RS-13-099, Response to Request for Additional Information Related to License Amendment Request to Revise Technical Specifications Section 3.5.3, ECCS - Shutdown
| ML13122A046 | |
| Person / Time | |
|---|---|
| Site: | Byron, Braidwood  |
| Issue date: | 05/01/2013 |
| From: | Gullott D Exelon Generation Co |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| RS-13-099, TAC ME9134, TAC ME9135, TAC ME9136, TAC ME9137 | |
| Download: ML13122A046 (5) | |
Text
1 4300 Winfield Road 4300 Winfield Road Warrenville, IL Warrenville. IL 60555 60555 Exelon Generation(~)Generation. 630 657 630 657 2000 2000 Office RS-1 3-099 10 CFR CFR 50.90 May 1, May 1,2013 2013 U. S. Nuclear Nuclear Regulatory Regulatory Commission Commission ATTN:
A TIN: Document Control Control Desk Washington,DC Washington, DC 20555-0001 Braidwood Braidwood Station, Station, Units Units 1 and 2 Facility Operating License Facility Operating License Nos. Nos.NPF-72 NPF-72 and and NPF-77 NPF-77 NRC Docket Nos. Nos. STN 50 50-456
-456 andand STN 50-457 Byron Byron Station, Station, Units Units 1 and 2 Facility FacilityOperating Operating License LicenseNos.Nos.NPF-37 NPF-37 and and NPF-66 NPF-66 NRC Docket Docket Nos.
Nos. STNSTN 50-454 and and STN 50-455 50-455
Subject:
Response to Request for Additional Additional Information Information Related Related to License Amendment Amendment Request to Revise Technical Specifications Specifications Section 3.5.3, 3.5.3,"ECCS IIECCS- -Shutdown" Shutdown" (T AC Nos.
(TAC Nos. ME9134, ME9134, ME9135, ME9136, and and ME9137)
ME9137)
References:
- 1. Letter from from D.
D. M. Gullott Gullott (Exelon (Exelon Generation Generation Company, Company, LLC LLC (EGC>>(EGC)) to to U. S. NRC, NRC,"License "License Amendment Amendment Request Requestto to Revise ReviseTechnical TechnicalSpecifications Specifications Section Section 3.5.3, 'ECCS -- Shutdown,'"
3.5.3, 'ECCS dated July 23, 2012 Shutdown, I. dated 2012
- 2. Letter from from M. Mahoney (NRC) (NRC) to M.J.J.Pacilio to M. Pacilio(EGC),
(EGC),"Byron "ByronStation,Station, Unit Nos 1 and 2, and Braidwood Braidwood Station, Station, Units Units 1 and and 2 - RequestRequestfor for Additional Information Additional Information Related Related toto License Amendment Request Request to to Revise Revise Specifications (TS)
Technical Specifications (TS) Section Section 3.5.3, 3.5.3, 'ECCS [Emergency Core
'ECCS [Emergency Core Cooling Cooling System]
System] -- Shutdown' Shutdown' (TAC (TAC Nos.
Nos.ME9134, ME9134, ME9135, ME9136,ME9136, and and ME9137),"
ME9137),"
dated March March 28, 2013 In Reference In Reference 1, Exelon Exelon Generation Generation Company, Company, LLC LLC (EGC) requested an an amendment amendment to to the Technical Specifications (TS) (TS) of of Facility Operating License Facility Operating License Nos.
Nos. NPF -72 and NPF-72 and NPF-77 NPF-77 for for Braidwood Station, Units Braidwood Station, Units 11 and and 2,2, and Facility OperatingLicense Facility Operating License Nos.
