RS-13-156, Response to Request for Additional Information - Overall Integrated Plan in Response to Commission Order Modifying License Requirements for Reliable Spent Fuel Pool Instrumentation (Order No. EA-12-051)
| ML13186A006 | |
| Person / Time | |
|---|---|
| Site: | Byron  |
| Issue date: | 07/03/2013 |
| From: | Kaegi G Exelon Generation Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| EA-12-051, RS-13-156 | |
| Download: ML13186A006 (15) | |
Text
1 ti RS-13-156 Order No. EA-12-051 EA-12-051 July 3, 2013 3,2013 u.s.
U.S. Nuclear Nuclear Regulatory Regulatory Commission ATTN: Document Control Control Desk Washington, DC 20555-0001 Washington, Byron Station, Byron Station, Units Units 1 and 2 Facility Operating License Nos. Nos. NPF-37 NPF-37 and and NPF-66 NPF-66 NRC Docket Nos. STN 50-454 and STN 50-455
Subject:
Response
Response to to Request Requestfor forAdditional Additional Information Information - Overall Overall Integrated Integrated Plan Plan in in Response
Response
to Commission Order Modifying License Requirements Modifying License Requirements for for Reliable Reliable Spent Spent Fuel Pool Instrumentation Instrumentation (Order (Order No. No. EA-12-051)
References:
Exelon Generation Company, LLC
- 1. Exelon Letter to LLC Letter to USNRC, USNRC,Overall OverallIntegrated Integrated PlanPlan in in Response
Response
to March 12, 2012 Commission Commission Order Order Modifying Modifying Licenses with with Regard to to Requirements Requirements for Reliable Spent Fuel for Reliable Fuel Pool Pool Instrumentation Instrumentation (Order (Order Number NumberEA-1 2-051), dated February EA-12-051), February 28, 2013 (RS-13-028) 28,2013 (RS-13-028)
NRC Order Number EA-12-051,
- 2. NRC Issuance of EA-12-051, Issuance of Order Order to to Modify Licenses with Modify Licenses with Regard Regard to to Reliable Spent Fuel Pool Reliable Pool Instrumentation, Instrumentation, dateddated March March 12,12, 2012 2012
- 3. USNRC letter to Exelon Generation Generation Company, Company,LLC, LLC, Request Requestfor forAdditional Additional Information Information Regarding Overall Overall Integrated Plan for Reliable Reliable Spent Fuel Fuel Pool Pool Instrumentation, Instrumentation, dated dated June 7,2013 7, 2013 In In Reference 1, 1, Exelon Exelon Generation Generation Company, Company,LLC LLC (EGC)
(EGG) provided provided the the Byron Byron Station, Station, Units Units 11 and 2, Overall Overall Integrated Plan Plan in in Response Responsetotothe theMarch March12, 12,2012 CommissionOrder 2012 Commission OrderModifying Modifying Licenses with with Regard to Requirements for Reliable Reliable Spent Fuel Pool Instrumentation, Instrumentation, pursuant to NRC Order No. EA-12-051 NRC EA-12-051 (Reference (Reference 2). 2).
The purpose purpose of of this this letter letter is to provide the response responsetotothetheNRC NRCrequest requestforforadditional additionalinformation information (Reference 3) regarding the Byron Station, Units Byron Station, Units 11 and and 2 Overall Overall Integrated Integrated Plan Plan inin Response Response to to the Commission Order Modifying Licenses with Modifying Licenses with Regard Regard toto Requirements Requirements for for Reliable Reliable Spent Fuel Fuel Pool Instrumentation Pool Instrumentation (Order (Order No.No.EA-12-051).
EA-12-051). Subsequent Subsequent to issuance issuanceof of Reference Reference3, 3,the theNRC NRC identified that identified that Request Request for for Additional Information Item Additional Information Item No.
No. 6.a 6.a was also also applicable applicableto toByron Byron Station, Units Station, Units 1 and and 2.2. This This item item is is included included andand addressed addressedininEnclosure Enclosure11totothis thisletter.
letter.
The Byron Station, Units Byron Station, Units 11 and and 22 Spent Spent Fuel Pool Instrumentation design is proceeding on the Instrumentation design schedule identified schedule identified in in the the Overall Overall Integrated Integrated PlanPlan provided provided ininReference Reference 1. 1. The The enclosed enclosed responses responses to tothe theNRC NRCrequest requestfor foradditional additionalinformation information areare intended intendednot nottotoprovide provide preliminary preliminary or conceptual information.
information. The Therequested requestedinformation, information,whenwhenfully fullydeveloped, developed,will will be beprovided providedupon upon detailed design completion detailed completion based based on on the the milestone milestone schedule schedule dates provided provided in in each each response.
