of secondary side leakage that results in an uncontrolled dropin steam generator pressure or the steam generator being completely depressurized.February 2016 21 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearFireCombustion characterized by heat and light. Sources of smoke such as slipping drive belts oroverheated electrical equipment do not constitute fires. Observation of flame is preferred but is notrequired if large quantities of smoke and heat are observed.HostageA person(s) held as leverage against the station to ensure that demands will be met by the station.Hostile ActionAn act toward CCNPP or its personnel that includes the use of violent force to destroy equipment,take hostages, and/or intimidate the licensee to achieve an end. This includes attack by air, land,or water using guns, explosives, projectiles, vehicles, or other devices used to deliver destructiveforce. Other acts that satisfy the overall intent may be included.Hostile Action should not be construed to include acts of civil disobedience Or felonious acts thatare not part of a concerted attack on CCNPP. Non-terrorism-based EALs should be used toaddress such activities, (e.g., violent acts between individuals in the owner controlled area).Hostile ForceOne or more individuals who are engaged in a determined assault, overtly or by stealth anddeception, equipped with suitable weapons capable of killing, maiming, or causing destruction.ImminentMitigation actions have been ineffective, additional actions are not expected to be successful, andtrended information indicates that the event or condition will occur. Where imminent timeframes arespecified, they shall apply.IntrusionThe act of entering without authorization. Discovery of a bomb in a specified area is indication ofintrusion into that area by a hostile force.Independent Spent Fuel Storage Installation (ISFSI)A complex that is designed and constructed for the interim storage of spent nuclear fuel and otherradioactive materials associated with spent fuel storage.Normal LevelsAs applied to radiological IC/EALs, the highest reading in the past twenty-four hours excluding thecurrent peak value.Normal Plant OperationsActivities at the plant site associated with routine testing, maintenance, or equipment operations, inaccordance with normal operating or administrative procedures. Entry into abnormal or emergencyoperating procedures, or deviation from normal security or radiological controls posture, is adeparture from Normal Plant Operations.ProjectileAn object directed toward a NPP that could cause concern for its continued operability, reliability,or personnel safety.February 2016 22 EP-AA-1011lAddendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearProtected AreaThe site specific area which normally encompasses all controlled areas within the securityProtected Area fence.RupturedIn a steam generator, existence of primary-to-secondary leakage of a magnitude sufficient torequire or cause a reactor trip and safety injection.SabotageDeliberate damage, mis-alignment, or mis-operation of plant equipment with the intent to renderthe equipment inoperable. Equipment found tampered with or damaged due to malicious mischiefmay not meet the definition of sabotage until this determination is made by security supervision.Safety-Related Structures, Systems or Component (as defined in 10CFR50.2)Those structures, systems and components that are relied upon to remain functional during andfollowing design basis events to assure:(1) The integrity of the reactor coolant pressure boundary;(2) The capability to shut down the reactor and maintain it in a safe shutdown condition;(3) The capability to prevent or mitigate the consequences of accidents which could result inpotential offsite exposures.Security ConditionAny security event as listed in the approved security contingency plan that constitutes athreaticompromise to site security, threat/risk to site personnel, or a potential degradation to thelevel of safety of the plant. A security condition does not involve a hostile action.Strike ActionWork stoppage within the Protected Area by a body of workers to enforce compliance withdemands made on CCNPP. The strike action must threaten to interrupt Normal Plant Operations.UnisolableA breach or leak that cannot be promptly isolated.UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is not theresult of an intended evolution or expected plant response to a transient.ValidAn indication, report, or condition, is considered to be valid when it is verified by (1) an instrumentchannel check, or (2) indications on related or redundant indicators, or (3) by direct observation byplant personnel, such that doubt related to the indicator's operability, the condition's existence, orthe report's accuracy is removed. Implicit in this definition is the need for timely assessment.February 2016 23 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearVisible DamageDamage to equipment or structure that is readily observable without measurements, testing, oranalysis. Damage is sufficient to cause concern regarding the continued operability or reliability ofaffected safety structure, system, or component. Example damage includes: deformation due toheat or impact, denting, penetration, rupture, cracking, paint blistering. Surface blemishes (e.g.,paint chipping, scratches) should not be included.Vital AreaAny areas, normally within the CCNPP Protected Area, that contains equipment, systems,components, or material, the failure, destruction, or release of which could directly or indirectlyendanger the public health and safety by exposure to radiation.February 201624EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclear5.0 CCNPP-TO-NEI 99-01 EAL CROSSREFERENCEThis cross-reference is provided to facilitate association and location of a CCNPP EAL within theNEI 99-01 IC/EAL identification scheme. Further information regarding the development of theCCNPP EALs based on the NEI guidance can be found in the EAL Comparison Matrix.CCNPP NEI 99-01EAL IC ExampleEAL ICEALRU1.1 AU1 1RU1.2 AU1 3RU2.1 AU2 1RU2.2 AU2 2RA1.1 AA1 1RA1.2 AA1 3RA2.1 AA2 2RA2.2 AA2 1RA3.1 AA3 1RS1.1 AS1 1RS1.2 AS1 2RS1.3 AS1 4RG1.1 AG1 1RG1.2 AG1 2RG1.3 AG1 4EUI.1 E-HU1 1CUI.1 CU3 1CU2.1 CU7 1CU3.1 CU1 1CU3.2 CU2 1February 201625EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCCNPP NEI 99-01EAL ICExampleEAL ICEALCU3.3 CU2 2CU4.1 CU4 1CU4.2 CU4 2CU5.1 CU6 1, 2CU6.1 CU8 2CA 1.1 CA3 1CA3.1 CA1 1, 2CA4.1 CA4 1, 2CS3.1 CS1 1CS3.2 0S1 2CS3.3 0S1 3CG3.1 CG1 1CG3.2 CG1 2FU1.1 FU1 1FA1.1 FA1 1FS1.1 FS1 1FG1.1 FGI 1HUI.1 HU1 1HU1.2 HU1 2HU1.3 HU1 '3HU1.4 HU1 4HU1.5 HU1 5HU2.1 HU2 1HU2.2 HU2 2HU3.1 HU3 1February 201626EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCCNPP NEI 99-01EAL ICExampleEAL ICEALHU3.2 HU3 2HU4.1 HU4 1, 2, 3HU6.1 HU5 .1HAl.1 HAl 1HA1.2 HA1 2HA1.3 HA1 3HA1.4 HA1 4HA1.5 HA1 6HA1.6 HA1 5HA2.1 HA2 1HA3.1 HA3 1HA4.1 HA4 1, 2HA5.1 HA5 1HA6.1 HA6 1HS4.i HS4 1HS5.1 HS2 1HS6.1 HS3 1HG4.1 HG1 1HG4.2 HG1 2HG6.1 HG2 ISUl.1 SU1 1SU3.1 SU8 1SU4.1 SU2 1SU5.1 SU3 1SU6.1 SU6 1, 2February 201627EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCCNPP NEI 99-01EAL ICExampleEAL ICEALSU7.1 SU4 2SU7.2 SU4 1SU8.1 SU5 1, 2SA1.1 SA5 1SA3.1 SA2 1SA5.1 SA4 1SS1.1 SS11SS2.1 SS3 1SS3.1 SS21SS5.1 SS6 1SG1.1 SG1 1SG3.1 SG2 1February 201628EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclear6.0 ATTACHMENTS6.1 Attachment 1, Emergency Action Level Technical Bases6.2 Attachment 2, Fission Product Barrier Loss / Potential Loss Matrix and BasisFebruary 201629EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearAttachment 1Category R -Abnormal Rad Levels I Rad EffluentsEAL Group: ANY (EALs in this category are applicable to anyplant condition, hot or cold.)Many EALs are based on actual or potential degradation of fission product barriers because of theelevated potential for offsite radioactivity release. Degradation of fission product barriers though isnot always apparent via non-radiological symptoms. Therefore, direct indication of elevatedradiological effluents or area radiation levels are appropriate symptoms for emergencyclassification.At lower levels, abnormal radioactivity releases may be indicative of a failure of Containmentsystems or precursors to more significant releases. At higher release rates, offsite radiologicalconditions may result which require offsite protective actions. Elevated area radiation levels inplant may also be indicative of the failure of Containment systems or preclude access to plant vitalequipment necessary to ensure plant safety.Events of this category pertain to the following subcategories:1. Offsite Rad ConditionsDirect indication of effluent radiation monitoring systems provides a rapid assessmentmechanism to determine releases in excess of classifiable limits. Projected offsite doses,actual offsite field measurements or measured release rates via sampling indicate doses ordose rates above classifiable limits.2. Onsite Rad Conditions & Spent Fuel EventsSustained general area radiation levels in excess of those indicating loss of control ofradioactive materials or those levels which may preclude access to vital plant areas alsowarrant emergency classification.3. CR/CAS RadSustained general area radiation levels which may preclude access to areas requiringcontinuous occupancy also warrant emergency classification.February 2016 30 EP-AA-1O11 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:Initiating Condition:R -Abnormal Rad Release / Rad Effluent1 -Offsite Rad ConditionsANY release of gaseous or liquid radioactivity to the environmentgreater than 2 times the ODCM for 60 minutes or longerEAL:RUI.1 Unusual EventANY gaseous or liquid monitor reading > Table R-1 column "UE" for _> 60 min. (Note 2)Note 2: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the release duration has exceeded, or will likely exceed, the applicable time. In the absence*of data to the contrary, assume that the release duration has exceeded the applicable time if an ongoingrelease is detected and the release start time is unknown.Table R-1 Effluent Monitor Classification ThresholdsMonitor GE SAE Alert J UEGaseousWRNGM 3.2E+09 IJCi/sec 3.2E+08 pCi/sec 3.2E+07 pCi/sec 3.2E+05 pCi/sec(RIC-541 5)Main Steam Effluent(RIC 5421/5422) 2.99E+04 iiCi/cc 2.99E+03 jiCi/cc 2.99E+i02 p~Ci/cc N/AMain Vent(RI-5415) N/A N/A N/A 2.OE+05 cpmWaste Processing(RI-5410) N/A N/A N/A 4.0E+05 cpmFuel Handling Area Vent(RI-5420) N/A N/A N/A 3.4E+05 cpmLiquid Waste Disch*(RE-2201) N/A N/A N/A 8.4E+05 cpm* with effluent discharge not isolatedMode Applicability:AllBasis:GenericThe Emergency Director should not wait until the applicable time has elapsed, but should declarethe event as soon as it is determined that the condition will likely exceed the applicable time.This EAL addresses a potential decrease in the level of safety of the plant as indicated by aradiological release that exceeds regulatory commitments for an extended period of time.February 201631EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearNuclear power plants incorporate features intended to control the release of radioactive effluents tothe environment. Further, there are administrative controls established to prevent unintentionalreleases, or control and monitor intentional releases. The occurrence of extended, uncontrolledradioactive releases to the environment is indicative of a degradation in these features and/orcontrols.The 2 x 00CM limit multiples are specified only to distinguish between non-emergency conditions.While these multiples obviously correspond to an off-site dose or dose rate, the emphasis inclassifying these events is the degradation in the level of safety of the plant, not the magnitude ofthe associated dose or dose rate.Releases should not be prorated or averaged. For example, a release exceeding 4x ODCM for 30minutes does not meet the threshold.This EAL includes any release for which a radioactivity discharge permit was not prepared, or arelease that exceeds the conditions (e.g., minimum dilution flow, maximum discharge flow, alarmsetpoints, etc.) on the applicable permit.This EAL addresses radioactivity releases, that for whatever reason, cause effluent radiationmonitor readings to exceed the threshold identified in the IC.This EAL is intended for sites that have established effluent monitoring on non-routine releasepathways for which a discharge permit would not normally be prepared.Plant-SpecificThe main plant vents consist of the exhaust flow from the auxiliary building ventilation systems andthe condenser offgas system. Batch releases from the Waste Gas Decay Tanks, Containmentvents and Containment purges are also directed into this stream. Per 00CM Attachment 7, theUnit 1 and Unit 2 vent flow rates are assumed to be 56.3 m3/sec and 42.7 m3/sec, respectively.Each plant vent is monitored by a beta sensitive plastic scintillator Wide Range Noble Gas Monitor(WRNGM 1-RIC-5415 and 2-RIC-5415) which is displayed in pCi/sec and a Geiger-Muller tubeMain Vent Monitor (1-RI-5415 and 2-RI-5415) which is displayed in CPM. The EAL values weredetermined assuming annual average meteorology, RCS noble gas concentrations and doseconversion factors used for emergency preparedness offsite dose assessment. The total gaseousrelease corresponding to 2 times 00CM limits is approximately 0.114 mrem in one hour ascalculated below.1. 2 x 00CM = 2 x 500 mrem/year = 1000 mrem/year2. Hours/year = 24 x 365 = 8760 hour0.101 days <br />2.433 hours <br />0.0145 weeks <br />0.00333 months <br />s/year3. (1000 mrem/year) / (8760 hour0.101 days <br />2.433 hours <br />0.0145 weeks <br />0.00333 months <br />s/year) = 0.114 mrem/hour (or 1.14E-3 mSv/hour)The values for the vent radiation monitor readings are based on 90% of the 2 maximumpermissible concentration (MPC) as discussed in 0DCM 3.11.2.1 at the site boundary. ThisFebruary 2016 32 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclearreduction will account for events that may result in releases through both unit vents. The 10%factor allowance for the other unit vent is conservative because it is two to three orders ofmagnitude larger than the normal releases through each vent. For the main vent monitors, whichread in CPM, the Unit 1 flow rate is assumed because it yields the lowest (most limiting)concentration.RIC-541 5 EAL ThresholdODCM limit corresponds to 1.8 E+5 tJCi/sec (site total)2 x 1.8 E+5 tpCi/sec = 3.6 E+5 pCi/secAssume event in one unit, allow 10% for release from other unitRIC-5415 EAL Threshold =0.9 x 3.6 E+5 pJCi/sec =3.24 E+5 pCi/secRead as 3.2 E+5 tpCi/secMinimum Concentration Corresponding to RI-5415 ReadingConcentration = Release rate (uCi/sec)Flow rate (cc/sec)Unit 10ODCM flow rates = 56.3 m3/secUnit 1 Concentration = 3.24 E+5 uJCi/sec56.3 m3/sec x 106 cc/rn3=5.7 E-3 Unit 20ODCM flow rates = 42.7 m3/secUnit 2 Concentration = 3.24 E+5 uCi/sec42.7 m3/sec x 10~6 cc/rn3=7.6 E-3 i.Ci/ccThe calculated concentration result is converted to CPM so it can be read on RI-5415.February 201633EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearUnit 1 Conc. Unit 2 Conc. Monitor Eff. Unit I Unit 2Isotope RCS Conc. % Total (IpCi/cc) (tpCi/cc) (CPM/10-6) CPM CPMKr-85 0.43 9.62 5.5 E-4 7.3 E-4 35 1.9 E+4 2.6 E+4Kr-85m 0.16 3.58 2.1 E-4 2.7 E-4 55 1.2 E+4 1.5 E+4Kr-87 0.15 3.36 1.9 E-4 2.6 E-4 218 4.1 E+4 5.6 E+4Kr-88 0.28 6.36 3.7 E-4 4.8 E-4 289 1.1 E+5 1.4 E+5Xe-133 2.6 58.17 3.3 E-3 4.4 E-3 1.87 6.2 E+3 8.3 E+3Xe-135 0.85 19.01 1.1 E-3 1.4 E-3 70 7.7 E+4 1.0 E+5Totals 4.47 100.00 5.7 E-3 71!6 E-3 2.7 E+5 3.5 E+5The lower of the Unit 1 and Unit 2 values is conservatively rounded to 2.0E+5 CPM;In a similar manner, values were determined for the Waste Processing Monitor (1-RI-5410 and 2-Rl-5410) assuming noble gas distribution for Waste Gas Decay Tank rupture, average annualmeteorology and a nominal waste processing ventilation flow of 23.4 m3/sec (49,500 CFM). At 2DAC at the site boundary, this corresponds to a reading of 4.0 E+5 CPM.In a similar manner to that shown for RI-5415, values were determined for the Fuel Handling AreaVent Monitor (0-RI-5420) assuming only monitor response to noble gas released from a FuelHandling Incident, average annual meteorology and a nominal fuel handling area ventilation flow of15.1 m3/sec (32,000 CEM). At 2 DAC at the site boundary, per Reference 2 this corresponds to areading of 3.4 E+5 CPM.Analysis was also performed for potential releases through Access Control Point and ECCS Pump(PP) Room. Per Reference 2, 2 DAC at the site boundary corresponds to monitor readings foreach of these locations that are greater than 1 E+6 CPM (i.e., off-scale high). The EGOS PP RoomMonitors (1/2-RI-5406) and the Access Control Monitor (0-RI-5425) are not considered herebecause they will be offscale high at the Unusual Event emergency classification level. Therefore,these monitors provide no useful information for this EAL and are excluded from consideration.Liquid effluent is monitored by the Liquid Waste Discharge Radiation Monitor (0-RE-2201). A highradiation alarm from this monitor results in a signal to close the Liquid Waste Discharge Valves. Ifthese valves do not shut, the operators stop the pump being used for the discharge and shut theLiquid Waste RMS Outlet valve.February 201634EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearThe Steam Generator Blowdown liquid effluent monitor upper range cannot detect releasesassociated with two times the ODCM limits and therefore would be assessed per EAL RU1 .2sample analysis.The designation "N/A" in Table R-1 indicates that the listed instrument range is insufficient toindicate the specified value and therefore no value is used.A radiation monitor reading is valid when a release path is established. If the release path to theenvironment has been isolated, the radiation monitor reading is not valid for classification.CCNPP Basis Reference(s):1. Radioactivity Release Emergency Action Levels, J.B. Mcllvaine, JSB Associates, Inc.,September 19902. Off-Site Dose Calculation Manual (ODCM) for the Calvert Cliffs Nuclear Power Plant3. AOP-6B Accidental Release of Radioactive Liquid Waste4. UFSAR Section 11.1.2.1 Liquid Waste Processing System5. NEI 99-01 AU1February 201635EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:S ubcateg ory:R -Abnormal Rad Release/IRad Effluent1 -Offsite Rad ConditionsInitiating Condition: ANY release of gaseous or liquid radioactivity to the environmentgreater than 2 times the 0DCM for 60 minutes or longerEAL:RUI.2 Unusual EventConfirmed sample analyses for gaseous or liquid releases indicate concentrations orrelease rates > 2 x ODCM limits for > 60 min. (Note 2)Note 2: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the release duration has exceeded, or will likely exceed, the applicable time. In the absenceof data to the contrary, assume that the release duration has exceeded the applicable time if an ongoingrelease is detected and the release start time is unknown.Mode Applicability:AllBasis:GenericThe Emergency Director should not wait until the applicable time has elapsed, but should declarethe event as soon as it is determined that the condition will likely exceed the applicable time.This EAL addresses a potential decrease in the level of safety of the plant as indicated by aradiological release that exceeds regulatory commitments for an extended period of time.Nuclear power plants incorporate features intended to control the release of radioactive effluents tothe environment. Further, there are administrative controls established to prevent unintentionalreleases, or control and monitor intentional releases. The occurrence of extended, uncontrolledradioactive releases to the environment is indicative of a degradation in these features and/orcontrols.The 2 x 00CM limit multiples are specified only to distinguish between non-emergency conditions.While these multiples obviously correspond to an off-site dose or dose rate, the emphasis inclassifying these events is the degradation in the level of safety of the plant, not the magnitude ofthe associated dose or dose rate.Releases should not be prorated or averaged. For example, a release exceeding 4x ODCM for 30minutes does not meet the threshold.This EAL includes any release for which a radioactivity discharge permit was not prepared, or arelease that exceeds the conditions (e.g., minimum dilution flow, maximum discharge flow, alarmsetpoints, etc.) on the applicable permit.February 201636EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearThis EAL addresses uncontrolled releases that are detected by sample analyses, particularly onunmonitored pathways, e.g., spills of radioactive liquids into storm drains, heat exchanger leakagein river water systems, etc.Plant-SpecificReleases in excess of two times the site Offsite Dose Calculation Manual (ODCM) (ref. 1)instantaneous limits that continue for 60 minutes or longer represent an uncontrolled situation andhence, a potential degradation in the level of safety. The final integrated dose (which is very low inthe Unusual Event emergency class) is not the primary concern here; it is the degradation in plantcontrol implied by the fact that the release was not isolated within 60 minutes. Therefore, it is notintended that the release be averaged over 60 minutes. For example, a release of 4 times theODCM limit for 30 minutes does not exceed this initiating condition. Further, the ED should not waituntil 60 minutes has elapsed, but should declare the event as soon as it is determined that therelease duration has or will likely exceed 60 minutes.Sample analyses are "confirmed" when the analytical results have been confirmed by Chemistry.CCNPP Basis Reference(s):1. Off-Site Dose Calcu'lation Manual (ODCM) for the Calvert Cliffs Nuclear Power Plant2. NEI 99-01 AU1February 201637EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:R -Abnormal Rad Release / Rad EffluentSubcategory: 1 -Offsite Rad ConditionsInitiating Condition: ANY release of gaseous or liquid radioactivity to the environmentgreater than 200 times the ODCM for 15 minutes or longerEAL:RA1.1 AlertANY gaseous monitor reading > Table R-1 column "Alert" for -> 15 mai. (Note 2)Note 2: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the release duration has exceeded, or will likely exceed, the applicable time. In the absenceof data to the contrary, assume that the release duration has exceeded the applicable time if an ongoingrelease is detected and the release start time is unknown.[ Table R-1 Effluent Monitor Classification Thresholds[Monitor GE SAE Alert UEGaseousWRNGM 3.2E+09 pCi/sec 3.2E+08 pCi/sec 3.2E+07 IpCi/sec 3.2E+05 pCi/sec(RIC-541 5)Main Steam Effluent 2.99E+04 iiCi/cc 2.99E+03 p.Ci/cc 2.99E+02 p.Ci/cc N/A(RIC-5421/5422)Main Vent N/A N/A N/A 2.0E+05 cpm(RI-541 5)Waste Processing N/A N/A N/A 4.0E+i05 cpm(RI-541 0)Fuel Handling Area Vent N/A N/A N/A 3.4E+05 cpm(RI-5420)Liquid Waste Disch* N/A N/A N/A 8.4E+05 cpm(RE-2201)* with effluent discharge not isolatedMode Applicability: AllBasis:GenericThe Emergency Director should not wait until the applicable time has elapsed, but should declarethe event as soon as it is determined that the condition will likely exceed the applicable time.This EAL addresses an actual or substantial potential decrease in the level of safety of the plant asindicated by a radiological release that exceeds regulatory commitments for an extended period oftime.February 201638EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearNuclear power plants incorporate features intended to control the release of radioactive effluents tothe environment. Further, there are administrative controls established to prevent unintentionalreleases, or control and monitor intentional releases. The occurrence of extended, uncontrolledradioactive releases to the environment is indicative of a degradation in these features and/orcontrols.The 200 x 0DCM limit multiples are specified only to distinguish between non-emergencyconditions. While these multiples obviously correspond to an off-site dose or dose rate, theemphasis in classifying these events is the degradation in the level of safety of the Releasesshould not be prorated or averaged. For example, a release exceeding 600 x ODCM for 5 minutesdoes not meet the threshold.This EAL includes any release for which a radioactivity discharge permit was not prepared, or arelease that exceeds the conditions (e.g., minimum dilution flow, maximum discharge flow, alarmsetpoints, etc.) on the applicable permit.This EAL is intended for sites that have established effluent monitoring on non-routine releasepathways for which a discharge permit would not normally be prepared.Plant-SpecificA description of the applicable monitors and the methods used to calculate EAL values is shown inthe Bases for RU1 .1. Values for this EAL are based on the values shown in RU1 .1 multiplied by100.The ECCS PP Room Monitors (1/2-RI-5406) and the Access Control Monitor (0-RI-5425) are notconsidered here because they will be offscale high at the Unusual Event emergency classificationlevel. At the Alert level, the readings on the main vent monitors (1/2-RI-541 5), the WasteProcessing Vent Monitors (1/2-RI-541 0), and the Fuel Handling Area Vent Monitor (0-RI-5420) arewell above the top of the instrument indicated range (1 .0E+6 CPM). Therefore, these monitorsprovide no useful information for this EAL and are excluded from consideration.The purpose of the Main Steam Effluent Radiation Monitor System is to monitor possible noble gasreleases to the atmosphere from the main steam line through the atmospheric steam dump valves,the main steam safety relief valves, and the auxiliary feedwater steam turbine exhaust. The systemincludes two radiation monitors (1/2-RI-5421 and 1/2-RI-5422) per unit -one radiation monitor foreach steam generator. The noble gas release rate of 3.2E+7 pCi/second (which corresponds to awhole body dose of 10 mrem in one hour at the site boundary) may also occur through release viamain steam safety valve or atmospheric dump valve.February 2016 39 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCiav~rt AnnexlExnlnn Niil~r~IV Vl vlmm IV m ........ Vl i i EP-CALC-00001, Determination of Emergency Action Level Criteria for Calvert Cliffs NuclearPower Plant Main Steam Line Radiation Monitors, outlines, in detail, the calculation andmethodology demonstrated below.RAI .1 Threshold for RIC-5421, RIC-5422RGI.1 Threshold Value = 2.99 E+4 pCi/cc (see section RGI.1)GE Site Boundary Dose Threshold =1000 mremAlert Site Boundary Dose Threshold = 10 mremMain Steam Monitor Reading (pCi/cc) = Alert Site Boundary Dose Threshold X RGI.1 Threshold ValueGB Site Boundary Dose Threshold_10 mrem X29 lic-1000 mnrem X29 tic=2.99 E+2 pCi/ccBased on the March 14, 1993 SG tube rupture event at Palo Verde Unit 2, the main steam effluentmonitors (RI-5421, RI-5422) may read N16 immediately following SG tube rupture and prior toreactor trip. However, given the short half-life of N1 6, this should clear within the first minutefollowing reactor trip.The designation "N/A" in Table R-1 indicates that the listed instrument range is insufficient toindicate the specified value and therefore no value is used.A radiation monitor reading is valid when a release path is established. If the release path to theenvironment has been isolated, the radiation monitor reading is not valid for classification.CCNPP Basis Reference(s):1. Radioactivity Release Emergency Action Levels, J.B. Mcllvaine, JSB Associates, Inc.,September 19902. Off-Site Dose Calculation Manual (ODCM) for the Calvert Cliffs Nuclear Power Plant3. NEI 99-01 AA14. EP-CALC-00001, Determination of Emergency Action Level Criteria for Calvert Cliffs NuclearPower Plant Main Steam Line Radiation MonitorsFebruary 201640EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:S ubcategory:R -Abnormal Rad Release / Rad Effluent1 -Offsite Rad ConditionsInitiating Condition: ANY release of gaseous or liquid radioactivity to the environmentgreater than 200 times the ODCM for 15 minutes or longerEAL:RA1 .2 AlertConfirmed sample analyses for gaseous or liquid releases indicate concentrations orrelease rates > 200 x ODCM limits for > 15 min. (Note 2)Note 2: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the release duration has exceeded, or will likely exceed, the applicable time. In the absenceof data to the contrary, assume that the release duration has exceeded the applicable time if an ongoingrelease is detected and the release start time is unknown.Mode Applicability:AllBasis:GenericThe Emergency Director should not wait until the applicable time has elapsed, but should declarethe event as soon as it is determined that the condition will likely exceed the applicable time.This EAL addresses an actual or substantial potential decrease in the level of safety of the plant asindicated by a radiological release that exceeds regulatory commitments for an extended period oftime.Nuclear power plants incorporate features intended to control the release of radioactive effluents tothe environment. Further, there are administrative controls established to prevent unintentionalreleases, or control and monitor intentional releases. The occurrence of extended, uncontrolledradioactive releases to the environment is indicative of a degradation in these features and/orcontrols.The 200 x ODCM limit are specified only to distinguish between non-emergency conditions. Whilethese multiples obviously correspond to an off-site dose or dose rate, the emphasis in classifyingthese events is the degradation in the level of safety of the plant, not the magnitude of theassociated dose or dose rate.Releases should not be prorated or averaged. For example, a release exceeding 600 x ODCM for5 minutes does not meet the threshold.This EAL includes any release for which a radioactivity discharge permit was not prepared, or arelease that exceeds the conditions (e.g., minimum dilution flow, maximum discharge flow, alarmsetpoints, etc.) on the applicable permit.February 201641EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearThis EAL addresses uncontrolled releases that are detected by sample analyses, particularly onunmonitored pathways, e.g., spills of radioactive liquids into storm drains, heat exchanger leakage.Plant-SpecificConfirmed sample analyses in excess of two hundred times the site Offsite Dose CalculationManual (ODCM) limits that continue for 15 minutes or longer represent an uncontrolled situationand hence, a potential degradation in the level of safety. This event escalates from the UnusualEvent by raising the magnitude of the release by a factor of 100 over the Unusual Event level (i.e.,200 times ODCM). Prorating the 500 mRem/yr basis of the 10 CFR 20 non-occupational MPClimits for both time (8766 hr/yr) and the 200 multiplier, the associated Exclusion Area Boundarydose rate would be approximately 10 mRem/hr. If sample analysis indicates the threshold is metand nothing is done within 15 minutes to effect a release reduction, the ED can conclude that theEAL threshold is met without second sample results.Sample analyses are "confirmed" when the analytical results have been confirmed by Chemistry.CCNPP Basis Reference(s):1. Off-Site Dose Calculation Manual (ODCM) for Calvert Cliffs Nuclear Power Plant2. NEI 99-01 AAIFebruary 201642EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:Initiating Condition:R -Abnormal Rad Release/IRad Effluent1 -Offsite Rad ConditionsOffsite dose resulting from an actual or imminent release ofgaseous radioactivity exceeds 100 mRem TEDE or 500 mRemthyroid CDE for the actual or projected duration of the releaseusing actual meteorologyEAL:RSI .1 Site Area EmergencyANY radiation monitor reading > Table R-1 column "SAE" for _> 15 min. (Note 1)* Do not delay declaration awaiting dose assessment results* If dose assessment results are available, declaration should be based on doseassessment instead of radiation monitor values (see EAL RS1 .2)Note 1: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition will likely exceed the applicable timeTable R-1 Effluent Monitor Classification ThresholdsMonitor GE S AE ,Alert UEGaseousWRNGM 3.2E+09 pCi/sec 3.2E+08 pCi/sec 3.2E+07 pCi/sec 3.2E+05 pCi/sec(RIC-541 5)Main Steam Effluent 2.99E+'04 2.99 E+03 jiCi/cc 2.99 E+O2 jiCi/cc N/A(RlC-5421 /5422)Main Vent N/A N/A N/A 2.0E+05 cpm(RI-541 5)Waste Processing N/A N/A N/A 4.0E+05 cpm(RI-541 0)Fuel Handling Area Vent N/A N/A N/A 3.4E+05 cpm(RI-5420)Liquid Waste Disch* N/A N/A "N/A 8.4E+05 cpm(RE-2201)* with effluent discharge not isolatedMode Applicability:AllBasis:GenericThis EAL addresses radioactivity releases that result in doses at or beyond the site boundary thatexceed 10% of the EPA Protective Action Guides (PAGs). Releases of this magnitude areassociated with the failure of plant systems needed for the protection of the public.February 201643EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearThe site specific monitor list in Table R-1 includes effluent monitors on all potential releasepathways.Since dose assessment is based on actual meteorology, whereas the monitor reading EAL is not,the results from these assessments may indicate that the classification is not warranted, or mayindicate that a higher classification is warranted. For this reason, emergency implementingprocedures should call for the timely performance of dose assessments using actual meteorologyand release information. If the results of these dose assessments are available when theclassification is made (e.g., initiated at a lower classification level), the dose assessment resultsoverride the monitor reading EAL.Plant-SpecificThe Emergency Director (ED) should not wait until 15 minutes has elapsed, but should declare theevent as soon as it is determined that the release duration has or will likely exceed 15 minutes.A description of the applicable monitors and the methods used to calculate EAL values for theWRNGM is shown in RU1.1. Values for this EAL are based on the values shown in RU1.1 scaledup from 0.114 mrem in an hour (iLe., hourly rate resulting in 2 X 500 mrem in one year) to 100mrem (TEDE) (1 mSV) in an hour.The meteorology and source term (noble gases) used in determining the monitor readings in EALRSI.1 are the same as those used for determining the monitor readings in EALs RU1.1 andRA1 .1. Consistent use of these variables for all three EALs creates a protocol that maintainsconsistent intervals between the monitor readings for the four emergency classifications. Themonitor readings developed with this protocol are intended to be used only in situations in whichnormal dose assessment cannot be accomplished. Normal dose assessment methods incorporatethe actual accident meteorological variables and are the preferred methods for determining whenthis EAL is met.In keeping with this protocol, the monitor response release coefficient for a steam generator tuberupture contaminated with RCS activity is used rather than the release coefficient for a steamgenerator tube rupture contaminated with gap activity. This choice of source terms may appear tobe non-conservative. It is important to consider, however, that the EALs in other categoriescompensate for the apparent lack of conservatism. A loss or challenge to plant safety systems is aprecursor EAL for a radiological release of this magnitude. Furthermore, normal dose assessmentis the primary method for determining the offsite consequences and takes into account accidentmeteorology and source term.February 2016 44 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearRS1.1 Threshold for RIC-5415Scale up from RUI .1 uncorrected release rate of 3.6 E+5 pCi/secRSI.1 Value =100 mRem/hr x 3.6 E+5 uCi/sec0.114 mRem/hr (or .00114 mSv/hr)=3.2 E+8 pCi/secThis value corresponds to a concentration of about 5 pCi/cc and falls well within the range of theWRNGM.The purpose of the Main Steam Effluent Radiation Monitor System is to monitor possible noble gasreleases to the atmosphere from the main steam line through the atmospheric steam dump valves,the main steam safety relief valves and the auxiliary feedwater steam turbine exhaust. The systemincludes two radiation monitors (1/2-RI-5421 and 1/2-RI-5422) per unit -one radiation monitor foreach steam generator.The noble gas release rate of 3.2E+8 IpCi/sec (which corresponds a whole body dose of 100 mremin one hour at the site boundary) may also occur through release via the main steam safety valveor atmospheric dump valve.EP-CALC-00001, Determination of Emergency Action Level Criteria for Calvert Cliffs NuclearPower Plant Main Steam Line Radiation Monitors, outlines, in detail, the calculation andmethodology demonstrated below.RAI.1 Threshold for RIC-5421, RIC-5422RG1.1 Threshold Value = 2.99 E+4 IpCi/cc (see section RGI.1)GE Site Boundary Dose Threshold = 1000 mremSAE Site Boundary Dose Threshold = 100 mremMain Steam Monitor Reading (pCi/cc) =SAE. Site Boundary Dose Threshold X RGL.1 Threshold ValueGE Site Boundary Dose Threshold_100 mrem X29 tic-loeo mrem X29 iic= 2.99 E+3 pCi/ccFebruary 201645EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBased on the March 14, 1993 SG tube rupture event at Palo Verde Unit 2, the main steam effluentmonitors (RI-5421, RI-5422) may read N16 immediately following SG tube rupture and prior toreactor trip. However, given the short half-life of N16, this should clear within the first minutefollowing reactor trip.Dose assessment performed in accordance with ERPIP 822, Initial Dose Assessment ManualCalculation Methods, or EP-AA-1 10-202, CCNPP Dose Assessment, is based on actualmeteorology but the monitor reading thresholds in this EAL are based on assumed meteorology.As a result, dose assessment may indicate that emergency classification is not warranted, eventhough the monitor reading threshold has been exceeded. For this reason, emergencyimplementing procedures call for the timely performance of dose assessments using actualmeteorology and release information. If the results of dose assessments are available whenemergency classification is being evaluated (e.g., initiated at a lower classification level), the doseassessment results override the monitor readings listed in Table R-1.The designation "N/A" in Table R-1 indicates that the listed instrument range is insufficient toindicate the specified value and therefore no value is used.A radiation monitor reading is valid when a release path is established. If the release path to theenvironment has been isolated, the radiation monitor reading is not valid for classification.CCNPP Basis Reference(s):1. Radioactivity Release Emergency Action Levels, J.B. Mcllvaine, JSB Associates, Inc.,September 19902. Off-Site Dose Calculation Manual (ODCM) for the Calvert Cliffs Nuclear Power Plant3. ERPIP 822, Initial Dose Assessment Manual Calculation Methods4. EP-AA-110-202, CCNPP Dose Assessment5. NEI 99-01 ASi6. EP-CALC-QOO01, Determination of Emergency Action Level Criteria for Calvert Cliffs NuclearPower Plant Main Steam Line Radiation MonitorsFebruary 2016 46 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:R -Abnormal Rad Release / Rad Effluent1 -Offsite Rad ConditionsInitiating Condition: Offsite dose resulting from an actual or imminent release of gaseousradioactivity exceeds 100 mRem TEDE or 500 mRem thyroid CDE forthe actual or projected duration of the release using actualmeteorologyEAL:RSI .2 Site Area EmergencyDose assessment using actual meteorology indicates doses > 100 mRem TEDE or500 mRem thyroid ODE at or beyond the site boundaryMode Applicability:AllBasis:GenericThis EAL addresses radioactivity releases that result in doses at or beyond the site boundary thatexceed 10% of the EPA Protective Action Guides (PAGs). Releases of this magnitude areassociated with the failure of plant systems needed for the protection of the public.Since dose assessment is based on actual meteorology, whereas the monitor reading EAL is not,the results from these assessments may indicate that the classification is not warranted, or mayindicate that a higher classification is warranted. For this reason, emergency implementingprocedures should call for the timely performance of dose assessments using actual meteorologyand release information. If the results of these dose assessments are available when theclassification is made (e.g., initiated at a lower classification level), the dose assessment resultsoverride the monitor reading EAL.Plant-SpecificThe 100 mRem TEDE dose is set at 10% of the EPA PAG, while the 500 mRem thyroid ODE wasestablished in consideration of the 1:5 ratio of the EPA PAG for TEDE and thyroid ODE.The site boundary is depicted on CCNPP 0DCM Attachment 18 "Environmental Monitoring Sites"(ref. 1). The site boundary is approximately a one-mile radius around the Protected Area. Per doseassessment methodology, the SB designated the Exclusion Area Boundary (EAB) is defined as1150 meters (0.71- miles), which is the minimum distance to the SB. ERPIP-822 assumes a SB orEAB of 0.7 miles.February 201647EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclea~rCCNPP Basis Reference(s):1. 0ff-Site Dose Calculation Manual (00CM) for the Calvert Cliffs Nuclear Power Plant2. ERPIP 822, Initial Dose Assessment Manual Calculation Methods3. NEI 99-01 AS1February 201648EP-AA-1 011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert AnnexFxI~xnn N~irlIn:ar......... I mIV I ....... I m m Category:Su bcategory:Initiating Condition:R -Abnormal Rad Release/IRad Effluent1 -Offsite Rad ConditionsOffsite dose resulting from an actual or imminent release ofgaseous radioactivity exceeds 100 mRem TEDE or 500 mRemthyroid CDE for the actual or projected duration of the releaseusing actual meteorologyEAL:RS1 .3 Site Area EmergencyField survey results indicate closed window dose rates > 100 mRem/hr expected tocontinue for _> 60 min. at or beyond the site boundaryORAnalyses of field survey samples indicate thyroid CDE > 500 mRem for 1 hr of inhalation ator beyond the site boundary (Note 1)determined that the condition will likely exceed the applicable timeMode Applicability:AllBasis:GenericThis EAL addresses radioactivity releases that result in doses at or beyond the site boundary thatexceed 10% of the EPA Protective Action Guides (PAGs). Releases of this magnitude areassociated with the failure of plant systems needed for the protection of the public.Since dose assessment is based on actual meteorology, whereas the monitor reading EAL is not,the results from these assessments may indicate that the classification is not warranted, or mayindicate that a higher classification is warranted. For this reason, emergency implementingprocedures should call for the timely performance of dose assessments using actual meteorologyand release information. If the results of these dose assessments are available when theclassification is made (e.g., initiated at a lower classification level), the dose assessment resultsoverride the monitor reading EAL.February 201649EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryAnnAxF:vAlnn N~mlcil~rVI b VII IV I II II I I Plant-SpecificThe site boundary is depicted on CCNPP ODCM Attachment 18 "Environmental Monitoring Sites"(ref. 1). The site boundary is approximately a one-mile radius around the Protected Area. Per doseassessment methodology, the SB designated the Exclusion Area Boundary (EAB) is defined as1150 meters (0.71 miles), which is the minimum distance to the SB. ERPIP-822 assumes a SB orEAB of 0.7 miles.CCNPP Basis Reference(s):1. Off-Site Dose Calculation Manual (0DCM) for the Calvert Cliffs Nuclear Power Plant2. NEI 99-01 AS1February 201650EP-AA-1 011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:Initiating Condition:R -Abnormal Rad Release/IRad Effluent1 -Offsite Rad ConditionsOffsite dose resulting from an actual or imminent release ofgaseous radioactivity greater than 1,000 mRem TEDE or 5,000mRem thyroid CDE for the actual or projected duration of therelease using actual meteorologyEAL:RGI.1 General EmergencyANY radiation monitor reading > Table R-1 column "GE" for > 15 min. (Note 1)* Do not delay declaration awaiting dose assessment results* If dose assessment results are available, declaration should be based on doseassessment instead of radiation monitor values (see EAL RG1 .2)Note 1: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition will likely exceed the applicable timeTable R-1 Effluent Monitor Classification ThresholdsMonitor [ GE ] SAE Alert UEGaseousWRNGM 3.2E+09 pCi/sec 3.2E+08 pCi/sec 3.2E+07 pCi/sec 3.2E+05 pCi/sec(RIC-541 5)Main Steam Effluent 2.99E+04 ~tCi/cc 2.99E+'03 2.99E+02 p.Ci/cc N/A(RIC-5421/5422)Main Vent N/A N/A N/A 2.0E+05 cpm(RI-541 5)Waste Processing N/A N/A N/A 4.0E+05 cpm(RI-541 0)Fuel Handling Area Vent N/A N/A N/A 3.4E+05 cpm(RI-5420)Liquid Waste Disch* N/A N/A N/A 8.4E+05 cpm(RE-2201)* with effluent discharge not isolatedMode Applicability:AllBasis:GenericThis EAL addresses radioactivity releases that result in doses at or beyond the site boundary thatexceed the EPA Protective Action Guides (PAGs). Public protective actions will be necessary.Releases of this magnitude are associated with the failure of plant systems needed for theprotection of the public and likely involve fuel damage.February 201651EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearThe monitor list in Table R-1 includes effluent monitors on all potential release pathways.Since dose assessment is based on actual meteorology, whereas the monitor reading EAL is not,the results from these assessments may indicate that the classification is not warranted, or mayindicate that a higher classification is warranted. For this reason, emergency implementingprocedures should call for the timely performance of dose assessments using actual meteorologyand release information. If the results of these dose assessments are available when theclassification is made (e.g., initiated at a lower classification level), the dose assessment resultsoverride the monitor reading EAL.Plant-SpecificA description of the applicable monitors and the methods used to calculate EAL values for theWRNGM is shown in EAL RU1.1. Values for this EAL are based on the values shown in RU1.1scaled up from 0.114 mrem in an hour (iLe., hourly rate resulting in 2 X 500 mrem in one year) to1000 mrem (TEDE) (10 mSV) in an hour.The meteorology and source term (noble gases) used in determining the monitor reading EAL inRG1 .1 are the same as those used for determining the monitor reading EALs in EALs RU1 .1,RA1.1 and RS1.1. Consistent use of these variables for all four EALs creates a protocol thatmaintains consistent intervals between the monitor readings for the four emergency classifications.The monitor readings developed with this protocol are intended to be used only in situations inwhich normal dose assessment cannot be accomplished. Normal dose assessment methodsincorporate the actual accident meteorological variables and are the preferred methods fordetermining when this EAL is met.In keeping with this protocol, the monitor response release coefficient for a steam generator tuberupture contaminated with RCS activity is used rather than the release coefficient for a steamgenerator tube rupture contaminated with gap activity. This choice of source terms may appear tobe non-conservative. The EALs in other categories compensate for this apparent lack ofconservatism. A loss or challenge to plant safety systems is a precursor EAL for a radiologicalrelease of this magnitude. Normal dose assessment is the primary method for determining theoffsite consequences and takes into account the accident meteorology and source term.February 2016 52 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryAnnc'vFvI:,lnn rL vimiiv i t iiiv kAVIVI I i 1 twI V I ira((14 IRG1.1 Threshold for RIC-5415Scale up from RUI .1 uncorrected release rate of 3.6 E+5 pCi/secRGI.1 Value = 1000 mRem/hr x 3.6 E+5 uJCi/sec0.114 mRem/hr (or .00114 mSvlhr)= 3.2 E+9 pJCi/secThis value corresponds to a concentration of about 50 IpCi/cc and falls well within the range of theWRNGM.The purpose of the Main Steam Effluent Radiation Monitor System is to monitor possible noble gasreleases to the atmosphere from the main steam line through the atmospheric steam dump valves,the main steam safety relief valves, and the auxiliary feedwater steam turbine exhaust. The systemincludes two radiation monitors (1/2-RI-5421 and 1/2-RI-5422) per unit -one radiation monitor foreach steam generator.The noble gas release rate of 3.2 E+9 IpCi/sec (which corresponds a whole body dose of 1000mrem in one hour at the site boundary) may also occur through release via main steam safetyvalve or atmospheric dump valve.February 201653EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryAnnoyNnnr~tl.rEP-CALC-OOO01, Determination of Emergency Action Level Criteria for Calvert Cliffs NuclearPower Plant Main Steam Line Radiation Monitors, outlines, in detail, the calculation andmethodolodgy demonstrated below:RG1.1 Threshold for RIC-542i, RIC-5422Release Rate = 3.2 E+9 pCi/sec (see above)Safety Valve Flow Rate = 2.44 E+6 cc/secRelease Concentration (pJCi/cc) =Release RateSafety Valve Flow Rate= 3.2 E+9 uJCi/cc2.44 E+6 cc/sec=1.31 E+3 pJCi/ccDetector response factors were applied to obtain a Main Steam Monitor reading of:2.99 E+4 pCilccBased on the March 14, 1993 SG tube rupture event at Palo Verde Unit 2, the main steam effluentmonitors (RIC-5421, RIC-5422) may read N16 immediately following SG tube rupture and prior toreactor trip. However, given the short half-life of N16, this should clear within the first minutefollowing reactor trip.Dose assessment performed in accordance with ERPIP 822, Initial Dose Assessment ManualCalculation Methods, or EP-AA-1 10-202, CCNPP Dose Assessment, is based on actualmeteorology but the monitor reading thresholds in this EAL are based on assumed meteorology.As a result, dose assessment may indicate that emergency classification is not warranted, eventhough the monitor reading threshold has been exceeded. For this reason, emergencyimplementing procedures call for the timely performance of dose assessments using actualmeteorology and release information. If the results of dose assessments are available whenemergency classification is being evaluated (e.g., initiated at a lower classification level), the doseassessment results override the monitor readings listed in Table R-I.February 201654EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearThe designation "N/A" in Table R-1 indicates that the listed instrument range is insufficient toindicate the specified value and therefore no value is used.A radiation monitor reading is valid when a release path is established. If the release path to theenvironment has been isolated, the radiation monitor reading is not valid for classification.CCNPP Basis Reference(s):1. Radioactivity Release Emergency Action Levels, J.B. Mcllvaine, JSB Associates, Inc.,September 19902. Off-Site Dose Calculation Manual (00CM) for the Calvert Cliffs Nuclear Power Plant3. ERPIP 822, Initial Dose Assessment Manual Calculation Methods4. EP-AA-1 10-202, CCNPP Dose Assessment5. NEI 99-01 AG16. EP-CALC-00001, Determination of Emergency Action Level Criteria for Calvert Cliffs NuclearPower Plant Main Steam Line Radiation MonitorsFebruary 201655EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:R -Abnormal Rad Release / Rad Effluent1 -Offsite Rad ConditionsInitiating Condition: Offsite dose resulting from an actual or imminent release ofgaseous radioactivity greater than 1,000 mRem TEDE or 5,000mRem thyroid CDE for the actual or projected duration of therelease using actual meteorologyEAL:RGI.2 General EmergencyDose assessment using actual meteorology indicates doses > 1,000 mRem TEDE or5,000 mRem thyroid CDE at or beyond the site boundaryMode Applicability:AllBasis:GenericThis EAL addresses radioactivity releases that result in doses at or beyond the site boundary thatexceed the EPA Protective Action Guides (PAGs). Public protective actions will be necessary.Releases of this magnitude are associated with the failure of plant systems needed for theprotection of the public and likely involve fuel damage.Since dose assessment is based on actual meteorology, whereas the monitor reading EAL is not,the results from these assessments may indicate that the classification is not warranted, or mayindicate that a higher classification is warranted. For this reason, emergency implementingprocedures should call for the timely performance of dose assessments using actual meteorologyand release information. If the results of these dose assessments are available when theclassification is made (e.g., initiated at a lower classification level), the dose assessment resultsoverride the monitor reading EAL.Plant-SpecificThe 1,000 mRem TEDE dose is set at 100% of the EPA PAG, while the 5,000 mRem thyroid ODEwas established in consideration of the 1:5 ratio of the EPA PAG for TEDE and thyroid ODE.The site boundary is depicted on CCNPP ODCM Attachment 18 "Environmental Monitoring Sites"(ref. 1). The site boundary is approximately a one-mile radius around the Protected Area. Per doseassessment methodology, the SB designated the Exclusion Area Boundary (EAB) is defined as1150 meters (0.71 miles), which is the minimum distance to the SB. ERPIP-822 assumes a SB orEAB of 0.7 miles.February 201656EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryC.nlvwrt AnncoyFvclnn rW MR Vml B mY B II me i i CCNPP Basis Reference(s):1. Off-Site Dose Calculation Manual (ODCM) for the Calvert Cliffs Nuclear Power Plant2. ERPIP 822, Initial Dose Assessment Manual Calculation Methods3. NEI 99-01 AG1February 201657EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuc~learCategory:R -Abnormal Rad Release / Rad EffluentSubcategory: 1 -Offsite Rad ConditionsInitiating Condition: Offsite dose resulting from an actual or imminent release ofgaseous radioactivity greater than 1,000 mRem TEDE or 5,000mRem thyroid CDE for the actual or projected duration of therelease using actual meteorologyEAL:RGI.3 General EmergencyField survey results indicate closed window dose rates > 1,000 mRem/hr expected tocontinue for _> 60 mai. at or beyond the site boundaryORAnalyses of field survey samples indicate thyroid CDE > 5,000 mRem for 1 hr of inhalationat or beyond the site boundary (Note 1)determined that the condition will likely exceed the applicable timeMode Applicability:AllBasis:GenericThis EAL addresses radioactivity releases that result in doses at or beyond the site boundary thatexceed the EPA Protective Action Guides (PAGs). Public protective actions will be necessary.Releases of this magnitude are associated with the failure of plant systems needed for theprotection of the public and likely involve fuel damage.Since dose assessment is based on actual meteorology, whereas the monitor reading EAL is not,the results from these assessments may indicate that the classification is not warranted, or mayindicate that a higher classification is warranted. For this reason, emergency implementingprocedures should call for the timely performance of dose assessments using actual meteorologyand release information. If the results of these dose assessments are available when theclassification is made (e.g., initiated at a lower classification level), the dose assessment resultsoverride the monitor reading EAL.February 201658EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearPlant-SpecificThe site boundary is depicted on CCNPP ODCM Attachment 18 "Environmental Monitoring Sites"(ref. 1). The site boundary is approximately a one-mile radius around the Protected Area. Per doseassessment methodology, the SB designated the Exclusion Area Boundary (EAB) is defined as1150 meters (0.71 miles), which is the minimum distance to the SB. ERPIP-822 assumes a SB orEAB of 0.7 miles.CCNPP Basis Reference(s):1. Off-Site Dose Calculation Manual (ODOM) for the Calvert Cliffs Nuclear Power Plant2. NE! 99-01 AG1February 201659EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexF::Alnn Nucrlear...................... m m Category:R -Abnormal Rad Release /Rad EffluentSubcategory: 2 -Onsite Rad Conditions & Spent Fuel EventsInitiating Condition: Unplanned rise in plant radiation levelsEAL:RU2.1 Unusual EventUNPLANNED water level drop in a reactor refueling pathway as indicated by ANY of thefollowing (Note 3):* Inability to restore and maintain SEP level > Technical Specification limit (65 ft 7 in)* Inability to restore and maintain REP level > Technical Specification limit (56 ft 8.5in)* Report of visual observation of an uncontrolled drop in water level in the REP orSEPANDArea radiation monitor reading rise on ANY of the following:* SEP Area RM-320 EL-69 (0RIC-7023 Channel 4)* Spent Fuel Handling Machine (0RIC-7023 Channel 3)* Unit 1/2 CNTMT EL-69 (RI-53I6A/B/C/D)EALs CU3.1, CU3.2 or CU3.3Mode Applicability:AllBasis:GenericThis EAL addresses increased radiation levels as a result of water level decreases aboveirradiated fuel or events that have resulted, or may result, in unplanned increases in radiation doserates within plant buildings. These radiation increases represent a loss of control over radioactivematerial and represent a potential degradation in the level of safety of the plant.The refueling pathway is a combination of cavities, tubes, canals and pools. While a radiationmonitor could detect an increase in dose rate due to a drop in the water level, it might not be areliable indication of whether or not the fuel is covered.For refueling events where the water level drops below the RPV flange classification would be viaEAL CU3.1, CU3.2 or CU3.3. This event escalates to an Alert per EAL RA2.1 if irradiated fueloutside the reactor vessel is uncovered. For events involving irradiated fuel in the reactor vessel,escalation would be via the Fission Product Barrier Table for events in operating modes 1-4.February 201660EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearPlant-SpecificThe reactor refueling pool (REP), spent fuel pool (SEP) and fuel transfer canal comprise therefueling pathway.The Spent Fuel Pool (SFP) is normally filled with borated water to a level of 67 ft. The SEP isequipped with a level switch in each half that actuates a low level alarm at 66 ft 6 in. The minimumlevel per Technical Specifications is 65 feet, 8.5 inches (21 feet, 6 inches above the fuel seated inthe SFP) (ref. 6). The phrase "... inability to restore and maintain.., level >..." allows the operator tovisually observe the low water level condition, if possible, and to attempt water level restorationinstructions as long as water level remains above the top of irradiated fuel.When the fuel transfer canal is directly connected to the spent fuel pool and refueling pool, therecould exist the possibility of uncovering irradiated fuel in the fuel transfer canal. Therefore, this EALis applicable to cold conditions in which irradiated fuel is being transferred to and from the ReactorVessel and refueling pool. In hot conditions, the refueling pool is empty and this EAL would applyto irradiated fuel in the spent fuel pool.Technical Specifications requires that refueling pool water level be maintained 23 ft aboveirradiated fuel seated in the Reactor Vessel when moving fuel.While a radiation monitor could detect a rise in dose due to a drop in the water level, it might not bea reliable indication, in and of itself, of whether or not the fuel is uncovered. For example, thereading on an area radiation monitor located on the refueling bridge may rise due to plannedevolutions such as head lift, or even a fuel assembly being raised in the manipulator mast.Elevated radiation monitor indications will need to be combined with another indicator (orpersonnel report) of water loss.This event escalates to an Alert if irradiated fuel outside the reactor vessel is uncovered.Definitions:UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.February 2016 61 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelnn NuclIearCCNPP Basis Reference(s):1. AOP-6E Loss of Refueling Pool Level2. System Description No. 67/68 Spent Fuel Pool and Cooling System3. Shutdown Safety Surveillance H (Fuel Movement Observation)4. Technical Specifications Section 3.9.6 Refueling Pool Water Level5. Technical Specifications Section 3.7.13 SEP Water Level7. TS-05.O1 Technical Specification Action Value Bases Document8. NEI 99-01 AU2February 201662EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexE~I~xnn NiitIlz~r...................... B m iNvmvMmCategory:Subcategory:R -Radioactivity Release / Area Radiation2 -Onsite Rad Conditions & Spent Fuel EventsInitiating Condition: Unplanned rise in plant radiation levelsEAL:RU2.2 Unusual EventUNPLANNED area radiation readings increases by a factor of 1,000 over NORMAL LEVELSMode Applicability:AllBasis:GenericThis EAL addresses increased radiation levels as a result of water level decreases aboveirradiated fuel or events that have resulted, or may result, in unplanned increases in radiation doserates within plant buildings. These radiation increases represent a loss of control over radioactivematerial and represent a potential degradation in the level of safety of the plant.This EAL addresses increases in plant radiation levels that represent a loss of control ofradioactive material resulting in a potential degradation in the level of safety of the plant.This EAL excludes radiation level increases that result from planned activities such as use ofradiographic sources and movement of radioactive waste materials. A specific list of ARMs is notrequired as it would restrict the applicability of the threshold. The intent is to identify loss of controlof radioactive material in any monitored area.Plant-SpecificAssessment of this EAL may be made with survey readings using portable instruments as well asinstalled radiation monitors.Definitions:UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.Normal LevelsAs applied to radiological IC/EALs, the highest reading in the past twenty-four hours excludingthe current peak value.CCNPP Basis Reference(s):1. NEI 99-01 AU2February 201663EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:R -Abnormal Rad Release / Rad Effluent2 -Onsite Rad Conditions & Spent Fuel EventsInitiating Condition: Damage to irradiated fuel or loss of water level that has resulted orwill result in the uncovering of irradiated fuel outside the ReactorVesselEAL:RA2.1 AlertAlarm on ANY of the following radiation monitors due to damage to irradiated fuel or lossof water level:* Fuel Handling Area Vent (RI-5420)* SEP Area RM-320 EL-69 (0RIC-7023 Channel 4)* Spent Fuel Handling Machine (0RIC-7023 Channel 3)* Unit 1/2 CNTMT EL-69 (RI-5316AIBICID)Mode Applicability:AllBasis:GenericThis EAL addresses increases in radiation dose rates within plant buildings, and may be aprecursor to a radioactivity release to the environment. These events represent a loss of controlover radioactive material and represent an actual or substantial potential degradation in the level ofsafety of the plant.This EAL addresses radiation monitor indications of fuel uncovery and/or fuel damage.Increased ventilation monitor readings may be indication of a radioactivity release from the fuel,confirming that damage has occurred. Increased background at the ventilation monitor due towater level decrease may mask increased ventilation exhaust airborne activity and needs to beconsidered.While a radiation monitor could detect an increase in dose rate due to a drop in the water level, itmight not be a reliable indication of whether or not the fuel is covered.Escalation of this emergency classification level, if appropriate, would be based on RS1.1, RS1.2,RS1.3, RGI.1, RGI.2 or RG1.3.Plant-SpoecificThis EAL is defined by the specific areas where irradiated fuel is located such as the refueling pool,reactor vessel, or spent fuel pool.February 201664EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearThe bases for the area radiation high alarms and Containment radiation high alarms are a spentfuel handling accident and are, therefore, appropriate for this EAL. Elevated readings on ventilationmonitors may also be indication of a radioactivity release from the fuel, confirming that damage hasoccurred. However, elevated background at the monitor due to water level lowering may maskelevated ventilation exhaust airborne activity and needs to be considered. However, while radiationmonitors may detect a rise in dose rate due to a drop in the water level, it might not be a reliableindication of whether or not the fuel is covered. The following are examples of events in which themonitor could be responding properly yet not signaling damage to or uncovery of irradiated fueloutside the reactor vessel:* Transfer or relocation of a source stored in or near the fuel pool.* A planned evolution such as removal of the reactor head.* Movement of spent fuel with fuel rods that have been known to be leaking.Interpretation of these EAL thresholds requires some understanding of the actual radiologicalconditions present in the vicinity of the monitors.CCNPP Basis Reference(s):1. 1I(2)AOP-6E Loss of Refueling Pool Level2. OP-07 Shutdown Operations, Section 6.9.B Checklist for Fuel Movement"3. NEI 99-01 AA2February 201665EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:Initiating Condition:R -Abnormal Rad Release / Rad Effluent2 -Onsite Rad Conditions & Spent Fuel EventsDamage to irradiated fuel or loss of water level that has resulted orwill result in the uncovering of irradiated fuel outside the ReactorVesselEAL:Mode Applicability:AllBasis:GenericThis event represents a loss of control over radioactive material and represent an actual orsubstantial potential degradation in the level of safety of the plant.Escalation of this emergency classification level, if appropriate, would be based on RS1.1, RSI.2,RS1.3, RGI.1, RG1.2 or RG1.3.Plant-SpecificThis EAL is defined by the specific areas where irradiated fuel is located such as the refueling pool,Reactor Vessel or Spent Fuel Pool.There is no direct indication that water level in the Spent Fuel Pool or refueling pool has dropped tothe level of the fuel other than visual observation. Since there is no level indicating system in thefuel transfer canal, visual observation of loss of water level would also be required. If available,video cameras may allow remote observation. Depending on available level indication, thedeclared threshold may need to be based on indications of makeup rate or lowering in RefuelingWater Storage Tank level (ref. 1).The movement of irradiated fuel assemblies within Containment requires a minimum water level of23 ft above the Reactor Vessel flange and the top of spent fuel in the SEP. During refuelingactivities, this maintains sufficient water level in the refueling cavity, fuel transfer canal and SEP.Sufficient water is necessary to retain iodine fission product activity in the water in the event of afuel handling accident (ref. 2, 3).February 201666EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearAllowing level to decrease could result in spent fuel being uncovered, reducing spent fuel decayheat removal and creating an extremely hazardous radiation environment.CCNPP Basis Reference(s):1. 1(2) AOP-6E Loss of Refueling Pool Level2. Technical Specifications Section 3.9.6 Refueling Pool Water Level3. Technical Specifications Section 3.7.13 SFP Water Level4. NEI 99-01 AA2February 201667EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:R -Abnormal Rad Release / Rad Effluent3 -CR/CAS RadInitiating Condition: Rise in radiation levels within the facility that impedes operation ofsystems required to maintain plant safety functionsEAL:RA3.1 AlertDose rates > 15 mRem/hr in ANY of the following areas requiring continuous occupancy tomaintain plant safety functions:* Control Room* CASMode Applicability:AllBasis:GenericThis EAL addresses increased radiation levels that: impact continued operation in areas requiringcontinuous occupancy to maintain safe operation or to perform a safe shutdown.The cause and/or magnitude of the increase in radiation levels is not a concern of this EAL. TheEmergency Director must consider the source or cause of the increased radiation levels anddetermine if any other EAL may be involved.Areas requiring continuous occupancy include the Control Room and any other control stationsthat are staffed continuously, such as the security alarm station CAS.Plant-SpecificThe Control Room and Central Alarm Station (CAS) must be continuously occupied in all plantoperating modes at CCNPP.There is no area radiation monitoring system at CCNPP for the Control Room or CAS. Abnormalradiation levels may be initially detected by the Control Room vent supply radiation monitor, routineradiological surveys and abnormal responses from electronic personnel dosimeters worn bypersonnel occupying these spaces.CCNPP Basis Reference(s):1. System Description # 77/79 Radiation Monitoring System2. UFSAR Section 11.2.2.5 Auxiliary Building Shielding3. NEI 99-01 AA3February 201668EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory E -Independent Spent Fuel Storage Installation (ISFSIIDSC)EAL Group: Not Applicable (the EAL in this category isapplicable independent of plant operating mode)An independent spent fuel storage installation (ISESI) is a complex that is designed andconstructed for the interim storage of spent nuclear fuel and other radioactive materials associatedwith spent fuel storage. A significant amount of the radioactive material contained within acask/canister must escape its packaging and enter the biosphere for there to be a significantenvironmental effect resulting from an accident involving the dry storage of spent nuclear fuel.Formal offsite planning is not required because the postulated worst-case accident involving anISESI has insignificant consequences to the public health and safety.A Notification of Unusual Event is declared on the basis of the occurrence of an event of sufficientmagnitude that a loaded cask confinement boundary is damaged or violated. This includesclassification based on a loaded fuel storage cask/canister confinement boundary loss leading tothe degradation of the fuel during storage or posing an operational safety problem with respect toits removal from storage.A hostile security event that leads to a potential loss in the level of safety of the ISESI is aclassifiable event under Security category EAL HA4. 1.Minor surface damage that does not affect storage cask/canister boundary is excluded from thescope of these EALs.February 201669EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: E -ISFSI/DSCSubcategory: Not ApplicableInitiating Condition: Damage to a loaded cask confinement boundaryEAL:EUI.1 Unusual EventDamage to a loaded cask CONFINEMENT BOUNDARYMode Applicability:Not applicableBasis:GenericAn UE in this EAL is categorized on the basis of the occurrence of an event of sufficient magnitudethat a loaded cask confinement boundary is damaged or violated. This includes classificationbased on a loaded fuel storage cask confinement boundary loss leading to the degradation of thefuel during storage or posing an operational safety problem with respect to its removal fromstorage.This EAL addresses a dropped cask, a tipped over cask, EXPLOSION, PROJECTILE damage,FIRE damage or natural phenomena affecting a cask (e.g., seismic event, tornado, etc.).Plant-SpecificThe CCNPP ISESI utilizes the NUHOMS dry spent fuel storage system.This EAL addresses any condition which indicates a loss of a cask confinement boundary and thusa potential degradation in the level of safety of the ISESI. The cask confinement boundary isconsidered the Dry Shielded Canister (DSC).Definitions:Confinement BoundaryThe barrier(s) between areas containing radioactive substances and the environment.Independent Spent Fuel Storage Installation (ISFSI)A complex that is designed and constructed for the interim storage of spent nuclear fuel andother radioactive materials associated with spent fuel storage.CCNPP Basis Reference(s):1. Calvert Cliffs ISESI USAR2. NEI 99-01 E-HU1February 2016 70 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory C -Cold Shutdown I Refueling System MalfunctionEAL Group: Cold Conditions (RCS temperature -< 200°F); EALsin this category are applicable only in one or morecold operating modes.Category C EALs are directly associated with cold shutdown or refueling system safety functions.Given the variability of plant configurations (e.g., systems out-of-service for maintenance,Containment open, reduced AC power redundancy, time since shutdown) during these periods, theconsequences of any given initiating event can vary greatly. For example, a loss of decay heatremoval capability that occurs at the end of an extended outage has less significance than a similarloss occurring during the first week after shutdown. Compounding these events is the likelihoodthat instrumentation necessary for assessment may also be inoperable. The cold shutdown andrefueling system malfunction EALs are based on performance capability to the extent possible withconsideration given to RCS integrity, Containment closure, and fuel clad integrity for the applicableoperating modes (5 -Cold Shutdown, 6 -Refuel, 0 -Defueled).The events of this category pertain to the following subcategories:1. Loss of AC PowerLoss of emergency plant electrical power can compromise plant safety system operabilityincluding decay heat removal and emergency core cooling systems which may be necessary toensure fission product barrier integrity. This category includes loss of onsite and offsite powersources for the 4 kV safeguard buses.2. Loss of DC PowerLoss of emergency plant electrical power can compromise plant safety system operabilityincluding decay heat removal and emergency core cooling systems which may be necessary toensure fission product barrier integrity. This category includes loss of power to the 125 VDCbuses.February 2016 71 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclear3. ROS LevelReactor Vessel or RCS water level is directly related to the status of adequate core coolingand, therefore, fuel clad integrity. RCS levels associated with Category C EALs are listed inTable 0-5.4. RCS TemperatureUncontrolled or inadvertent temperature or pressure increases are indicative of a potential lossof safety functions.5. CommunicationsCertain events that degrade plant operator ability to effectively communicate with essentialpersonnel within or external to the plant warrant emergency classification.6. Inadvertent CriticalityInadvertent criticalities pose potential personnel safety hazards as well being indicative oflosses of reactivity control.February 201672EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:C -Cold Shutdown / Refueling System MalfunctionSubcategory: 1 -Loss of AC PowerInitiating Condition: AC power capability to 4kV vital buses reduced to a single powersource for 15 min. such that ANY additional single failure wouldresult in a complete loss of all 4kV vital bus powerEAL:CUI.1 Unusual EventAC power capability to 4kV vital buses 11(21) and 14(24) reduced to a single powersource, Table C-I, for_> 15 min. (Note 4)ANDANY additional single power source failure will result in a complete loss of all 4kV vital buspowerNote 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time.Table C-I AC Power Sources* 1(2)A DG"n