Nos. NPF-37 NPF-37 and and NPF-66 NPF-66forfor Byron Station, Units Byron Station, Units 11 and and 2. The Thelicense licenseamendment amendmentwould woulddelete deletethe theLimiting LimitingCondition Condition for for Operation (LCO)
Operation (LCO) Note Note associated associated withwith TS TS Section Section3.5.3, 3.5.3,"ECCS Shutdown,"totoreflect "ECCS- -Shutdown," reflectcurrent current plant configurationand plant configuration andensure ensure the the Residual Heat Removal (RHR) system operability (RHR) system operability meets meets the the TS 3.5.3 3.5.3LCO LCO requirement.
requirement. In In Reference Reference2,2,the theNRC NRCrequested requestedthatthatEGC EGCprovide provideadditional additional information information totosupport supporttheir theirreview reviewofofReference Reference1.1. Reference Reference 2 requested requested that that the response responsebe be submitted submitted toto the the NRC NRC within within30 30days days of of the the date date of of the the letter.
letter. However, in a discussion discussion between between Ms. Dwi Murray Murray of ofEGC EGCand and Mr.
Mr.Michael MichaelMahoney Mahoneyof ofthe the NRC NRC on on April April22, 22, 2013, 2013, itit was was agreed agreed
U. S. Nuclear Regulatory Commission May 1, May 1,2013 2013 Page 2 that EGC wouldwould provide the response by May May 1, 1, 2013.
2013. The The information requested in information requested in Reference 2 is provided in the attachment attachment to to this this letter.
letter.
Additionally,the Additionally, the response response to question question 11 ofof the the No No Significant Significant Hazards Hazards Consideration Consideration providedprovided in in the Attachment supersedes supersedes the response to question 1 of the No Significant the response to question 1 of the No Significant Hazards Hazards Consideration provided to the NRC in in Reference 1. While While the the response responsetotoquestion question11ofofthe theNo No Significant Hazards Significant Hazards Consideration determination determination has been been revised revised toto add addclarity, clarity, the the additional additional information provided information provided in inthis this submittal submittal does does not affect the the basis for concluding that the proposed proposed license amendment amendment does doesnot notinvolve involve aasignificant significant hazards hazardsconsideration.
consideration.
In accordance In accordance withwith 10 10 CFR 50 .91, "Notice 50.91, "Notice forfor public comment; State Stateconsultation,"
consultation, II paragraph (b), EGC is providing paragraph providing the State Stateof ofIllinois Illinois with with a copy copy of of this this letter letter and and its its attachment attachment to the designated State State Official.
Official.
There are no no regulatory regulatory commitments contained in this letter.
in this letter. Should you have any questions questions concerning this letter, please please contact contactMs.
Ms.DwiDwi Murray Murray at (630) 657-3695.
II declare declare under penalty of perjury perjury that that the the foregoing foregoing isis true true and and correct.
correct. Executed Executed on on the the1st 1stday day of May 2013.
Respectfully, 721~dY David M.
M. Gullott Manager -- Licensing Licensing Exelon Generation Gel'Jeration Company, LLC
Attachment:
Response to Response toRequest RequestforforAdditional Additional Information Information Related to LicenseLicense Amendment Amendment Request to Request to Revise Revise Technical Technical Specifications SpecificationsSection Section3.5.3, 3.5.3,"ECCS "ECCS- -Shutdown" Shutdown" cc: Regional Administrator -- Region NRC Regional Region III III NRC Senior Resident Inspector -- Braidwood Braidwood Station Station NRC Senior Resident Inspector - Byron Byron Station Station NRC Project Manager, NRR - Braidwood NRC Braidwood and and Byron Byron Stations Stations IllinoisEmergency Illinois Emergency Management Management Agency Agency - DivisionDivision ofof Nuclear Nuclear Safety Safety
ATTACHMENT ATTACHMENT
Response
Responseto toRequest Requestfor forAdditional Additional Information Information Related to License License Amendment Amendment Request Request to Revise Revise Technical Technical Specifications SpecificationsSection Section3.5.3,3.5.3,"ECCS"ECCS- -Shutdown" Shutdown" Question 1:
NRC Question 1:
In Section 4.0, "No In Section Significant Hazards uNo Significant Hazards Consideration",
Consideration",in inresponse response to question question 1. 1. Does Does the change change involve involve aa significant significant increase increase in in the the probability probability or or consequences consequences of ofan an accident previously previously evaluated?,"
evaluated?, the licensee II licenseestates states"Since "Sincethe theECCS ECCSand andRHR RHR systems systems are not accident initiators, initiators, thethe proposed proposed changes changesdo donotnotimpact impactthe theinitiators initiators or or assumptionsof assumptions ofanalyzed analyzed accidents accidents.... ****" II The NRC staff requests the following information information to to complete complete its its review:
review:
- 1. Provide an explanation of accidents accidents that that have haveoccurred occurredthat that were were initiated initiated by by operator error error such such as inappropriate valve as inappropriate valve manipulations. manipulations.