U.S. Nuclear Regulatory Commission Commission Response to Request for Additional Additional Information Information (Order (OrderEA-1 2-051)
July 3, 2013 3,2013 Page 2 This letter contains contains no new regulatory commitments. IfIf you have any questions regulatory commitments. questions regarding regarding this this response, pleasecontact response, please contactDavid David P.P. Helker Helker atat 610-765-5525.
610-765-5525.
II declare perjury that declare under penalty of perjury that the foregoing foregoing is true and correct. Executed Executedon onthe 3rd day the3rd day of of July 2013.
Respectfully submitted, G&iTL~
Glen T. Kaegi Director - Licensing Licensing & Regulatory Affairs Affairs Exelon Generation Company, LLC
Enclosure:
Byron Station,
- 1. Byron Station, Units Units 11 and and 2 - Response ResponsetotoRequest Requestfor forAdditional AdditionalInformation Information -- Overall Overall Integrated Plan in Response Responseto toCommission CommissionOrder OrderModifying Modifying License Requirements Requirements forfor Reliable Spent Fuel Reliable Fuel Pool Pool Instrumentation Instrumentation (Order (OrderNo.
No. EA-12-051)
EA-12-051) cc: Director, Office of Nuclear Reactor Director, Reactor Regulation Regulation NRC Regional Administrator Administrator -- Region Region IIIIII NRC Senior Resident Inspector NRC Inspector -- Byron Byron Station, Units 1 and 2 NRC NRC Project Project Manager, NRR NRR - Byron Byron Station, Units 1 and 22 Mr.
Mr. Robert J. Fretz, Fretz, Jr, Jr, NRRIJLD/PMB, NRRIJLD/PMB, NRC NRC Mr. Robert L.
Mr. L. Dennig, NRRIDSS/SCVB, NRRIDSS/SCVB, NRC NRC Mr.
Mr. Blake Blake Purnell, Purnell, NRC NRC Project Manager, NRR NRR IllinoisEmergency Illinois Emergency Management Management Agency Agency -- Division Division of Nuclear Safety Safety
Enclosure Enclosure 11 Byron Station, Units 11 and 22 Response to Request for Additional Additional Information Information Overall Integrated Plan in Response to Commission Order Modifying Modifying License Requirements for Reliable Reliable Spent Spent Fuel Fuel Pool Pool Instrumentation Instrumentation (Order No. EA-12-051)
(12 pages)
Response to Request for Additional Additional Information Information (Order(OrderEA-1 2-051)
EA-12-051) 1 Enclosure Page 1 of 12 12
1.0 INTRODUCTION
By letter By letter dated dated February February 28, 28, 2013 (Agencywide Documents Access (Agencywide Documents Access and Management Management System System (ADAMS)Accession (ADAMS) Accession No. No. MLML13063A265),
13063A265), Exelon Exelon Generation Generation Company, Company, LLC, LLC, submitted submitted an an overall integrated plan (OIP) overall (OIP) in in response response to to the the March March 12, 2012, U.S.
12,2012, U.S.Nuclear NuclearRegulatory Regulatory Commission (NRC) (NRC) Order modifying licenses with modifying licenses with regard to reliable spent spent fuel fuel pool pool (SFP)
(SFP) instrumentation (Order instrumentation (OrderEA-12-051; EA-12-051; ADAMS ADAMS Accession Accession No. No. ML12054A679)
ML12054A679)for for Byron Byron Station, Station, Unit Nos.
Unit Nos. 1 and and 2. The TheNRC NRC staff staff endorsed endorsedNuclear NuclearEnergyEnergyInstitute, Institute,NEINEI 12-02, 12-02,"Industry "Industry Guidance for Guidance for Compliance Compliance with with NRC NRC Order Order EA-12-051, EA-12-051, to to Modify Modify Licenses Licenses withwith Regard Regardtoto Reliable SFP Instrumentation,"
Reliable Instrumentation," Revision Revision 1, 1, dated datedAugust August2012 2012(ADAMS (ADAMS Accession Accession No. ML No. ML12240A307),
12240A307), with withexceptions exceptions as documented documentedininNRC NRCInterim InterimStaff StaffGuidance, Guidance,JLD-ISG-JLD-ISG-2012-03, "Compliance with Order EA-12-051, EA-12-051, Reliable Spent Spent FuelFuel Pool Pool Instrumentation,"
Instrumentation,"
Revision 0, dated dated August August 29, 2012 (ADAMS 29,2012 (ADAMS Accession AccessionNo. No.ML12221A339).
The NRC staff has NRC staff has reviewed reviewed the the February February 28, 28, 2013, 2013, response response by by the licensee licensee andand determined determined that the following request for additional following request additional information information (RAI) (RAI)isisneeded needed to to complete its technical review.