• 1(2)B DG0 0C DG, if aligned* 500kV transmission line 5051** 500kV transmission line 5052** a 500kV transmission line 5072*O

• SMECO line ,if aligned* A credited 500kV line must have anindependent 13kV service transformerMode Applicability:5 -Cold Shutdown, 6 -Refuel, D -DefueledBasis:GenericThe condition indicated by this EAL is the degradation of the off-site and on-site AC power systemssuch that any additional single failure would result in a complete loss of 4 kV vital bus AC power toone or both units. This condition could occur due to a loss of off-site power with a concurrent failureFebruary 201673EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearof all but one emergency generator to supply power to its emergency bus. The subsequent loss ofthis single power source would escalate the event to an Alert in accordance with EAL CA1 .1.Fifteen minutes was selected as a threshold to exclude transient or momentary losses of power.Plant-SpecificCCNPP essential buses are 4kV vital buses 11 (21) and 14(24). There are five offsite powersources available to these buses:*Three 500kV transmission lines (Lines 5051, 5052, and 5072) supply offsite power to the500kV switchyard via the transmission network.oOne 69kV/1 3kV Southern Maryland Electric Cooperative (SMECO) line may be manuallyconnected to either 13kV bus and then to the 4kV vital buses. Under certain operationalconditions, 13kV bus(es) may be receiving power from SMECO or may be quicklyconnected to the SMECO tie-line. The SMECO line is not used to carry loads for anoperating unit and may provide power to no more than two 4kV vital buses simultaneously.oIf a fault affects only one unit, power may be obtained from the 500kV supply of theunaffected unit through a single 13kV transformer. This is considered an offsite AC powersource available to the affected unit.Based on operational experience, if the SMECO line or the 0C DG is not already aligned, thesecannot be considered available/capable of supplying the bus due to the time it will take to alignthem. In any case, if this cannot be accomplished within 15 minutes, they are not available and anUnusual Event must be declared.In-house power is fed back from the 500KV ring bus through 2 13kV transformers (designated P-13000-1 and P-i13000-2). Normally P-i13000-1 supplies all of Unit -1 (except 14 4kV bus) and 214kV bus. P-i13000-2 supplies all of Unit-2 (except 21 4kV bus) and 14 4kV bus. Either P-i13000 iscapable of supplying all loads on both Units.February 2016 74 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Annex.... V .............. B i I There are five onsite AC power sources:* 1A DG for bus11* 1B DG for busl14* 2A DG for bus 21* 2B DG for bus 24* 00 DG may be aiigned to any vital 4kV bus on either unit.The fifteen-minute interval was selected as a threshold to exclude transient power losses. Ifmultiple sources fail to energize the unit safety-related buses within 15 minutes, an Unusual Eventis declared under this EAL. The subsequent loss of the single remaining power source escalatesthe event to an Alert under EAL CA1 .1.CCNPP Basis Reference(s):1. UFSAR Section 8 and Figure 8-12. Technical Specifications LCO 3.8.2 AC Sources-Shutdown3. Technical Specifications LCO 3.8.10 Distribution Systems-Shutdown4. 0I-21lA-1 1A Diesel Generator5. OI-21A-2 2A Diesel Generator6. OI-21B-1 lB Diesel Generator7. OI-21B-2 2B Diesel Generator8. 0I-21C 00 Diesel Generator9. STP-O-90 AC Sources and On-site Power Distribution Systems 7 Day Operability Verification10. AOP-71 Loss of 4kV, 480 Volt, or 208/120 Volt Instrument Bus Power11. AOP-3F Loss of Off-site Power While in MODES 3, 4, 5, or 612. EOP-2 Loss of Off-site Power13. NEI 99-01 CU3February 201675EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Su bcategory:C -Cold Shutdown / Refueling System Malfunction1 -Loss of AC PowerInitiating Condition: Loss of all offsite and all onsite AC power to 4kV vital buses for >15 min.EAL:CA1.1 AlertLoss of all offsite and all onsite AC power, Table C-I, to 4kV vital buses 11(21) and 14(24)for _> 15 min. (Note 4)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time.Table C-I AC Power Sources* 1(2)A DGa 1(2)B DG* 0C DG, if aligned* 500kV transmission line 5051* 500kV transmission line 5052*41 500kV transmission line 5072o