Exelon Generation Company, LLC's LLC's (EGC's) lEGC's) ResponseResponse to toNRCNRC Question Question 1: 1:
EGC recognizes EGC recognizes that there have been been operating operating experiences experienceswithin within our plants and and thethe industry industry where inappropriate inappropriate valvevalve manipulations manipulations have have caused caused system actuations, actuations, drain drain down down events, events, and system system or or component component inoperability.
inoperability. Chapter Chapter15.0 15.0of ofNUREG-0800, NUREG-OBOO, "Standard "Standard Review Review Plan,"
Plan, categorizes a single II single error error of an operator operator as asananexample exampleofofanticipated anticipatedoperational operational occurrences occurrences (AOOs) (ADOs) in pressurized-water reactor (PWR) (PWR) design. AOO ADOas asdefined definedinin10 10CFR CFR Part 50, Appendix A, A, "General "General Design Design Criteria Criteria for forNuclear Nuclear Power Power Plants, Plants," are II are those those conditions conditions of normal of normal operation operation thatthat are are expected to occur one one oror more more times times during during thethe life life of the nuclear power unit.unit. Furthermore, Furthermore, as as described describedininAttachment Attachment11of of Regulatory Regulatory Issue IssueSummary Summary(RIS) (RIS) 2001-022, "Attributes "Attributes of of aa Proposed Proposed No Significant Hazards Consideration Determination," Determination, the II word 'accidents' refers to anticipated (or abnormal) word abnormal) operational transients and and postulated postulateddesign design basis accidents, accidents, including including the events events withwith which which the plant must be able able toto cope cope(e.g.,
(e.g.,
earthquake, flooding, turbine missiles, flooding, turbine missiles, and fire) fire) asas described in in the Updated Updated Final Final Safety Safety Analysis Report Report (UFSAR).
(UFSAR).
Based on the the description description above, above, inappropriate inappropriatevalve valvemanipulation manipulationresulting resultingin in an animpact impactto toRHRRHR system or ECCS operability could be operability could be considered an initiator initiator ofof anan ADO.
AOO. Therefore, EGC EGC hashas revised the response revised response to to question question11of of the theNo No Significant Significant Hazards Hazards Consideration Consideration provided provided in in Reference 1. 1. Specifically, Specifically, thethe original original paragraph paragraphinin Section Section4.3, 4.3,"No"NoSignificant Significant HazardsHazards Consideration," of Consideration," of Reference Reference 1 stated:
"The proposed "The proposed changes changes to to delete deletethe theTS TS3.5.3 3.5.3LCO LCD Note Note will ensure that will ensure that oneone train train of of RHR RHR remains aligned for for ECCS ECCS mode of of operation operation as required to mitigate an accident accident described described in the in the Updated Final Final Safety Safety Analysis Analysis Report Report (UFSAR).
(UFSAR). The The proposed changes changesdo donot notaffect affect the design, operational characteristics, and and function function of of the ECCSECCS and and RHR RHR systems systemsto to mitigate aa design basis mitigate basis accident accident (DBA).
(DBA). Furthermore, Furthermore, the the interfaces interfaces between betweenthe theRHRRHR system and other other plant plant systems' systems'operating operatingfunctions, functions, or or the the reliability reliability of of the the RHR RHR system system are not impacted not impacted by bythe theproposed proposedchanges.
changes. Since Since the ECCS ECCS and RHR RHR systems are not not initiators, the accident initiators, the proposed proposed changes changes do do not notimpact impact the the initiators initiators or assumptions assumptionsof of analyzed accidents, nor nor do do they they impact impact the mitigation mitigation of of accidents accidents or transient events.
Therefore, the ECCS and and RHR RHR systems systemswill will be be capable capableof ofperforming performing their their accident accident mitigationfunctions, mitigation functions,and and the the proposed proposed deletion of the TS 3.5.3 3.5.3 LCOLCD Note does does notnotinvolve involve aa significant increase significant increase in the probability of of anan accident."