2.0 LEVELS OF REQUIRED MONITORING The OIP states, in in part, part, that:
that:
Key spent fuel pool water levels levels will will be be identified identified as as follows:
follows:
Level adequate Level adequate to to support supportoperation operationof ofthe thenormal normalfuelfuelpool poolcooling coolingsystem system(Level (Level1):1):
Indicated level Indicated level onon either either primary primary or or backup backup instrument instrument channel of greater than 19 19 feet feet (elevation 419'-2")
(elevation 419'-2")aboveabove thethe top top of ofthe the storage storage racks based based on on the thedesign designaccuracy accuracyofof the instrument channelchannel (which (which is to be determined) determined) and andaaresolution resolutionof of11foot foot oror better betterof of both the primary both primary and and backup instrument channels. This is based based on onSpent SpentFuelFuelPool Pool Cooling Pump Cooling Pump suction suction strainer strainer elevation.
elevation. A A calculation demonstrating adequate calculation demonstrating adequate waterwater level will level willbe beperformed performedas aspart partofofthe thedetailed detailedengineering engineeringdesign design phase phase to ensure ensure thethe level is level is adequate adequate for for normal fuel pool pool cooling cooling system system operation Level adequate Level adequate to provide substantial radiation shielding shielding for for aa person person standing on the spent fuel spent fuel pool operating deck deck (Level (Level 2):
2): Indicated Indicated level level onon either either the the primary primary or or backup backup instrument channel of greater greater than than 10 10 feet feet (elevation (elevation [410'-2"])
[410'-2"]) plus instrument channel accuracy above the top of the storage racks racks based basedon onspecification specification of of this level level asas adequate inin NRC adequate NRC JLD-ISG-2012-03 JLD-ISG-2012-03 and NEI 12-02, the specified design NEI12-02, design accuracy accuracyof of the the instrument channel, and and thethe relatively relatively low sensitivity of low sensitivity of dose dose rates to changes changesinin water water depth at this level.level. This This monitoring monitoring level levelensures ensures there is an adequateadequate waterwater level level to provide substantial provide substantial radiation radiation shielding shielding for foraaperson person standing standing on on the SFP operating operating deckdeck from direct gamma from direct gamma radiation from stored spent spentfuel.
fuel.
Level where Level where fuelfuel remains remains covered (Level (Level 3):3): Indicated Indicated level level on on either either the the primary primary or backup instrument channel of of greater greater than than 00footfoot (elevation (elevation 400'-2")
400'-2") plus plus instrument instrument channel accuracy above the top of of the the storage storage racks basedbased upon upon the design design accuracy accuracy (which isis to (which to bebe determined) determined) of of the the instrument channel for both the primary and backup instrument channels. This This monitoring monitoring levellevel assures assuresthat thatwater waterisiscovering covering the the stored stored fuel seated in seated in the the rack.
rack.
Response to Request Request forfor Additional AdditionalInformation Information(Order (OrderEA-1 2-051)
EA-12-0S1) 1 Enclosure Page 22 of Page of 12 12
RAI-1
Please provide the following:
a) For Level 1, specify how the identified location represents the higher of the two points points described in the NEI NEI 12-02 12-02 guidance guidance for for this this level.
level.
b) A b) clearly labeled A clearly labeled sketch depicting depicting the the elevation elevation view view of of the the proposed proposedtypical typicalmounting mounting arrangement for arrangement for the portions of instrument instrument channel channel consisting consisting of of permanent measurement channel measurement channelequipment equipment(e.g.,(e.g.,fixed fixed level level sensors sensorsand/or and/orstilling stilling wells, wells, and and mounting brackets).
mounting brackets). Indicate Indicate onon this this sketch sketch the thedatum datumvalues valuesrepresenting representingLevel Level1,1, Level 2, Level 2, and Level Level 33 as well well as the the top top ofof the the fuel.
fuel. Indicate Indicateon onthis thissketch sketchthe theportion portionofof the level sensor measurement measurementrange rangethat thatisissensitive sensitiveto to measurement measurementofofthe thefuelfuel pool pool level, with level, with respect respect to the Level Level 1,1, Level Level 2, and and Level Level 33 datum datum points.
points.
Response
a) The Byron Byron Spent Fuel Pool has has two two Spent Spent Fuel Fuel Pool Pool Cooling Cooling Pumps that that take take suction suction from the pool from the pool with with the the top top of ofthe the suction suction strainer strainer at the 417'-9-1/4" elevation. Normal 417'-9-1/4" elevation. Normal Spent Fuel Spent Fuel Pool Pool Level Level is is at the the 424'-6" 424'-6" and and lowlow level level at 424'-2". The Thedetailed detaileddesigndesignwill will calculation to determine adequate include a calculation adequatewater waterlevel level toto maintain maintain normal normal fuelfuel pool pool cooling system operation.
cooling operation. This Thisinformation informationwill will be be available available following following acceptance acceptanceof ofthe the 100% design, scheduled scheduled for for December, 2013. The result will be provided 2013. The result will be provided in the in the February 2014, 6-month Integrated Plan Plan update updatereportreportto tothe theNRC.