• SMECO line, if aligned* A credited 500kV line must have anindependent 13kV service transformerMode Applicability:5 -Cold Shutdown, 6 -Refuel, D -DefueledBasis:GenericLoss of all AC power compromises all plant safety systems requiring electric power including RHR,ECCS, Containment Heat Removal, Spent Fuel Heat Removal and the Ultimate Heat Sink.The event can be classified as an Alert when in cold shutdown, refuel, or defueled mode becauseof the significantly reduced decay heat and lower temperature and pressure, increasing the time torestore one of the emergency busses, relative to that specified for the Site Area Emergency EAL.Escalating to Site Area Emergency, if appropriate, is by EALs in Category R.February 201676EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearFifteen minutes was selected as a threshold to exclude transient or momentary power losses.Plant-SpoecificThe CCNPP vital buses are 4kV buses 11 (21) and 14(24). There are five offsite power sourcesavailable to these buses:* Three 500kV transmission lines (Lines 5051, 5052, and 5072) supply offsite power to the500kV switchyard via the transmission network.*One 69kV/1 3kV Southern Maryland Electric Cooperative (SMECO) line may be manuallyconnected to either vital 13kV bus and then to the 4kV vital buses. Under certainoperational conditions, 13kV bus(es) may be receiving power from SMECO or may bequickiy connected to the SMECO tie-line. The SMECO line is not used to carry loads for anoperating unit and may provide power to no more than two 4kV vital buses simultaneously.*If a fault affects only one unit, power may be obtained from the 500kV supply of theunaffected unit through a single 13 kV transformer. This is considered an offsite AC powersource available to the affected unit.In-house power is fed back from the 500kV ring bus through 2 13kV transformers (designated P-13000-1 and P-i13000-2). Normally P-i13000-1 supplies all of Unit -I (except 14 4kV bus) and 214kV bus. P-I13000-2 supplies all of Unit-2 (except 21 4kV bus) and 14 4kV bus. Either P-13000 iscapable of supplying all loads on both Units.There are five onsite AC power sources:* 1A DG for bus11* 1B DGforbusl14* 2A DG for bus 21* 2B DG for bus 24* OC DG may be aligned to any vital 4kV bus on either unit.Based on operational experience, if the SMECO line or the OC DG is not already aligned, thesecannot be considered available/capable of supplying the bus due to the time it will take to alignthem. In any case, if this cannot be accomplished within 15 minutes, they are not available and anAlert must be declared.February 2016 77 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearConsideration should be given to operable loads necessary to remove decay heat or provideReactor Vessel makeup capability when evaluating loss of all AC power to vital buses. Eventhough an essential bus may be energized, if necessary loads (i.e., loads that if lost would inhibitdecay heat removal capability or Reactor Vessel makeup capability) are not operable on theenergized bus then the bus should not be considered operable.The fifteen-minute interval was selected as a threshold to exclude transient power losses. If the 0CDG is available but is not powering a vital bus within 15 minutes, the EAL remains applicable.This EAL is the cold condition equivalent of the hot condition loss of all AC power EAL SS1.1.CCNPP Basis Reference(s):1. UFSAR Section 8 and Figure 8-12. Technical Specifications LCO 3.8.2 AC Sources-Shutdown3. Technical Specifications LCO 3.8.10 Distribution Systems-Shutdown4. 0I-21lA-1 IA Diesel Generator5. Ol-21A-2 2A Diesel Generator6. Ol-21B-1 lB Diesel Generator7. 0I-21 B-2 2B Diesel Generator8. 0I-21C 00 Diesel Generator9. STP-O-90 AC Sources and On-site Power Distribution Systems 7 Day Operability Verification10. AOP-71 Loss of 4kV, 480 Volt, or 208/120 Volt Instrument Bus Power11. AOP-3F Loss of Off-site Power While in MODES 3, 4, 5, or 612. EOP-2 Loss of Off-site Power13. EOP-7 Station Blackout14. EOP-8 Functional Recovery15. NEI 99-01 CA3February 2016 78 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: C -Cold Shutdown / Refueling System MalfunctionSubcategory: 2 -Loss of DC PowerInitiating Condition: Loss of required DC power for> 15 min.EAL:CU2.1 Unusual Event< 105 VDC for_ 15min. on the 125 VDC buses (11, 12, 21 or 22) that are required tomonitor and control the removal of decay heat (Note 4)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time.Mode Applicability:5 -Cold Shutdown, 6 -RefuelBasis:GenericThe purpose of this EAL is to recognize a loss of DC power compromising the ability to monitor andcontrol the removal of decay heat during Cold Shutdown or Refueling operations.Fifteen minutes was selected as a threshold to exclude transient or momentary power losses.Plant-Sp~ecificThe 125 VDC vital system is divided into four independent and isolated channels. Each channelconsists of one battery, two battery chargers, one DC bus, multiple DC unit control panels, and twoinverters. Each inverter has an associated vital AC distribution panel board. Power to the DC bus,DC unit control panels, and inverters is supplied by the station batteries and/or the batterychargers. Each battery charger is fully rated and can recharge a discharged battery while at thesame time supplying the steady state power requirements of the system. A reserve 125 VDCsystem for the plant is completely independent and isolated from all four separation groups, yet iscapable of replacing any of the 125 VDC batteries. This system consists of one battery, one batterycharger, and the associated DC switching equipment. Only the battery may be transferred forreplacement duty.The safety-related station batteries have been sized to carry their expected shutdown loadsfollowing a plant trip/LOCA and loss of offsite power or following a station blackout without batteryterminal voltage falling below 105 volts. The fifteen-minute interval was selected as a threshold toFebruary 2016 79 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclearexclude transient or momentary power losses. The loss of the 1A Diesel Generator 125 VDC bus14 or 00 Diesel Generator bus 16 does not constitute an entry condition for this EAL.Maintenance on a DC bus may be performed periodically during shutdown conditions. The"required" 125 VDC buses signifies the minimum allowed by Technical Specifications for the modeof operation (Refer to Technical Specification 3.8.10 for required 1 25V DC Buses). If loss of the"required" bus results in the inability to maintain cold shutdown, consideration should be given toescalation to an Alert under EAL CA4. 1.CCNPP Basis Reference(s):1. UFSAR Section 8.4.3 and Figure 8.92. EOP-0 Post-Trip Immediate Actions3. EOP-2 Loss of Off-Site Power, Section V4. AOP-7J Loss of 120 Volt Vital AC or 125 Volt Vital DC Power5. Technical Specifications Bases 3.8.106. NEI 99-01 CU7February 201680EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: C -Cold Shutdown I Refueling System MalfunctionSubcategory: 3 -RCS LevelInitiating Condition: RCS leakageEAL:CU3.1 Unusual EventRCS leakage results in the inability to maintain or restore EITHER of the following for>_15mrai. (Note 4):Pressurizer level > 101 in.ORRCS level within the target band established by procedure (when the level band wasestablished below 101 in.)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable timeMode Applicability:5 -Cold ShutdownBasis:GenericThis EAL is considered to be a potential degradation of the level of safety of the plant. The inabilityto maintain or restore level is indicative of loss of RCS inventory.Relief valve normal operation should be excluded from this EAL. However, a relief valve thatoperates and fails to close per design should be considered applicable to this EAL if the relief valvecannot be isolated.Prolonged loss of RCS inventory may result in escalation to the Alert emergency classification levelvia either EAL CA4.1 or EAL CA3.1.Plant-SpecificWhen pressurizer level drops to 101 in., pressurizer heaters are deenergized. This condition issignaled by annunciator 1006-ALM Window E-35, PZR HTR CUTOFF.In Cold Shutdown mode, pressurizer level may be intentionally lowered below the heater cutoffsetpoint (e.g., in preparation to detension the reactor vessel head, etc.). For such evolutions, thisEAL is applicable if RCS level cannot be restored and maintained within the prescribed target bandspecified by procedure.February 2016 81 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCCNPP Basis Reference(s):1. 1 C06-ALM Window E-35, PZR HTR CUTOFF2. AOP-2, Excessive Reactor Coolant Leakage3. UFSAR 7.4.44. NEI 99-01 CU1February 201682EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryAnncwvvI::ln n Nuna-Il~rk Category:Subcategory:C -Cold Shutdown / Refueling System Malfunction3 -RCS LevelInitiating Condition: RCS LeakageEAL:CU3.2 Unusual EventUNPLANNED RCS level drop below EITHER of the following for - 15 min. (Note 4):Reactor Vessel flange (44 ft) (when the level band was established above the flange)ORTarget band (when the level band was established below the flange)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable timeMode Applicability:6 -RefuelBasis:GenericThis EAL is a precursor of more serious conditions and considered to be a potential degradation ofthe level of safety of the plant.Refueling evolutions that decrease RCS water level below the Reactor Vessel flange are carefullyplanned and procedurally controlled. An unplanned event that results in water level decreasingbelow the Reactor Vessel flange, or below the planned RCS water level for the given evolution (ifthe planned RCS water level is already below the Reactor Vessel flange), warrants declaration of aUE due to the reduced ROS inventory that is available to keep the core covered.The allowance of 15 minutes was chosen because it is reasonable to assume that level can berestored within this time frame using one or more of the redundant means of refill that should beavailable. If level cannot be restored in this time frame then it may indicate a more seriouscondition exists.Continued loss of RCS Inventory will result in escalation to the Alert emergency classification levelvia either EAL CA4.1 or EAL CA3.1.This EAL involves a decrease in RCS level below the top of the Reactor Vessel flange thatcontinues for 15 minutes due to an unplanned event. This EAL is not applicable to decreases inflooded reactor cavity level, which is addressed by EAL RU2.1, until such time as the leveldecreases to the level of the vessel flange.February 201683EP-AA-1 011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearPlant-SpecificThe Reactor Vessel flange level is at 44 ft (43.97 ft) Refueling Pool level (ref. 2). RCS elevationsand level indication capabilities are illustrated in Attachment 15 of AOP-3B (ref. 2).Figure C-1 illustrates the RCS levels associated with Category C EALs.This EAL involves a lowering in RCS level below the top of the Reactor Vessel flange, or theinability to maintain water level above the intended level when level is being intentionallymaintained below the flange, that continues for fifteen minutes due to an unplanned event. ThisEAL is not applicable to drops in flooded refueling pool level (covered by lowering spent fuel poolwater level in EAL RU2.1) until such time as the level lowers to the level of the vessel flange. Iflevel continues to lower and reaches the bottom of the RCS Hot Leg (35.58 ft), escalation to theAlert level under EAL CA3.1 would be appropriate. If the level lowering is accompanied by RCSheatup, escalation to the Alert level under EAL CA4.1 may also be appropriate.In Cold Shutdown mode, the RCS will normally be intact and standard RCS inventory and levelmonitoring means are available. In the Refuel mode, the RCS is not intact and Reactor Vessellevel and inventory are monitored by different means. In the Refuel mode, normal means of coretemperature indication and RCS level indication may not be available. Redundant means ofReactor Vessel level indication will normally be installed (including the ability to monitor levelvisually) to assure that the ability to monitor level will not be interrupted. Reactor Vessel water levelis normally monitored using the following instruments:* Refueling Pool Level LI-4140* RCS Level Narrow Range LI-4138* RCS Level Wide Range LI-4139* Local refueling level indicator (LG-4139 and tygon tubing)* Reactor Vessel Level Monitoring System (RVLMS)If RCS water level will be below the bottom of the Pressurizer (48.5 ft el.), IM installs and calibratesthe Refueling Level Cart in the Control Room and places the RCS Wide Range Level MonitoringSystem in service (LI-41 39). The Wide Range Level High/Low alarms (LAH/L-4139) and NarrowRange Level High/Low alarms (LAH/L-41 38) are set above/below the target RCS level. As waterlevel is changed, the alarms are reset every two feet. Table 1 of OP-7, Shutdown Operations,provides a cross-reference of Refueling Pool level and RVLMS alarm lights to various plantcomponent elevations.February 2016 84 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearDefinitions:UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.CCNPP Basis Reference(s):1. AOP-2, Excessive Reactor Coolant Leakage2. AOP-3B, Abnormal Shutdown Cooling Conditions3. OP-7 Shutdown Operations4. NEI 99-01 CU2Figure C-I: RCS Levels Thresholds (ref. 2)February 201685EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:C -Cold Shutdown / Refueling System Malfunction3 -RCS LevelInitiating Condition: RCS LeakageEAL:CU3.3 Unusual EventRCS level cannot be monitored with a loss of RCS inventory as indicated by anunexplained level rise in ANY Table C-2 sump / tank attributable to RCS leakageTable C-2 RCS Leakage Indications* Containment sump* Auxiliary Building sumps* Miscellaneous Waste System Tanks* RWT* RC Waste System TankMode Applicability:6 -RefuelBasis:GenericThis EAL is a precursor of more serious conditions and considered to be a potential degradation ofthe level of safety of the plant.Refueling evolutions that decrease RCS water level below the Reactor Vessel flange are carefullyplanned and procedurally controlled. An UNPLANNED event that results in water level decreasingbelow the Reactor Vessel flange, or below the planned RCS water level for the given evolution (ifthe planned RCS water level is already below the Reactor Vessel flange), warrants declaration of aUE due to the reduced ROS inventory that is available to keep the core covered.Continued loss of ROS Inventory will result in escalation to the Alert emergency classification levelvia either EAL CA3.1 or EAL CA4.1.February 201686EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearThis EAL addresses conditions in the refueling mode when normal means of core temperatureindication and RCS level indication may not be available. Redundant means of RCS levelindication will normally be installed (including the ability to monitor level visually) to assure that theability to monitor level will not be interrupted. However, if all level indication were to be lost during aloss of RCS inventory event, the operators would need to determine that RCS inventory loss wasoccurring by observing sump and tank level changes. Sump and tank level increases must beevaluated against other potential sources of leakage such as cooling water sources inside theContainment to ensure they are indicative of RCS leakage.Plant-SpecificIn this EAL, all level indication would be unavailable and, the Reactor Vessel inventory loss mustbe detected by Containment sump, Auxiliary Building sum ps, Miscellaneous Waste System Tanks,or RWVT level changes. AOP-2A-I (2), Excessive Reactor Coolant Leakage, provides direction fordetermining RCS leakage for off normal events and for operations troubleshooting. ContainmentSump narrow range level instrumentation (LI-4144/4145) on 1C08 (2008) and 1009 (2CO9)indicate level in the Containment Emergency Sump and can be trended prior to receiving theContainment Sump Level Hi alarm. Sump and tank level increases must be evaluated againstother potential sources of leakage such as cooling water sources inside the Containment to ensurethey are indicative of RCS leakage.Definitions:UnisolableA breach or leak that cannot be promptly isolated.CCNPP Basis Reference(s):1. AOP-2A Excessive Reactor Coolant Leakage2. STP 0-27-1(2) RCS Leakage Evaluation3. NEI 99-01 CU2February 2016 87 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:C -Cold Shutdown I Refueling System Malfunction3 -RCS LevelInitiating Condition: Loss of RCS inventoryEAL:CA3.1 AlertLoss of inventory as indicated by RCS water level < 35.6 ft (29 in. 6th alarm on RVLMS)ORRCS level cannot be monitored for >_ 15 min. with a loss of RCS inventory as indicated byan unexplained level rise in ANY Table C-2 sump I tank attributable to RCS leakage(Note 4)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time.Table C-2 RCS Leakage Indications* Containment sump* Auxiliary Building sumps* Miscellaneous Waste System Tanks* RWT* RC Waste System TankMode Applicability:5 -Cold Shutdown, 6 -RefuelBasis:GenericThis EAL serves as a precursor to a loss of ability to adequately cool the fuel. The magnitude ofthis loss of water indicates that makeup systems have not been effective and may not be capableof preventing further RCS level decrease and potential core uncovery. This condition will result in aminimum emergency classification level of an Alert.The inability to restore and maintain level after reaching this setpoint would be indicative of afailure of the RCS barrier.If RCS level continues to lower then escalation to Site Area Emergency will be via EAL 0S3.1, EALCS3.2 or EAL CS3.3.February 201688EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearPlant-SpiecificFigure C-I illustrates the RCS levels associated with Category C EALs.When RCS water level lowers to 35.58 ft (rounded to 35.6 ft), the bottom of the RCS hot leg isuncovered. This level can be monitored by:* Refueling Pool Level LI-4140* RCS Level Narrow Range LI-4138* RCS Level Wide Range LI-41 39* Local refueling level indicator (LG-4139 and tygon tubing)* RVLMS (6th RVLMS Alarm [29 in.1) corresponds to 35.58 ftThis EAL serves as a precursor to a loss of ability to adequately cool the fuel. The magnitude ofthis loss of water indicates makeup systems have not been effective and may not be capable ofpreventing further RCS or Reactor Vessel level lowering and potential core uncovery. The bottomof the hot leg is the level equal to the bottom of the Reactor Vessel loop penetration, not the lowpoint of the loop. This level was chosen because remote RCS level indication may be lost and lossof suction to decay heat removal systems has occurred. The inability to restore and maintain levelafter reaching this setpoint infers a failure of the RCS barrier.In Cold Shutdown, the decay heat available to raise RCS temperature during a loss of inventory orheat removal event may be significantly greater than in the Refuel mode. Entry into Cold Shutdownmode may be attained within hours of operating at power or hours after refueling is completed.Entry into the Refuel mode may not occur for many hours after the reactor has been shutdown.Thus, the heatup and the threat to damaging the fuel clad may be lower for events that occur in theRefuel mode with irradiated fuel in the Reactor Vessel. Note that the heatup threat could be lowerfor Cold Shutdown conditions if the entry into Cold Shutdown was following a refueling.In Cold Shutdown mode, the RCS will normally be intact and standard RCS inventory and levelmonitoring means are available. In the Refuel mode, the RCS is not intact and Reactor Vessellevel and inventory are monitored by different means. In the Refuel mode, normal means of coretemperature indication and RCS level indication may not be available. Redundant means ofReactor Vessel level indication will normally be installed (including the ability to monitor levelvisually) to assure that the ability to monitor level will not be interrupted.In the second condition of this EAL, all level indication would be unavailable and, the ReactorVessel/RCS inventory loss must be detected by Containment sump, Auxiliary Building sumps,February 2016 89 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearMiscellaneous Waste System Tanks, or RWT level changes. AOP-2A-I (2), Excessive ReactorCoolant Leakage, provides direction for determining RCS leakage for off normal events and foroperations troubleshooting. Containment Sump narrow range level instrumentation (LI-4144/4145)on 1C08(2C08) and lC09(2CO9) indicate level in the Containment Emergency Sump and can betrended prior to receiving the Containment Sump Level Hi alarm. Sump level increases must beevaluated against other potential sources of leakage such as cooling water sources inside theContainment to ensure they are indicative of RCS leakage.The 15-minute interval for the loss of level indication was chosen because it is half of the Site AreaEmergency EAL duration. The interval allows this EAL to be an effective precursor to the Site AreaEmergency EAL CS3.3. Therefore this EAL meets the definition for an Alert emergency.Definitions:UnisolableA breach or leak that cannot be promptly isolated.CCNPP Basis Reference(s):1. OP-7 Shutdown Operations2. AOP-2A Excessive Reactor Coolant Leakage3. AOP-3B, Abnormal Shutdown Cooling Conditions4. STP 0-27-1(2) RCS Leakage Evaluation5. NEI 99-01 CA1February 201690EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearFigure C-I: RCS Levels Thresholds (ref. 2)February 201691EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: C -Cold Shutdown / Refueling System MalfunctionSubcategory: 3 -RCS LevelInitiating Condition: Loss of RCS inventory affecting core decay heat removal capabilityEAL:CS3.1 Site Area EmergencyWith CONTAINMENT CLOSURE not established, RCS level < 34.7 ft (19 in. 7th alarm onRVLMS)Mode Applicability:5 -Cold Shutdown, 6 -RefuelBasis:GenericUnder the conditions specified by this EAL, continued decrease in RCS level is indicative of a lossof inventory control. Inventory loss may be due to an RCS breach, pressure boundary leakage, orcontinued boiling in the RCS. Thus, declaration of a Site Area Emergency is warranted.Escalation to a General Emergency is via EAL CG3.1, EAL CG3.2, RG1.1, RG1.2 or RG1.3.Plant-SpecificFigure C-i illustrates the RCS levels associated with Category C EALs.This level can be monitored by:* Refueling Pool Level LI-4140* RCS Level Narrow Range LI-4138* RCS Level Wide Range LI-41 39* Local refueling level indicator (LG-4139 and tygon tubing)* RVLMS (7th RVLMS Alarm) corresponds to 34.74 ftWhen Reactor Vessel water level drops to 34.74 ft el. (rounded to 34.7 ft), level is ten inches belowthe bottom of the RCS hot leg vessel penetration.Under the conditions specified in this EAL, continued lowering of RCS water level is indicative of aloss of inventory control. Inventory loss may be due to a vessel breach, RCS pressure boundaryleakage or continued boiling in the Reactor Vessel. The magnitude of this loss of water indicatesthat makeup systems have not been effective and may not be capable of preventing further RCS orReactor Vessel water level lowering and core uncovery. The inability to restore and maintain levelFebruary 2016 92 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclearafter reaching this setpoint infers a failure of the RCS barrier and potential loss of the Fuel Cladbarrier.Containment Closure is the action or condition that ensures Containment and its associatedsystems, structures or components, as listed in STP O-55A, provide a functional barrier to fissionproduct release. Containment closure is initiated by the Shift Manager if plant conditions changethat could raise the risk of a fission product release as a result of a loss of decay heat removal.Containment closure requires that, upon a loss of decay heat removal, any open penetration mustbe closed or capable of being closed prior to RCS bulk boiling.Definitions:Containment ClosureThe site specific procedurally defined actions taken to secure Containment and its associatedstructures, systems, and components as a functional barrier to fission product release underexisting plant conditions. As applied to CCNPP, Containment Closure is the action or conditionthat ensures Containment and its associated systems, structures or components (SSC), aslisted in STP O-55A, provide a functional barrier to fission product release.CCNPP Basis Reference(s):1. UFSAR 7.5.92. OP-7 Shutdown Operations3. AOP-3B, Abnormal Shutdown Cooling Conditions4. ERPIP-601 Severe Accident Management Initial Diagnosis5. NO-i-i114 Containment Closure6. STP O-55A-1 (2) Containment Closure Verification7. NEI 99-01 CS1February 201693EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearFigure C-I: RCS Levels Thresholds (ref. 2)February 201694EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: C -Cold Shutdown / Refueling System MalfunctionSubcategory: 3 -RCS LevelInitiating Condition: Loss of RCS inventory affecting core decay heat removal capabilityEAL:CS3.2 Site Area EmergencyWith CONTAINMENT CLOSURE established, RCS level < 32.9 ft (10 in. alarm on RVLMS(Note 6))Note 6: The lowest RVLMS indication is the 10 In. alarm, which is 10 in. above top of active fuel. Therefore, thisindicator should only be used when a valid RFP/RCS level indication is not available.Mode Applicability:5 -Cold Shutdown, 6 -RefuelingBasis:GenericUnder the conditions specified by this EAL, continued decrease in RCS level is indicative of a lossof inventory control. Inventory loss may be due to an RCS breach, pressure boundary leakage, orcontinued boiling in the RPV. Thus, declaration of a Site Area Emergency is warranted.Escalation to a General Emergency is via EAL CG3.1, EAL CG3.2, RG1.1, RG1.2 or RG1.3.Plant-SpecificThis level can be monitored by:* Refueling Pool Level LI-4140* RCS Level Narrow Range LI-4138* RCS Level Wide Range LI-4139* Local refueling level indicator (LG-4139 and tygon tubing)* RVLMS (7th RVLMS Alarm) corresponds to 34.74 ftFigure C-i illustrates the RCS levels associated with Category C EALs.When Reactor Vessel/RCS water level drops to 32.9 ft el., core uncovery is about to occur. Thislevel is below the lowest indicated hot leg level. The closest RVLMS indication is the 10 in. alarm.Therefore, this indicator should only be used when a valid RFP/RCS level indication is notavailable.February 2016 95 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearUnder the conditions specified in this EAL, continued lowering of RCS water level is indicative of aloss of inventory control. Inventory loss may be due to a vessel breach, RCS pressure boundaryleakage or continued boiling in the Reactor Vessel. The magnitude of this loss of water indicatesthat makeup systems have not been effective and may not be capable of preventing further RCS orReactor Vessel water level lowering and core uncovery. The inability to restore and maintain levelafter reaching this setpoint infers a failure of the RCS barrier and potential loss of the Fuel Cladbarrier.Containment Closure is the action or condition that ensures Containment and its associatedsystems, structures or components, as listed in STP O-55A, provide a functional barrier to fissionproduct release. Containment closure is initiated by the Shift Manager if plant conditions changethat could raise the risk of a fission product release as a result of a loss of decay heat removal.Containment closure requires that, upon a loss of decay heat removal, any open penetration mustbe closed or capable of being closed prior to RCS bulk boiling.Definitions:Containment ClosureThe site specific procedurally defined actions taken to secure Containment and its associatedstructures, systems, and components as a functional barrier to fission product release underexisting plant conditions. As applied to CCNPP, Containment Closure is the action or conditionthat ensures Containment and its associated systems, structures or components (SSC), aslisted in STP O-55A, provide a functional barrier to fission product release.CCNPP Basis Reference(s):1. UFSAR 7.5.92. OP-7 Shutdown Operations3. AOP-3B, Abnormal Shutdown Cooling Conditions4. ERPIP-601 Severe Accident Management Initial Diagnosis5. NO-i-i114 Containment Closure6. STP O-55A-1 (2) Containment Closure Verification7. NEI 99-01 CS1February 2016 96 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexIExelon NuclearFigure C-I: RCS Levels Thresholds (ref. 2)February 201697EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory: C -Cold Shutdown / Refueling System MalfunctionSubcategory: 3 -RCS LevelInitiating Condition: Loss of RCS inventory affecting core decay heat removal capabilityEAL:CS3.3 Site Area EmergencyRCS level cannot be monitored for _ 30 main.with a loss of RCS inventory as indicated byANY of the following (Note 4):* Containment radiation > 6 R/hr* Erratic WRNI indication* Unexplained level rise in ANY Table C-2 sumnp I tank attributable to RCS leakageNote 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time.Table C-2 RCS Leakage Indications* Containment sump* Auxiliary Building sumps* Miscellaneous Waste System Tanks* RWT* RC Waste System TankMode Applicability:5 -Cold Shutdown, 6 -RefuelBasis:GenericUnder the conditions specified by this EAL, continued decrease in RCS level is indicative of a lossof inventory control. Inventory loss may be due to an RCS breach, pressure boundary leakage, orcontinued boiling in the RCS. Thus, declaration of a Site Area Emergency is warranted.Escalation to a General Emergency is via EAL CG3.1, EAL CG3.2, RG1.1, RG1.2 or RG1.3.The 30-minute duration allows sufficient time for actions to be performed to recover inventorycontrol equipment.As water level in the Reactor Vessel lowers, the dose rate above the core will increase. The doserate due to this core shine should result in site specific monitor indication and possible alarm.February 201698EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearPlant-SpecificIn Refuel or Cold Shutdown mode, normal RCS level indication (e.g., RVLMS) may be unavailablebut alternate means of level indication are normally installed (including visual observation) toassure that the ability to monitor level will not be interrupted. If all means of level monitoring are notavailable, however, the Reactor Vessel inventory loss may be detected by the following indirectmethods:*As water level in the Reactor Vessel lowers, the dose rate above the core will rise. Thedose rate due to this core shine should result in on-scale Containment radiation monitorindication and possible alarm. Containment radiation is indicated on 1(2)-RI-5317 A&B.Typical Containment radiation readings at full power are 1 to 1.2 R/hr. The Containmentradiation monitors alarm at 6 R/hr. The 6 R/hr setpoint has been selected to beoperationally significant and above that expected under normal plant conditions while in theRefuel mode.*Post-TMI studies indicated that the installed nuclear instrumentation will operate erraticallywhen the core is uncovered and that source range monitors such as Wide Range NuclearInstrumentation JI-O01, -002, -003, -004 and the Shutdown Monitor can be used as a toolfor making such determinations. Figure C-2 shows the response of the source rangemonitor during the first few hours of the TMI-2 accident. The instrument reported anincreasing signal about 30 minutes into the accident. At this time, the reactor coolant pumpswere running and the core was adequately cooled as indicated by the core outletthermocouples. Hence, the increasing signal was the result of an increasing two-phase voidfraction in the reactor core and vessel downcomer and the reduced shielding that the two-phase mixture provides to the source range monitor. Per CCNPP core damage assessmentstudies, core uncovery may be indicated when incore Rhodium neutron detectors or excorenuclear instruments indicate an output with the reactor known to be shutdown.*If water level indication is unavailable, the RCS inventory loss may be detected by sump ortank level changes (Table C-2). Procedures provide instructions for calculating primarysystem leak rate by manual or computer-based water inventory balances. Sump/tank levelincreases must be evaluated against other potential sources of leakage such as coolingwater sources inside the Containment to ensure they are indicative of RCS leakage.February 2016 99 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryC.alvcrt CliffR AnnmeFva~Inn Nii~nlzrW Vm V mRm BY m IB mm m m Definitions:UnisolableA breach or leak that cannot be promptly isolated.CCNPP Basis Reference(s):1. UFSAR 7.5.22. 0I-35 Radiation Monitoring System3. 1C10-ALM ESFAS 14 Alarm Manual, J-044. TS-76.01 RMS Area Radiation (Containment High Range) -Operable5. ERPIP-601 Severe Accident Management Initial Diagnosis6. ERPIP 602 Severe Accident Management Verification of Diagnosis7. ERPIP-800 Core Damage Assessment8. ERPIP-801 Core Damage Assessment Using Containment Radiation Dose Rates9. OP-7 Shutdown Operations10. AOP-2A Excessive Reactor Coolant Leakage11. STP 0-27-1(2) ROS Leakage Evaluation12. NEI 99-01 CS1February 2016100EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearFigure C-2: Response of the TMI-2 Source Range MeasurementDuring the First Six Hours of the Accidentc~J1~0c'JV..(I)a)C0.L..0.C3I-a)a)E1=31-jo-.~I~.I-(s~p~eop 6Ol) puooes ,!ad s],uno.,February 2016101EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:C -Cold Shutdown I Refueling System Malfunction3 -RCS LevelInitiating Condition: Loss of RCS inventory affecting fuel clad integrity withContainment challengedEAL:CG3.1 General EmergencyRCS level < 32.9 ft (10 in. alarm on RVLMS, Note 6) for _> 30 min. (Note 4)ANDANY Containment Challenge Indication, Table C-3Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time.Note 6: The lowest RVLMS indication is the 10 in. alarm, which is 10 in. above top of active fuel. Therefore, thisindicator should only be used when a valid RFP/RCS level indication is not available.Table C-3 Containment Challenge Indications* CONTAINMENT CLOSURE not established* Hydrogen concentration in Containment--- 4%* UNPLANNED rise in Containment pressureMode Applicability:5 -Cold Shutdown, 6 -RefuelBasis:GenericThis EAL represents the inability to restore and maintain RCS level to above the top of active fuelwith Containment challenged. Fuel damage is probable if RCS level cannot be restored, asavailable decay heat will cause boiling, further reducing the RCS level. With the Containmentbreached or challenged then the potential for unmonitored fission product release to theenvironment is high. This represents a direct path for radioactive inventory to be released to theenvironment. This is consistent with the definition of a GE. The GE is declared on the occurrenceof the loss or imminent loss of function of all three barriers.A number of variables can have a significant impact on heat removal capability challenging the fuelclad barrier. Examples include: mid-loop, reduced level/flange level, head in place, cavity flooded,RCS venting strategy, decay heat removal system design, vortexing pre-disposition, steamgenerator U-tube drainingFebruary 2016102EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearAnalysis indicates that core damage may occur within an hour following continued core uncoverytherefore, 30 minutes was conservatively chosen.If Containment Closure is re-established prior to exceeding the 30 minute core uncovery time limitthen escalation to General Emergency would not occur.Plant-SpecificFigure C-I illustrates the RCS levels associated with Category C EALs.When Reactor Vessel water level drops to 32.90 ft el., core uncovery is about to occur. This level isbelow the lowest indicated hot leg level. The lowest RVLMS indication is the last alarm, which is at10. in. above top of active fuel.Under the conditions specified in this EAL, continued lowering of RCS water level is indicative of aloss of inventory control. Inventory loss may be due to a vessel breach, RCS pressure boundaryleakage or continued boiling in the Reactor Vessel. The magnitude of this loss of water indicatesthat makeup systems have not been effective and may not be capable of preventing further RCS orReactor Vessel water level lowering and core uncovery. The inability to restore and maintain levelafter reaching this setpoint infers a failure of the RCS barrier and potential loss of the Fuel Cladbarrier. Fuel damage is probable if core submergence cannot be restored as available decay heatwill cause boiling and further lowers the vessel level.Three indications are associated with Containment challenges:*Containment Closure is the action or condition that ensures Containment and its associatedsystems, structures or components, as listed in STP O-55A, provide a functional barrier tofission product release. Containment closure is initiated by the Shift Manager if plantconditions change that could raise the risk of a fission product release as a result of a lossof decay heat removal. Containment closure requires that, upon a loss of decay heatremoval, any open penetration must be closed or capable of being closed prior to RCS bulkboiling.*In the early stages of a core uncovery event, it is unlikely that hydrogen buildup due to acore uncovery could result in an explosive mixture of dissolved gases in Containment.However, Containment monitoring and/or sampling should be performed to verify thisassumption. A combustible mixture can be formed when hydrogen gas concentration in theContainment atmosphere is greater than 4% by volume.February 2016 103 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclear*Unplanned Containment pressure increases are not expected during Cold Shutdown orRefuel mode. The threshold is indicative of conditions challenging containment closure.Definitions:Containment ClosureThe site specific procedurally defined actions taken to secure Containment and its associatedstructures, systems, and components as a functional barrier to fission product release underexisting plant conditions. As applied to CCNPP, Containment Closure is the action or conditionthat ensures Containment and its associated systems, structures or components (SSC), aslisted in STP O-55A, provide a functional barrier to fission product release.UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.CCNPP Basis Reference(s):1. UFSAR 7.5.92. OP-7 Shutdown Operations3. ERPIP-601 Severe Accident Management Initial Diagnosis4. ERPIP-800 Core Damage Assessment5. NO-I1-114 Containment Closure6. STP O-55A-1 (2) Containment Closure Verification7. UFSAR 7.5.88. Technical Specifications Table 3.3.10-19. OI-41A Hydrogen Recombiners10.1ICI0-ALM ESFAS 14 Alarm Manual, J-0911. ERPIP-803 Core Damage Assessment Using Hydrogen12. EOP-8 Functional Recovery Procedure13. EOP-13.02 Hydrogen Concentration 4.0%14. UFSAR 1.2.515. UFSAR 5.1.116. Operating License Amendment No. 242/DPR-53 & 216/DPR-6917. NEI 99-01 CG1February 2016 104 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/Proprietary(.-Iwrf AnncvFwce~lnn Table C-I: RCS Levels Thresholds (ref. 2)February 2016105EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory: C -Cold Shutdown / Refueling System MalfunctionSubcategory: 3 -RCS LevelInitiating Condition: Loss of Reactor Vessel inventory affecting fuel clad integrity withContainment challengedEAL:CG3.2 General EmergencyRCS level cannot be monitored with core uncovery indicated by ANY of the following for _>30 mmi. (Note 4):* Containment radiation > 6 R/hr* Erratic WRNI indication* Unexplained level rise in ANY Table C-2 sump I tank attributable to RCS leakageANDANY Containment Challenge Indication, Table C-3Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable timeTable C-2 RCS Leakage Indications* Containment sump* Auxiliary Building sumps* Miscellaneous Waste System Tanks* RWT* RC Waste System TankTable C-3 Containment Challenge Indications* CONTAINMENT CLOSURE not established* Hydrogen concentration in Containment - 4%* UNPLANNED rise in Containment pressureMode Applicability:5 -Cold Shutdown, 6 -RefuelFebruary 2016106EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBasis:GenericThis EAL represents the inability to restore and maintain RCS level to above the top of active fuelwith Containment challenged. Fuel damage is probable if RCS level cannot be restored, asavailable decay heat will cause boiling, further reducing the RCS level. With the Containmentbreached or challenged then the potential for unmonitored fission product release to theenvironment is high. This represents a direct path for radioactive inventory to be released to theenvironment. This is consistent with the definition of a GE. The GE is declared on the occurrenceof the loss or imminent loss of function of all three barriers.A number of variables can have a significant impact on heat removal capability challenging the fuelclad barrier. Examples include: mid-loop, reduced level/flange level, head in place, cavity flooded,RCS venting strategy, decay heat removal system design, vortexing pre-disposition, steamgenerator U-tube drainingAnalysis indicates that core damage may occur within an hour following continued core uncoverytherefore, 30 minutes was conservatively chosen.If Containment Closure is re-established prior to exceeding the 30 minute core uncovery time limitthen escalation to General Emergency would not occur.Sump and tank level increases must be evaluated against other potential sources of leakage suchas cooling water sources inside the Containment to ensure they are indicative of RCS leakage.As water level in the RCS lowers, the dose rate above the core will increase. The dose rate due tothis core shine should result in site specific monitor indication and possible alarm.Post-TMI studies indicated that the installed nuclear instrumentation will operate erratically whenthe core is uncovered and that this should be used as a tool for making such determinations.Plant-SpecificIn Refuel or Cold Shutdown mode, normal RCS level indication (e.g., RVLMS) may be unavailablebut alternate means of level indication are normally installed (including visual observation) toassure that the ability to monitor level will not be interrupted. If all means of level monitoring are notavailable, however, the Reactor Vessel inventory loss may be detected by the following indirectmethods:*As water level in the Reactor Vessel lowers, the dose rate above the core will rise. Thedose rate due to this core shine should result in on-scale Containment radiation monitorindication and possible alarm. Containment radiation is indicated on 1(2)-RI-5317 A&B.Typical Containment radiation readings at full power are 1 to 1.2 R/hr. The Containmentradiation monitors alarm at 6 R/hr. The 6 R/hr setpoint has been selected to beFebruary 2016 107 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuc:learoperationally significant and above that expected under normal plant conditions while in theRefuel mode.*Post-TMI studies indicated that the installed nuclear instrumentation will operate erraticallywhen the core is uncovered and that source range monitors such as Wide Range NuclearInstrumentation JI-001, -002, -003, -004 and the Shutdown Monitor can be used as a toolfor making such determinations. Figure 0-2 shows the response of the source rangemonitor during the first few hours of the TMI1-2 accident. The instrument reported anincreasing signal about 30 minutes into the accident. At this time, the reactor coolant pumpswere running and the core was adequately cooled as indicated by the core outletthermocouples. Hence, the increasing signal was the result of an increasing two-phase voidfraction in the reactor core and vessel downcomer and the reduced shielding that the two-phase mixture provides to the source range monitor. Per CCNPP core damage assessmentstudies, core uncovery may be indicated when incore Rhodium neutron detectors or excorenuclear instruments indicate an output with the reactor known to be shutdown.*If water level indication is unavailable, the RCS inventory loss may be detected by sump ortank level changes (Table 0-2). Procedures provide instructions for calculating primarysystem leak rate by manual or computer-based water inventory balances. Sump/tank levelincreases must be evaluated against other potential sources of leakage such as coolingwater sources inside the Containment to ensure they are indicative of RCS leakage.Three indications are associated with Containment challenges:*Containment Closure is the action or condition that ensures Containment and its associatedsystems, structures or components, as listed in STP O-55A, provide a functional barrier tofission product release. Containment closure is initiated by the Shift Manager if plantconditions change that could raise the risk of a fission product release as a result of a lossof decay heat removal. Containment closure requires that, upon a loss of decay heatremoval, any open penetration must be closed or capable of being closed prior to RCS bulkboiling.*In the early stages of a core uncovery event, it is unlikely that hydrogen buildup due to acore uncovery could result in an explosive mixture of dissolved gases in Containment.However, Containment monitoring and/or sampling should be performed to verify thisFebruary 2016 108 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearassumption. A combustible mixture can be formed when hydrogen gas concentration in theContainment atmosphere is greater than 4% by volume.*Unplanned Containment pressure increases are not expected during cold shutdown orrefuel mode. The threshold is indicative of conditions challenging Containment closure.Definitions:Containment ClosureThe site specific procedurally defined actions taken to secure Containment and its associatedstructures, systems, and components as a functional barrier to fission product release underexisting plant conditions. As applied to CCNPP, Containment Closure is the action or conditionthat ensures Containment and its associated systems, structures or components (SSC), aslisted in STP O-55A, provide a functional barrier to fission product release.UnisolableA breach or leak that cannot be promptly isolated.UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.CCNPP Basis Reference(s):I. UFSAR 7.5.92. ERPIP-601 Severe Accident Management Initial Diagnosis3. ERPIP-800 Core Damage Assessment4. NO-I-I114 Containment Closure5. STP O-55A-I1(2) Containment Closure Verification6. UFSAR 7.5.87. Technical Specifications Table 3.3.10-I8. Ol-41A Hydrogen Recornbiners9. 1C1O-ALM ESFAS 14 Alarm Manual, J-0910. ERPIP-B03 Core Damage Assessment Using HydrogenII. EOP-8 Functional Recovery Procedure12. EOP-1 3.02 Hydrogen Concentration 4.0%13. UFSAR 1.2.514. UFSAR 5.1.115. Operating License Amendment No. 242/DPR-53 & 216/DPR-6916. NEI 99-01 CGIFebruary 2016 109 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexMm ...... ......... I=A YJI K 1* I Figure C-2: Response of the TMI-2 Source Range MeasurementDuring the First Six Hours of the Accident (ref. 10, 11)CjO000CBI-I-0E1=(0D(sepeoap 6oi) puooes Jied slunooEP-AA-1011 Addendum 3(Revision 1)February 2016110 Exelon Confidential/ProprietaryC_,,h,-r$ r~liffQ Ann,-vI~vInn NulrIl2r5 Vlllltml Category:Subcategory:C -Cold Shutdown / Refueling System Malfunction4 -RCS TemperatureInitiating Condition: Unplanned loss of decay heat removal capabilityEAL:CU4.1 Unusual EventUNPLANNED event results in RCS temperature > 200°FMode Applicability:5 -Cold Shutdown, 6 -RefuelBasis:GenericThis EAL is a precursor of more serious conditions and, as a result, is considered to be a potentialdegradation of the level of safety of the plant. In cold shutdown the ability to remove decay heatrelies primarily on forced cooling flow. Operation of the systems that provide this forced coolingmay be jeopardized due to the unlikely loss of electrical power or RCS inventory. Since the RCSusually remains intact in the cold shutdown mode a large inventory of water is available to keep thecore covered.During refueling the level in the RCS will normally be maintained above the Reactor Vessel flange.Refueling evolutions that decrease water level below the Reactor Vessel flange are carefullyplanned and procedurally controlled. Loss of forced decaY heat removal at reduced inventory mayresult in more rapid increases in RCS temperatures depending on the time since shutdown.Normal means of core temperature indication and ROS level indication may not be available in therefueling mode. Redundant means of RCS level indication are therefore procedurally installed toassure that the ability to monitor level will not be interrupted. Escalation to Alert would be via EALCA3.1 based on an inventory loss or EAL CA4.1 based on exceeding its temperature duration orpressure criteria.Plant-SpecificSeveral instruments are capable of providing indication of RCS temperature with respect to theTechnical Specification cold shutdown temperature limit (200°F). These include TI-i112C and TI-1220 for forced circulation, CETs for natural circulation and TR-351 for SOC flow.Definitions:UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.February 2016111EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCCNPP Basis Reference(s):I. Technical Specifications Table 1.1-12. OP-7 Shutdown Operations3. OP-I Plant Startup from Cold Shutdown4. NEI 99-01 CU4February 2016112EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:S ubcateg ory:C -Cold Shutdown / Refueling System Malfunction4 -RCS TemperatureInitiating Condition: Unplanned loss of decay heat removal capabilityEAL:CU4.2 Unusual EventLoss of all RCS temperature and RCS level indication for _> 15 min. (Note 4)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable timeMode Applicability:5 -Cold Shutdown, 6 -RefuelBasis:GenericThis EAL is a precursor of more serious conditions and, as a result, is considered to be a potentialdegradation of the level of safety of the plant. In cold shutdown the ability to remove decay heatrelies primarily on forced cooling flow. Operation of the systems that provide this forced coolingmay be jeopardized due to the unlikely loss of electrical power or RCS inventory. Since the RCSusually remains intact in the cold shutdown mode a large inventory of water is available to keep thecore covered.During refueling the level in the RCS will normally be maintained above the Reactor Vessel flange.Refueling evolutions that decrease water level below the Reactor Vessel flange are carefullyplanned and procedurally controlled. Loss of forced decay heat removal at reduced inventory mayresult in more rapid increases in RCS temperatures depending on the time since shutdown.Normal means of core temperature indication and RCS level indication may not be available in therefueling mode. Redundant means of RCS level indication are therefore procedurally installed toassure that the ability to monitor level will not be interrupted. However, if all level and temperatureindication were to be lost in either the cold shutdown of refueling modes, this EAL would result indeclaration of a UE if both temperature and level indication cannot be restored within 15 minutesfrom the loss of both means of indication. Escalation to Alert would be via EAL CA3.1 based on aninventory loss or EAL CA4.1 based on exceeding its temperature criteria.February 2016113EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearPlant-SpecificReactor Vessel water level may be monitored using any of the following instruments:* Refueling Pool Level LE-4140* RCS Level Narrow Range LE-4138* RCS Level Wide Range LE-4139* Local refueling level indicator (LG-4139 and tygon tubing)* Reactor Vessel Level Monitoring System (RVLMS)If RCS water level will be below the bottom of the Pressurizer (48.5 ft el.), IM installs and calibratesthe Refueling Level Cart in the Control Room and places the RCS Wide Range Level MonitoringSystem in service (LE-41 39). The Wide Range Level High/Low alarms and Narrow Range LevelHigh/Low alarms are set above/below the target RCS level. Table I of OP-7, ShutdownOperations, provides a cross-reference of Refueling Pool level and RVLMS alarm lights to variousplant component elevations. If all RCS water level indication is lost during ROS drain down, OP-7requires the following:* Stop the RCS drain down and evaluate the reason for the loss of level indication.*When at least two remote and one local RCS level indicator have been restored and arereading within 0.5 ft of each other, continue RCS drain down. Allow 15 mai. for pressures toequalize. If level readings are not within 0.5 ft, call IM to investigate discrepancies.Several instruments are capable of providing indication of RCS temperature with respect to theTechnical Specification cold shutdown temperature limit (200°F). These include TI-I1I2C and TI-122C for forced circulation, CETs for natural circulation and TR-351 for SDC flow.CCNPP Basis Reference(s):1. Technical Specifications Table 1.1-12. OP-7 Shutdown Operations3. 01-il Post Accident Monitoring System Instrumentation4. OP-i Plant Startup from Cold Shutdown5. NEI 99-01 CU4February 2016 114 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:C -Cold Shutdown / Refueling System Malfunction4 -RCS TemperatureInitiating Condition: Inability to maintain plant in cold shutdownEAL:0A4.1 AlertAn UNPLANNED event results in EITHER:RCS temperature > 200°F for > Table C-4 durationORRCS pressure increase > 10 psi due to an UNPLANNED loss of decay heat removalcapability (this condition is not applicable in solid plant conditions)Table C-4 RCS Reheat Duration ThresholdsCONTAINMENTRCS Status CLSR tts DurationIntact AND not*reduced inventory NA6 mNot intact OR Established 20 min.*reduced inventory Not established 0 mai.* If an RCS heat removal system is in operation within this timeframe and RCS temperature is being reduced, the EAL is notapplicable.Mode Applicability:5 -Cold Shutdown, 6 -RefuelBasis:GenericThe RCS Reheat Duration Thresholds table addresses complete loss of functions required for corecooling for greater than 60 minutes during refuel and cold shutdown modes when RCS integrity isestablished. RCS integrity should be considered to be in place when the RCS pressure boundaryis in its normal condition for the cold~ shutdown mode of operation (e.g., no freeze seals or nozzledams). The status of CONTAINMENT CLOSURE in this condition is immaterial given that the RCSis providing a high pressure barrier to fission product release to the environment. The 60 minutetime frame should allow sufficient time to restore cooling without there being a substantialdegradation in plant safety.The RCS Reheat Duration Thresholds table also addresses the complete loss of functions requiredfor core cooling for greater than 20 minutes during refuel and cold shutdown modes whenFebruary 2016115EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearContainment Closure is established but RCS integrity is not established or RCS inventory isreduced (e.g., mid-loop operation in PWRs)]. [As discussed above, RCS integrity should beassumed to be in place when the RCS pressure boundary is in its normal condition for the coldshutdown mode of operation (e.g., no freeze seals or nozzle dams). The allowed 20 minute timeframe was included to allow operator action to restore the heat removal function, if possible. Theallowed time frame is consistent with the guidance provided by Generic Letter 88-17, "Loss ofDecay Heat Removal" (discussed later in this basis) and is believed to be conservative given that alow pressure Containment barrier to fission product release is established.Finally, complete loss of functions required for core cooling during refuel and cold shutdown modeswhen neither Containment Closure nor RCS integrity are established is addressed. RCS integrity isin place when the RCS pressure boundary is in its normal condition for the cold shutdown mode ofoperation (e.g., no freeze seals or nozzle dams). No delay time is allowed because the evaporatedreactor coolant that may be released into the Containment during this heatup condition could alsobe directly released to the environment.The note (*) indicates that this EAL is not applicable if actions are successful in restoring an RCSheat removal system to operation and RCS temperature is being reduced within the specified timeframe.The 10 psi pressure increase addresses situations where, due to high decay heat loads, the timeprovided to restore temperature control, should be less than 60 minutes. The RCS pressuresetpoint was chosen because it is the lowest pressure that the site can read on installed ControlBoard instrumentation that is equal to or greater than 10 psi.Escalation to Site Area Emergency would be via EAL CS3.1 should boiling result in significant RPVlevel loss leading to core uncovery.A loss of Technical Specification components alone is not intended to constitute an Alert. Thesame is true of a momentary unplanned excursion above the Technical Specification coldshutdown temperature limit when the heat removal function is available.The Emergency Director must remain alert to events or conditions that lead to the conclusion thatexceeding the EAL is imminent. If, in the judgment of the Emergency Director, an imminentsituation is at hand, the classification should be made as if the threshold has been exceeded.Plant-SpecificSeveral instruments are capable of providing indication of RCS temperature with respect to theTechnical Specification cold shutdown temperature limit (200°F). These include TI-i112C and TI-122C for forced circulation, CETs for natural circulation and TR-351 for SDC flow.Containment Closure is the action or condition that ensures Containment and its associatedsystems, structures or components, as listed in STP O-55A, provide a functional barrier to fissionproduct release. Containment closure is initiated by the Shift Manager if plant conditions changethat could raise the risk of a fission product release as a result of a loss of decay heat removal.February 2016 116 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearContainment closure requires, upon a loss of decay heat removal, any open penetration must beclosed or capable of being closed prior to RCS boiling."Reduced inventory" is the condition when the reactor vessel contains irradiated fuel assembliesand RCS water level is at or below 41 ft el.The pressure rise of greater than 10 psi infers an RCS temperature in excess of the TechnicalSpecification cold shutdown limit (200°F) for which this EAL would otherwise permit up to sixtyminutes to restore RCS cooling before declaration of an Alert (RCS intact). This EAL thereforecovers situations in which it is determined that, due to high decay heat loads, the time provided toreestablish temperature control should be less than sixty minutes (as indicated by significant RCSre-pressurization).Pressure indicators PI-103, P1-i103-1 and P1-105 are capable of measuring pressure changes of 10psi. Escalation to a Site Area Emergency would be under EAL CS3.1 should boiling result insignificant Reactor Vessel level loss leading to core uncovery.Definitions:Containment ClosureThe site specific procedurally defined actions taken to secure Containment and its associatedstructures, systems, and components as a functional barrier to fission product release underexisting plant conditions. As applied to CCNPP, Containment Closure is the action or conditionthat ensures Containment and its associated systems, structures or components (SSC), aslisted in STP O-55A, provide a functional barrier to fission product release.UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.CCNPP Basis Reference(s):1. Technical Specifications Table 1.1-12. NO-i-i114 Containment Closure3. STP O-55A-1 (2) Containment Closure Verification4. OP-7 Shutdown Operations5. OP-I Plant Startup from Cold Shutdown6. NEI 99-01 CA4February 2016 117 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:C -Cold Shutdown I Refueling System MalfunctionSubcategory: 5 -CommunicationsInitiating Condition: Loss of all onsite or offsite communications capabilitiesEAL:CU5.1 Unusual EventLoss of all Table C-5 onsite (internal) communication methods affecting the ability toperform routine operationsORLoss of all Table C-5 offsite (external) communication methods affecting the ability toperform offsite notifications to any agencyTable C-5 Communications SystemsOnsite OffsiteSystem (internal) (external)Commercial phone system X XPlant page system XFTS 2001 telephone system XCCNPP Radio System XSatellite Phone System XCellular Phone System X XMode Applicability:5 -Cold Shutdown, 6 -Refuel, D -DefueledBasis:GenericThe purpose of this EAL is to recognize a loss of communications capability that either defeats theplant operations staff ability to perform routine tasks necessary for plant operations or the ability tocommunicate issues with any off-site authorities. The loss of off-site communications ability isexpected to be significantly more comprehensive than the condition addressed by 10 CFR 50.72.The availability of one method of ordinary off-site communications is sufficient to inform federal,state, and local authorities of plant issues. This EAL is intended to be used only whenFebruary 2016118EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearextraordinary means (e.g., relaying of information from radio transmissions, individuals being sentto off-site locations, etc.) are being utilized to make communications possible.PIa nt-SpecificOnsite/offsite communications systems are listed in Table 0-2 (ref. 1, 2, 3).This EAL is the cold condition equivalent of the hot condition EAL SU6.1.CCNPP Basis Reference(s):1. UFSAR Section 7.82. Emergency Response Facility Directory & Communications Equipment Information3. NO-i1-113, Control of Radio Transmitter (PRT)4. NEI 99-01 CU6February 2016119EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: C -Cold Shutdown / Refueling System MalfunctionSubcategory: 6 -Inadvertent CriticalityInitiating Condition: Inadvertent criticalityEAL:0U6.1 Unusual EventAn UNPLANNED sustained positive startup rate observed on nuclear instrumentationMode Applicability:5 -Cold Shutdown, 6 -RefuelBasis:GenericThis EAL addresses criticality events that occur in Cold Shutdown or Refueling modes such as fuelmis-loading events and inadvertent dilution events. This EAL indicates a potential degradation ofthe level of safety of the plant, warranting aUE classification.Escalation would be by Emergency Director judgment.Plant-SpecificThe term "sustained" is used to allow exclusion of expected short-term positive startup rates fromplanned fuel bundle or control rod movements during core alteration. These short-term positivestartup rates are the result of the rise in neutron population due to subcritical multiplication.Definitions:UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.CCNPP Basis Reference(s):1. UFSAR Section 7.5.2.2.2. Technical Specifications 3.9.23. 1005-ALM Reactivity Control Alarm Manual, Window D-05, D-154. AOP-1A Inadvertent Boron Dilution5. NEI 99-01 CU8February 2016 120 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory H -. Hazards and Other Conditions Affecting Plant SafetyEAL Group: ANY (EALs in this category are applicable to anyplant condition, hot or cold.)Hazards are non-plant, system-related events that can directly or indirectly affect plant operation,reactor plant safety or personnel safety.The events of this category pertain to the following subcategories:1. Natural or Destructive PhenomenaNatural events include hurricanes, earthquakes or tornados that have potential to cause plantstructure or equipment damage of sufficient magnitude to threaten personnel or plant safety.Non-naturally occurring events that can cause damage to plant facilities and include aircraftcrashes, missile impacts, etc.2. Fire or ExplosionFires can pose significant hazards to personnel and reactor safety. Appropriate forclassification are fires within the site Protected Area or which may affect operability ofequipment needed for safe shutdown3. Hazardous GasNon-naturally occurring events that can cause damage to plant facilities and include toxic,asphyxiant, corrosive or flammable gas leaks.4. SecurityUnauthorized entry attempts into the Protected Area, bomb threats, sabotage attempts, andactual security compromises threatening loss of physical control of the plant.5. Control Room EvacuationEvents that are indicative of loss of Control Room habitability. If the Control Room must beevacuated, additional support for monitoring and controlling plant functions is necessarythrough the emergency response facilities.February 2016 121 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclear6. JudgmentThe EALs defined in other categories specify the predetermined symptoms or events that areindicative of emergency or potential emergency conditions and thus warrant classification.While these EALs have been developed to address the full spectrum of possible emergencyconditions which may warrant classification and subsequent implementation of the EmergencyPlan, a provision for classification of emergencies based on operator/management experienceand judgment is still necessary. The EALs of this category provide the Emergency Director thelatitude to classify emergency conditions consistent with the established classification criteriabased upon Emergency Director judgment.February 2016122EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 1 -Natural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting the Protected AreaEAL:HUI.1 Unusual EventSeismic event identified by ANY two of the following:* Seismic Monitor indicates a seismic event detected* Earthquake felt in plant* National Earthquake Information Center (Note 7)Note 7: The NEIC can be contacted by calling (303) 273-8500. Select option #1 and inform the analyst you wish toconfirm recent seismic activity in the vicinity of Calvert Cliffs Nuclear Power Plant. Provide the analyst with thefollowing CCNPP coordinates: 380 25' 39.7" north latitude, 760 26' 45" west longitude.Mode Applicability:AllBasis:GenericThis EAL is categorized on the basis of the occurrence of an event of sufficient magnitude to be ofconcern to plant operators.Damage may be caused to some portions of the site, but should not affect ability of safetyfunctions to operate.As defined in the EPRI-sponsored Guidelines for Nuclear Plant Response to an Earthquake, datedOctober 1989, a "felt earthquake" is: An earthquake of sufficient intensity such that: (a) thevibratory ground motion is felt at the nuclear plant site and recognized as an earthquake based ona consensus of Control Room operators on duty at the time, and (b) for plants with operableseismic instrumentation, the seismic switches of the plant are activated.The National Earthquake Center can confirm if an earthquake has occurred in the area of the plant.Plant-SpecificCCNPP seismic instrumentation actuates at 0.01g upon sensing any ground motion. Damage tosome portions of the site may occur as a result of the felt earthquake but it should not affect theability of safety functions to operate. This event escalates to an Alert under EAL HA1 .1 if theearthquake exceeds the Operating Basis Earthquake (OBE) magnitude of 0.08 g horizontal or0.053g vertical. (ref. 1)February 2016 123 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearThe National Earthquake Information Center (NEIC) can confirm seismic activity in the vicinity ofthe CCNPP. The NEIC can be contacted by calling (3013) 273-8500. Select option #1 and informthe analyst you wish to confirm recent seismic activity in the vicinity of Calvert Cliffs Nuclear PowerPlant. Provide the analyst with the following CCNPP coordinates: 330 25' 39.7" north latitude, 76026' 45" west longitude (ref. 3). Alternatively, information regarding the extent of a near-siteearthquake can be obtained by calling the University of Delaware (302) 821-1576.CCNPP Basis Reference(s):1. 0I-46 Seismic Measurement Equipment2. UFSAR Section 7.5.7 Seismic Instrumentation3. Calvert Cliffs ISFSI USAR Section 2.1.1 Site Location4. STPI M-260-0 Seismic Instrumentation Channel Check5. NE! 99-01 HU16. ECP-1 3-000653, Replace the existing five channel SMA-3 Seismic Montitor with a KinemetricsCondor Seismic Monitoring SystemFebruary 2016124EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 1 -Natural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting the Protected AreaEAL:HUI.2 Unusual EventTornado striking within PROTECTED AREA BOUNDARYORSustained high winds > 45 rn/sec (100 mph)Mode Applicability:AllBasis:GenericThis EAL is categorized on the basis of the occurrence of an event of sufficient magnitude to be ofconcern to plant operators.This EAL is based on a tornado striking (touching down) or high winds within the Protected Area.Escalation of this emergency classification level, if appropriate, would be based on visible damage,or by other in plant conditions, via EAL HA1 .2.Plant-SpecificAll Class 1 safe shutdown structures are designed for a wind velocity of 100 mph, 30 feet aboveground using a gust factor of 1.1. The meteorological tower 15-minute average wind speedreadings are the "sustained" wind speeds used to assess this EAL.Definitions:Protected AreaThe site specific area which normally encompasses all controlled areas within the securityProtected Area fence.CCNPP Basis Reference(s):1. ES-005 Civil and Structural Design Criteria2. CCIPEEE RAN 97-031 High Winds, Floods and Other External Events Analysis3. NEI 99-01 HU1February 2016 125 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 1 -Natural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting the Protected AreaEAL:HU1.3 .Unusual EventInternal flooding that has the potential to affect ANY SAFETY-RELATED STRUCTURE,SYSTEM, OR COMPONENT required by Technical Specifications for the current operatingmode in ANY Table H-I areaTable H-I Safe Shutdown Areas* Control Room* Containment* Auxiliary Building* Diesel Generator Rooms* Intake Structure* 1A/0C DG Buildings* RWT* RVVT Rooms* CST No. 12* FOSTNo. 21* Auxiliary Feed Pump RoomsMode Applicability:AllBasis:GenericThis EAL is categorized on the basis of the occurrence of an event of sufficient magnitude to be ofconcern to plant operators.This EAL addresses the effect of internal flooding caused by events such as component failures,equipment misalignment, or outage activity mishaps.Escalation of this emergency classification level, if appropriate, would be based visible damage viaEAL HAl1.3, or by other plant conditions.February 2016126EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearPlant-SpecificThis threshold addresses the affect of flooding caused by internal events such as componentfailures, Circulating, Saltwater, Component Cooling or Service Water line ruptures, equipmentmisalignment, fire suppression system actuation, and outage activity mishaps. The internal floodingareas contain systems that are:* Required for safe shutdown of the plant* Not designed to be wetted or submerged* Susceptible to internal flooding eventsFlooding as used in this EAL describes a condition where water is entering the room faster thaninstalled equipment is capable of removal, resulting in a rise of water level within the room.Classification of this EAL should not be delayed while corrective actions are being taken to isolatethe water source.Table H-i Safe Shutdown Areas include all SAFETY-RELATED STRUCTURE, SYSTEM, ORCOMPONENT needed for safe shutdown.Safety-Related Structures, Systems and Components (as defined in 1OCFR5O.2)Those structures, systems and components that are relied upon to remain functional duringand following design basis events to assure:(1) The integrity of the reactor coolant pressure boundary;(2) The capability to shut down the reactor and maintain it in a safe shutdown condition;(3) The capability to prevent or mitigate the consequences of accidents which could resultin potential offsite exposures.CCNPP Basis Reference(s):1. CCPRA RAN: 96-O24FLOOD Flood Rule Development2. CCPRA RAN: 98-062, Internal Flood Initiating Event Frequencies3. CCPRA RAN: 98-065, Flood Evaluations (Flood Queries)4. ICIO-ALM ESFAS 13 Alarm Manual, J-17, CC PP RM LVL HI5. 1C10-ALM ESFAS 13 Alarm Manual, J-18, SRW PP RM LVL HI6. 1C10-ALM ESFAS 13 Alarm Manual, J-22, CNDSR PIT LVL HI7. 1C10-ALM ESFAS 13 Alarm Manual, J-23, INTAKE SUMP STRUCTURE LVL HI8. 1C10-ALM ESFAS 13 Alarm Manual, J-24, INTAKE STRUCTURE CH TRIP9. Drawing 61502 Plant Property and Buildings10. UFSAR Section 5A.2 Classes of Structures, Systems, and Equipment11. NEI 99-01 HU1February 2016 127 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 1 -Natural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting the Protected AreaEAL:HUI.4 Unusual EventTurbine failure resulting in casing penetration or damage to turbine or generator sealsMode Applicability:AllBasis:GenericThese EALs are categorized on the basis of the occurrence of an event of sufficient magnitude tobe of concern to plant operators.This EAL addresses main turbine rotating component failures of sufficient magnitude to causeobservable damage to the turbine casing or to the seals of the turbine generator. Generator sealdamage observed after generator purge does not meet the intent of this EAL because it did notimpact normal operation of the plant.Of major concern is the potential for leakage of combustible fluids (lubricating oils) and gases(hydrogen cooling) to the plant environs. Actual FIRES and flammable gas build up areappropriately classified via EAL HU2.1 and EAL HU3.1.This EAL is consistent with the definition of a UE while maintaining the anticipatory nature desiredand recognizing the risk to non-safety related equipment.Escalation of this emergency classification level, if appropriate, would be to EAL HAl1.4 based ondamage done by PROJECTILES generated by the failure or in conjunction with a steam generatortube rupture. These latter events would be classified by the Category R EALs or Category F EALs.Plant-SpecificThe turbine generator stores large amounts of rotational kinetic energy in its rotor. In the unlikelyevent of a major mechanical failure, this energy may be transformed into both rotational andtranslational energy of rotor fragments. These fragments may impact the surrounding stationaryparts. If the energy-absorbing capability of these stationary turbine generator parts is insufficient,external projectiles will be released. These ejected projectiles may impact various plant structures,including those housing safety related equipment.February 2016 128 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearIn the event of projectile ejection, the probability of a strike on a plant region is a function of theenergy and direction of an ejected projectile and of the orientation of the turbine with respect to theplant region.Failure of turbine or generator seals may be indicated by a loss of seal oil pressure or loss ofcondenser vacuum (ref. 2, 3).CCNPP Basis Reference(s):1. AOP-7E Main Turbine Malfunction2. AOP-7G Loss of Condenser Vacuum3. 1 C02-ALM B-I10 Seal Oil Duff Press Lo4. NEI 99-01 HU1February 2016129EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 1 -Natural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting the Protected AreaEAL:HUI.5 Unusual EventBay water level > bottom of the traveling screen cover housing (+ 120 in. Mean Sea Level)ORBay water level < 13.6 ft below intake concrete level (- 43.2 in. Mean Sea Level)Mode Applicability:AllBasis:GenericThis EAL is categorized on the basis of the occurrence of an event of sufficient magnitude to be ofconcern to plant operators.This EAL addresses other site specific phenomena that can also be precursors of more seriousevents.Plant-SpecificThis threshold addresses high and low bay water level conditions that could be a precursor of moreserious events.Since the Intake Structure houses the saltwater pumps that are essential for safe shutdown ofCCNPP, the structure was designed as a Category I structure for seismic, tornado, and hurricaneconditions. The Intake Structure is also designed to protect the saltwater pump motors fromexternal flooding due to the maximum hypothetical hurricane tide and storm surges, including waveaction. The Intake Structure design loads and conditions are shown in UFSAR Table 5-7.l0 ft (+120 in.) Mean Sea Level (approximately bottom of the travelling screen cover) is the stillwater level used for the Intake Structural Analysis. This value was selected to be anticipatory to thedesign level of 18 ft Mean Sea Level (top of the travelling screen cover).The predicted extreme low tide elevation is -3.6 ft (-43.2 in.) Mean Sea Level. However, the planthas been designed for -4.0 ft Mean Sea Level and can continue to operate with an extreme lowFebruary 2016 130 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclearwater Elevation of -6.0 ft Mean Sea Level. The top of the saltwater pump intakes is at -9.5 ft MeanSea Level.Operations can measure water level from the intake concrete walking level to the Bay surface witha tape measure. This level is measured upstream (i.e., before) the trash racks. This EAL criterion ismet if the water is 13.6 ft below the intake concrete level by observation. This measurementrequires judgment because the Bay surface is not normally still.Radar probes (1-LIT-1100 & 2-LIT-2100) have been installed which provide local indication (1-LI-1100 & 2-LI-21 00) of Intake water level in inches relative to Mean Sea Level (ref. 4).CCNPP Basis Reference(s):1. UFSAR Sections 2.8.3.6 and 2.8.3.72. UFSAR Table 5-73. 1C10-ALM ESFAS 14 Alarm Manual, J-234. ECP-10-0002085. NEI 99-01 HU1February 2016131EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:S ubcateg ory:H -Hazards and Other Conditions Affecting Plant SafetyNatural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting Vital AreasEAL:HAl.1 AlertEITHER:Seismic Monitor indicates a seismic event > OBE (0.08 g horizontal or 0.053gvertical)ORControl Room indication of degraded performance of ANY SAFETY-RELATEDSTRUCTURE, SYSTEM, OR COMPONENTANDEarthquake confirmed by EITHER:Earthquake felt in plantORNational Earthquake Information Center (Note 7)Note 7: The NEIC can be contacted by calling (303) 273-8500. Select option #1 and inform the analyst you wish toconfirm recent seismic activity in the vicinity of Calvert Cliffs Nuclear Power Plant. Provide the analyst with thefollowing CCNPP coordinates: 380 25' 39.7" north latitude, 760 26' 45" west longitude.Mode Applicability:AllBasis:GenericThese EALs escalate from HUI.1 in that the occurrence of the event has resulted in damage to thesafety systems in those structures evidenced by Control Room indications of degraded systemresponse or performance. The occurrence of degraded system response is intended todiscriminate against lesser events. The initial report should not be interpreted as mandating alengthy damage assessment prior to classification. No attempt is made in this EAL to assess theactual magnitude of the damage. The significance here is not that a particular system or structurewas damaged, but rather, that the event was of sufficient magnitude to cause this degradation.Escalation of this emergency classification level, if appropriate, would be based on SystemMalfunction EALs.Seismic events of this magnitude can result in a VITAL AREA being subjected to forces beyonddesign limits, and thus damage may be assumed to have occurred to plant safety systems.February 2016132EP-AA-1 011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearThe National Earthquake Information Center can confirm if an earthquake has occurred in the areaof the plant.Plant-SpecificThis EAL is based on the UFSAR design Operating Basis Earthquake (OBE) of 0.08 g horizontal or0.053 g vertical acceleration. Seismic events of this magnitude can cause damage to plant safetyfunctions.The method of determining whether the OBE has been exceeded relies on either the actuation ofor evaluation of data from the CCNPP seismic monitor or indication of actual degraded systemperformance with seismic activity confirmed by shift operators on duty in the Control Roomdetermining that the ground motion was felt or corroborated by the NEIC. According to 01-46,confirmation by one or more Control Room operators with respect to ground motion helps avoidunnecessary classification if the seismic switches inadvertently trip or detect vibrations not relatedto an earthquake.CCNPP seismic instrumentation actuates at 0.01g upon sensing any seismic activity.The National Earthquake Information Center (NEIC) can confirm seismic activity in the vicinity ofthe CCNPP. The NEIC can be contacted by calling (303) 273-8500. Select option #1 and informthe analyst you wish to confirm recent seismic activity in the vicinity of Calvert Cliffs Nuclear PowerPlant. Provide the analyst with the following CCNPP coordinates: 330 25' 39.7" north latitude, 76026' 45" west longitude (ref. 3). Alternatively, information regarding the extent of a near-siteearthquake can be obtained by calling the University of Delaware (302) 821-1576.Definitions:Safety-Related Structures, Systems and Components (as defined in 10CFR50.2)Those structures, systems and components that are relied upon to remain functional duringand following design basis events to assure:(1) The integrity of the reactor coolant pressure boundary;(2) The capability to shut down the reactor and maintain it in a safe shutdown condition;(3) The capability to prevent or mitigate the consequences of accidents which could resultin potential offsite exposures.February 2016 133 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCCNPP Basis Reference(s):1. 0I-46 Seismic Measurement Equipment2. UFSAR Section 7.5.7 Seismic Instrumentation3. Calvert Cliffs ISFSI USAR Section 2.1.1 Site Location4. STPI M-260-0 Seismic Instrumentation Channel Check5. NEI 99-01 HA16. ECP-1 3-000653, Replace the existing five channel SMA-3 Seismic Montitor with a KinemetricsCondor Seismic Monitoring SystemFebruary 2016134EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryAnnexFxAlnn NunlnarW Vl I vml ........ m I I ....Category:Subcategory:H -Hazards and Other Conditions Affecting Plant SafetyI -Natural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting Vital AreasEAL:HA1.2 AlertTornado striking or sustained high winds > 45 rn/sec (100 mph) resulting in EITHER:VISIBLE DAMAGE to ANY SAFETY-RELATED STRUCTURE, SYSTEM, ORCOMPONENT within ANY Table H-I areaORControl Room indication of degraded performance of ANY SAFETY-RELATEDSTRUCTURE, SYSTEM, OR COMPONENT within ANY Table H-I areaTable H-I Safe Shutdown Areas* Control Room* Containment* Auxiliary Building* Diesel Generator Rooms* Intake Structure* IA/0C DG Buildings* RWT* RWT Rooms* CST No. 12* FOSTNo. 21* Auxiliary Feed Pump RoomsMode Applicability:AllBasis:GenericThis EAL escalates from HU1.2 in that the occurrence of the event has resulted in visible damageto plant structures or areas containing equipment necessary for a safe shutdown, or has causeddamage to the safety systems in those structures evidenced by Control Room indications ofdegraded system response or performance. The occurrence of visible damage and/or degradedsystem response is intended to discriminate against lesser events. The initial report should not beinterpreted as mandating a lengthy damage assessment prior to classification. No attempt is madeFebruary 2016135EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearin this EAL to assess the actual magnitude of the damage. The significance here is not that aparticular system or structure was damaged, but rather, that the event was of sufficient magnitudeto cause this degradation.Escalation of this emergency classification level, if appropriate, would be based on SystemMalfunction EALs.This EAL is based on a tornado striking (touching down) or high winds that have caused visibledamage to structures containing functions or systems required for safe shutdown of the plant.Plant-SpecificThis threshold addresses events that may have resulted in a Safe Shutdown Area being subjectedto forces beyond design limits and thus damage may be assumed to have occurred to plant safetysystems. Safe Shutdown Areas are vital areas that house equipment the operation of which maybe needed to ensure the reactor safely reaches and is maintained in cold shutdown. SafeShutdown Areas include structures that contain the equipment of concern. The Alert classificationis appropriate if relevant plant parameters indicate that the performance of safety systems in theaffected Safe Shutdown Areas has been degraded. No attempt should be made to fully inventorythe actual magnitude of the damage or quantify the degradation of safety system performance priorto declaration of an Alert under this threshold.This EAL is based on the structural design basis of 100 mph. Wind loads of this magnitude cancause damage to safety functions. The meteorological tower 15-minute average wind speedreadings are the "sustained" wind speeds used to assess this EAL.Table H-I Safe Shutdown Areas include all SAFETY-RELATED STRUCTURE, SYSTEM, ORCOMPONENT needed for safe shutdown.Definitions:Safety-Related Structures, Systems and Components (as defined in 10CFR50.2)Those structures, systems and components that are relied upon to remain functional duringand following design basis events to assure:(1) The integrity of the reactor coolant pressure boundary;(2) The capability to shut down the reactor and maintain it in a safe shutdown condition;(3) The capability to prevent or mitigate the consequences of accidents which could resultin potential offsite exposures.February 2016 136 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearVisible DamageDamage to equipment or structure that is readily observable without measurements, testing, oranalysis. Damage is sufficient to cause concern regarding the continued operability or reliabilityof affected safety structure, system, or component. Example damage includes: deformationdue to heat or impact, denting, penetration, rupture, cracking, paint blistering. Surfaceblemishes (e.g., paint chipping, scratches) should not be included.CCNPP Basis Reference(s):1. ES-005 Civil and Structural Design Criteria2. CCIPEEE RAN 97-031 High Winds, Floods and Other External Events Analysis Section 5.3.13. Drawing 61502 Plant Property and Buildings4. UFSAR Section 5A.2 Classes of Structures, Systems, and Equipment5. NEI 99-01 HAlFebruary 2016137EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 1 -Natural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting Vital AreasEAL:HA1.3 AlertInternal flooding in ANY Table H-i area resulting in EITHER:An electrical shock hazard that precludes access to operate or monitor ANY SAFETY-RELATED STRUCTURE, SYSTEM, OR COMPONENT within ANY Table H-i areaORControl Room indication of degraded performance of ANY SAFETY-RELATEDSTRucTuRE, SYSTEM, OR COMPONENT within ANY Table H-i areaTable H-I Safe Shutdown Areas,, Control Room* Containment* Auxiliary Building*, Diesel Generator Rooms* Intake Structure* 1A/0C DG Buildings* RWT* RWT Rooms* CST No. 12* FOST No. 21* Auxiliary Feed Pump RoomsMode Applicability:AllBasis:GenericEscalation of this emergency classification level, if appropriate, would be based on SystemMalfunction EALs.This EAL addresses the effect of internal flooding caused by events such as component failures,equipment misalignment, or outage activity mishaps. It is based on the degraded performance ofsystems, or has created industrial safety hazards (e.g., electrical shock) that preclude necessaryFebruary 2016 138 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearaccess to operate or monitor safety equipment. The inability to access, operate or monitor safetyequipment represents an actual or substantial potential degradation of the level of safety of theplant.Flooding as used in this EAL describes a condition where water is entering the room faster thaninstalled equipment is capable of removal, resulting in a rise of water level within the room.Classification of this EAL should not be delayed while corrective actions are being taken to isolatethe water source.PlIant-SprecificThis threshold addresses the effect of flooding caused by internal events such as componentfailures such as Circulating, Saltwater, Component Cooling or Service Water line ruptures,equipment misalignment, fire suppression system actuation, steam leaks or outage activitymishaps. The Internal Flooding Areas contain systems that are:* Required for safe shutdown of the plant* Not designed to be wetted or submerged* Susceptible to internal flooding eventsUncontrolled internal flooding that has degraded safety-related equipment or created a safetyhazard precluding access necessary for the safe operation or monitoring of safety equipmentwarrants declaration of an Alert.Definitions:Safety-Related Structures, Systems and Components (as defined in 100FR50.2)Those structures, systems and components that are relied upon to remain functional duringand following design basis events to assure:(1) The integrity of the reactor coolant pressure boundary;(2) The capability to shut down the reactor and maintain it in a safe shutdown condition;(3) The capability to prevent or mitigate the consequences of accidents which could resultin potential offsite exposures.February 2016 139 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCCNPP Basis Reference(s):1. CCPRA RAN: 96-024FLOOD Flood Rule Development2. CCPRA RAN: 98-062, Internal Flood Initiating Event Frequencies3. CCPRA RAN: 98-065, Flood Evaluations (Flood Queries)4. 1C10-ALM ESFAS 13 Alarm Manual, J-17, CC PP RM LVL HI5. 1C10-ALM ESFAS 13 Alarm Manual, J-18, SRW PP RM LVL HI6. 1CI0-ALM ESFAS 13 Alarm Manual, J-22, CNDSR PIT LVL HI7. 1C10-ALM ESFAS 13 Alarm Manual, J-23, INTAKE SUMP STRUCTURE LVL HI8. 1C1O-ALM ESFAS 13 Alarm Manual, J-24, INTAKE STRUCTURE OH TRIP9. NEI 99-01 HA1February 2016140EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:S ubcateg ory:H -Hazards and Other Conditions Affecting Plant SafetyI -Natural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting Vital AreasEAL:HA1.4 AlertTurbine failure-generated PROJECTILES resulting in EITHER:VISIBLE DAMAGE to or penetration of ANY SAFETY-RELATED STRUCTURE,SYSTEM, OR COMPONENT within ANY Table H-I areaORControl Room indication of degraded performance of ANY SAFETY-RELATEDSTRUCTURE, SYSTEM, OR COMPONENT within ANY Table H-i areaTable H-I Safe Shutdown Areas* Control Room* Containment* Auxiliary Building* Diesel Generator Rooms* Intake Structure* lA/0C DO Buildings* RWT* RWT Rooms* CST No. 12* FOSTNo. 21* Auxiliary Feed Pump RoomsMode Applicability:AllBasis:GenericThis EAL escalates from HU1 .4 in that the occurrence of the event has resulted in visible damageto plant structures or areas Containing equipment necessary for a safe shutdown, or has causeddamage to the safety systems in those structures evidenced by Control Room indications ofdegraded system response or performance. The occurrence of visible damage and/or degradedsystem response is intended to discriminate against lesser events. The initial report should not beFebruary 2016141EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearinterpreted as mandating a lengthy damage assessment prior to classification. No attempt is madein this EAL to assess the actual magnitude of the damage. The significance here is not that aparticular system or structure was damaged, but rather, that the event was of sufficient magnitudeto cause this degradation.Escalation of this emergency classification level, if appropriate, would be based on SystemMalfunction EALs.This EAL addresses the threat to safety related equipment imposed by projectiles generated bymain turbine rotating component failures. Therefore, this EAL is consistent with the definition of anAlert in that the potential exists for actual or substantial potential degradation of the level of safetyof the plant.Plant-SpecificThe turbine generator stores large amounts of rotational kinetic energy in its rotor. In the unlikelyevent of a major mechanical failure, this energy may be transformed into both rotational andtranslational energy of rotor fragments. These fragments may impact the surrounding stationaryparts. If the energy-absorbing capability of these stationary turbine generator parts is insufficient,external projectiles will be released. These ejected projectiles may impact various plant structures,including those housing safety related equipment.Table H-i Safe Shutdown Areas include all SAFETY-RELATED STRUCTURE, SYSTEM, ORCOMPONENT needed for safe shutdown.Definitions:ProjectileAn object directed toward a NPP that could cause concern for its continued operability,reliability, or personnel safety.Safety-Related Structures, Systems and Components (as defined in 10CFR50.2)Those structures, systems and components that are relied upon to remain functional duringand following design basis events to assure:(1) The integrity of the reactor coolant pressure boundary;(2) The capability to shut down the reactor and maintain it in a safe shutdown condition;(3) The capability to prevent or mitigate the consequences of accidents which could resultin potential offsite exposures.February 2016 142 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearVisible DamageDamage to equipment or structure that is readily observable without measurements, testing, oranalysis. Damage is sufficient to cause concern regarding the continued operability or reliabilityof affected safety structure, system, or component. Example damage includes: deformationdue to heat or impact, denting, penetration, rupture, cracking, paint blistering. Surfaceblemishes (e.g., paint chipping, scratches) should not be included.CCNPP Basis Reference(s):1. Drawing 61502 Plant Property and Buildings2. UFSAR Section 5A.2 Classes of Structures, Systems, and Equipment3. CCIPEEE RAN 97-031 High Winds, Floods and Other External Events Analysis Section 5.3.14. NEI 99-01 HA1February 2016143EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 1 -Natural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting Vital AreasEAL:HA1.5 AlertBay water level > top of the traveling screen cover housingORBay water level or inside travelling screen water level < 16.0 ft below intake concrete level(-72.0 in. Mean Sea Level)Mode Applicability:AllBasis:GenericThis EAL addresses other site specific phenomena that result in visible damage to vital areas orresults in indication of damage to safety structures, systems, or components containing functionsand systems required for safe shutdown of the plant that can also be precursors of more seriousevents.Plant-SpecificThis threshold covers high and low water level conditions that may have resulted in a plant VitalArea being subjected to levels beyond design limits, and thus damage may be assumed to haveoccurred to plant safety systems.Since the Intake Structure houses the saltwater pumps that are essential for safe shutdown ofCCNPP, the structure was designed as a Category I structure for seismic, tornado, and hurricaneconditions. The Intake Structure is also designed to protect the saltwater pump motors fromexternal flooding due to the maximum hypothetical hurricane tide and storm surges, including waveaction. The Intake Structure design loads and conditions are shown in UFSAR Table 5-7.18 ft Mean Sea Level (+216 in., top of the travelling screen cover) is the design flood level.The predicted extreme low tide elevation is -3.6 ft Mean Sea Level. However, the plant has beendesigned for -4.0 ft Mean Sea Level and can continue to operate with an extreme low waterElevation of-6.0 ft (-72.0 in.) Mean Sea Level. This EAL criterion is met if the water is 16 ft belowthe intake concrete level by observation. This measurement requires judgment because the BayFebruary 2016 144 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclearsurface is not normally still. Bay water level is upstream (i.e., before) the travelling screens. Insidetravelling screen water level is considered at the Alert classification because differential pressureacross the screens may depress the level below the bay water level and reduce NPSH available tothe saltwater pumps. The top of the saltwater pump intake is at -9.5 ft Mean Sea Level.Radar probes (1-LIT-I1100 & 2-LIT-2100) have been installed which provide local indication (1-LI-1100 & 2-LI-21 00) of Intake water level in inches relative to Mean Sea Level (ref. 4).CCNPP Basis Reference(s):1. UFSAR Sections 2.8.3.6 and 2.8.3.72. UFSAR Table 5-73. 1C10-ALM ESFAS 14 Alarm Manual, J-234. ECP-10-0002085. NEI 99-01 HA1February 2016145EP-AA-1011 Addendum 3(Revision 1)