Page 1 of 3
ATTACHMENT Response to Response toRequest Requestfor forAdditional AdditionalInformation Related to License Amendment Request Information Related to Revise Technical Specifications Specifications Section Section 3.5.3, "ECCS II ECCS - Shutdown"ll
... Shutdown This paragraph is being revised revised as as follows address the follows to address the NRC NRC question question and and discussion discussion provided above:
"The proposed liThe proposed changes changesto todelete deletethe theTSTS3.5.3 3.S.3LCO LCONote Notewill will ensure ensure thatthat one onetrain train of of RHR RHR remains aligned for ECCS mode of of operation as required to mitigate as required to mitigate an accident described accident described in the in the Updated Final Safety Analysis Analysis Report (UFSAR).(UFSAR). The proposedproposed changeschangesdo donot notaffect affect the ECCS and RHR RHR system design, design, operating operating procedures, procedures,and andadministrative administrative controls controls that that have the function of of preventing preventing or or mitigating mitigatingany anyofofthe thepostulated postulateddesigndesign basisbasis accidents as as described in the UFSAR.UFSAR. Furthermore, Furthermore, the the interfaces interfaces between between the the RHR RHR systemsystem and and other other systems' operating plant systems* operatingfunctions, functions, or orthe thereliability reliability of the RHR system are are not not impacted impactedby by the proposed changes.
changes. The Theproposed proposedchangeschangesdo donotnotchange changeororimpact impactthe theinitiators initiators and assumptions of assumptions of the analyzed analyzed accidents.
accidents. Therefore, Therefore,the theECCS ECCSand andRHRRHRsystemssystemswill will be be capable of capable of performing performing their accident accident mitigation functions, and mitigation functions, and the proposed proposed deletion deletion ofof the the TS 3.5.3 3.S.3 LCO LCO Note does does notnot involve involve aa significant significant increase increase in in the the probability probability of an accident."
accident. II The following response to question 11 of the No Significant following response Hazards Consideration Significant Hazards Consideration supersedes supersedes the entire response responseto toquestion question11of ofthe theNo NoSignificant Significant Hazards Hazards Consideration Consideration previously previously provided in provided in Reference 1: 1:
4.3 No Significant Hazards Consideration Consideration In accordance In accordance with with 10 CFR 50.90,SO.90, Exelon Exelon Generation Generation Company, Company,LLC, LLC, (EGC),
(EGC), is requesting requesting amendments to amendments toFacility Facility Operating Operating License License Nos.Nos. NPF-72 NPF-72and andNPF-77 NPF-77for forBraidwood Braidwood Station, Station, Units 1 and 2, and Units and Facility Facility Operating License Nos. Nos. NPF-37 NPF-37 and and NPF-66 NPF-66for for Byron Byron Station, Units 1 and 2.
Units The proposed proposedchanges changeswill willrevise reviseTechnical TechnicalSpecifications Specifications(TS) (TS)Section Section3.5.3 3.S.3 Limiting LimitingCondition Condition for Operation (LCO)(LCO) forfor Emergency Emergency Core Cooling System System (ECCS)
(ECCS) operability operability requirement requirement in in MODE 44 by MODE by deleting deleting the LCO LCO Note which which allows allows aa Residual Heat Heat Removal Removal (RHR) (RHR) train train to bebe considered operable operable for for ECCS ECCS mode modeof of operation operation when when aligned aligned forfor decay decay heatheatremoval removal operation. The Theproposed proposedchanges changeswill will correct correct aanon-conservative non-conservative TS TS which which may not adequately ensure the ensure the RHR RHR system systemoperability operabilityrequirements requirementsduring duringshutdown shutdowncoolingcoolingoperations operationsinin MODE4.4. The proposed MODE proposed changes changeswill will ensure ensurethatthatone onetrain trainofofRHR RHR remains remains aligned aligned forfor ECCS ECCS mode of operation operation to to satisfy satisfy thethe TS TS 3.S.3 3.5.3 LCO LCOrequirements.
requirements. This This conclusion conclusion isis basedbased on the information provided information provided in in Westinghouse Westinghouse Nuclear Nuclear Safety Safety Advisory Advisory Letter (NSAL) (NSAL) 09-8, 09-8, IIPresence "Presence Vapor in of Vapor in Emergency Emergency Core Cooling System/Residual Heat Heat Removal Removal SystemSysteminin ModesModes3/4 3/4 Loss-of-Coolant Accident Conditions, Conditions,"II dated November November 3, 3, 2009.