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• ilMVlVV41Category:Subcategory:H -Hazards and Other Conditions Affecting Plant SafetyI -Natural or Destructive PhenomenaInitiating Condition: Natural or destructive phenomena affecting Vital AreasEAL:HA1.6 ,AlertVehicle crash resulting in EITHER:VISIBLE DAMAGE to ANY SAFETY-RELATED STRUCTURE, SYSTEM, ORCOMPONENT within ANY Table H-I areaORControl Room indication of degraded performance of ANY SAFETY-RELATEDSTRUCTURE, SYSTEM, OR COMPONENT within ANY Table H-I areaLTable H-I Safe Shutdown Areas* Control Room* Containment* Auxiliary Building* Diesel Generator Rooms* Intake Structure* 1A/0C DG Buildings* RWT* RWT Rooms* CST No. 12* FOSTNo. 21* Auxiliary Feed Pump RoomsMode Applicability:AllBasis:GenericThe occurrence of visible damage and/or degraded system response is intended to discriminateagainst lesser events. The initial report should not be interpreted as mandating a lengthy damageassessment prior to classification. No attempt is made in this EAL to assess the actual magnitudeof the damage. The significance here is not that a particular system or structure was damaged, butrather, that the event was of sufficient magnitude to cause this degradation.February 2016146EP-AA-1011 Addendum 3(Revision I)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearEscalation of this emergency classification level, if appropriate, would be based on SystemMalfunction EALs.This EAL addresses vehicle crashes within the Protected Area that results in visible damage tovital areas or indication of damage to safety structures, systems, or components containingfunctions and systems required for safe shutdown of the plant.Plant-SpecificThis EAL is intended to address crashes of vehicle types large enough to cause significantdamage to plant structures containing functions and systems required for safe shutdown of theplant. Vehicle types include automobiles, aircraft, trucks, cranes, forklifts, waterborne craft, etc.Table H-I Safe Shutdown Areas include all SAFETY-RELATED STRUCTURE, SYSTEM, ORCOMPONENT needed for safe shutdown.Definitions:Safety-Related Structures, Systems and Components (as defined in 10CFR50.2)Those structures, systems and components that are relied upon to remain functional duringand following design basis events to assure:(I) The integrity of the reactor coolant pressure boundary;(2) The capability to shut down the reactor and maintain it in a safe shutdown condition;(3) The capability to prevent or mitigate the consequences of accidents which could resultin potential offsite exposures.Visible DamageDamage to equipment or structure that is readily observable without measurements, testing, oranalysis. Damage is sufficient to cause concern regarding the continued operability or reliabilityof affected safety structure, system, or component. Example damage includes: deformationdue to heat or impact, denting, penetration, rupture, cracking, paint blistering. Surfaceblemishes (e.g., paint chipping, scratches) should not be included.CCNPP Basis Reference(s):I. Drawing 61502 Plant Property and Buildings2. UFSAR Section 5A.2 Classes of Structures, Systems, and Equipment3. NEI 99-01 HA1February 2016 147 EP-AA-1011 Addendum 3(Revision I)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexIFxelnn Nuc~learCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 2 -Fire or ExplosionInitiating Condition: Fire within the Protected Area not extinguished within 15 min. ofdetection or explosion within the Protected AreaEAL:HU2.1 Unusual EventFIRE not extinguished within 15 min. of Control Room notification or verification of aControl Room fire alarm in the North Service Building, Turbine Building, Butler Building(Note 9) or ANY Table H-I area (Note 4)* Butler Building is only considered adjacent in Modes 5, 6 or D.Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time.Note 9: Butler Building is only considered adjacent in Modes 5, 6 and D.Table H-I Safe Shutdown Areas* Control Room* Containment* Auxiliary Building* Diesel Generator Rooms* Intake Structure* 1A/0C DG Buildings* RWT* RWT Rooms* CST No. 12* FOST No. 21* Auxiliary Feed Pump Rooms* Service Water Rooms* Switchgear RoomsMode Applicability:AllFebruary 2016148EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBasis:GenericThis EAL addresses the magnitude and extent of fires that may be potentially significant precursorsof damage to safety systems. It addresses the FIRE, and not the degradation in performance ofaffected systems that may result.As used here, detection is visual observation and report by plant personnel or sensor alarmindication.The purpose of this threshold is to address the magnitude and extent of fires that may bepotentially significant precursors to damage to safety systems. As used here, notification is visualobservation and report by plant personnel or sensor alarm indication. The 15-minute period toextinguish the fire begins with a credible notification that a fire is occurring or indication of a validfire detection system alarm. Determination of a valid fire detection system alarm includes actionsthat can be taken within the Control Room or at nearby Fire Panels to determine that the alarm isnot spurious. These actions include the use of direct or indirect indications such as redundantalarms or instrumentation readings associated with the area to ensure the alarm is not spuriousand is an indication of a fire. An alarm verified in this manner is assumed to be an indication of afire unless personnel dispatched to the scene disprove the alarm within the 15-minute period. Thereport, however, shall not be required to verify the alarm.The intent of this 15 minute duration is to size the fire and to discriminate against small fires thatare readily extinguished (e.g., smoldering waste paper basket).Plant-SpjecificTable H-I Safe Shutdown Areas include all SAFETY-RELATED STRUCTURE, SYSTEM, ORCOMPONENT needed for safe shutdown. The North Service Building, Turbine Building andButler Building (only when in Modes 5, 6 or D) are adjacent structures.Definitions:FireCombustion characterized by heat and light. Sources of smoke such as slipping drive belts oroverheated electrical equipment do not constitute fires. Observation of flame is preferred but isnot required if large quantities of smoke and heat are observed.CCNPP Basis Reference(s):1. Drawing 61502 Plant Property and Buildings2. UFSAR Section 5A.2 Classes of Structures, Systems, and Equipment3. AOP-9 Series Fire Procedures4. NEI 99-01 HU2February 2016 149 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 2 -Fire or ExplosionInitiating Condition: Fire within the Protected Area not extinguished within 15 mai. ofdetection or explosion within the Protected AreaEAL:HU2.2 Unusual EventEXPLOSION within the PROTECTED AREAMode Applicability:AllBasis:GenericThis EAL addresses the magnitude and extent of explosions that may be potentially significantprecursors of damage to safety systems. It addresses the explosion, and not the degradation inperformance of affected systems that may result.This EAL addresses only those explosions of sufficient force to damage permanent structures orequipment within the Protected Area.No attempt is made to assess the actual magnitude of the damage. The occurrence of theexplosion is sufficient for declaration.The Emergency director also needs to consider any security aspects of the explosion, if applicable.Escalation of this emergency classification level, if appropriate, would be based on EAL HA2.1.Plant-SpecificWhile some explosions may also result in fires that exceed EAL HU2.1, no fire is necessary todeclare an emergency in the event of an explosion. If a fire also occurs as a result or with anexplosion, declare the Unusual Event based on the explosion and monitor the progress of the firefor potential escalation due to fire damage.When used in the context of an explosion, "catastrophic failure" of a component (e.g., tank, heatexchanger, etc.) signifies a rupture of sufficient magnitude that adjacent or nearby components areaffected.February 2016 150 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearOperatin~q exp:erience6/25/09 Davis-Besse -A transitory Alert condition was determined to have existed based on'Onsite Explosion Affecting Plant Operation'. A catastrophic failure-explosion of the ConstantCurrent Potential Device (CCPD) on 'J' Bus near Air Circuit Breaker (ACB) 34563 resulted in a lossof switchyard 345 KV Bus 'J'. This event de-energized Startup Transformer 01 which is a tie fromoffsite sources to the Unit 13.8 KV Busses. The licensee stated that initially, the severity of theCCPD failure was not recognized because of the night time conditions and minimal lighting in thearea. After daylight examination of the location of the event, it was determined that the failure ofthe CCPD should have been classified as an explosion affecting plant operation. Consequently,the licensee made the after-the-fact declaration.10/27/08 Quad Cities -Quad Cities Station declared an Unusual Event due to an explosion in theprotected area. The radwaste floor drain surge tank building had physical damage after reports ofan explosion in the area. The damage was to the block structure of the radwaste floor drain surgetank building but the radwaste tank itself was not impacted. The cause of the explosion was stillunknown but appeared to be related to a buildup of some kind of hydrocarbon gas.Definitions:Explosion.A rapid, violent, unconfined combustion, or catastrophic failure of pressurized/energizedequipment that imparts energy of sufficient force to potentially damage permanent structures,systems, or components.Protected AreaThe site specific area which normally encompasses all controlled areas within the securityProtected Area fence.CCNPP Basis Reference(s):1. Drawing 61502 Plant Property and Buildings2. NEI 99-01 HU2February 2016 151 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:H -Hazards and Other Conditions Affecting Plant Safety2 -Fire or ExplosionInitiating Condition: Fire or explosion affecting the operability of plant safety systemsrequired to establish or maintain safe shutdownEAL:HA2.1 AlertFIRE or EXPLOSION resulting in EITHER:VISIBLE DAMAGE to ANY SAFETY-RELATED STRUCTURE, SYSTEM, ORCOMPONENT within ANY Table H-I areaORControl Room indication of degraded performance of ANY SAFETY-RELATEDSTRUCTURE, SYSTEM, OR COMPONENT within ANY Table H-I areaTable H-I Safe Shutdown Areas* Control Room* Containment* Auxiliary Building* Diesel Generator Rooms* Intake Structure* 1A/0C DG Buildings* RWT* RWT Rooms* CST No. 12* FOSTNo. 21* Auxiliary Feed Pump RoomsMode Applicability:AllBasis:GenericVisible damage is used to identify the magnitude of the fire or explosion and to discriminate againstminor fires and explosions.The reference to structures containing safety systems or components is included to discriminateagainst fires or explosions in areas having a low probability of affecting safe operation. TheFebruary 2016152EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearsignificance here is not that a safety system was degraded but the fact that the fire or explosionwas large enough to cause damage to these systems.The use of visible damage should not be interpreted as mandating a lengthy damage assessmentprior to classification. The declaration of an Alert and the activation of the Technical SupportCenter will provide the Emergency Director with the resources needed to perform detailed damageassessments.The Emergency Director also needs to consider any security aspects of the explosion.Escalation of this emergency classification level, if appropriate, will be based on EALs in Category5, Category F or Category R.Plant-SpecificTable H-I Safe Shutdown Areas include all SAFETY-RELATED STRUCTURE, SYSTEM, ORCOMPONENT needed for safe shutdown.Definitions:ExplosionA rapid, violent, unconfined combustion, or catastrophic failure of pressurized/energizedequipment that imparts energy of sufficient force to potentially damage permanent structures,systems, or components.FireCombustion characterized by heat and light. Sources of smoke such as slipping drive belts oroverheated electrical equipment do not constitute fires. Observation of flame is preferred but isnot required if large quantities of smoke and heat are observed.Safety-Related Structures, Systems and Components (as defined in 10CFR50.2)Those structures, systems and components that are relied upon to remain functional duringand following design basis events to assure:(1) The integrity of the reactor coolant pressure boundary;(2) The capability to shut down the reactor and maintain it in a safe shutdown condition;(3) The capability to prevent or mitigate the consequences of accidents which could resultin potential offsite exposures.Visible DamageDamage to equipment or structure that is readily observable without measurements, testing, oranalysis. Damage is sufficient to cause concern regarding the continued operability or reliabilityof affected safety structure, system, or component. Example damage includes: deformationdue to heat or impact, denting, penetration, rupture, cracking, paint blistering. Surfaceblemishes (e.g., paint chipping, scratches) should not be included.February 2016 153 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexFvcInn ...................... m m CCNPP Basis Reference(s):1. Drawing 61502 Plant Property and Buildings2. UFSAR Section 5A.2 Classes of Structures, Systems, and Equipment3. NEI 99-01 HA2February 2016154EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexEYAlnn NuclearCategory:H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 3 -Hazardous GasInitiating Condition: Release of toxic, corrosive, asphyxiant or flammable gasesdeemed detrimental to normal plant operationsEAL:SHU3.1Unusual EventIToxic, corrosive, asphyxiant or flammable gases in amounts that have or could adverselyaffect NORMAL PLANT OPERATIONSMode Applicability:-AllBasis:GenericThis EAL is based on the release of toxic, corrosive, asphyxiant or flammable gases of sufficientquantity to affect normal plant operations.The fact that SCBA may be worn does not eliminate the need to declare the event.This EAL is not intended to require significant assessment or quantification. It assumes anuncontrolled process that has the potential to affect plant operations. This would preclude small orincidental releases, or releases that do not impact structures needed for plant operation.An asphyxiant is a gas capable of reducing the level of oxygen in the body to dangerous levels.Most commonly, asphyxiants work by merely displacing air in an enclosed environment. Thisreduces the concentration of oxygen below the normal level of around 19%, which can lead tobreathing difficulties, unconsciousness or even death.Escalation of this emergency classification level, if appropriate, would be based on EAL HA3.1.Plant-SpecificAsphyxiant gases include carbon dioxide, smoke, etc.Definitions:Normal Plant OperationsActivities at the plant site associated with routine testing, maintenance, or equipmentoperations, in accordance with normal operating or administrative procedures. Entry intoabnormal or emergency operating procedures, or deviation from normal security or radiologicalcontrols posture, is a departure from Normal Plant Operations.February 2016155EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryExelon NuclearCalvert Cliffs AnnexCCNPP Basis Reference(s):1. NEI 99-01 HU3February 2016156EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/Proprietary('zlvprt CliffR AnncxFYAIlnn N~ir~nlnrCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 3 -Hazardous GasInitiating Condition: Release of toxic, corrosive, asphyxiant or flammable gasesdeemed detrimental to normal plant operationsEAL:SHU3.2 Unusual EventRecommendation by local, county or state officials to evacuate or shelter site personnelbased on offsite eventMode Applicability:AllBasis:GenericEscalation of this emergency classification level, if appropriate, would be based on EAL HA3. 1.Plant-SpecificNoneCCNPP Basis Reference(s):1. NEI 99-01 HU3February 2016157EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexIFxelon Nurlea~rCategory:Subcategory:H -Hazards and Other Conditions Affecting Plant Safety3 -Hazardous GasInitiating Condition: Access to a Vital Area is prohibited due to toxic, corrosive,asphyxiant or flammable gases which jeopardize operation ofoperable equipment required to maintain safe operations or safelyshutdown the reactorEAL:HA3.1 AlertAccess to ANY of the following areas is prohibited due to toxic, corrosive, asphyxiant orflammable gases (Note 5):* Control Room* 45' West Electrical Penetration Rooms* 69' Electrical Penetration Rooms* ECCS Pump Rooms* Charging Pump Rooms* Component Cooling RoomsNote 5: If the equipment in the stated area was already inoperable, or out of service, before the event occurred, thenEAL HA3.1 should not be declared as it will have no adverse impact on the ability of the plant to safelyoperate or safely shutdown beyond that already allowed by Technical Specifications at the time of the event.Mode Applicability:AllBasis:GenericGases in a Vital Area can affect the ability to safely operate or safely shutdown the reactor.The fact that SCBA may be worn does not eliminate the need to declare the event.Declaration should not be delayed for confirmation from atmospheric testing if the atmosphereposes an immediate threat to life and health or an immediate threat of severe exposure to gases.This could be based upon documented analysis, indication of personal ill effects from exposure, oroperating experience with the hazards.If the equipment in the stated area was already inoperable, or out of service, before the eventoccurred, then this EAL should not be declared as it will have no adverse impact on the ability ofthe plant to safely operate or safely shutdown beyond that already allowed by TechnicalSpecifications at the time of the event.February 2016158EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexlEYAInn Nuinl~sr................ i I An asphyxiant is a gas capable of reducing the level of oxygen in the body to dangerous levels.Most commonly, asphyxiants work by merely displacing air in an enclosed environment. Thisreduces the concentration of oxygen below the normal level of around 19%, which can lead tobreathing difficulties, unconsciousness or even death.An uncontrolled release of flammable gasses within a facility structure has the potential to affectsafe operation of the plant by limiting either operator or equipment operations due to the potentialfor ignition and resulting equipment damage/personnel injury. Flammable gasses, such ashydrogen and acetylene, are routinely used to maintain plant systems (hydrogen) or to repairequipment/components (acetylene -used in welding). This EAL assumes concentrations offlammable gasses which can ignite/support combustion.Escalation of this emergency classification level, if appropriate, will be based on EALs in CategoryS, Category F or Category R.Plant-SpecificLocations designated in the EAL are those areas that are required for Cold Shutdown that cannotbe completed from the Control Room.CCNPP Basis Reference(s):1. NEI 99-01 HA3February 2016159EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryC~lvnrt An n~xN=iilcI:2ry Vi v III IV I II II iVel iWMVIV1/41Category:Su bcateg ory:H -Hazards and Other Conditions Affecting Plant Safety4 -SecurityInitiating Condition: Confirmed security condition or threat which indicates a potentialdegradation in the level of safety of the plantEAL:HU4.1 Unusual EventA SECURITY CONDITION that does not involve a HOSTILE ACTION as reported bySecurity Shift SupervisorORA credible site-specific security threat notificationORA validated notification from NRC providing information of an aircraft threatMode Applicability:AllBasis:GenericNote: Timely and accurate communication between Security Shift Supervision and the ControlRoom is crucial for the implementation of effective Security EALs.Security events which do not represent a potential degradation in the level of safety of the plant arereported under 10 CFR 73.71 or in some cases under 10 CFR 50.72. Security events assessed ashostile actions are classifiable under EAL HA4.1, EAL HS4.1 and EAL HG4.1.A higher initial classification could be made based upon the nature and timing of the security threatand potential consequences. The licensee shall consider upgrading the emergency responsestatus and emergency classification level in accordance with the CCNPP Security and SafeguardsContingency Plan.First ConditionReference is made to the security shift supervisor because these individuals are the designatedpersonnel on-site qualified and trained to confirm that a security event is occurring or has occurred.Training on security event classification confirmation is closely controlled due to the strict secrecycontrols placed on the plant Security and Safeguards Contingency Plan.This threshold is based on the CCNPP Security and Safeguards Contingency Plan. The CCNPPSecurity and Safeguards Contingency Plan is based on guidance provided by NEI 03-12.February 2016160EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearSecond ConditionThis threshold is included to ensure that appropriate notifications for the security threat are made ina timely manner. This includes information of a credible threat. Only the plant to which the specificthreat is made need declare the Unusual Event.The determination of "credible" is made through use of information found in the CCNPP Securityand Safeguards Contingency Plan.Third ConditionThe intent of this EAL is to ensure that notifications for the aircraft threat are made in a timelymanner and that Offsite Response Organizations and plant personnel are at a state of heightenedawareness regarding the credible threat. It is not the intent of this EAL to replace existing non-hostile related EALs involving aircraft.This EAL is met when a plant receives information regarding an aircraft threat from NRC.Validation is performed by calling the NRC or by other approved methods of authentication. Onlythe plant to which the specific threat is made need declare the Unusual Event.The NRC Headquarters Operations Officer (HOO) will communicate to the licensee if the threatinvolves an airliner (airliner is meant to be a large aircraft with the potential for causing significantdamage to the plant). The status and size of the plane may be provided by NORAD through theNRC.Escalation to Alert emergency classification level via EAL HA4. 1 would be appropriate if the threatinvolves an airliner within 30 minutes of the plant.Plant-SpecificIf the Security Shift Supervisor determines that a threat notification is credible, the Security ShiftSupervisor will notify the Operations Shift Manager that a "Credible Threat" condition exists forCalvert Cliffs. Generally, Calvert Cliffs Security Procedures address standard practices fordetermining credibility. The three main criteria for determining credibility are: technical feasibility,operational feasibility, and resolve. For Calvert Cliffs, a validated notification delivered by the FBI,NRC or similar agency is treated as credible.Definitions:AirlinerlLarge AircraftAny size or type of aircraft with the potential for causing significant damage to the plant (refer tothe Security Plan for a more detailed definition).February 2016 161 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearHostile ActionAn act toward CON PP or its personnel that includes the use of violent force to destroyequipment, take hostages, and/or intimidate the licensee to achieve an end. This includesattack by air, land, or water using guns, explosives, projectiles, vehicles, or other devices usedto deliver destructive force. Other acts that satisfy the overall intent may be included.Hostile Action should not be construed to include acts of civil disobedience or felonious actsthat are not part of a concerted attack on CCNPP. Non-terrorism-based EALs should be usedto address such activities, (e.g., violent acts between individuals in the owner controlled area).Security ConditionAny security event as listed in the approved security contingency plan that constitutes athreat/compromise to site security, threat/risk to site personnel, or a potential degradation to thelevel of safety of the plant. A~security condition does not involve a hostile action.CCNPP Basis Reference(s):1. CCNPP Security and Safeguards Contingency Plan2. NEI 99-01 HU4February 2016162EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryrlvIrt AnnmeFvI::nn rCategory:S ubcateg ory:H -Hazards and Other Conditions Affecting Plant Safety4 -SecurityInitiating Condition: Hostile action within the Owner Controlled Area or airborne attackthreatEAL:HA4.1 AlertA HOSTILE ACTION is occurring or has occurred within the Owner Controlled Area asreported by Security Shift SupervisorORA validated notification from NRC of an AIRLINER attack threat within 30 min. of the siteMode Applicability:AllBasis:GenericNote: Timely and accurate communication between Security Shift Supervision and the ControlRoom is crucial for the implementation of effective Security EALs.This EAL addresses the contingency for a very rapid progression of events, such as thatexperienced on September 11, 2001. They are not premised solely on the potential for aradiological release. Rather the issue includes the need for rapid assistance due to the possibilityfor significant and indeterminate damage from additional air, land or water attack elements.The fact that the site is under serious attack or is an identified attack target with minimal timeavailable for further preparation or additional assistance to arrive requires a heightened state ofreadiness and implementation of protective measures that can be effective (such as on-siteevacuation, dispersal or sheltering).First ConditionThis condition addresses the potential for a very rapid progression of events due to a hostileaction. It is not intended to address incidents that are accidental events or acts of civildisobedience, such as small aircraft impact, hunters, or physical disputes between employeeswithin the Owner Controlled Area. Those events are adequately addressed by other EALs.Note that this condition is applicable for any hostile action occurring, or that has occurred, in theOwner Controlled Area including the Independent Spent Fuel Storage Installation (ISFSI).February 2016163EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearSecond ConditionThis condition addresses the immediacy of an expected threat arrival or impact on the site within arelatively short time.The intent of this condition is to ensure that notifications for the airliner attack threat are made in atimely manner and that Offsite Response Organizations (OROs) and plant personnel are at a stateof heightened awareness regarding the credible threat. Airliner is meant to be a large aircraft withthe potential for causing significant damage to the plant.This condition is met when a plant receives information regarding an airliner attack threat fromNRC and the airliner is within 30 minutes of the plant. Only the plant to which the specific threat ismade need declare the Alert.The NRC Headquarters Operations Officer (HOO) will communicate to the licensee if the threatinvolves an airliner (airliner is meant to be a large aircraft with the potential for causing significantdamage to the plant). The status and size of the plane may be provided by NORAD through theNRC.Plant-SpecificDefinitions:Airliner/Large AircraftAny size or type of aircraft with the potential for causing significant damage to the plant (refer tothe Security Plan for a more detailed definition).Hostile ActionAn act toward CCNPP or its personnel that includes the use of violent force to destroyequipment, take hostages, and/or intimidate the licensee to achieve an end. This includesattack by air, land, or water using guns, explosives, projectiles, vehicles, or other devices usedto deliver destructive force. Other acts that satisfy the overall intent may be included.Hostile Action should not be construed to include acts of civil disobedience or felonious actsthat are not part of a concerted attack on CCNPP. Non-terrorism-based EALs should be usedto address such activities, (e.g., violent acts between individuals in the owner controlled area).CCNPP Basis Reference(s):1. CCNPP Security and Safeguards Contingency Plan2. NEI 99-01 HA4February 2016 164 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexIExelon Nurlea~r...................... m ...............Category:Subcategory:H -Hazards and Other Conditions Affecting Plant Safety4 -SecurityInitiating Condition: Hostile action within the Protected AreaEAL:HS4.1 Site Area EmergencyA HOSTILE ACTION is occurring or has occurred within the PROTECTED AREA asreported by Security Shift SupervisorMode Applicability:AllBasis:GenericThis condition represents an escalated threat to plant safety above that contained in the Alert inthat a hostile force has progressed from the Owner Controlled Area to the Protected Area.This EAL addresses the contingency for a very rapid progression of events, such as thatexperienced on September II, 2001. It is not premised solely on the potential for a radiologicalrelease. Rather the issue includes the need for rapid assistance due to the possibility for significantand indeterminate damage from additional air, land or water attack elements.The fact that the site is under serious attack with minimal time available for further preparation oradditional assistance to arrive requires Offsite Response Organization (ORO) readiness andpreparation for the implementation of protective measures.This EAL addresses the potential for a very rapid progression of events due to a hostile action. It isnot intended to address incidents that are accidental events or acts of civil disobedience, such assmall aircraft impact, hunters, or physical disputes between employees within the Protected Area.Those events are adequately addressed by other EALs.Escalation of this emergency classification level, if appropriate, would be based on actual plantstatus after impact or progression of attack.Plant-SpecificA hostile action that occurs or has occurred within the ISESI area is not classified under this EAL.The ISESI is located in the OCA and hostile action occurring in the ISESI would be classified underHA4.1. If hostile action in the ISESI results in damage to a cask confinement boundary, the eventwould meet the Unusual Event classification threshold for EAL EUI .1 as well as HA4.1.February 2016165EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearDefinitions:Hostile ActionAn act toward CCNPP or its personnel that includes the use of violent force to destroyequipment, take hostages, and/or intimidate the licensee to achieve an end. This includesattack by air, land, or water using guns, explosives, projectiles, vehicles, or other devices usedto deliver destructive force. Other acts that satisfy the overall intent may be included.Hostile Action should not be construed to include acts of civil disobedience or felonious actsthat are not part of a concerted attack on CCNPP. Non-terrorism-based EALs should be usedto address such activities, (e.g., violent acts between individuals in the owner controlled area).Protected AreaThe site specific area which normally encompasses all controlled areas within the securityProtected Area fence.CCNPP Basis Reference(s):1. CCNPP Security and Safeguards Contingency Plan2. NEI 99-01 HS4February 2016166EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:H -Hazards and Other Conditions Affecting Plant Safety4 -SecurityInitiating Condition: Hostile action resulting in loss of physical control of the facilityEAL:HG4.1 General EmergencyA HOSTILE ACTION has occurred such that plant personnel are unable to operateequipment required to maintain ANY of the following safety function acceptance criteria:* Reactivity control (RC)* Vital Auxiliaries (VA)* RCS pressure and inventory control (PlC)* Core & RCS heat removal (HR)Mode Applicability:AllBasis:GenericThis EAL encompasses conditions under which a hostile action has resulted in a loss of physicalcontrol of Vital Areas (containing vital equipment or controls of vital equipment) required tomaintain safety functions and control of that equipment cannot be transferred to and operated fromanother location.If control of the plant equipment necessary to maintain safety functions can be transferred toanother location, then the threshold is not met.Plant-SpecificSafety functions of concern in this EAL include:* Reactivity control* RCS inventory control* ROS pressure control* Core & RCS heat removalThese safety functions are maintained by meeting the relevant EOP Safety Function AcceptanceCriteria (ref. 1).February 2016167EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearDefinitions:Hostile ActionAn act toward CCN PP or its personnel that includes the use of violent force to destroyequipment, take hostages, and/or intimidate the licensee to achieve an end. This includesattack by air, land, or water using guns, explosives, projectiles, vehicles, or other devices usedto deliver destructive force. Other acts that satisfy the overall intent may be included.Hostile Action should not be construed to include acts of civil disobedience or felonious actsthat are not part of a concerted attack on CCNPP. Non-terrorism-based EALs should be usedto address such activities, (e.g., violent acts between individuals in the owner controlled area).CCNPP Basis Reference(s):1. CCNPP Security and Safeguards Contingency Plan2. CEN-152 Combustion Engineering Emergency Procedure Guidelines3. NEI 99-01 HG1February 2016168EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 4 -SecurityInitiating Condition: Hostile action resulting in loss of physical control of the facilityEAL:HG4.2 General EmergencyA HOSTILE ACTION has caused failure of Spent Fuel Cooling systemsANDIMMINENT fuel damage is likelyMode Applicability:AllBasis:GenericThis EAL addresses failure of spent fuel cooling systems as a result of hostile action if imminentfuel damage is likely.Plant-SpecificDefinitions:Hostile ActionAn act toward CCNPP or its personnel that includes the use of violent force to destroyequipment, take hostages, and/or intimidate the licensee to achieve an end. This includesattack by air, land, or water using guns, explosives, projectiles, vehicles, or other devices usedto deliver destructive force. Other acts that satisfy the overall intent may be included.Hostile Action should not be construed to include acts of civil disobedience or felonious actsthat are not part of a concerted attack on CCNPP. Non-terrorism-based EALs should be usedto address such activities, (e.g., violent acts between individuals in the owner controlled area).ImminentMitigation actions have been ineffective, additional actions are not expected to be successful,and trended information indicates that the event or condition will occur. Where imminenttimeframes are specified, they shall apply.CCNPP Basis Reference(s):1. CCNPP Security and Safeguards Contingency Plan2. NEI 99-01 HGIFebruary 2016169EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory: H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 5 -Control Room EvacuationInitiating Condition: Control Room evacuation has been initiatedEAL:HA5.1 AlertControl Room evacuation has been initiatedMode Applicability:AllBasis:GenericWith the Control Room evacuated, additional support, monitoring and direction through theTechnical Support Center and/or other emergency response facilities may be necessary.Inability to establish plant control from outside the Control Room will escalate this event to a SiteArea Emergency.Plant-SpecificAOP-9A Control Room Evacuation and Safe Shutdown Due to a Severe Control Room Fire andAOP-1 1 Control Room Evacuation and Safe Shutdown -Non-Fire Conditions provide specificinstructions for evacuating the Control Room/Building and establishing plant control in alternatelocations.CCNPP Basis Reference(s):1. AOP-9A Control Room Evacuation and Safe Shutdown Due to a Severe Control Room Fire2. AOP-11I Control Room Evacuation and Safe Shutdown -Non-Fire Conditions3. NEI 99-01 HA5February 2016170EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryAnnmrFYAlnn NIclIa~rVR m Wl ..... Im mm I m Category:Subcategory:H -Hazards and Other Conditions Affecting Plant Safety5 -Control Room EvacuationInitiating Condition: Control Room evacuation has been initiated and plant controlcannot be establishedEAL:HS5.1 Site Area EmergencyControl Room evacuation has been initiated AND EITHER:Inability to establish Auxiliary Feedwater to at least one steam generator within 30 mai.(Note 4)ORInability to establish reactor coolant make-up (charging pump flow) within 60 min. (Note4)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soonas it is determined that the condition has exceeded, or will likely exceed, the applicable time.Mode Applicability:AllBasis:GenericThe intent of this EAL is to capture those events where control of the plant cannot be reestablishedin a timely manner. In this case, expeditious transfer of control of safety systems has not occurred(although fission product barrier damage may not yet be indicated).The intent of the EAL is to establish control of important plant equipment and knowledge ofimportant plant parameters in a timely manner. Primary emphasis should be placed on thosecomponents and instruments that supply protection for and information about safety functions.Typically, these safety functions are reactivity control (ability to shutdown the reactor and maintainit shutdown), reactor water level (ability to cool the core), and decay heat removal (ability tomaintain a heat sink).The determination of whether or not control is established at the remote shutdown panel is basedon Emergency Director (ED) judgment. The Emergency Director is expected to make a reasonable,informed judgment within the site specific time for transfer that the licensee has control of the plantfrom the remote shutdown panel.Escalation of this emergency classification level, if appropriate, would be by EALs in Category F orCategory R.February 2016171EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearPlant-SpecificAOP-9A Control Room Evacuation and Safe Shutdown Due to a Severe Control Room Fire andAOP-11I Control Room Evacuation and Safe Shutdown -Non-Fire Conditions provide specificinstructions for evacuating the Control Room/Building and establishing plant control in alternatelocations.An analysis was performed to determine how quickly control must be re-established at CCNPPwithout core uncovery or damage. A RETRAN simulation shows that the steam generators go dryat about 4"7 minutes for the AOP-9 (station fire) scenario. ROS pressure reaches the lowestpressurizer safety valve setpoint soon thereafter. Restoring feedwater within 45 minutes assuresthat RCS pressure remains below the safety valve setpoint thus avoiding inventory loss. Themaximum time allowable to restore RCS inventory for Appendix R (station fire) scenarios is 90minutes. Site Emergency declaration at 30 minutes and 60 minutes for inability to restorefeedwater and RCS make-up respectively thus constitutes a conservative action for emergencyresponse.This EAL is based on analysis and actual procedure walk throughs. Licensee Event Report (LER)50-371/89-009, Rev. 2, (transmitted to the NRC on July 7, 1989) documents the analysis thatdemonstrates the ability to safely shutdown Unit I in accordance with AOP-9.CCNPP Basis Reference(s)::1. AOP-9A Control Room Evacuation and Safe Shutdown Due to a Severe Control Room Fire2. AOP-11I Control Room Evacuation and Safe Shutdown -Non-Fire Conditions3. Letter, L.B. Russell (BG&E) to James H. Joyner (U.S. Nuclear Regulatory CommissionRegion I), Emergency Action Level Review Meeting, June 6, 19914. NEI 99-01 HS2February 2016 172 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:S ubcateg ory:H -Hazards and Other Conditions Affecting Plant Safety6 -JudgmentInitiating Condition: Other conditions existing that in the judgment of the EmergencyDirector warrant declaration of a UEEAL:HU6.1 Unusual EventOther conditions exist which in the judgment of the Emergency Director indicate thatevents are in progress or have occurred which:Indicate a potential degradation of the level of safety of the plantORIndicate a security threat to facility protection has been initiatedNo releases of radioactive material requiring offsite response or monitoring are expectedunless further degradation of safety systems occursMode Applicability:AllBasis:GenericThis EAL addresses unanticipated conditions not addressed explicitly elsewhere but that warrantdeclaration of an emergency because conditions exist which are believed by the EmergencyDirector to fall under the UE emergency classification level.Plant-SpecificNoneCCNPP Basis Reference(s):1. NEI 99-01 HU5February 2016173EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:H -Hazards and Other Conditions Affecting Plant Safety6 -JudgmentInitiating Condition: Other conditions exist that in the judgment of the EmergencyDirector warrant declaration of an AlertEAL:HA6.1 AlertOther conditions exist which in the judgment of the Emergency Director indicate thatevents are in progress or have occurred which involve:An actual or potential substantial degradation of the level of safety of the plantORA security event that involves probable life threatening risk to site personnel or damageto site equipment because of HOSTILE ACTIONANY releases are expected to be limited to small fractions of the EPA Protective ActionGuideline exposure levels (1,000 mRem TEDE and 5,000 mRem thyroid CDE)Mode Applicability:AllBasis:GenericThis EAL addresses unanticipated conditions not addressed explicitly elsewhere but that warrantdeclaration of an emergency because conditions exist which are believed by the EmergencyDirector to fall under the Alert emergency classification level.Plant-SpecificDefinitions:Hostile ActionAn act toward CCNPP or its personnel that includes the use of violent force to destroyequipment, take hostages, and/or intimidate the licensee to achieve an end. This includesattack by air, land, or water using guns, explosives, projectiles, vehicles, or other devices usedto deliver destructive force. Other acts that satisfy the overall intent may be included.Hostile Action should not be construed to include acts of civil disobedience or felonious actsthat are not part of a concerted attack on CCNPP. Non-terrorism-based EALs should be usedto address such activities, (e.g., violent acts between individuals in the owner controlled area).February 2016174EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexCCNPP Basis Reference(s):1. NEI 99-01 HA6Exelon NuclearFebruary 2016175EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:H -Hazards and Other Conditions Affecting Plant Safety6 -JudgmentInitiating Condition: Other conditions existing that in the judgment of the EmergencyDirector warrant declaration of a Site Area EmergencyEAL:HS6.1 Site Area EmergencyOther conditions exist which in the judgment of the Emergency Director indicate thatevents are in progress or have occurred which involve:Actual or likely major failures of plant functions needed for protection of the publicORHOSTILE ACTION that results in intentional damage or malicious acts; (1) toward sitepersonnel or equipment that could lead to the likely failure of or; (2) that preventeffective access to equipment needed for the protection of the publicANY releases are not expected to result in exposure levels which exceed EPA ProtectiveAction Guideline exposure levels (1,000 mRem TEDE and 5,000 mRem thyroid CDE)beyond the site boundaryMode Applicability:AllBasis:GenericThis EAL addresses unanticipated conditions not addressed explicitly elsewhere but that warrantdeclaration of an emergency because conditions exist which are believed by the EmergencyDirector to fall under the emergency classification level description for Site Area Emergency.Plant-Sp~ecificDefinitions:Hostile ActionAn act toward CCNPP or its personnel that includes the use of violent force to destroyequipment, take hostages, and/or intimidate the licensee to achieve an end. This includesattack by air, land, or water using guns, explosives, projectiles, vehicles, or other devices usedto deliver destructive force. Other acts-that satisfy the overall intent may be included.Hostile Action should not be construed to include acts of civil disobedience or felonious actsthat are not part of a concerted attack on CCNPP. Non-terrorism-based EALs should be usedto address such activities, (e.g., violent acts between individuals in the owner controlled area).February 2016176EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryExelon NuclearCalvert Cliffs AnnexCCNPP Basis Reference(s):1. NEI 99-01 HS3February 2016177EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCnlvert Cliffs AnnexI-xAlnn N~mlA~r.... ............... m m Category:H -Hazards and Other Conditions Affecting Plant SafetySubcategory: 6 -JudgmentInitiating Condition: Other conditions exist that in the judgment of the EmergencyDirector warrant declaration of a General EmergencyEAL:HG6.1 General EmergencyOther conditions exist which in the judgment of the Emergency Director indicate thatevents are in progress or have occurred which involve:Actual or IMMINENT substantial core degradation or melting with potential for loss ofContainment integrityORHOSTILE ACTION that results in an actual loss of physical control of the facility.Releases can be reasonably expected to exceed EPA Protective Action Guidelineexposure levels (1,000 mRem TEDE and 5,000 mRem thyroid CDE) offsite for more thanthe immediate site areaMode Applicability:AllBasis:GenericThis EAL addresses unanticipated conditions not addressed explicitly elsewhere but that warrantdeclaration of an emergency because conditions exist which are believed by the EmergencyDirector to fall under the emergency classification level description for General Emergency.Plant-SpecificDefinitions:Hostile ActionAn act toward CCNPP or its personnel that includes the use of violent force to destroyequipment, take hostages, and/or intimidate the licensee to achieve an end. This includesattack by air, land, or water using guns, explosives, projectiles, vehicles, or other devices usedto deliver destructive force. Other acts that satisfy the overall intent may be included.Hostile Action should not be construed to include acts of civil disobedience or felonious actsthat are not part of a concerted attack on CCNPP. Non-terrorism-based EALs should be usedto address such activities, (e.g., violent acts between individuals in the owner controlled area).February 2016178EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearImminentMitigation actions have been ineffective, additional actions are not expected to be successful,and trended information indicates that the event or condition will occur. Where imminenttimeframes are specified, they shall apply.CCNPP Basis Reference(s):1. NEI 99-01 HG2February 2016179EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory S -System MalfunctionEAL Group: Hot Conditions (RCS temperature > 2000F); EALsin this category are applicable only in one or morehot operating modes. Numerous system-relatedequipment failure events that warrant emergency classification have been identified in thiscategory. They may pose actual or potential threats to plant safety.The events of this category pertain to the following subcategories:1. Loss of AC PowerLoss of emergency plant electrical power can compromise plant safety system operabilityincluding decay heat removal and emergency core cooling systems which may be necessary toensure fission product barrier integrity. This category includes loss of onsite and offsite powersources for the 4 kV safeguard buses.2. Loss of DC PowerLoss of emergency plant electrical power can compromise plant safety system operabilityincluding decay heat removal and emergency core cooling systems which may be necessary toensure fission product barrier integrity. This category includes loss of power to the 125 VDCbuses.3. Criticality & RPS FailureInadvertent criticalities pose potential personnel safety hazards as well being indicative oflosses of reactivity control.Events related to failure of the Reactor Protection System (RPS) to initiate and completereactor trips. In the plant licensing basis, postulated failures of the RPS to complete a reactortrip comprise a specific set of analyzed events referred to as Anticipated Transient WithoutScram (ATWS) events. For EAL classification however, ATWS is intended to mean any tripfailure event that does not achieve reactor shutdown. If RPS actuation fails to assure reactorshutdown, positive control of reactivity is at risk and could cause a threat to fuel clad, RCS andContainment integrity.February 2016 180 EP-AA-1O11 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclear4. Inability to Reach or Maintain Shutdown ConditionsSystem malfunctions may lead to failure of the plant to be brought to the required plantoperating condition required by technical specifications if a limiting condition for operation(LCO) is not met.5. InstrumentationCertain events that degrade plant operator ability to effectively assess plant conditions withinthe plant warrant emergency classification. Losses of annunciators are in this subcategory.6. CommunicationsCertain events that degrade plant operator ability to effectively communicate with essentialpersonnel within or external to the plant warrant emergency classification.7. Fuel Clad DegqradationDuring normal operation, reactor coolant fission product activity is very low. Smallconcentrations of fission products in the coolant are primarily from the fission of tramp uraniumin the fuel clad or minor perforations in the clad itself. Any significant increase from these base-line levels (2% -5% clad failures) is indicative of fuel failures and is covered under Category F,Fission Product Barrier Degradation. However, lesser amounts of clad damage may result incoolant activity exceeding Technical Specification limits. These fission products will becirculated with the reactor coolant and can be detected by coolant sampling and/or the Letdownradiation monitor.8. RCS LeakaqeThe Reactor Vessel provides a volume for the coolant that covers the reactor core. TheReactor Vessel and associated pressure piping (reactor coolant system) together provide abarrier to limit the release of radioactive material should the reactor fuel clad integrity fail.Excessive RCS leakage greater than Technical Specification limits are utilized to indicatepotential pipe cracks that may propagate to an extent threatening fuel clad, RCS andContainment integrity.February 2016 181 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory: S -System MalfunctionSubcategory: 1 -Loss of AC PowerInitiating Condition: Loss of all offsite AC power to 4kV vital buses for_> 15 min.EAL:SUI.I Unusual EventLoss of all offsite AC power, Table S-I, to 4kV vital buses 11(21) and 14(24) for >_ 15 min.(Note 4)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time,Table S-I AC Power Sources* 1(2)A DG*) 1(2)B DG* 0C DG, if aligned* 500kV transmission line 5051** 500kV transmission line 5052** 500kV transmission line 5072*o

• SMECO line ,if aligned* A credited 500kV line must have anindependent 13kV service transformerMode Applicability:1 -Power Operation, 2 -Basis:GenericStartup, 3 -Hot Standby, 4 -Hot ShutdownProlonged loss of off-site AC power reduces required redundancy and potentially degrades thelevel of safety of the plant by rendering the plant more vulnerable to a complete loss of AC powerto emergency busses.Fifteen minutes was selected as a threshold to exclude transient or momentary losses of off-sitepower.February 2016182EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearPlant-SpecificCCNPP essential buses are 4kV vital buses 11 (21) and 14(24). There are five offsite powersources available to these buses:* Three 500kV transmission lines (Lines 5051, 5052, and 5072) supply offsite power to the500kV switchyard via the transmission network.*One 69kV/I13kV Southern Maryland Electric Cooperative (SMECO) line may be manuallyconnected to either 13kV bus and then to the 4kV vital buses. Under certain operationalconditions, 13kV bus(es) may be receiving power from SMECO or may be quicklyconnected to the SMECO tie-line. The SMECO line is not used to carry loads for anoperating unit and may provide power to no more than two 4kV vital buses simultaneously.*If a fault affects only one unit, power may be obtained from the 500kV supply of theunaffected unit through a single 13kV transformer. This is considered an offsite AC powersource available to the affected unit.Based on operational experience, if the SMECO line or the 0C DG is not already aligned, thesecannot be considered available/capable of supplying the bus due to the time it will take to alignthem. In any case, if this cannot be accomplished within 15 minutes, they are not available and anUnusual Event must be declared.In-house power is fed back from the 500kV ring bus through 2 13kV transformers (designated P-13000-1 and P-I13000-2). Normally P-I13000-1 supplies all of Unit -I (except 14 4kV bus) and 214kV bus. P-I13000-2 supplies all of Unit-2 (except 21 4kV bus) and 14 4kV bus. Either P-I13000 iscapable of supplying all loads on both Units.The fifteen-minute interval was selected as a threshold to exclude transient power losses.CCNPP Basis Reference(s):I. UFSAR Section 8 and Figure 8-12. Technical Specifications LCO 3.8.1 AC Sources-Operating3. Technical Specifications LCO 3.8.9 Distribution Systems-Operating4. STP-O-90 AC Sources and On-site Power Distribution Systems 7 Day Operability Verification5. EOP-2 Loss of Off-site Power6. NEI 99-01 SU1February 2016 183 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryC.al,~rt AnnoyFvI:= nn NI~ rl~r5 VlmilV RliliturA b4qkVlVll Category:Subcategory:Initiating Condition:S -System Malfunction1 -Loss of AC PowerAC power capability to 4kV vital buses reduced to a single powersource for _15 mmn. such that ANY additional single failure wouldresult in a complete loss of all 4kV vital bus powerEAL:SAI.1 AlertAC power capability to 4kV vital buses 11(21) and 14(24) reduced to a single powersource, Table S-1, for_> 15 min. (Note 4)ANDANY additional single power source failure will result in a complete loss of all 4kV vital buspowerNote 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time.Table S-I AC Power Sources* 1(2)A DG*0 1(2)B DGa 0C DG, if aligned* 500kV transmission line 5051** 500kV transmission line 5052** 500kV transmission line 5072*o