2009.
EGC has evaluated evaluatedwhether whetheror ornot notaasignificant significanthazards hazardsconsideration considerationisisinvolvedinvolvedwithwiththethe proposed amendment amendmentby byfocusing focusing on on thethethree threestandards standardsset setforth forthinin1010CFR CFR50.92(c),
SO.92(c),
"Issuance of amendment, IIlssuance amendment,"II as discussed discussedbelow: below:
- 1. Does the changechange involve involve aa significant significant increase increase in in the probability probability or or consequences consequences of of an an accident previously evaluated?
Response: No.
Response: No.
Page 22 of Page of 3
ATTACHMENT Response to Response to Request Requestfor for Additional Additional Information Related to Information Related to License Amendment Request Request to Revise Technical Technical Specifications SpecificationsSectionSection3.5.3, 3.5.3,"ECCS IIECCS--Shutdown" Shutdownll The proposed changes changesto todelete deletethe theTS TS3.5.3 3.5.3LCO LCDNote Notewill will ensure ensurethatthatone onetrain trainofofRHR RHR aligned for remains aligned for ECCS ECCS mode of of operation operation as required required to mitigate mitigate an accident accident described described in the in the Updated Updated Final Final Safety Safety Analysis Analysis Report Report (UFSAR).
(UFSAR). The The proposed changes changesdo donot notaffect affect the ECCS and RHR RHR system design, operatingoperating procedures, procedures, and andadministrative administrative controls controls that that function of have the function of preventing preventing or or mitigating mitigatingany anyofofthe thepostulated postulateddesigndesign basis basis accidents as as described in the UFSAR.
in the UFSAR. Furthermore, Furthermore, the interfaces between between the the RHR RHR system system andandother other plant systems systems'l operating operating functions, functions, oror the the reliability of the reliability of the RHR RHR system are are not not impacted impactedby by the proposed changes. The Theproposed proposedchanges changesdo donotnotchange changeororimpact impactthetheinitiators initiators and and assumptions of the the analyzed analyzed accidents. Therefore, Therefore, the the ECCS ECCS and and RHR RHR systems systemswillwill be capable of performing their accident performing their accident mitigation mitigation functions, functions, andand the proposed proposed deletion deletion ofof the the TS 3.5.3 LCOLCD Note does not not involve involve a significant increase increase in in the the probability probability of an accident.
accident.
changes will The proposed changes will ensure ensure that that one one train train of RHR be available for for ECCS mode of of operation during MODE during MODE to 4 to ensure that the that the RHR RHRsystem, system, as as a subsystem of of ECCS, is operable for ensuring sufficient sufficient ECCS flow is available to the core for for mitigating the consequences of of a loss of coolant accident (LOCA).(LOCA). Thus, the proposed deletion of the TS 3.5.3 LCOLCD Note doesdoes notnot involve significantincrease involve a significant increase in inthetheconsequences consequences of of an accident.
Therefore, the proposed Therefore, proposed changes changesdo donot notinvolve involve aasignificant significant increase increaseininthetheprobability probability or or consequences of consequences of an an accident accidentpreviously previously evaluated.
evaluated.
Reference:
from D.
- 1. Letter from D. M.
M. Gullott Gullott(Exelon (ExelonGeneration Generation Company, LLC LLC (EGC)) to U. u. S. NRC, NRC, "License IlLicense Amendment RequestRequest to to Revise Revise Technical Technical Specifications Specifications Section Section 3.5.3, 3.5.3, 'ECCS IECCS-- Shutdown,"'
Shutdown,1II dated dated July July 23, 23, 2012 2012(ADAMS (ADAMS Accession AccessionNo. No.ML12206A057)
Page Page 33 ofof 33