• SMECO line, if aligned* A credited 500kV line must have anindependent 13kV service transformerMode Applicability:I -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericThe condition indicated by this EAL is the degradation of the off-site and on-site AC power systemssuch that any additional single failure would result in a complete loss of 4kV vital bus AC power toone or both units. This condition could occur due to a loss of off-site power with a concurrent failureFebruary 2016184EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearof all but one emergency generator to supply power to its emergency busses. Another relatedcondition could be the loss of all off-site power and loss of on-site emergency generators with onlyone train of 4kV vital busses being backfed from the unit main generator, or the loss of on-siteemergency generators with only one train of 4kV vital busses being backfed from off-site power.The subsequent loss of this single power source would escalate the event to a Site AreaEmergency in accordance with EAL SS 1.1.Fifteen minutes was selected as a threshold to exclude transient or momentary losses of power.Plant-SpecificCCNPP essential buses are 4kV vital buses 11(21) and 14(24). There are five offsite powersources available to these buses:*Three 500kV transmission lines (Lines 5051, 5052, and 5072) supply offsite power to the500kV switchyard via the transmission network.*One 69kV/i13kV Southern Maryland Electric Cooperative (SMECO) line may be manuallyconnected to either 13kV bus and then to the 4kV vital buses. Under certain operationalconditions, 13kV bus(es) may be receiving power from SMECO or may be quicklyconnected to the SMECO tie-line. The SMECO line is not used to carry loads for anoperating unit and may provide power to no more than two 4kV vital buses simultaneously.*If a fault affects only one unit, power may be obtained from the 500kV supply of theunaffected unit through a single 13 kV transformer. This is considered an offsite AC powersource available to the affected unit.Based on operational experience, if the SMECO line or the OC DG is not already aligned, thesecannot be considered available/capable of supplying the bus due to the time it will take to alignthem. In any case, if this cannot be accomplished within 15 minutes, they are not available and theappropriate emergency classification must be declared.In-house power is fed back from the 500kV ring bus through 2 13kV transformers (designated P-13000-i and P-I13000-2). Normally P-i13000-1 supplies all of Unit -I (except 14 4KV bus) and 214kV bus. P-I13000-2 supplies all of Unit-2 (except 21 4kV bus) and 14 4kV bus. Either P-I13000 iscapable of supplying all loads on both Units.February 2016 185 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearThere are five onsite AC power sources:* 1ADGforbusll* lB DG for busl14* 2A DG for bus 2l* 2B DG for bus 24* OC DG may be aligned to any vital 4kV bus on either unit.The fifteen-minute interval was selected as a threshold to exclude transient power losses. If thecapability for multiple sources to energize the unit vital buses within 15 minutes is not restored, anAlert is declared under this EAL. The subsequent loss of the single remaining power sourceescalates the event to a Site Area Emergency under EAL SS1.l.CCNPP Basis Reference(s):1. UFSAR Section 8 and Figure 8-12. Technical Specifications LOCO 3.8.1 AC Sources-Operating3. Technical Specifications LCO 3.8.9 Distribution Systems-Operating4. OI-21A-1 1A Diesel Generator5. OI-21A-2 2A Diesel Generator6. OI-21B-1 lB Diesel Generator7. 0I-21 B-2 2B Diesel Generator8. 0I-21C 0C Diesel Generator9. STP-O-90 AC Sources and On-site Power Distribution Systems 7 Day Operability Verification10. AOP-71 Loss of 4kV, 480 Volt, or 208/1 20 Volt Instrument Bus Power11. AOP-3F Loss of Off-site Power While in MODES 3, 4, 5, or 612. EOP-0 Post-trip Immediate Actions13. EOP-2 Loss of Off-site Power14. EOP-7 Station Blackout15. EOP-8 Functional Recovery16. NEI 99-01 SA5February 2016 186 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Su bcateg ory:S -System Malfunction1 -Loss of AC PowerInitiating Condition: Loss of all offsite and all onsite AC power to 4kV vital buses for >15 min.EAL:SS1.1 Site Area EmergencyLoss of all offsite and all onsite AC power, Table S-I, to 4kV vital buses 11(21) and 14(24)for> 15 min. (Note 4)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time.Table S-1 AC Power Sources* 1(2)A DGCo

• 1(2)B DG0 OC DG ,if aligned* 500kV transmission line 5051"* 500kV transmission line 5052**l= 500kV transmission line 5072*O

• SMECO line ,if aligned* A credited 500kV line must have anindependent 13kV service transformerMode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericLoss of all AC power to emergency busses compromises all plant safety systems requiring electricpower including RHR, ECCS, Containment Heat Removal and the Ultimate Heat Sink. Prolongedloss of all AC power to 4kV vital busses will lead to loss of Fuel Clad, RCS, and Containment, thusthis event can escalate to a General Emergency.Fifteen minutes was selected as a threshold to exclude transient or momentary losses of off-sitepower.February 2016187EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearEscalation to General Emergency is via EALs in Category F or EAL SG1 .1.Plant-SpecificThe CCNPP vital buses are 4kV buses 11 (21) and 14(24). There are five offsite power sourcesavailable to these buses:*Three 500kV transmission lines (Lines 5051, 5052, and 5072) supply offsite power to the500kV switchyard via the transmission network.*One 69kV/I13kV Southern Maryland Electric Cooperative (SMECO) line may be manuallyconnected to either vital 13kV bus and then to the 4kV vital buses. Under certainoperational conditions, 13kV bus(es) may be receiving power from SMECO or may bequickly connected to the SMECO tie-line. The SMECO line is not used to carry loads for anoperating unit and may provide power to no more than two 4kV vital buses simultaneously.*If a fault affects only one unit, power may be obtained from the 500kV supply of theunaffected unit through a single 13kV transformer. This is considered an offsite AC powersource available to the affected unit.In-house power is fed back from the 500kV ring bus through 2 13kV transformers (designated P-13000-1 and P-I13000-2). Normally P-13000-l supplies all of Unit -I (except 14 4kV bus) and 214kV bus. P-I13000-2 supplies all of Unit-2 (except 21 4kV bus) and 14 4kV bus. Either P-I13000 iscapable of supplying all loads on both Units.There are five onsite AC power sources:* 1A DG for bus11* 1B DG for busI14* 2A DG for bus 21* 2B DG for bus 24* OC DG may be aligned to any vital 4kV bus on either unit.Based on operational experience, if the SMECO line or the OC DG is not already aligned, thesecannot be considered available/capable of supplying the bus due to the time it will take to alignthem. In any case, if this cannot be accomplished within 15 minutes, they are not available and aSite Area Emergency must be declared.February 2016 188 EP-AA-1011 Addendum 3(Revision I)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearConsideration should be given to operable loads necessary to remove decay heat or provideReactor Vessel makeup capability when evaluating loss of all AC power to vital buses. Eventhough an essential bus may be energized, if necessary loads (i.e., loads that if lost would inhibitdecay heat removal capability or Reactor Vessel makeup capability) are not operable on theenergized bus then the bus should not be considered operable.The fifteen-minute interval was selected as a threshold to exclude transient power losses. If the 00DG is available but is not powering a vital bus within 15 minutes, the EAL remains applicable.CCNPP Basis Reference(s):1. UFSAR Section 8 and Figure 8-12. Technical Specifications LCO 3.8.1 AC Sources-Operating3. Technical Specifications LCO 3.8.9 Distribution Systems-Operating4. OI-21A-1 IA Diesel Generator5. Ol-21A-2 2A Diesel Generator6. Ol-21B-1 lB Diesel Generator7. OI-218-2 2B Diesel Generator8. OI-21C 00 Diesel Generator9. STP-O-90 AC Sources and On-site Power Distribution Systems 7 Day Operability Verification10. AOP-71 Loss of 4kV, 480 Volt, or 208/1 20 Volt Instrument Bus Power11. AOP-3F Loss of Off-site Power While in MODES 3, 4, 5, or 612. EOP-0 Post-trip Immediate Actions13. EOP-2 Loss of Off-site Power14. EOP-7 Station Blackout15. EOP-8 Functional Recovery16. NEI 99-01 SS1February 2016 189 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:S -System MalfunctionSubcategory: 1 -Loss of PowerInitiating Condition: Prolonged loss of all offsite and all onsite AC power to 4kV vitalbusesEAL:SGI.1 General EmergencyLoss of all offsite and all onsite AC power, Table S-I, to 4kV vital buses 11(21) and 14(24)AND EITHER:Restoration of at least one 4kV vital bus within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> is not likelyORGET readings > 700°FTable S-I AC Power Sourceso 1(2)A DGU,

• 1(2)B DGe 00 DG, if alignedo500kV transmission line 5051*e, 500kV transmission line 5052*C,' o 500kV transmission line 5072*O e, SMECO line, if aligned* A credited 500kV line must have anindependent 13kV service transformerMode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericLoss of all AC power to emergency busses compromises all plant safety systems requiring electricpower including RHR, EGGS, Containment Heat Removal and the Ultimate Heat Sink. Prolongedloss of all AC power to emergency busses will lead to loss of fuel clad, RCS, and Containment,thus warranting declaration of a General Emergency.February 2016190EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearThis EAL is specified to assure that in the unlikely event of a prolonged loss of all AC power to vital4kV buses, timely recognition of the seriousness of the event occurs and that declaration of aGeneral Emergency occurs as early as is appropriate, based on a reasonable assessment of theevent trajectory.The likelihood of restoring at least one vital bus should be based on a realistic appraisal of thesituation since a delay in an upgrade decision based on only a chance of mitigating the event couldresult in a loss of valuable time in preparing and implementing public protective actions.In addition, under these conditions, fission product barrier monitoring capability may be degraded.Plant-SpecificThe CCNPP vital buses are 4kV buses 11 (21) and 14(24). There are five offsite power sourcesavailable to these buses:* Three 500kV transmission lines (Lines 5051, 5052, and 5072) supply offsite power to the500kV switchyard via the transmission network.*One 69kV/1 3kV Southern Maryland Electric Cooperative (SMECO) line may be manuallyconnected to either vital 13kV bus and then to the 4kV vital buses. Under certainoperational conditions, 13kV bus(es) may be receiving power from SMECO or may bequickly connected to the SMECO tie-line. The SMECO line is not used to carry loads for anoperating unit and may provide power to no more than two 4kV vital buses simultaneously.*If a fault affects only one unit, power may be obtained from the 500kV supply of theunaffected unit through a single 13kV transformer. This is considered an offsite AC powersource available to the affected unit.In-house power is fed back from the 500kV ring bus through 2 13kV transformers (designated P-13000-1 and P-i13000-2). Normally P-I13000-1 supplies all of Unit -I (except 14 4kV bus) and 214kV bus. P-13000-2 supplies all of Unit-2 (except 21 4kV bus) and 14 4kV bus. Either P-I13000 iscapable of supplying all loads on both Units.There are five onsite AC power sources:* 1A DG for bus11* 1B DG for bus14* 2A DG for bus 21* 2B DG for bus 24February 2016 191 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclear* 00 DG may be aligned to any vital 4kV bus on either unit.Consideration should be given to operable loads necessary to remove decay heat or provideReactor Vessel makeup capability when evaluating loss of all AC power to vital buses. Eventhough a vital bus may be energized, if necessary loads (i.e., loads that if lost would inhibit decayheat removal capability or Reactor Vessel makeup capability) are not operable on the energizedbus then the bus should not be considered operable.CCNPP is licensed both for a four hour SBO coping category and a one hour 580 copingcategory. The ability of each unit to cope with a four hour 580 duration was based on anassessment of condensate inventory required for decay heat removal, Class 1 E battery capacity,compressed air availability or manual operation of certain valves, effects of loss of ventilation,Containment isolation valve operability, and reactor coolant inventory loss. A plant-specific analysisindicates that the expected rates of reactor coolant inventory loss under 5B0 conditions do notresult in core uncovery in a 5B0 for four hours. Therefore, makeup systems in addition to thosecurrently available under 5B0 conditions are not required to maintain core cooling under naturalcirculation (including reflux cooling). Thus, conditions in which restoration of AC power within fourhours is not likely are included in the EAL.Installation of the SBO diesel allowed CCNPP to operate as a plant having a one hour copingcapability. This allowance is in recognition that sufficient diesel generator back-up reduces thelikelihood of station blackout. The analysis for the four hour coping category however, provides thesource of the appropriate estimate of the time to core uncovery following 580 from which the plantcannot recover. This time (four hours) is therefore used as the basis for determining when todeclare a General Emergency subsequent to a prolonged 580.Core Exit Thermocouples (CETs) are a component of the Inadequate Core CoolingInstrumentation and provide an indirect indication of fuel clad temperature by measuring thetemperature of the reactor coolant that leaves the core region. A superheat condition is indicatedby CET readings above 700°F. The RCS Pressure Safety Limit is 2750 psia per CCNPP TechnicalSpecifications. The saturation temperature for this pressure is 682.2°F. Per Action Value BasesDocument EOP-24.33, the uncertainty on CET Temperature is +/- 39.8°F. If one or more CETsindicate 7220F (682.2 + 39.8), subcooling has been lost for at least some locations in the core.CET indications at or above 7220°F are a clear sign that core heat removal capability is lost orgreatly reduced and one fission product barrier, the fuel clad, is threatened due to elevated fuelFebruary 2016 192 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nucleartemperatures. 700°F qualifies as a condition representing a potential loss of the fuel clad barrier(ref. 16).CCNPP Basis Reference(s):1. UFSAR Section 8 and Figure 8-12. Technical Specifications LCO 3.8.1 AC Sources-Operating3. Technical Specifications LCO 3.8.9 Distribution Systems-Operating4. OI-21lA-I 1A Diesel Generator5. Ol-21A-2 2A Diesel Generator6. OI-21B-I lB Diesel Generator7. OI-21B-2 2B Diesel Generator8. Ol-21C OC Diesel Generator9. STP-~O-90 AC Sources and On-site Power Distribution Systems 7 Day Operability Verification10. AOP-71 Loss of 4kV, 480 Volt, or 208/1 20 Volt Instrument Bus Power11. AOP-3F Loss of Off-site Power While in MODES 3, 4, 5, or 612. EOP-0 Post-trip Immediate Actions13. EOP-2 Loss of Off-site Power14. EOP-7 Station Blackout15. EOP-8 Functional Recovery16. EOP-24.33 Action Value Bases Document17. ERPIP-800 Core Damage Assessment18. ERPIP-802 Core Damage Assessment Using Core Exit Thermocouples19. EOP-5 Loss of Coolant Accident20. CEN-152 Emergency Procedure Guidelines21. OP-7 Shutdown Operations22. ERPIP-601 Severe Accident Management Initial Diagnosis23. Letter dated March 6, 1997 from Charles H. Cruse to USNRC "Revision to Emergency ActionLevels Technical Basis Document"24. NEI 99-01 SGIFebruary 2016 193 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: S -System MalfunctionSubcategory: 2 -Loss of DC PowerInitiating Condition: Loss of all vital DC power for> 15 min.EAL:SS2.1 Site Area Emergency< 105 VDC on all 125 VDC buses (11, 12, 21 and 22) for _ 15 min. (Note 4)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable time.Mode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericLoss of all DC power compromises ability to monitor and control plant safety functions. Prolongedloss of all DC power will cause core uncovering and loss of Containment integrity when there issignificant decay heat and sensible heat in the reactor system.Fifteen minutes was selected as a threshold to exclude transient or momentary power losses.Escalation to a General Emergency would occur by EALs in Category R and Category F.Plant-SpecificThe 125 VDC vital system is divided into four independent and isolated channels. Each channelconsists of one battery, two battery chargers, one DC bus, multiple DC unit control panels, and twoinverters. Each inverter has an associated vital AC distribution panel board. Power to the DC bus,DC unit control panels, and inverters is supplied by the station batteries and/or the batterychargers. Each battery charger is fully rated and can recharge a discharged battery while at thesame time supplying the steady state power requirements of the system. A reserve 125 VDCsystem for the plant is completely independent and isolated from all four separation groups, yet iscapable of replacing any of the 125 VDC batteries. This system consists of one battery, one batterycharger, and the associated DC switching equipment. Only the battery may be transferred forreplacement duty.The safety-related station batteries have been sized to carry their expected shutdown loadsfollowing a plant trip/LOCA and loss of offsite power or following a station blackout without batteryFebruary 2016 194 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearterminal voltage falling below 105 volts. The loss of the 1A Diesel Generator 125 VDC bus 14 or0C Diesel Generator bus 16 does not constitute an entry condition for this EAL.This EAL is the hot condition equivalent of the cold condition loss of DC powerEAL CU2.1.CCNPP Basis Reference(s):1. UFSAR Section 8.4.3 and Figure 8.92. EOP-0 Post-Trip Immediate Actions3. EOP-2 Loss of Off-Site Power, Section V4. AOP-7J Loss of 120 Volt Vital AC or 125 Volt Vital DC Power5. Technical Specifications Bases 3.8.46. NEI 99-01 SS3February 2016195EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:S -System Malfunction3 -Criticality & RPS FailureInitiating Condition: Inadvertent criticalityEAL:SU3.1 Unusual EventAn UNPLANNED sustained positive startup rate observed on nuclear instrumentationMode Applicability:3 -Hot Standby, 4 -Hot ShutdownBasis:GenericThis EAL addresses inadvertent criticality events. While the primary concern of this EAL iscriticality This EAL addresses inadvertent criticality events. This EAL indicates a potentialdegradation of the level of safety of the plant, warranting a UE classification. This EAL excludesinadvertent criticalities that occur during planned reactivity changes associated with reactorstartups (e.g., criticality earlier than estimated).Escalation would be by EALs in Category F, as appropriate to the operating mode at the time ofthe event.Plant-SpecificThe term "sustained" is used to allow exclusion of expected short-term positive startup rates fromplanned fuel bundle or control rod movements during core alteration. These short-term positivestartup rates are the result of the rise in neutron population due to subcritical multiplication.Definitions:UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.CCNPP Basis Reference(s):1. UFSAR Section 7.5.22. 1C05-ALM Reactivity Control Alarm Manual, Window D-05, D-153. AOP-1A Inadvertent Boron Dilution4. NEI 99-01 SU8February 2016196EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategoary:S -System Malfunction3 -Criticality & RPS FailureInitiating Condition: Automatic trip failed to shut down the reactor and the manualactions taken from the reactor control console are successful inshutting down the reactorEAL:SA3.1 AlertAn automatic reactor trip failed to shut down the reactorANDManual actions taken at the Control Room panels successfully shut down the reactor asindicated by reactor power < 5%Mode Applicability:1 -Power OperationBasis:Generic-The reactor should be considered shutdown when it producing less heat than the maximum decayheat load for which the safety systems are designed (5% power).Manual trip actions taken at the Control Room panels are any set of actions by the reactoroperator(s) which causes or should cause control rods to be rapidly inserted into the core andshuts down the reactor.This condition indicates failure of the automatic protection system to trip the reactor. This conditionis more than a potential degradation of a safety system in that a front line automatic protectionsystem did not function in response to a plant transient. Thus the plant safety has beencompromised because design limits of the fuel may have been exceeded. An Alert is indicatedbecause conditions may exist that lead to potential loss of fuel clad barrier or RCS barrier andbecause of the failure of the Reactor Protection System to automatically shut down the plant.If manual actions taken at the reactor control console fail to shut down the reactor, the event wouldescalate to a Site Area Emergency.Plant-SpecificFollowing a successful reactor trip, nuclear power promptly drops to about six percent of theoriginal power level and then decays to a level some 8 decades less at a startup rate (SUR) ofabout (-)1/3 DPM. The reactor power drop continues until reactor power reaches the point at whichthe influence of source neutrons on reactor power starts to be observable. A predictable post-tripFebruary 2016197EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearresponse from an automatic reactor trip signal should therefore consist of a prompt drop in reactorpower as sensed by the nuclear instrumentation (NI) and a negative SUR as nuclear power dropsinto the source range.The RPS setpoints listed in Figure S-i should result in an automatic reactor trip:Figure S-I Automatic RPS TripsREACTOR TRIPHigh Power Level 2/4 VariableHigh Rate-of-Change of Power 2/4 below 15% Pwr 2.6 decade/mmn.Low Reactor Coolant Flow 2/4 above 10-4% Pwr VariableLow Steam Generator Pressure 2/4 670 psi9Low Steam Generator Water Level 2/4 10 in. below top of feed ringHigh Pressurizer Pressure 2/4 2385 psigThermal Margin/Low Pressure 2/4 above 10-4% Pwr VariableLoss of Load 2/4 above 15% Pwr N/AHigh Containment Pressure 2/4 4 psi9Axial Flux Offset 2/4 VariableThermal Margin/SG Press. Duff. Hi 2/4 above 10-4% Pwr 135 psidPer FOP-a, Post-Trip Immediate Actions, the operator ensures that the reactor has tripped bydepressing one set of Manual Reactor Trip buttons immediately following any symptoms of areactor trip. The symptoms include:* Reactor Trip alarm* Control Element Assembly (CEA) Circuit Breaker(s) Trip alarms* Rapid Lowering in Reactor Power* Protection Channel Trip alarm* Reactor Protective System (RPS) Trip Bistable Lights litFollowing depression of the reactor trip buttons, the operator verifies that reactor power isdecreasing. If these responses cannot be verified, as part of contingency actions, the operator isinstructed to open the motor generator (MG) set feeder breakers that provide power to the ControlElement Drive Mechanism (CEDM).If reactor power is above 5%, the reactor is producing more heat than the Auxiliary Feedwatersystem and Atmospheric Dump Valves are designed to remove (ref. 6, 7, 8). The Alert emergencyclassification is required whenever the Shift Manager determines that a required automatic reactortrip did not succeed in reducing reactor power to 5% or lower. It is recognized that EOP-O instructsthe operator to depress the manual trip buttons whether or not a required automatic reactor tripactually occurred. However, the failure of the RPS to complete a reactor trip that reduced reactorFebruary 2016 198 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclearpower to 5% or lower following receipt of an automatic trip signal meets the Alert classificationthreshold of potential substantial degradation in the level of safety of the plant. This is true even ifno radiation alarms indicate fuel problems.In the event that the operator identifies a reactor trip is imminent and successfully initiates amanual reactor trip before the automatic trip setpoint is reached, no declaration is required. Thesuccessful manual trip of the reactor before it reaches its automatic trip setpoint or reactor tripsignals caused by instrumentation channel failures do not lead to a potential fission product barrierloss. If manual reactor trip actions at the Control Room panels (following an unsuccessfulautomatic reactor trip) fail to reduce reactor power to or below 5%, the event escalates to the SiteArea Emergency under EAL SS3.1.CCNPP Basis Reference(s):1. Technical Specifications 3.3.1, Reactor Protective System (RPS) Instrumentation -Operating2. Technical Specifications 3.3.2, Reactor Protective System (RPS) Instrumentation -Shutdown3. Technical Specifications 3.3.3, Reactor Protective System (RPS) Logic and Trip Initiation4. EOP-O Post-Trip Immediate Actions5. UFSAR Section 76. AOP-3G Malfunction of Main Feedwater System7. UFSAR 14.1.2.2.e8. UFSAR 14.4.1 & Table 14.1-29. NEI 99-01 SA2February 2016199EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:S -System Malfunction3 -Criticality & RPS FailureInitiating Condition: Automatic trip and manual actions taken from the reactor controlconsole failed to shut down the reactorEAL:SS3.1 Site Area EmergencyAn automatic reactor trip failed to shut down the reactor as indicated by reactor power >5%ANDManual actions taken at the Control Room panels do not shut down the reactor asindicated by reactor power > 5%Mode Applicability:1 -Power OperationBasis:GenericUnder these conditions, the reactor is producing more heat than the maximum decay heat load forwhich the safety systems are designed and efforts to bring the reactor subcritical are unsuccessful.A Site Area Emergency is warranted because conditions exist that lead to imminent loss orpotential loss of both fuel clad and RCS.The reactor should be considered shutdown when it producing less heat than the maximum decayheat load for which the safety systems are designed (5% power).Manual scram (trip) actions taken at the Control Room panels are any set of actions by the reactoroperator(s) at which causes or should cause control rods to be rapidly inserted into the core andshuts down the reactor.Manual trip actions are not considered successful if action away from the Control Room panels isrequired to trip the reactor. This EAL is still applicable even if actions taken away from the ControlRoom panels are successful in shutting the reactor down because the design limits of the fuel mayhave been exceeded or because of the gross failure of the Reactor Protection System to shutdownthe plant.Escalation of this event to a General Emergency would be due to a prolonged condition leading toan extreme challenge to either core-cooling or heat removal.February 2016200EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearPlant-SpecificFollowing a successful reactor trip, nuclear power promptly drops to about six percent of theoriginal power level and then decays to a level some 8 decades less at a startup rate (SUR) ofabout (-)I/3 DPM. The reactor power drop continues until reactor power reaches the point at whichthe influence of source neutrons on reactor power starts to be observable. A predictable post-tripresponse from an automatic reactor trip signal should therefore consist of a prompt drop in reactorpower as sensed by the nuclear instrumentation (NI) and a negative SUR as nuclear power dropsinto the source range.The RPS setpoints listed in Figure S-I should result in an automatic reactor trip:Figure S-I Automatic RPS TripsREACTOR TRIPHigh Power LevelHigh Rate-of-Change of PowerLow Reactor Coolant FlowLow Steam Generator PressureLow Steam Generator Water LevelHigh Pressurizer PressureThermal Margin/Low PressureLoss of LoadHigh Containment PressureAxial Flux OffsetThermal Margin/SG Press. Duff. Hi2/42/4 below 15% Pwr2/4 above 10-4% Pwr2/42/42/42/4 above 10-4% Pwr2/4 above 15% Pwr2/42/42/4 above 10-4% PwrVariable2.6 decade/min.Variable670 psig10 in. below top of feed ring2385 psigVariableN/A4 psigVariable135 psidPer EOP-0, Post-Trip Immediate Actions, the operator ensures that the reactor has tripped bydepressing one set of Manual Reactor Trip buttons immediately following any symptoms of areactor trip. The symptoms include:* Reactor Trip alarm* Control Element Assembly (CEA) Circuit Breaker(s) Trip alarms* Rapid Lowering in Reactor Power* Protection Channel Trip alarm* Reactor Protective System (RPS) Trip Bistable Lights litFollowing depression of the reactor trip buttons, the operator verifies that reactor power isdecreasing. If these responses cannot be verified, as part of contingency actions, the operator isinstructed to open the motor generator (MG) set feeder breakers that provide power to the ControlElement Drive Mechanism (CEDM).February 2016201EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearIf reactor power is above 5%, the reactor is producing more heat than the Auxiliary Feedwatersystem and Atmospheric Dump Valves are designed to remove (ref. 7, 8, 9). Fast boration is thusrequired and there is an actual major failure of a system intended for protection of the public. Thecombination of failure of both front line and backup protection systems to function in response to aplant transient, along with the continued production of heat poses a direct threat to the Fuel Cladand RCS barriers and warrants declaration of a Site Area Emergency.CCNPP Basis Reference(s):1. Technical Specifications 3.3.1, Reactor Protective System (RPS) Instrumentation -Operating2. Technical Specifications 3.3.2, Reactor Protective System (RPS) Instrumentation -Shutdown3. Technical Specifications 3.3.3, Reactor Protective System (RPS) Logic and Trip Initiation4. EOP-O Post-Trip Immediate Actions5. EOP-8 Functional Recovery6. UFSAR Section 77. AOP-3G Malfunction of Main Feedwater System8. UFSAR 14.1.2.2.e9. UFSAR 14.4.1 & Table 14.1-210. NEI 99-01 SS2February 2016202EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCliffs Annexl:vY-Inn Mi irl,-rCategory:S -System MalfunctionSubcategory: 3 -Criticality & RPS FailureInitiating Condition: Automatic trip and all manual actions fail to shut down the reactorand indication of an extreme challenge to the ability to cool thecore existsEAL:SG3.1 General EmergencyAn automatic reactor trip failed to shut down the reactor as indicated by reactor power >5%ANDAll manual actions fail to shut down the reactor as indicated by reactor power > 5%ANDANY of the following exist or have occurred:* CET readings > 700°F* RCS pressure > PORV setpoint* RCS subcooling < 250FMode Applicability:1 -Power OperationBasis:GenericUnder these conditions, the reactor is producing more heat than the maximum decay heat load forwhich the safety systems are designed and efforts to bring the reactor subcritical are unsuccessful.The reactor should be considered shutdown when it producing less heat than the maximum decayheat load for which the safety systems are designed (5% power). In the event either of thesechallenges exists at a time that the reactor has not been brought below the power associated withthe safety system design a core melt sequence exists. In this situation, core degradation can occurrapidly. For this reason, the General Emergency declaration is intended to be anticipatory of thefission product barrier table declaration to permit maximum off-site intervention time.Plant-SpecificFollowing a successful reactor trip, nuclear power promptly drops to about six percent of theoriginal power level and then decays to a level some 8 decades less at a startup rate (SUR) ofabout (-)1/3 DPM. The reactor power drop continues until reactor power reaches the point at whichFebruary 2016203EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuclearthe influence of source neutrons on reactor power starts to be observable. A predictable post-tripresponse from an automatic reactor trip signal should therefore consist of a prompt drop in reactorpower as sensed by the nuclear instrumentation (NI) and a negative SUR as nuclear power dropsinto the source range.The RPS setpoints listed in Figure S-i should result in an automatic reactor trip:Figure S-I Automatic RPS TripsREACTOR TRIPHigh Power Level 2/4 VariableHigh Rate-of-Change of Power 2/4 below 15% Pwr 2.6 decade/mai.Low Reactor Coolant Flow 2/4 above 10-4% Pwr VariableLow Steam Generator Pressure 2/4 670 psigLow Steam Generator Water Level 2/4 10 in. below top of feed ringHigh Pressurizer Pressure 2/4 2385 psigThermal Margin/Low Pressure 2/4 above 10-4% Pwr VariableLoss of Load 2/4 above 15% Pwr N/AHigh Containment Pressure 2/4 4 psigAxial Flux Offset 2/4 VariableThermal Margin/SG Press. Diff. Hi 2/4 above 10-4% Pwr 135 psidPer EOP-0, Post-Trip Immediate Actions, the operator ensures that the reactor has tripped bydepressing one set of Manual Reactor Trip buttons immediately following any symptoms of areactor trip. The symptoms include:* Reactor Trip alarm* Control Element Assembly (CEA) Circuit Breaker(s) Trip alarms* Rapid Lowering in Reactor Power* Protection Channel Trip alarm* Reactor Protective System (RPS) Trip Bistable Lights litFollowing depression of the reactor trip buttons, the operator verifies that reactor power isdecreasing. If these responses cannot be verified, as part of contingency actions, the operator isinstructed to open the motor generator (MG) set feeder breakers that provide power to the ControlElement Drive Mechanism (CEDM).If reactor power is above 5%, the reactor is producing more heat than the Auxiliary Feedwatersystem and Atmospheric Dump Valves are designed to remove (ref. 7, 8, 9). Fast boration is thusrequired and there is an actual major failure of a system intended for protection of the public. Thecombination of failure of both front line and backup protection systems to function in response to aFebruary 2016 204 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon Nuc:learplant transient, along with the continued production of heat poses a direct threat to the Fuel Cladand RCS barriers.Core Exit Thermocouples (CETs) are a component of the Inadequate Core CoolingInstrumentation system and provide an indirect indication of fuel clad temperature by measuringthe temperature of the reactor coolant that leaves the core region. The RCS Pressure Safety Limitis 2750 psia per CCNPP Technical Specifications. The saturation temperature for this pressure is682.2°F. Per Action Value Bases Document EOP-24.33, the uncertainty on CET Temperature is+/- 39.8°F. If one or more CETs indicate 722°F (682.2 + 39.8), subcooling has been lost for atleast some locations in the core. CET indications at or above 722°F are a clear sign that core heatremoval capability is lost or greatly reduced and one fission product barrier, the fuel clad, isthreatened due to elevated fuel temperatures. 700°F qualifies as a condition representing apotential loss of the fuel clad barrier (ref. 13).Inability to remove heat from the RCS to the ultimate heat sink (bay or atmosphere) is a loss offunction required for hot shutdown with the reactor at pressure and temperature and thusrepresents potential loss of the Fuel Clad and RCS barriers.The combination of these conditions (reactor power greater than 5% with loss of subcooling marginor inability to remove heat from the RCS) indicates the ultimate heat sink function is under extremechallenge, a core melt sequence may exist and rapid degradation of the fuel clad could begin. Topermit maximum offsite intervention time, the General Emergency declaration is appropriate inanticipation of an inevitable General Emergency declaration due to loss and potential loss of fissionproduct barriers.February 2016 205 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclIearCCNPP Basis Reference(s):1. Technical Specifications 3.3.1, Reactor Protective System (RPS) Instrumentation -Operating2. Technical Specifications 3.3.2, Reactor Protective System (RPS) Instrumentation -Shutdown3. Technical Specifications 3.3.3, Reactor Protective System (RPS) Logic and Trip Initiation4. EOP-O Post-Trip Immediate Actions5. EOP-8 Functional Recovery6. UFSAR Section 77. AOP-3G Malfunction of Main Feedwater System8. UFSAR 14.1.2.2.e9. UFSAR 14.4.1 & Table 14.1-210. ERPIP-800 Core Damage Assessment11. ERPIP-802 Core Damage Assessment Using Core Exit Thermocouples12. EOP-5 Loss of Coolant Accident13. EOP-24.33 Action Value Bases Document14. CEN-152 Emergency Procedure Guidelines15. OP-7 Shutdown Operations15. ERPIP-601 Severe Accident Management Initial Diagnosis16. NEI 99-01 SG2February 2016206EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:S ubcategoary:S -System Malfunction4 -Inability to Reach or Maintain Shutdown ConditionsInitiating Condition: Inability to reach required shutdown within Technical SpecificationlimitsEAL:SU4.1 Unusual EventPlant is not brought to required operating mode within Technical Specifications LCOrequired action completion timeMode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericLimiting Conditions of Operation (LCOs) require the plant to be brought to a required operatingmode when the Technical Specification required configuration cannot be restored. Depending onthe circumstances, this may or may not be an emergency or precursor to a more severe condition.In any case, the initiation of plant shutdown required by the site Technical Specifications requires afour hour report under 10 CFR 50.72 (b) Non-emergency events. The plant is within its safetyenvelope when being shut down within the allowable required action completion time in theTechnical Specifications. An immediate UE is required when the plant is not brought to therequired operating mode within the allowable required action completion time in the TechnicalSpecifications. Declaration of a UE is based on the time at which the LCO-specified required actioncompletion time period elapses under the site Technical Specifications and is not related to howlong a condition may have existed.Plant-SpecificNoneCCNPP Basis Reference(s):1. Technical Specifications 3.0, Limiting Conditions for Operations (LCO) Applicability2. NEI 99-01 SU2February 2016207EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Su bcateg ory:S -System Malfunction5 -InstrumentationInitiating Condition: Unplanned loss of safety system annunciation or indication in theControl Room for >_ 15 min.EAL:SU5.1 Unusual EventUNPLANNED loss of greater than approximately 75% of safety system annunciation orindication on Control Room panels for > 15 mmn. (Note 4)determined that the condition has exceeded, or will likely exceed, the applicable timeMode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericThis EAL is intended to recognize the difficulty associated with monitoring changing plantconditions without the use of a major portion of the annunciation or indication equipment.Recognition of the availability of computer based indication equipment is considered."Planned" loss of annunciators or indicators includes scheduled maintenance and testing activities.Quantification is arbitrary, however, it is estimated that if approximately 75% of the safety systemannunciators or indicators are lost, there is an increased risk that a degraded plant condition couldgo undetected. It is not intended that plant personnel perform a detailed count of theinstrumentation lost but use the value as a judgment threshold for determining the severity of theplant conditions.It is further recognized that plant design provides redundant safety system indication powered fromseparate uninterruptible power supplies. While failure of a large portion of annunciators is morelikely than a failure of a large portion of indications, the concern is included in this EAL due todifficulty associated with assessment of plant conditions. The loss of specific, or several, safetysystem indicators should remain a function of that specific system or component operability status.This will be addressed by the specific Technical Specification. The initiation of a TechnicalSpecification imposed plant shutdown related to the instrument loss will be reported via 10OCER50.72. If the shutdown is not in compliance with the Technical Specification action, the UE is basedon EAL SU4.1.Annunciators or indicators for this EAL include those identified in the Abnormal OperatingProcedures, in the Emergency Operating Procedures, and in other EALs (e.g., area, process,and/or effluent rad monitors, etc.).February 2016208EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearFifteen minutes was selected as a threshold to exclude transient or momentary power losses.This UE will be escalated to an Alert based on a concurrent loss of compensatory indications or if asignificant transient is in progress during the loss of annunciation or indication.Plant-SpecificThe Control Room Panels that house safety related annunciators are listed in the table below:Unit 1 Unit 210C04 20041005 20051 C06 200610C07 2C071008 2C0810C09 20091010 20101013 20131C18A 101901C18B 102010 190 1C20A10C22 1C20B1 C24B 10C2210C26 10C2481033 102610C34 10C3310C34Definitions:UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.February 2016209EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCCNPP Basis Reference(s):1. UFSAR Sections 7.6 and 7.72. AOP-7J Loss of 120 Volt Vital AC or 125 Volt Vital DC Power3. UFSAR 7.5.54. Ol-50A Plant Computer5. OP-AA-103-102, Watch Standing Practices6. NEI 99-01 SU3February 2016210EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:S -System Malfunction5 -InstrumentationInitiating Condition: Unplanned loss of safety system annunciation or indication in theControl Room with either (1) a significant transient in progress, or(2) compensatory indicators are unavailableEAL:SA5.1 AlertUNPLANNED loss of greater than approximately 75% of safety system annunciation orindication on Control Room panels for _> 15 min. (Note 4)AND EITHER:A significant transient is in progress, Table S-2ORCompensatory indications are unavailable (Plant Computer, SPDS)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable timeTable S-2 Significant Transients* Automatic turbine runback > 25% thermal power* Electric load rejection > 25% full electrical load* Reactor trip* Safety Injection actuationMode Applicability:I -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericThis EAL is intended to recognize the difficulty associated with monitoring changing plantconditions without the use of a major portion of the annunciation or indication equipment during asignificant transient."Planned" loss of annunciators or indicators includes scheduled maintenance and testing activities.Quantification is arbitrary, however, it is estimated that if approximately 75% of the safety systemannunciators or indicators are lost, there is an increased risk that a degraded plant condition couldgo undetected. It is not intended that plant personnel perform a detailed count of theinstrumentation lost but use the value as a judgment threshold for determining the severity of theplant conditions. It is also not intended that the Shift Manager be tasked with making a judgmentFebruary 2016211EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nucleardecision as to whether additional personnel are required to provide increased monitoring of systemoperation.It is further recognized that most plant designs provide redundant safety system indication poweredfrom separate uninterruptible power supplies. While failure of a large portion of annunciators ismore likely than a failure of a large portion of indications, the concern is included in this EAL due todifficulty associated with assessment of plant conditions. The loss of specific, or several, safetysystem indicators should remain a function of that specific system or component operability status.This will be addressed by the specific Technical Specification. The initiation of a TechnicalSpecification imposed plant shutdown related to the instrument loss will be reported via 10 CFR50.72. If the shutdown is not in compliance with the Technical Specification action, the UE is basedon EAL SU4.1.Annunciators or indicators for this EAL include those identified in the Abnormal OperatingProcedures, in the Emergency Operating Procedures, and in other EALs (e.g., area, process,and/or effluent rad monitors, etc.)."Compensatory indications" in this context includes computer based information such as PlantProcess Computer and SPDS.Fifteen minutes was selected as a threshold to exclude transient or momentary power losses.This Alert will be escalated to a Site Area Emergency if the operating crew cannot monitor thetransient in progress due to a concurrent loss of compensatory indications with a significanttransient in progress during the loss of annunciation or indication.Plant-SpecificPlant Process Computer and SPDS are considered compensatory indication.Significant transients are listed in Table S-2.The Control Room Panels that house safety related annunciators are listed in the table below:Uniti1 Unit 21 C04 2C041C05 2C051 C06 2C061 C07 2C071 C08 2C081 C09 2C091C10 2C101C13 2C131C18A 1CI9CFebruary 2016212EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclear1018B 10201C019C 1C20A10C22 1C20B10C248 1 C2210C26 10C24810C33 10C2610C34 10C3310C34Definitions:UnplannedA parameter change or an event, the reasons for which may be known or unknown, that is notthe result of an intended evolution or expected plant response to a transient.CCNPP Basis Reference(s):1. UFSAR Sections 7.6 and 7.72. AOP-7J Loss of 120 Volt Vital AC or 125 Volt Vital DC Power3. UFSAR 7.5.54. OI-50A Plant Computer5. OP-AA-1 03-102, Watch Standing Practices6. NEI 99-01 SA4February 2016213EP-AA-1 011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:S -System Malfunction5 -InstrumentationInitiating Condition: Inability to monitor a significant transient in progressEAL:SS5.1 Site Area EmergencyLoss of greater than approximately 75% of safety system annunciation or indication onControl Room panels for >_ 15 mai. (Note 4)ANDA significant transient is in progress, Table S-2ANDCompensatory indications are unavailable (Plant Computer, SPDS)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soon as it isdetermined that the condition has exceeded, or will likely exceed, the applicable timeTable S-2 Significant Transients* Automatic turbine runback > 25% thermal power* Electric load rejection > 25% full electrical load* Reactor trip* Safety Injection actuationMode Applicability:I -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericThis EAL is intended to recognize the threat to plant safety associated with the complete loss ofcapability of the Control Room staff to monitor plant response to a significant transient."Planned" and "unplanned" actions are not differentiated since the loss of instrumentation of thismagnitude is of such significance during a transient that the cause of the loss is not anameliorating factor.Quantification is arbitrary, however, it is estimated that if approximately 75% of the safety systemannunciators or indicators are lost, there is an increased risk that a degraded plant condition couldgo undetected. It is not intended that plant personnel perform a detailed count of theinstrumentation lost but use the value as a judgment threshold for determining the severity of theplant conditions. It is also not intended that the Shift Manager be tasked with making a judgmentFebruary 2016214EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nucleardecision as to whether additional personnel are required to provide increased monitoring of systemoperation.It is further recognized that most plant designs provide redundant safety system indication poweredfrom separate uninterruptible power supplies. While failure of a large portion of annunciators ismore likely than a failure of a large portion of indications, the concern is included in this EAL due todifficulty associated with assessment of plant conditions. The loss of specific, or several, safetysystem indicators should remain a function of that specific system or component operability status.This will be addressed by the specific Technical Specification. The initiation of a TechnicalSpecification imposed plant shutdown related to the instrument loss will be reported via 10 CFR50.72. If the shutdown is not in compliance with the Technical Specification action, the NOUE isbased on EAL SU4.1A Site Area Emergency is considered to exist if the Control Room staff cannot monitor safetyfunctions needed for protection of the public while a significant transient is in progress.Annunciators for this EAL are limited to include those identified in the Abnormal OperatingProcedures, in the Emergency Operating Procedures, and in other EALs (e.g. area, process,and/or effluent rad monitors, etc.)Indications needed to monitor safety functions necessary for protection of the public includeControl Room indications, computer generated indications and dedicated annunciation capability."Compensatory indications" in this context includes computer based information such as PlantProcess Computer and SPDS.Fifteen minutes was selected as a threshold to exclude transient or momentary power losses.Plant-SpecificPlant computer and SPDS are considered compensatory indication.Significant transients are listed in Table S-2.The Control RoomPanels that house safety related annunciators are listed in the table below:Unit 1 Unit 21 C04 2C041C05 2C051C06 2C061 C07 2C071C08 2C081C09 2C091C10 2C101C13 2C13February 2016215EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclear1C18A 1C19C1C18B 10201C019C 1C20A1022 1C20B1C24B 102210C26 1 C24B1 C33 10C2610C34 1 C3310C34CCNPP Basis Reference(s):1. UFSAR Sections 7.6 and 7.72. AOP-7J Loss of 120 Volt Vital AC or 125 Volt Vital DC Power3. UFSAR 7.5.54. Ol-50A Plant Computer5. CNG-OP-1 .01-2003 Alarm Response and Control6. NEI 99-01 SS6February 2016216EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Subcategory:S -System Malfunction6 -CommunicationsInitiating Condition: Loss of all onsite or offsite communications capabilitiesEAL:SU6.1 Unusual EventLoss of all Table S-3 onsite (internal) communication methods affecting the ability toperform routine operationsORLoss of all Table S-3 offsite (external) communication methods affecting the ability toperform offsite notifications to any agencyTable S-3 Communications SystemsOnsite OffsiteSystem (internal) (external)Commercial phone system X XPlant page system XFTS 2001 telephone system XCCNPP Radio System XSatellite Phone System XCellular Phone System X XMode Applicability:I -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericThe purpose of this EAL is to recognize a loss of communications capability that either defeats theplant operations staff ability to perform routine tasks necessary for plant operations or the ability tocommunicate issues with off-site authorities.The loss of off-site communications ability is expected to be significantly more comprehensive thanthe condition addressed by 10 CFR 50.72.February 2016217EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearThe availability of one method of ordinary off-site communications is sufficient to inform federal,state, and local authorities of plant problems. This EAL is intended to be used only whenextraordinary means (e.g., relaying of information from non-routine radio transmissions, individualsbeing sent to off-site locations, etc.) are being used to make communications possible.Plant-SpecificOnsite/offsite communications systems are listed in Table S-3 (ref. 1, 2, 3).This EAL is the hot condition equivalent of the cold condition EAL CU5. 1.CCNPP Basis Reference(s):I. UFSAR Section 7.82. Emergency Response Facility Directory & Communications Equipment Information3. NO-I-I113, Control of Radio Transmitter (PRT)4. NEI 99-01 SU6February 2016218EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnAYIExelon Nuc~lear.............. Im IR ................Category: S -System MalfunctionSubcategory: Fuel Clad DegradationInitiating Condition: Fuel clad degradationEAL:SU7.1 Unusual EventCoolant activity > ANY of the following:* Dose equivalent 1-131 0.5 uCi/gm for 100 hrs. continuous* Dose equivalent 1-131 acceptable region of T.S. Fig. 3.4.15-1* Dose equivalent 1-131 137.5 uCifgm* Gross activity 1 00/E-bar uCi/gmMode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericThis EAL is included because it is a precursor of more serious conditions and, as result, isconsidered to be a potential degradation of the level of safety of the plant.Escalation of this EAL to the Alert level is via the EALs in Category F.This threshold addresses coolant samples exceeding coolant technical specifications limits.Plant-SpecificElevated reactor coolant activity represents a potential degradation in the level of safety of theplant and a potential precursor of more serious problems. This EAL addresses reactor coolantsamples exceeding coolant technical specifications (including allowable transient time limitspermitted in the Technical Specifications). Though the referenced Technical Specification limitsare mode dependent, it is appropriate that the EAL be applicable in modes 1-4, as it indicates apotential degradation in the level of safety of the plant.For mode 4, conditions are not governed by the Technical Specification applicability. While inmode 4 however, any abnormal chemistry sample that is reported will be compared to the criteriaFebruary 2016219EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuc~learof this EAL and an Unusual Event will be declared if met.The maximum value shown on T.S. Figure 3.4. 15-1 is 137.5 uCi/gm dose equivalent 1-131;therefore this value is included in the EAL threshold to address plant conditions below that shownin the T.S. figure. (ref. 1, 2).CCNPP Basis Reference(s):1. Technical Specification 3.4.15 Reactor Coolant System -RCS Specific Activity2. AOP-6A Abnormal Reactor Coolant Chemistry/Activity3. 1(2)C07-ALM F-21 RAD MON LVL HI4. NEI 99-01 SU4February 2016220EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: S -System MalfunctionSubcategory: 7 -Fuel Clad DegradationInitiating Condition: Fuel clad degradationEAL:SU7.2 Unusual EventLetdown Monitor (RY-202-1) high alarm (> 1E+06 cpm)Mode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericThis EAL is included because it is a precursor of more serious conditions and, as result, isconsidered to be a potential degradation of the level of safety of the plant.Escalation of this EAL to the Alert level is via the EALs in Category F.This threshold addresses radiation monitor readings that provide indication of a degradation of fuelclad integrity.Plant-SpecificThis EAL addresses indication of gross failed fuel that may be in excess of Technical Specification(ref. 1) coolant activity limits.The Letdown Radiation Monitor (1 (2)-RY-202-1)) gross radiation channel continuously monitors theactivity in a sample drawn from the RCS and actuates an alarm in the Control Room if apredetermined activity level is reached (ref. 3). The sensor is a gross-gamma plus specific isotope(1-135) monitor; the system is designed to detect activity release from the fuel to the reactor coolantwithin five minutes of the event (ref. 2, 3). The instrument range is 10 -1E+6 cpm. RY-202-1 doesnot read out in pCi/cc (ref. 4).CCNPP Basis Reference(s):1. Technical Specification 3.4.15 Reactor Coolant System -RCS Specific Activity2. AOP-6A Abnormal Reactor Coolant Chemistry/Activity3. 1I(2)C07-ALM F-21 RAD MON LVL HI4. UFSAR Section 9.1.35. NEI 99-01 SU4February 2016 221 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexE~xnlnn NuclerIArCategory:S -System MalfunctionSubcategory: 8 -RCS LeakageInitiating Condition: RCS leakageEAL:SU8.1 Unusual EventUnidentified or pressure boundary leakage > 10 gpm for > 15 min. (Note 4)ORIdentified leakage > 25 gpm for > 15 min. (Note 4)Note 4: The ED should not wait until the applicable time has elapsed, but should declare the event as soonas it is determined that the condition has exceeded, or will likely exceed, the applicable time.Mode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericThis EAL is included as a UE because it may be a precursor of more serious conditions and, asresult, is considered to be a potential degradation of the level of safety of the plant. The 10 gpmvalue for the unidentified or pressure boundary leakage was selected as it is observable withnormal Control Room indications. Lesser values must generally be determined through time-consuming surveillance tests (e.g., mass balances).Relief valve normal operation should be excluded from this EAL. However, a relief valve thatoperates and fails to close per design should be considered applicable to this EAL if the relief valvecannot be isolated.The EAL for identified leakage is set at a higher value due to the lesser significance of identifiedleakage in comparison to unidentified or pressure boundary leakage. In either case, escalation ofthis EAL to the Alert level is via EALs in Category F.Plant-SpecificSTP 0-27-1(2), RCS Leakage Evaluation, provides instructions for calculating primary system leakrate by manual or PC program methods (ref. 2). AOP-2A-I (2), Excessive Reactor CoolantLeakage, provides direction for determining ROS leakage for off normal events and for operationstroubleshooting (ref. 3).February 2016222EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCalvert Cliffs Technical Specifications do not treat Steam Generator tube leakage as RCS pressureboundary leakage. Since Steam Generator tube leakage is identified leakage, the threshold forUnususal Event is > 25 gpm under this initiating condition.CCNPP Basis Reference(s):1. Technical Specifications 3.4.13, Reactor Coolant System Operational Leakage2. AOP-2A Excessive Reactor Coolant Leakage3. STP 0-27-1 (2) RCS Leakage Evaluation4. Technical Specifications 1.1, Definitions5. NEI 99-01 SU5February 2016223EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategiory F -Fission Product Barrier DegqradationEAL Group: Hot Conditions (RCS temperature > 200°F); EALsin this category are applicable only in one or morehot operating modes.EALs in this category represent threats to the defense in depth design concept that precludes therelease of highly radioactive fission products to the environment. This concept relies on multiplephysical barriers any one of which, if maintained intact, precludes the release of significantamounts of radioactive fission products to the environment. The primary fission product barriersare:A. Reactor Fuel Clad (FC): The fuel clad barrier consists of fuel bundle tubes composed ofzirconium-based alloys that contain the fuel pellets.B. Reactor Coolant System (RCS): The RCS Barrier includes the RCS primary side and itsconnections up to and including the pressurizer safety and relief valves, and otherconnections up to and including the primary isolation valves.C. Containment (CNMT): The Containment Barrier includes the Containment building andconnections up to and including the outermost Containment isolation valves. This barrieralso includes the main steam, feedwater, and blowdown line extensions outside theContainment building up to and including the outermost secondary side isolation valve.The EALs in this category require evaluation of the loss and potential loss thresholds listed in thefission product barrier matrix of Table F-I (Attachment 2). "Loss" and "Potential Loss" signify therelative damage and threat of damage to the barrier. "Loss" means the barrier no longer assuresContainment of radioactive materials. "Potential Loss" means integrity of the barrier is threatenedand could be lost if conditions continue to degrade. The number of barriers that are lost orpotentially lost and the following criteria determine the appropriate emergency classification level:Unusual Event:Any loss or any potential loss of ContainmentAlert:Any loss or any potential loss of either Fuel Clad or RCSSite Area Emerqency:Loss or potential loss of any two barriersGeneral Emergqency:Loss of any two barriers and loss or potential loss of the third barrierFebruary 2016 224 EP-AA-I101 Addendum 3(Revision I)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearThe logic used for Category F EALs reflects the following considerations:*The Fuel Clad Barrier and the RCS Barrier are weighted more heavily than theContainment Barrier. UE EALs associated with RCS and Fuel Clad Barriers are addressedunder Category S.*At the Site Area Emergency level, there must be some ability to dynamically assess how farpresent conditions are from the threshold for a General Emergency. For example, if FuelClad and RCS Barrier "Loss" thresholds existed, that, in addition to off-site doseassessments, would require continual assessments of radioactive inventory andContainment integrity. Alternatively, if both Fuel Clad and RCS Barrier "Potential Loss"thresholds existed, the ED would have more assurance that there was no immediate needto escalate to a General Emergency.*The ability to escalate to higher emergency classification levels as an event deterioratesmust be maintained. For example, RCS leakage steadily increasing would represent anincreasing risk to public health and safety.*The Containment Barrier should not be declared lost or potentially lost based on exceedingTechnical Specification action statement criteria, unless there is an event in progressrequiring mitigation by the Containment barrier. When no event is in progress (Loss orPotential Loss of either Fuel Clad and/or RCS) the Containment Barrier status is addressedby Technical Specifications.February 2016225EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCliffs AnnexFxalnn Ne.lr~c~r................... m R ! Category: Fission Product Barrier DegradationSubcategory: N/AInitiating Condition: ANY loss or ANY potential loss of ContainmentEAL:FUI.1 Unusual EventANY loss or ANY potential loss of Containment (Table F-I)Mode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericNonePIa nt-SpecificFuel Clad, RCS and Containment comprise the fission product barriers. Table F-i (Attachment 2)lists the fission product barrier thresholds, bases and references.Fuel Clad and RCS barriers are weighted more heavily than the Containment barrier. Unlike theFuel Clad and RCS barriers, the loss of either of which results in an Alert (EAL FA .1), loss of theContainment barrier in and of itself does not result in the relocation of radioactive materials or thepotential for degradation of core cooling capability. However, loss or potential loss of theContainment barrier in combination with the loss or potential loss of either the Fuel Clad or RCSbarrier results in declaration of a Site Area Emergency under EAL FS1 .1.CCNPP Basis Reference(s):1. NEI 99-01 FU1February 2016226EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory: Fission Product Barrier DegradationSubcategory: N/AInitiating Condition: ANY loss or ANY potential loss of either Fuel Clad or RCSEAL:FAl.1 AlertANY loss or ANY potential loss of either Fuel Clad or RCS (Table F-I)Mode Applicability:I -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericNonePlant-SpecificFuel Clad, RCS and Containment comprise the fission product barriers. Table F-I (Attachment 2)lists the fission product barrier thresholds, bases and references.At the Alert classification level, Fuel Clad and RCS barriers are weighted more heavily than theContainment barrier. Unlike the Containment barrier, loss or potential loss of either the Fuel Clad orRCS barrier may result in the relocation of radioactive materials or degradation of core coolingcapability. Note that the loss or potential loss of Containment barrier in combination with loss orpotential loss of either Fuel Clad or RCS barrier results in declaration of a Site Area Emergencyunder EAL FSI.CCNPP Basis Reference(s):1. NEI 99-01 FA1February 2016227EP-AA-1011 Addendum 3(Revision I)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearCategory: Fission Product Barrier DegradationSubcategory: N/AInitiating Condition: Loss or potential loss of ANY two barriersEAL:FSI.1 Site Area EmergencyLoss or potential loss of ANY two barriers (Table F-i)Mode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericNonePlant-SpecificFuel Clad, RCS and Containment comprise the fission product barriers. Table F-I (Attachment 2)lists the fission product barrier thresholds, bases and references.At the Site Area Emergency classification level, each barrier is weighted equally. A Site AreaEmergency is therefore appropriate for any combination of the following conditions:* One barrier loss and a second barrier loss (i.e., loss -loss)* One barrier loss and a second barrier potential loss (i.e., loss -potential loss)* One barrier potential loss and a second barrier potential loss (i.e., potential loss -potentialloss)At the Site Area Emergency classification level, the ability to dynamically assess the proximity ofpresent conditions with respect to the threshold for a General Emergency is important. Forexample, the existence of Fuel Clad and RCS Barrier loss thresholds in addition to offsite doseassessments would require continual assessments of radioactive inventory and Containmentintegrity in anticipation of reaching a General Emergency classification. Alternatively, if both FuelClad and RCS potential loss thresholds existed, the Emergency Director would have greaterassurance that escalation to a General Emergency is less imminent.CCNPP Basis Reference(s):1. NEI 99-01 FSIFebruary 2016 228 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCategory:Su bcategory:Initiating Condition:Fission Product Barrier DegradationN/ALoss of ANY two barriers and loss or potential loss of the thirdbarrierEAL:FGI.1 General EmergencyLoss of ANY two barriersANDLoss or potential loss of the third barrier (Table F-I)Mode Applicability:1 -Power Operation, 2 -Startup, 3 -Hot Standby, 4 -Hot ShutdownBasis:GenericNonePlant-SpecificFuel Clad, RCS and Containment comprise the fission product barriers. Table F-I (Attachment 2)lists the fission product barrier thresholds, bases and references.At the General Emergency classification level each barrier is weighted equally. A GeneralEmergency is therefore appropriate for any combination of the following conditions:* Loss of Fuel Clad, RCS and Containment barriers* Loss of Fuel Clad and RCS barriers with potential loss of Containment barrier* Loss of RCS and Containment barriers with potential loss of Fuel Clad barrier* Loss of Fuel Clad and Containment barriers with potential loss of ROS barrierCCNPP Basis Reference(s):I. NE1 99-01 FG1February 2016229EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearATTACHMENT 2Fission Product Barrier Loss I Potential Loss Matrix and BasisIntroductionTable F-I lists the threshold conditions that define the Loss and Potential Loss of the three fissionproduct barriers (Fuel Clad, Reactor Coolant System, and Containment). The table is structured sothat each of the three barriers occupies adjacent columns. Each fission product barrier column isfurther divided into two columns; one for Loss thresholds and one for Potential Loss thresholds.The first column of the table (to the left of the Fuel Clad Loss column) lists the categories (types) offission product barrier thresholds. The fission product barrier categories are:A. Core Cooling / Heat RemovalB. InventoryC. Radiation / Coolant ActivityD. Isolation StatusE. JudgmentEach category occupies a row in Table F-I thus forming a matrix defined by the category rows andthe Loss/Potential Loss columns. The intersection of each category row with each Loss/PotentialLoss column forms a cell in which one or more fission product barrier thresholds appear. If NEI 99-01 does not define a threshold for a barrier Loss/Potential Loss, the word "None" is entered in thecell.Thresholds are assigned sequential numbers within each Loss and Potential Loss columnbeginning with number one. In this manner, a threshold can be identified by its category title andnumber. For example, the first Fuel Clad barrier Loss in Category A is "FC Loss A.I ," the thirdContainment barrier Potential Loss is "CNMT P-Loss B.3," etc.If a cell in Table F-I contains more than one numbered threshold, each of the numberedthresholds, if exceeded, signifies a Loss or Potential Loss of the barrier. It is not necessary toexceed all of the thresholds in a category before declaring a barrier Loss/Potential Loss.Subdivision of Table F-I by category facilitates association of plant conditions to the applicablefission product barrier Loss and Potential Loss thresholds. This structure promotes a systematicapproach to assessing the classification status of the fission product barriers.When equipped with knowledge of plant conditions related to the fission product barriers, the EAL-user first scans down the category column of Table F-l, locates the likely category and then readsFebruary 2016 230 EP-AA-1011 Addendum 3(Revision I)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclearacross the row of fission product barrier Loss and Potential Loss thresholds in that category todetermine if any threshold has been exceeded. If a threshold has not been exceeded in thatcategory row, the EAL-user proceeds to the next likely category and continues review of the row ofthresholds in the new categoryThe EAL-user must examine each of the three fission product barriers to determine if other barrierthresholds in the category are lost or potentially lost. For example, if Containment radiation issufficiently high (i.e., greater than 14,000 R/hr), a Loss of the Fuel Clad and RCS barriers and aPotential Loss of the Containment barrier exist. Barrier Losses and Potential Losses are thenapplied to the algorithm~s given in EALs FGI.1, FSI.1, FAI.1 and FU1.1 to determine theappropriate emergency classification.In the remainder of this Attachment, the Fuel Clad barrier threshold bases appear first, followed bythe RCS barrier and finally the Containment barrier threshold bases. In each barrier, the bases aregiven according category Loss followed by category Potential Loss beginning with Category A,then B... E.February 2016231EP-AA-1011 Addendum 3(Revision 1)

Calvert Cts AnnexExelon Gonfid*l/ProprietaryExelon N~earTable F-I Fission Product Barrier MatrixFuel Clad Barrier Reactor Coolant System Barrier Containment BarrierCategory Loss Potential Loss Loss Potential Loss Loss Potential Loss1. OTGG flow established1. GET readings > 7000F 2. RCS heat removal cannot be 1. GET readings cannot be restoredestablished < 1,200°F within 15 mai.""2. RGS heat removal cannot be ROS pressure>* PORVCore GTestablished setpoint None 2. GET readings>* 7000FCooling / 1. CTreadings>* 1,2OD°F AND EITHER: None OR ANDHeat RGS pressure > PORV RGS subcooling < 25°FRemoval setpoint Reactor vessel waler level cannotOR be restored > RVLMS 10 in. alarmORGsucoig25F3 Uncontrolled RGS co oldown and to within 15 win.RCS ubcolin < 5°Fleft of Max Operating PressureGurve (EOP Attachment 1, RGSPressure Temperature Limits)1.A Gontainment pressure risefollowed by a rapid unexplaineddrop in Gontainment pressure 3. Gontainment pressure - 50 psigand rising2.Containment pressure or sumplevel response not consistent 4. Gontainment hydrogen1. RGS leak rate>* available with LOGA conditions concentration 4%makeup capacity as indicated bya loss of RGS subcoolingBNone 3. RVLMS level a 10 in. alarm (<25OF)4 RCS leak rate > 50 gpm with 3.RUPTURED SIG (> 50 gpm) is 5. Gontainment pressure >4.25Ivnoyletdown isolated also FAULTED outside of psig AND cannot meet ANY ofGontainment the following conditions:2.RUPTURED SIG results in anEGGSISIA) atuaton 2 Gontainment Spray Pumps4.S(SA) cuainPrimary-to-secondary leakrate Operating*10 gpm

• 3 GA~s OperatingAND

• I Gontainment Spray PumpUnisolable prolonged steam and 2 GA~s Operatingrelease from affected S/G to theenvironment2. Gontainment radiation monitor(5317A1B) reading>*3,500 R/hrCRadiation 3. Post-accident sample dose rate Nonon3tainme) readiaing monR/or NoeNne6 Containment radiation monitor/ Coolant 40 mftem/hr (1 ft from sample) Noe(NoteS/) redn rNn oe(5317YA/B) reading > 14,000 R/hrAtiW 4. Goolant activity >300 p~i/ccDEO 1-1315.Failure of all valves in ANY oneot line to closeIoainNone None None None NoneStatus the environment exists afterGontainment isolation signalS 5. ANY condition in the opinion of 4. ANY condition in the opinion of 4.AYcniini6h pno f 5 N odto nteoiino h .ANY condition in the opinion of 7. ANY condition in the opinion of theEthe Emergency Director that the Emergency Director that the Emergcyndi rectorn th at Emergef .n cy co diretior that oindicafthes the Emergency Director that Emergency Director that indicatesinicte loso h ulca niae oeta oso hul idcthes lossenc irof the G arret Emrec feco tha ind0atb indicates loss of the Gontainment potential loss of the GontainmentJudgment barrieriniae oso h ulca cladin aebarrierPtnalosofheul idcts ssfthRCbrir potential oss f the CS barrier barrier barrierFebruary 2016232EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: Fuel CladCategory: A. Core Cooling/Heat RemovalDegradation Threat: LossThreshold:1. CET readings > 1 ,200°FBasis:GenericThe 1,1200°F reading corresponds to significant superheating of the coolant.Plant-SpecificCore Exit Thermocouples (CETs) are a component of Inadequate Core Cooling Instrumentationand provide an indirect indication of fuel clad temperature by measuring the temperature of thereactor coolant that leaves the core region. The threshold temperature is consistent withAttachment 3 of ERPIP-802, Core Damage Assessment Using Core Exit Thermocouples. Althoughclad rupture due to high temperature is not expected for CET readings less than the threshold,temperatures of this magnitude signal significant superheating of the reactor coolant and coreuncovery. Events that result in CET readings above the loss threshold are classified severeaccidents and lead to a Severe Accident Management Guideline "Badly Damaged (BD)" condition.The BD descriptor signifies possible core overheating to the point clad ballooning/collapse mayhave occurred and portions of the core may melt.CCNPP Basis Reference(s):1. UFSAR7.5.92. ERPIP-600 Severe Accident Management3. ERPIP-601 Severe Accident Management Initial Diagnosis4. ERPIP-802 Core Damage Assessment Using Core Exit Thermocouples5. EOP-5 Loss of Coolant Accident6. EOP-8 Functional Recovery Procedure7. CEN-152 Emergency Procedure GuidelinesFebruary 2016 233 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: Fuel CladCategory: A. Core Cooling/Heat RemovalDegradation Threat: Potential LossThreshold:1. CET readings > 700°FBasis:GenericCET readings > 700°F corresponds to loss of subcooling.Plant-SpecificCore Exit Thermocouples (CETs) are a component of the Inadequate Core CoolingInstrumentation and provide an indirect indication of fuel clad temperature by measuring thetemperature of the reactor coolant that leaves the core region. The RCS Pressure Safety Limit is2750 psia per CCNPP Technical Specifications. The saturation temperature for this pressure is682.2°F. Per Action Value Bases Document EOP-24.33, the uncertainty on CET Temperature is+/- 39.8°F. If one or more CETs indicate 722°F (682.2 + 39.8), subcooling has been lost for atleast some locations in the core. CET indications at or above 7220°F are a clear sign that core heatremoval capability is lost or greatly reduced and one fission product barrier, the fuel clad, isthreatened due to elevated fuel temperatures. 700°F qualifies as a condition representing apotential loss of the fuel clad barrier (ref. 6).CCNPP Basis Reference(s):1. UFSAR 7.5.92. ERPIP-800 Core Damage Assessment3. ERPIP-802 Core Damage Assessment Using Core Exit Thermocouples4. EOP-5 Loss of Coolant Accident5. EOP-8 Functional Recovery Procedure6. EOP-24.33 Actio~n Value Bases Document7. CEN-152 Emergency Procedure GuidelinesFebruary 2016 234 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCulvert Cliffs AnnexExelon Nuclear....................................Barrier:Category:Fuel CladA. Core Cooling/Heat RemovalDegRadhatio Tremoat: PanotbentialaLossheTReShold ue>:OV epon2. RCS heat removal cannot be establishedAND EITHER:RCS pressure> PORV setpointORRCS subcooling <250FBasis:GenericThis subcategory addresses other site specific thresholds that may be included to indicate loss orpotential loss of the Fuel Clad barrier.Plant-SpecificThe steam generators (S/Gs) provide the normal means of heat transfer from the RCS to the maincondenser and ultimate heat sink. EOP-5, Loss of Coolant Accident, requires maintenance of S/Gheat removal at all times during a LOCA, if at all possible. Once RCS pressure and temperatureare reduced, RCS heat removal can be provided by Shutdown Cooling (SDC). Once the SOC isplaced in service, the S/G heat sink capability is no longer necessary.S/Gs are available for RCS heat removal if the level in at least one S/G can be restored andmaintained above -170 in. and TCOLD is not increasing. Core and ROS heat removal is available ifCET readings are less than superheated and the temperature difference between hot legtemperature and cold leg temperature is less than 500F (10°F with forced circulation). If RCSpressure approaches the PORV setpoint (2,400 psia), heat input to the RCS is likely raisingpressure instead of reaching the ultimate heat sink. If RCS subcooling approaches 25°F, themargin to superheated conditions is being reduced. Following an uncomplicated reactor trip,subcooling margin should be in excess of 500F. Subcooling margin greater than 25°F ensures thefluid surrounding the core is sufficiently cooled and provides margin for reestablishing flow shouldFebruary 2016235EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclearsubcooling deteriorate when SI flow is secured. Voids may exist in some parts of the RCS (e.g.,Reactor Vessel head) but are permissible as long as core heat removal is maintained.The combination of these conditions indicates the ultimate heat sink function is under extremechallenge. This threshold addresses loss of functions required for hot shutdown with the reactor atpressure and temperature and thus a potential loss of the Fuel Clad barrier. This is also a potentialloss of the RCS barrier and therefore results in at least a Site Area Emergency.CCNPP Basis Reference(s):1. UFSAR Section 7.5.92. OP-7 Shutdown Operations3. ERPIP-601 Severe Accident Management Initial Diagnosis4. ERPIP-800 Core Damage Assessment5. ERPIP 802 Core Damage Assessment Using Core Exit Thermocouples6. EOP-5 Loss of Coolant Accident7. EOP-8 Functional Recovery Procedure8. EOP-23.02 Subcooling Margin (SCM): 25 Deg F Subcooled9. CEN-152 Emergency Procedure GuidelinesFebruary 2016236EP-AA-1011 Addendum 3(Revision 1I)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexBarrier: Fuel CladCategory: B. InventoryDegradation Threat: LossThreshold:Exelon NuclearNoneFebruary 2016237EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: Fuel CladCategory: B. InventoryDegradation Threat: Potential LossThreshold:3. RVLMS < 10 in. alarmBasis:GenericThere is no Loss threshold associated with this item.The site specific value for the Potential Loss threshold corresponds to the top of the active fuel.Plant-SpecificThe Reactor Vessel Level Monitoring System (RVLMS) is based on the CE Heated JunctionThermocouple (HJTC) system. The HJTC system measures reactor coolant liquid inventory withdiscrete HJTC sensors located at different levels within a separator tube ranging from the fuelalignment plate (i.e., near top of active fuel) to the top of the Reactor Vessel head. The basicprinciple of system operation is detection of a temperature difference between heated andunheated thermocouples.Reactor Vessel water level below the top of the core may lead to a Severe Accident ManagementGuideline "Badly Damaged (BD)" condition. The BD descriptor signifies possible core overheatingto the point of clad ballooning/collapse and melting. When Reactor Vessel/RCS water level dropsto 32.9 ft el., core uncovery is about to occur. The closest RVLMS indication is the 10 in. alarm.This signals inadequate coolant inventory, loss of subcooling and the occurrence of possible fuelclad damage.CCNPP Basis Reference(s):1. UFSAR7.5.92. ERPIP-800 Core Damage Assessment3. OP-7 Shutdown Operations4. ERPIP-600 Severe Accident Management5. ERPIP-601 Severe Accident Management Initial DiagnosisFebruary 2016 238 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:Category:Fuel CladC. Radiation / Coolant ActivityDegradation Threat: LossThreshold:2. Containment radiation monitor (5317A/B) reading > 3,500 R/hrBasis:GenericThe 3,500 R/hr Containment radiation monitor reading is a value which indicates the release ofreactor coolant, with elevated activity indicative of fuel damage, into the Containment.Reactor coolant concentrations of this magnitude are several times larger than the maximumconcentrations (including iodine spiking) allowed within technical specifications and are thereforeindicative of fuel damage.This value is higher than that specified for RCS barrier Loss threshold #3. Thus, this thresholdindicates a loss of both the Fuel Clad barrier and RCS barrier that appropriately escalates theemergency classification level to a Site Area Emergency.There is no Potential Loss threshold associated with this item.Plant-SpecificContainment radiation is indicated on 1 (2)-RI-5317 A&B.CCNPP Basis Reference(s):1. ERPIP-801 Core Damage Assessment Using Containment Radiation Dose RatesFebruary 2016239EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:Category:Fuel CladC. Radiation / Coolant ActivityDegradation Threat: LossThreshold:3. Post-accident sapedose rate > 40 mRem/hr (1ft from samleBasis:GenericThe post accident sample dose rate value corresponds to 300 #.Ci/gm 1-131 equivalent.Assessment by the EAL Task Force indicates that this amount of coolant activity is well above thatexpected for iodine spikes and corresponds to less than 5% fuel clad damage. This amount ofradioactivity indicates significant clad damage and thus the Fuel Clad Barrier is considered lost.There is no Potential Loss threshold associated with this item.Plant-SpecificA shielded 12.5 ml pressurized bomb sample would read 40 mRem/hr at one foot from the sample(168 mRem/hr unshielded) for 5% fuel clad damage. When reactor coolant activity reaches thislevel, significant clad heating has occurred and thus the Fuel Clad barrier is considered lost (ref. 1).CCNPP Basis Reference(s):1. BG&E Fuel Degradation EALs Calculation Worksheet, JSB Associates, February 18, 1993February 2016240EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:Fuel CladCategory:C. Radiation / Coolant ActivityDegrooadtactionThet: LosspccDQ -34. Coolant activity> 300 pCi/cc DEQ 1-131Basis:GenericThe site specific value corresponds to 300 pCi/cc 1-131 equivalent. Assessment by the EAL TaskForce indicates that this amount of coolant activity is well above that expected for iodine spikesand corresponds to less than 5% fuel clad damage. This amount of radioactivity indicatessignificant clad damage and thus the Fuel Clad Barrier is considered lost.There is no Potential Loss threshold associated with this item.Plant-SpecificNoneCCNPP Basis Reference(s):1. NEI 99-01 Revision 5, pg 35February 2016241EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexBarrier: Fuel CladCategory: C. Radiation I Coolant ActivityDegradation Threat: Potential LossThreshold:Exelon NuclearNoneFebruary 2016242EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier: Fuel CladCategory: D. Isolation StatusDegradation Threat: LossThreshold:NoneFebruary 2016243EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexS Barrier: Fuel CladCategory: D. Isolation StatusDegradation Threat: Potential LossThreshold:Exelon NuclearNoneFebruary 2016244EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:Fuel CladCategory:Degradation Threat:E. JudgmentLossThreshold:Basis:GenericThis threshold addresses any other factors that are to be used by the Emergency Director indetermining whether the Fuel Clad barrier is lost. In addition, the inability to monitor the barriershould also be incorporated in this threshold as a factor in Emergency Director judgment that thebarrier may be considered lost.Plant-SpecificThe Emergency Director judgment threshold addresses any other factors relevant to determining ifthe Fuel Clad barrier is lost. Such a determination should include imminent barrier degradation,barrier monitoring capability and dominant accident sequences.CCNPP Basis Reference(s):NoneFebruary 2016245EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:Fuel CladCategory:E. JudgmentDegradation Threat: Potential LossThreshold:4. ANY condition in the opinion of the Emergency Director that indicates potential loss ofthe Fuel Clad barrierBasis:GenericThis threshold addresses any other factors that are to be used by the Emergency Director indetermining whether the Fuel Clad barrier is I potentially lost. In addition, the inability to monitor thebarrier should also be incorporated in this threshold as a factor in Emergency Director judgmentthat the barrier may be considered potentially lost.Plant-SpecificThe Emergency Director judgment threshold addresses any other factors relevant to determining ifthe Fuel Clad barrier is potentially lost. Such a determination should include imminent barrierdegradation, barrier monitoring capability and dominant accident sequences.CCNPP Basis Reference(s):NoneFebruary 2016246EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/Proprietary(aln~r4 CllffQ AnnawIFv~lnn hi,v-Il~r5 VliiltV bA¥IVII IIISItSI'IVHIIBarrier:Category:Degradation Threat:Threshold:NoneReactor Coolant SystemA. Core Cooling/Heat RemovalLossFebruary 2016247EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:Category:Reactor Coolant SystemA. Core Cooling/Heat RemovalDegradation Threat: Potential LossThreshold:1. OTCC flow establishedBasis:GenericThis subcategory addresses other site specific thresholds that may be included to indicate loss orpotential loss of the RCS barrier.Plant-SpecificCCNPP is a CE plant with Once Through Core Cooling (OTCC) capability and has a procedurethat intentionally opens the RCS barrier to cool the core when normal means fail. This procedure isemployed when the heat removal function is extremely challenged. Establishment of OTCC flowrepresents a potential loss of the RCS barrier due to PORVs being intentionally maintained open toestablish adequate core heat removal capability.CCNPP Basis Reference(s):1. EOP-3 Loss of All FeedwaterFebruary 2016248EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:Reactor Coolant SystemCategory:A. Core Cooling/Heat RemovalDegradation Threat: Potential LossThreshold:2. RCS heat removal cannot be establishedAND EITHER:RCS pressure > PORV setpointORRCS subcooling < 250 FBasis:GenericThis subcategory addresses other site specific thresholds t'hat may be included to indicate loss orpotential loss of the RCS barrier.Plant-SpecificThe steam generators (S/Gs) provide the normal means of heat transfer from the RCS to the maincondenser and ultimate heat sink. By cooling down the SIGs, heat input to the RCS from thereactor core is reduced. EOP-5, Loss of Coolant Accident, requires maintenance of S/G heatremoval at all times during a LOCA, if at all possible. Once RCS pressure and temperature arereduced, RCS heat removal can be provided by the Shutdown Cooling (SDC). Once the SDC isplaced in service, the S/G heat sink capability is no longer necessary.S/Gs are available for RCS heat removal if the level in at least one S/G can be restored andmaintained above -170 in. and TCOLD is not increasing. Core and RCS heat removal is available ifCET readings are less than superheated and the temperature difference between hot legtemperature and cold leg temperature is less than 50°F (100F with forced circulation). If RCSpressure approaches the PORV setpoint (2400 psia), heat input to the RCS is likely raisingpressure instead of reaching the ultimate heat sink. If RCS subcooling approaches 25°F, themargin to superheated conditions is being reduced. Following an uncomplicated reactor trip,subcooling margin should be in excess of 50°F. Subcooling margin greater than 25°F ensures theFebruary 2016249EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclearfluid surrounding the core is sufficiently cooled and provides margin for reestablishing flow shouldsubcooling deteriorate when SI flow is secured. Voids may exist in some parts of the RCS (e.g.,Reactor Vessel head) but are permissible as long as core heat removal is maintained.The combination of these conditions indicates the ultimate heat sink function is under extremechallenge. This threshold addresses loss of functions required for hot shutdown with the reactor atpressure and temperature and thus a potential loss of the RCS barrier. This is also a potential lossof the Fuel Clad barrier and therefore results in at least a Site Area Emergency.CCNPP Basis Reference(s):1. UFSAR Section 7.5.92. OP-7 Shutdown Operations3. ERPIP-601 Severe Accident Management Initial Diagnosis4. ERPIP-800 Core Damage Assessment5. ERPIP 802 Core Damage Assessment Using Core Exit Thermocouples6. EOP-5 Loss of Coolant Accident7. EOP-8 Functional Recovery Procedure8. EOP-23.02 Subcoo1ing Margin (SCM): 25 Deg F Subcooled9. CEN-152 Emergency Procedure GuidelinesFebruary 2016250EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: Reactor Coolant SystemCategory: A. Core Cooling/Heat RemovalDegradation Threat: Potential LossThreshold:3. Uncontrolled RCS cooldown and to left of Max Operating Pressure Curve (EOPAttachment 1, RCS Pressure Temperature Limits)Basis:GenericThis subcategory addresses other site specific thresholds that may be included to indicate loss orpotential loss of the RCS barrier.Plant-Specific"Uncontrolled" means that the RCS cooldown was not the result of deliberate action performed inaccordance with plant procedures and exceeds allowable vessel cooldown limits. Among the EOPsafety functions to be maintained is RCS Pressure Control. Per EOP-4, Excess Steam DemandEvent, the potential exists for pressurized thermal shock from an excessive cooldown rate followedby a repressurization.The Max Operating Pressure Curve and RCS cooldown rate limits are established to prevent theeffects of pressurized thermal shock. The region to the left of the curve is labeled the "Non-Operating Area." Several curves are included in EOP Attachment I based on the combinations ofReactor Coolant Pumps (RCPs) in operation. The combination of the conditions of this potentialloss threshold indicates the RCS barrier is under significant challenge.CCNPP Basis Reference(s):1. EOP-4 Excessive Steam Demand Event2. EOP-Attachments, Attachment I RCS Pressure Temperature Limits3. EOP-Attachments, Attachment 14 RCS Cooldown Data Sheet4. EOP-8 Functional Recovery ProcedureFebruary 2016 251 EP-AA-1O11 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: Reactor Coolant SystemCategory: B. InventoryDegradation Threat: LossThreshold:1. RCS leak rate > available makeup capacity as indicated by a loss of RCS subcooling(< 25°F)Basis:GenericThis threshold addresses conditions where leakage from the RCS is greater than availableinventory control capacity such that a loss of subcooling has occurred. The loss of subcooling isthe fundamental indication that the inventory control systems are inadequate in maintaining RCSpressure and inventory against the mass loss through the leak.Plant-SpecificAOP-2A, Excessive Reactor Coolant Leakage, provides a list of conditions that may be observedwhen excessive RCS leakage occurs and provides appropriate actions to prevent and mitigate theconsequences of RCS leakage. Following an uncomplicated reactor trip, subcooling margin shouldbe in the range of 50°F to 75°F. Subcooling margin greater than or equal to 25°F ensures the fluidsurrounding the core is sufficiently cooled and provides margin for reestablishing flow shouldsubcooling deteriorate when SIS flow is secured. Voids may exist in some parts of the ROS (e.g.,Reactor Vessel head) but are permissible as long as core heat removal is maintained. The loss ofsubcooling is therefore the fundamental indication that the inventory control systems are incapableof counteracting the mass loss through the leak in the RCS.The loss of subcooling as a result of inability to establish RCS heat transfer to the ultimate heatsink is indicative of potential losses of the Fuel Clad and RCS barriers.CCNPP Basis Reference(s):1. EOP-8 Subcooling Margin (SCM): 25 Deg F Subcooled2. AOP-2A Excessive Reactor Coolant Leakage3. EOP-5 Loss of Coolant Accident4. EOP-6 Steam Generator Tube RuptureFebruary 2016 252 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCliffsq lFvAInn Nirnlcurk vlmnnv m Barrier:Reactor Coolant SystemCategory:B. InventoryDegradation Threat: LossThreshold:2. RUPTURED SIG results in an ECCS (SIAS) actuationBasis:GenericThis threshold addresses the full spectrum of Steam Generator (SG) tube rupture events inconjunction with Containment barrier loss thresholds. It addresses ruptured SG(s) for which theleakage is large enough to cause actuation of ECCS (SIAS). This is consistent to the RCS leakrate barrier potential loss threshold.By itself, this threshold will result in the declaration of an Alert. However, if the SG is also faulted(i.e., two barriers failed), the declaration escalates to a Site Area Emergency per Containmentbarrier loss thresholds.There is no potential loss threshold associated with this item.Plant-SpecificDefinitions:RupturedIn a steam generator, existence of primary-to-secondary leakage of a magnitude sufficient torequire or cause a reactor trip and safety injection.CCNPP Basis Reference(s):1. EOP-5 Loss of Coolant Accident EOP-5 Loss of Coolant Accident2. EOP-6 Steam Generator Tube Rupture3. 1C08-ALM ESFAS 11, G-054. Technical Specifications Table 3.3.4-1February 2016253EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: Reactor Coolant SystemCategory: B. InventoryDegradation Threat: Potential LossThreshold:4. RCS leak rate > 50 gpm with letdown isolatedBasis:GenericThis threshold is based on the apparent inability to maintain normal liquid inventory within theReactor Coolant System (RCS) by normal operation of the Chemical and Volume Control Systemwhich is considered to be the flow rate equivalent to one charging pump discharging to thecharging header. Isolating letdown is a standard abnormal operating procedure action and mayprevent unnecessary classifications when a non-RCS leakage path such as a CVCS leak exists.The intent of this condition is met if attempts to isolate Letdown are NOT successful. Additionalcharging pumps being required is indicative of a substantial RCS leak.Plant-SpecificThe CVCS includes three positive displacement horizontal pumps with a capacity of 44 gpm each.The pressurizer level control program regulates letdown purification subsystem flow by adjustingthe letdown flow control valve so that the reactor coolant pump (RCP) controlled leak-off plus theletdown flow matches the input from the operating charging pump. Equilibrium pressurizer levelconditions may be disturbed due to RCS temperature changes, power changes, or RCS inventoryloss due to leakage. A decrease in pressurizer water level below the programmed level results in acontrol signal to start one or both standby charging pumps to restore water level. The need for asecond or third charging pump to makeup leakage in excess of letdown flow would be indicative ofsubstantial RCS leakage. The single charging pump capacity is rounded up to 50 gpm for thisthreshold and clearly signals that operation of more than one charging pump is needed.CCNPP Basis Reference(s):1. UFSAR Section 9.1.3February 2016 254 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: Reactor Coolant SystemCategory: C. Radiation / Coolant ActivityDegradation Threat: LossThreshold:3. Containment radiation monitor (5317A/B) reading > 6 R/hr (Note 8)Note 8: High temperature in Containment may induce a current error in the Mineral Insulated (Ml) cable runningthrough Containment to the meter. The CHRRM 1 (2)-Rl-531 7 A&B may not detect this value (6 R/hr) underthese conditions. When Containment temperature reaches 300°F, the meter will indicate approximately 40R/hr for a few minutes then drop to approximately 10 R/hr after three hours. This information is to provideguidance on determining the validity of the readings under the specified high temperature conditions.Basis:GenericThe site specific reading is a value which indicates the release of reactor coolant to theContainment.This reading is less than that specified for Fuel Clad barrier threshold 2. Thus, this threshold wouldbe indicative of a RCS leak only. If the radiation monitor reading increased to that specified by FuelClad barrier threshold, fuel damage would also be indicated.There is no Potential Loss threshold associated with this item.Plant-SpecificThe specified reading is based assuming the instantaneous release and dispersal of the reactorcoolant noble gas and iodine inventory associated with normal operating concentrations (i.e.,within Technical Specifications) into the Containment atmosphere. Because of the very high fuelclad integrity, only small amounts of noble gases would be dissolved in the reactor coolant. Thereading is less than that specified for Fuel Clad barrier Loss #2 because no damage to the fuelclad is assumed. Only leakage from the RCS is assumed for this barrier loss threshold.It is important to recognize that the radiation monitor may be sensitive to shine from the ReactorVessel or RCS piping. Containment radiation is indicated on 1 (2)-RI-531 7 A&B. TypicalContainment radiation readings at full power are 1 to 1 .2 R/hr. The Containment radiation monitorsalarm at 6 R/hr and so is operationally significant.Additionally, high temperatures in Containment may induce a current error in the Mineral Insulated(MI) cable running through Containment to the meter. The CHRRM may not detect this value (6February 2016 255 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearR/hr) under these conditions. CCNPP replaced the original cable with an improved Ml cable underESi199602293 to reduce the induced error to a minimum. When Containment temperature reaches300 degrees F, the meter will indicate approximately 40 R/hr for a few minutes then drop toapproximately 10 R/hr after three hours. This information is to provide guidance on determining thevalidity of the readings under the specified high temperature conditions. This information has beenadded as a note.CCNPP Basis Reference(s):1. ERPIP-801 Core Damage Assessment Using Containment Radiation Dose RatesFebruary 2016256EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexBarrier: Reactor Coolant SystemCategory: C. Radiation I Coolant ActivityDegradation Threat: Potential LossThreshold:Exelon NuclearNoneFebruary 2016257EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvedt Cliffs AnnexExelon NuclearBarrier: Reactor Coolant SystemCategory: D. Isolation StatusDegradation Threat: LossThreshold:NoneFebruary 2016258EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexBarrier: Reactor Coolant SystemCategory: D. Isolation StatusDegradation Threat: Potential LossThreshold:Exelon NuclearNoneFebruary 2016259EP-AA-1O11 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryAnnmrIPvnlnn Mnura-a~rBarrier:Reactor Coolant SystemCategory:E. JudgmentDegradation Threat: LossThreshold:Basis:GenericThis threshold addresses any other factors that are to be used by the Emergency Director indetermining whether the RCS barrier is lost. In addition, the inability to monitor the barrier shouldalso be incorporated in this threshold as a factor in Emergency Director judgment that the barriermay be considered lost.Plant-SpecificThe Emergency Director judgment threshold addresses any other factors relevant to determining ifthe RCS barrier is lost. Such a determination should include imminent barrier degradation, barriermonitoring capability and dominant accident sequences.CCNPP Basis Reference(s):NoneFebruary 2016260EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nurlea~r....... m ...............Barrier:Category:Reactor Coolant SystemE. JudgmentDegradation Threat: Potential LossThreshold:5. ANY condition in the opinion of the Emergency Director that indicates potential loss ofthe RCS barrierBasis:GenericThis threshold addresses any other factors that are to be used by the Emergency Director indetermining whether the RCS barrier is potentially lost. In addition, the inability to monitor thebarrier should also be incorporated in this threshold as a factor in Emergency Director judgmentthat the barrier may be considered potentially lost.Plant-SpecificThe Emergency Director judgment threshold addresses any other factors relevant to determining ifthe RCS barrier is potentially lost. Such a determination should include imminent barrierdegradation, barrier monitoring capability and dominant accident sequences.CCNPP Basis Reference(s):NoneFebruary 2016261EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexBarrier: ContainmentCategory: A. Core Cooling I Heat RemovalDegradation Threat: LossThreshold:Exelon NuclearNoneFebruary 2016262EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: ContainmentCategory: A. Core Cooling / Heat RemovalDegradation Threat: Potential LossThreshold:1. cET rednscannot be restored < 1 ,200°F within 15 min.Basis:GenericThere is no Loss threshold associated with this item.The conditions in this threshold represents an imminent core melt sequence which, if not corrected,could lead to vessel failure and an increased potential for Containment failure. In conjunction withthe Core Cooling and RCS Leakage criteria in the Fuel Clad and RCS barrier columns, thisthreshold would result in the declaration of a General Emergency -- loss of two barriers and thepotential loss of a third. If the function restoration procedures are ineffective, there is no "success"path.The function restoration procedures are those emergency operating procedures that address therecovery of the core cooling critical safety functions. The procedure is considered effective if thetemperature is decreasing or if the vessel water level is increasing.Whether or not the procedures will be effective should be apparent within 15 minutes. TheEmergency Director should make the declaration as soon as it is determined that the procedureshave been, or will be ineffective.Plant-SpecificThis threshold indicates significant core exit superheating and core uncovery. If Core ExitThermocouple (CET) readings are greater than 1 200°F, Fuel Clad barrier is lost. CETs are acomponent of the Inadequate Core Cooling Instrumentation system and provide an indirectindication of fuel clad temperature by measuring the temperature of the reactor coolant that leavesthe core region. The threshold temperature is consistent with Attachment 3 of ERPIP-802, CoreDamage Assessment Using Core Exit Thermocouples. Although clad rupture due to hightemperature is not expected for CET readings less than the threshold, temperatures of thismagnitude signal significant superheating of the reactor coolant and core uncovery. Events thatresult in CET readings above the loss threshold are classified severe accidents and lead to aSevere Accident Management Guideline "Badly Damaged (BD)" condition. The BD descriptorFebruary 2016 263 EP-AA-1 011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExnlnn NucleAar...................... B ...............signifies possible core overheating to the point that clad ballooning/collapse may occur andportions of the core may have melted.It must also be assumed the loss of RCS inventory is a result of a loss of the RCS barrier. Theseconditions, if not mitigated, can lead to core melt which in turn may result in a loss of Containment.Severe accident analyses (e. g., NUREG-1150) have concluded that function restorationprocedures can arrest core degradation within the Reactor Vessel in a significant fraction of thecore damage scenarios, and the likelihood of Containment failure is very small in these events.Given this, it is appropriate to provide a reasonable period to allow function restoration proceduresto arrest the core melt sequence. The phrase "cannot be restored <" infers CET readings haveexceeded the threshold temperature and procedural guidance used to restore RCS inventory hasbeen attempted but is thus far unsuccessful. Whether or not guidance is effective should beapparent within fifteen minutes. The ED should make the declaration as soon as it is determinedthe guidance has not been or will not be effective in restoring temperature below the threshold.CCNPP Basis Reference(s):ERPI P-600 Severe Accident ManagementERPIP-601 Severe Accident Management Initial DiagnosisERPIP-802 Core Damage Assessment Using Core Exit Thermocouples1.2.03February 2016264EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexI-xelnn NIclIA~r...................... m m Barrier: ContainmentDegradation Threat: Potential LossCategory:Threshold:A. Core Cooling / Heat Removal2. CET readings > 700°FANDReactor vessel water level cannot be restored > RVLMS 10 in. alarm within 15 mmn.Basis:GenericThere is no Loss threshold associated with this item.The conditions in this threshold represents an imminent core melt sequence which, if not corrected,could lead to vessel failure and an increased potential for Containment failure. In conjunction withthe Core Cooling and RCS Leakage criteria in the Fuel Clad and RCS barrier columns, thisthreshold would result in the declaration of a General Emergency -- loss of two barriers and thepotential loss of a third. If the function restoration procedures are ineffective, there is no "success"path.The function restoration procedures are those emergency operating procedures that address therecovery of the core cooling critical safety functions. The procedure is considered effective if thetemperature is decreasing or if the vessel water level is increasing.Whether or not the procedures will be effective should be apparent within 15 minutes. TheEmergency Director should make the declaration as soon as it is determined that the procedureshave been, or will be ineffective.Plant-SpecificThis threshold indicates loss of inventory control resulting in significant core exit superheating. TheReactor Vessel Level Monitoring System (RVLMS) can provide indication of potential coreuncovery when level decreases to 10 in. alarm. RVLMS is based on the CE Heated JunctionThermocouple (HJTC) system. The HJTC system measures reactor coolant liquid inventory withdiscrete HJTC sensors located at different levels within a separator tube ranging from the fuelalignment plate (i.e., near top of active fuel) to the Reactor Vessel head. The basic principle ofsystem operation is detection of a temperature difference between heated and unheatedthermocouples. Reactor Vessel water level below the top of the core may lead to a SevereFebruary 2016265EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearAccident Management Guideline "Badly Damaged (BD)" condition. The BD descriptor signifiespossible core overheating to the point that clad ballooning/collapse may occur and portions of thecore may have melted. Reactor Vessel water level at the 10 in. alarm signals inadequate coolantinventory, loss of subcooling and the occurrence of possible fuel clad damage.Core Exit Thermocouples (CETs) are a component of the Inadequate Core CoolingInstrumentation and provide an indirect indication of fuel clad temperature by measuring thetemperature of the reactor coolant that leaves the core region. The RCS Pressure Safety Limit is2750 psia per CCNPP Technical Specifications. The saturation temperature for this pressure is682.2°F. Per Action Value Bases Document EOP-24.33, the uncertainty on CET Temperature is+/- 39.8°F. If one or more CETs indicate 722°F (682.2 + 39.8), subcooling has been lost for atleast some locations in the core. CET indications at or above 722°F are a clear sign that core heatremoval capability is lost or greatly reduced and one fission product barrier, the fuel clad, isthreatened due to elevated fuel temperatures. 700°F qualifies as a condition representing apotential loss of the fuel clad barrier (ref. 4).It must be assumed the loss of RCS inventory is a result of a loss of the ROS barrier. Theseconditions, if not mitigated, likely lead to core melt which in turn may result in a loss ofContainment. Severe accident analyses (e. g., NUREG-1 150) have concluded that functionrestoration procedures can arrest core degradation within the Reactor Vessel in a significantfraction of the core damage scenarios, and that the likelihood of Containment failure is very smallin these events. Given this, it is appropriate to provide a reasonable period to allow functionrestoration procedures to arrest the core melt sequence. The phrase "cannot be restored >" inferscore uncovery has begun and procedural guidance used to restore RCS inventory has beenattempted but is thus far unsuccessful. Whether or not guidance is effective should be apparentwithin fifteen minutes. The ED should make the declaration as soon as it is determined that theguidance has not been or will not be effective in restoring vessel water level above the threshold.CCNPP Basis Reference(s):1. ERPIP-600 Severe Accident Management2. ERPIP-802 Core Damage Assessment Using Core Exit Thermocouples3. CEN-152 Emergency Procedure Guidelines4. EOP-24.33 Action Value Bases DocumentFebruary 2016 266 EP-AA-1 011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:Category:Degradation Threat:ContainmentB. InventoryLossThreshold:Basis:GenericRapid unexplained loss of pressure (i.e., not attributable to Containment spray or condensationeffects) following an initial pressure increase from a primary or secondary high energy line breakindicates a loss of Containment integrity. Containment pressure should increase as a result ofmass and energy release into Containment from a LOCA. Thus, pressure not increasing indicatesContainment bypass and a loss of Containment integrity.This indicator relies on operator recognition of an unexpected response for the condition andtherefore does not have a specific value associated with it. The unexpected response is importantbecause it is the indicator for a Containment bypass condition.Plant-SpecificUFSAR Section 14.20 describes Containment pressure response for a bounding LOCA.CCNPP Basis Reference(s):1. UFSAR Section 14.20February 2016267EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:ContainmentB. InventoryCategory:Degradation Threat: LossThreshold:2. Containment pressure or sump level response not consistent with LOCA conditionsBasis:GenericContainment sump levels should increase as a result of mass and energy release intoContainment from a LOCA. Thus, sump level not increasing indicates Containment bypass and aloss of Containment integrity.This indicator relies on operator recognition of an unexpected response for the condition andtherefore does not have a specific value associated with it. The unexpected response is importantbecause it is the indicator for a Containment bypass condition.Plant-SpecificThe Containment pressure and temperature response and Containment sump water temperatureresponse versus time are given in UFSAR Figures 6.2.1-1 through 6.2.1-6b for the most severeLOCAs. During the LOCA injection mode of ECCS operation, Containment sump and RWST levelsare monitored to ensure switch-over from injection to cold leg recirculation is initiated automaticallyand completed via timely operator action.CCNPP Basis Reference(s):1. UFSAR Figures 6.2.1-1 through 6.2.1-6bFebruary 2016268EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon Nuclear...................... m ...............Barrier:ContainmentB. InventoryCategory:Degradation Threat: LossThreshold:3. RUPTURED S/G is also FAULTED outside of ContainmentBasis:GenericThe loss threshold recognizes that SG tube leakage can represent a bypass of the Containmentbarrier as well as a loss of the RCS barrier.Users should realize that this threshold and Containment loss B.4 could be considered redundant.This was recognized during the development process. The inclusion of a threshold that usesEmergency Procedure commonly used terms like "ruptured and faulted" adds to the ease of theclassification process and has been included based on this human factor concern.This threshold results in a UE for smaller breaks that; (1) do not exceed the normal chargingcapacity threshold in RCS leak rate barrier Potential Loss threshold, or (2) do not result in ECCSactuation in RCS SG tube rupture barrier Loss threshold. For larger breaks, RCS barrier thresholdcriteria would result in an Alert. For SG tube ruptures which may involve multiple steam generatorsor unisolable secondary line breaks, this threshold would exist in conjunction with RCS barrierthresholds and would result in a Site Area Emergency. Escalation to General Emergency would bebased on "Potential Loss" of the Fuel Clad Barrier.This threshold addresses the condition in which a ruptured steam generator is also faulted. Thiscondition represents a bypass of the RCS and Containment barriers and is a subset of theContainment loss B.4. In conjunction with RCS leak rate barrier loss threshold, this would alwaysresult in the declaration of a Site Area Emergency.Plant-SpecificA faulted S/G means the existence of secondary side leakage that results in an uncontrolleddecrease in steam generator pressure or the steam generator being completely depressurized. Aruptured S/G means the existence of primary-to-secondary leakage of a magnitude sufficient torequire or cause a reactor trip and safety injection.February 2016269EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryC~I~u~r* (~IifF~ AnnoyI'volrn Mm uIl~rVlIIIV nIIIIVA I...A11i;lVII Definitions:FaultedIn a steam generator, the existence of secondary side leakage that results in an uncontrolleddrop in steam generator pressure or the steam generator being completely depressurized.RupturedIn a steam generator, existence of primary-to-secondary leakage of a magnitude sufficient torequire or cause a reactor trip and safety injection.CCNPP Basis Reference(s):1. EOP-6 Steam Generator Tube Rupture2. EOP-8 Functional Recovery ProcedureFebruary 2016270EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryAnnrnrI=Y~Ilnn hiJa-Il~rk VllalV

• Barrier:ContainmentB. InventoryCategory:Degradation Threat: LossThreshold:4. Primary-to-secondary leakrate > 10 gpmANDUnisolable or prolonged steam release from affected SIG to the environmentBasis:GenericThe loss threshold recognizes that SG tube leakage can represent a bypass of the Containmentbarrier as well as a loss of the RCS barrier.Users should realize that the this loss threshold and Containment loss B.3 could be consideredredundant. This was recognized during the development process. The inclusion of an thresholdthat uses Emergency Procedure commonly used terms like "ruptured and faulted" adds to the easeof the classification process and has been included based on this human factor concern.This threshold results in a UE for smaller breaks that; (1) do not exceed the normal chargingcapacity threshold in RCS leak rate barrier Potential Loss threshold, or (2) do not result in ECCSactuation in RCS SG tube rupture barrier Loss threshold. For larger breaks, RCS barrier thresholdcriteria would result in an Alert. For SG tube ruptures which may involve multiple steam generatorsor unisolable secondary line breaks, this threshold would exist in conjunction with RCS barrierthresholds and would result in a Site Area Emergency. Escalation to General Emergency would bebased on "Potential Loss" of the Fuel Clad Barrier.This threshold addresses SG tube leaks that exceed 10 gpm in conjunction with an unisolablerelease path to the environment from the affected steam generator. The threshold for establishingthe unisolable secondary side release is intended to be a prolonged release of radioactivity fromthe ruptured steam generator directly to the environment. This could be expected to occur whenthe main condenser is unavailable to accept the contaminated steam (i.e., SG tube rupture withconcurrent loss of off-site power and the ruptured steam generator is required for plant cooldownor a stuck open relief valve). If the main condenser is available, there may be releases via airejectors, gland seal exhausters, and other similar controlled, and often monitored, pathways.These pathways do not meet the intent of an unisolable release path to the environment. Theseminor releases are assessed using EALs in Category R.February 2016271EP-AA-101 1 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearPlant-SpecificCool downs conducted to allow controlled isolation of the affected SIG per emergency proceduresare not considered prolonged releases. The criterion for prolonged release is met if the objectiveof EOP-6 or EOP-8 to isolate the affected SIG cannot be met.Definitions:UnisolableA breach or leak that cannot be promptly isolated.CCNPP Basis Reference(s):1. EOP-6 Steam Generator Tube Rupture2. EOP-8 Functional Recovery ProcedureFebruary 2016272EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:Category:ContainmentB. InventoryThresoldimn: rssr 0pigadrsn3. Containment pressure 50 psig and risingBasis:GenericThe site specific pressure is based on the Containment design pressure.Plant-SpecificThis threshold is the Containment design pressure and is in excess of that expected from thedesign basis loss of coolant accident (LOCA). Proper actuation and operation of the Containmentspray system when required should maintain Containment pressure well below the designpressure. The pressure-time responses for the spectrum of LOCAs considered in the plant designbasis are described in Section 14 of the UFSAR. The threshold is therefore indicative of a loss ofboth RCS and Fuel Clad barriers in that it should not be reached without severe core degradation(metal-water reaction) or failure to scram in combination with RCS breach. This condition would beexpected to require the declaration of a General Emergency.CCNPP Basis Reference(s):1. UFSARI1.2.52. UFSAR5.1.13. UFSAR 14.20February 2016273EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: ContainmentCategory: B. InventoryDegradation Threat: Potential LossThreshold:4. Containment hydrogen concentration >4%Basis:GenericExistence of an explosive mixture means a hydrogen and oxygen concentration of at least thelower deflagration limit curve exists. The indications of potential loss under this EAL corresponds tosome of those leading to Containment potential loss threshold A.1.Plant-SpecificAfter a LOCA, the Containment atmosphere is a homogeneous mixture of steam, air, solid andgaseous fission products, hydrogen, and water droplets containing boron and sodium hydroxide.During and following a LOCA, the hydrogen concentration in the Containment results fromradiolytic decomposition of water, metal-water reaction, and aluminum/zinc reaction with the spraysolution. If hydrogen concentration reaches or exceeds the lower flammability limit (4%) in anoxygen rich environment, a potentially explosive mixture exists. If the combustible mixture ignitesinside Containment, loss of the Containment barrier could occur. To generate such levels ofcombustible gas, loss of the Fuel Clad and RCS barriers must also have occurred. Since thisthreshold is also indicative of loss of both Fuel Clad and RCS barriers with the potential loss of theContainment barrier, it therefore will likely warrant declaration of a General Emergency.CCNPP Basis Reference(s):1. UFSAR7.5.82. Technical Specifications Table 3.3.10-13. OI-41A Hydrogen Recombiners4. 1C10-ALM ESFAS 14 Alarm Manual, J-095. ERPIP-803 Core Damage Assessment Using Hydrogen6. EOP-8 Functional Recovery ProcedureFebruary 2016 274 EP-AA-1011 Addendum 3(Revision 1 )

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: ContainmentCategory: B. InventoryDegradation Threat: Potential LossThreshold:5. Containment pressure > 4.25 psig AND cannot meet ANY of the following conditions:* 2 Containment Spray Pumps Operating* 3 CACs Operating* 1 Containment Spray Pump and 2 CACs OperatingBasis:GenericThis threshold represents a potential loss of Containment in that the Containment heatremoval/depressurization system (e.g., Containment sprays, CACs, etc., but not includingContainment venting strategies) are either lost or performing in a degraded manner, as indicatedby Containment pressure greater than the setpoint at which the equipment was supposed to haveactuated.Plant-SpecificTwo Containment Spray Pumps, three Containment air cooling units or the combination of oneContainment spray pump and two Containment air cooling units is defined to be one full train ofdepressurization equipment. This equipment provides 100% of the required cooling capacity duringpost-accident conditions. Each Containment spray system consists of a spray pump, spray header,nozzles, valves, piping, instruments, and controls to ensure an operable flow path capable oftaking suction from the RWST upon an actuation signal. Each Containment aircooling unit consistsof cooling coils, accident backdraft damper, accident fan, service water outlet valves, and controlsnecessary to ensure an operable service water flow path. The Containment pressure setpoint (4.25psig) is the pressure at which the equipment should actuate and begin performing its function.CCNPP Basis Reference(s):1. 1 C08-ALM ESFAS 11 Alarm Manual, G-07, ACTUATION SYSTEM CSAS TRIP2. Technical Specifications Table 3.3.4-13. Technical Specifications 3.6.64. EOP-8 Functional Recovery, Appendix 5, CE-3February 2016 275 EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexBarrier: ContainmentCategory: C. Radiation I Coolant ActivityDegradation Threat: LossThreshold:Exelon NuclearNoneFebruary 2016276EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs Annex Exelon NuclearBarrier: ContainmentCategory: C. Radiation / Coolant ActivityDegradation Threat: Potential LossThreshold:6. Containment radiation monitor (5317A/B) reading > 14,000 R/hrBasis:GenericThere is no Loss threshold associated with this item.The site specific reading is a value which indicates significant fuel damage well in excess of thethresholds associated with both loss of Fuel Clad and loss of RCS barriers. A major release ofradioactivity requiring off-site protective actions from core damage is not possible unless a majorfailure of fuel clad allows radioactive material to be released from the core into the reactor coolant.Regardless of whether Containment is challenged, this amount of activity in Containment, ifreleased, could have such severe consequences that it is prudent to treat this as a potential loss ofContainment, such that a General Emergency declaration is warranted.Plant-SpecificThe Containment radiation monitor reading is a value that indicates significant fuel damage well inexcess of that required for loss of the RCS barrier and the Fuel Clad barrier. NUREG-1228"Source Estimations During Incident Response to Severe Nuclear Power Plant Accidents" statesthat such readings do not exist when the amount of clad damage is less than 20%. A major releaseof radioactivity requiring offsite protective actions from core damage is not possible unless a majorfailure into the reactor coolant has occurred. Regardless of whether the Containment barrier itselfis challenged, this amount of activity in Containment could have severe consequences if released.It is, therefore, prudent to treat this as a potential loss of the Containment barrier. The reading ishigher than that specified for Fuel Clad barrier Loss #3 and RCS barrier Loss #3. Containmentradiation readings at or above the Containment barrier potential loss threshold, therefore, signify aloss of two fission product barriers and potential loss of a third, indicating the need to upgrade theemergency classification to a General Emergency.Containment radiation is indicated on 1(2)-RI-5317 A&B. Typical Containment radiation readings atfull power are 1 to 1.2 R/hr. The Containment radiation monitors alarm at 6 R/hr.February 2016 277 EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearCCNPP Basis Reference(s):1. ERPIP-801 Core Damage Assessment Using Containment Radiation Dose RatesFebruary 2016278EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclealrBarrier:ContainmentCategory:D. Isolation StatusDegradation Threat: LossThreshold:5. Failure of all valves in ANY one line to closeANDDirect downstream pathway to the environment exists after Containment isolationsignalBasis:GenericThis threshold addresses incomplete Containment isolation that allows direct release to theenvironment.The use of the modifier "direct" in defining the release path discriminates against release pathsthrough interfacing liquid systems. The existence of an in-line charcoal filter does not make arelease path indirect since the filter is not effective at removing fission product noble gases. Typicalfilters have an efficiency of 95-99% removal of iodine. Given the magnitude of the core inventory ofiodine, significant releases could still occur. In addition, since the fission product release would bedriven by boiling in the reactor vessel, the high humidity in the release stream can be expected torender the filters ineffective in a short period.There is no Potential Loss threshold associated with this item.Plant-SpecificNoneCCNPP Basis Reference(s):1. EOP-8 Functional Recovery ProcedureFebruary 2016279EP-AA-1011 Adden'dum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier: ContainmentCategory: D. Isolation StatusDegradation Threat: Potential LossThreshold:NoneFebruary 2016280EP-AA-1 011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:ContainmentE. JudgmentCategory:Degradation Threat: LossThreshold:6. ANY condition in the opinion of the Emergency Director that indicates loss of theContainment barrierBasis:GenericThis threshold addresses any other factors that are to be used by the Emergency Director indetermining whether the Containment barrier is lost. In addition, the inability to monitor the barriershould also be incorporated in this threshold as a factor in Emergency Director judgment that thebarrier may be considered lost.The Containment barrier should not be declared lost or potentially lost based on exceedingTechnical Specification action statement criteria, unless there is an event in progress requiringmitigation by the Containment barrier. When no event is in progress (Loss or Potential Loss ofeither Fuel Clad and/or RCS) the Containment barrier status is addressed by TechnicalSpecifications.Plant-SpecificThe Emergency Director judgment threshold addresses any other factors relevant to determining ifthe Containment barrier is lost. Such a determination should include imminent barrier degradation,barrier monitoring capability and dominant accident sequences.CCNPP Basis Reference(s):NoneFebruary 2016281EP-AA-1011 Addendum 3(Revision 1)

Exelon Confidential/ProprietaryCalvert Cliffs AnnexExelon NuclearBarrier:ContainmentE. JudgmentCategory:Degradation Threat: Potential LossThreshold:7. ANY condition in the opinion of the Emergency Director that indicates potential loss ofthe Containment barrierBasis:GenericThis threshold addresses any other factors that are to be used by the Emergency Director indetermining whether the Containment barrier is potentially lost. In addition, the inability to monitorthe barrier should also be incorporated in this threshold as a factor in Emergency Directorjudgment that the barrier may be considered potentially lost.The Containment barrier should not be declared lost or potentially lost based on exceedingTechnical Specification action statement criteria, unless there is an event in progress requiringmitigation by the Containment barrier. When no event is in progress (Loss or Potential Loss ofeither Fuel Clad and/or RCS) the Containment barrier status is addressed by TechnicalSpecifications.Plant-SpecificThe Emergency Director judgment threshold addresses any other factors relevant to determining ifthe Containment barrier is potentially lost. Such a determination should include imminent barrierdegradation, barrier monitoring capability and dominant accident sequences.CCNPP Basis Reference(s):NoneFebruary 2016282EP-AA-1011 Addendum 3(Revision 1)