NRC.
b) A sketch is provided as Attachment 1, b) 1, "Byron Spent Fuel Fuel Pool Pool Elevation Elevation Sketch."
Sketch."
Instrument probe mounting details details inin the the Spent Spent Fuel Fuel Pool Pool area areawill willbe beprovided providedinin accordance with our our response response to to RAI-3.
RAI-3.
3.0 INSTRUMENTATION DESIGN INSTRUMENTATION DESIGN FEATURES FEATURES 3.2 Arrangement The OIP states, in in part, part, that:
that:
The current plan is to install SFP level install SFP level sensors sensors in in the northwest northwest and and southwest southwest cornerscorners of the of the SFP separated by by aa distance distance in in excess excess of of 20 20 feet. TheThesensors sensorsthemselves themselveswill will be be mounted, to the extent extent practical, practical, near near thethe pool pool walls walls and and below below thethepool poolcurb curb to tominimize minimize their exposure to damaging debris debris andand notnot interfere interfere with with SFP activities.
activities. Instrument Instrument channel electronics and power power supplies supplies will be located in will be in seismic and missile protected areas either areas either below below the the SFP SFPoperating operatingfloor flooror orin in buildings buildings other other than than the theFHB FHB [Fuel [Fuel Handling Building].
Handling Building. The areasareasto tobebeselected selectedwill will provide provide suitable suitable radiation radiation shielding shielding and conditions for environmental conditions for the the equipment consistent with with instrument manufacturer's recommendations. Equipment Equipmentand andcabling cablingfor for power power supplies supplies andandindication indication for for each each channel will be separated will be separated equivalent equivalent to to that that provided provided for for redundant redundant safety safetyrelated related services.
Response to Request for Additional Additional Information Information (Order (OrderEA-12-051)
EA-12-051) 1 Enclosure Page 3 of 12 12
RAI-2
Please provide Please provide aa clearly clearly labeled labeled sketch sketchor ormarked-up marked-upplant plantdrawing drawingof ofthe theplan planview view of of the the SFP SFP area, depicting area, depicting the SFP SFP inside inside dimensions, dimensions, the theplanned plannedlocations/placement locations/placementofofthe theprimary primaryand and back-up SFP level level sensor, sensor, and and the theproposed proposedrouting routingof of the thecables cablesthatthatwillwill extend extend fromfrom thethe sensors sensorstoward toward the thelocation location of of the the read-out/display read-ouVdisplaydevice. device.
Response
A A sketch is provided provided as Attachment Attachment 2, "Byron "Byron Spent Fuel Pool Pool Plan Plan View View Sketch". Note Note thatthatthe the locations ofof the the level level sensors sensors havehave changed changedsince sincethe thesubmittal submittalof ofthe theoverall overall integrated integrated plan.plan.
The detailed design design will include cable will include cable routing routing drawings drawings fromfrom the the Spent Fuel Pool Pool to each each channel indicator.
indicator. The The current current plan for the SFPI for the SFPI design of the system based based on on the the current current Exelon Nuclear Exelon Nuclear program program schedule schedule for for Byron Byron started started the the design design phase phase in in June June2013 2013with with design design completion and completion and 100%
100% acceptance acceptance of the design in December 2013. The Therequested requestedinformation information willbe will be provided provided ininthe the February February 2014, 2014, 6-month 6-month Integrated Plan update. update.
3.3 Mounting 01 P states, in The OIP in part, part, that:
that:
Design of Design of the the mounting mounting of ofthe thesensors sensors in the SFP shall shall be be consistent consistentwith with the the seismic seismic Class II criteria.
criteria. Installed Installed equipment equipment will will be verified verified to to be seismically adequate adequate for for the the seismic motions associatedassociated with with the maximum maximum seismic ground motion considered in the design of of the plant plant area areaininwhich which itit isis installed.
installed.
RAI-3
Please provide the following:
a) The design design criteria criteria that will be used will be used to estimate estimate the the total total loading loading on on the the mounting mounting device(s), including static weight including static weightloads loads and and dynamic dynamic loads.loads. Describe Describe the the methodology methodology that will will bebe used used to estimate estimate the the total total loading, loading, inclusive inclusive of design basis basis maximum maximum seismic seismic loads and and the the hydrodynamic hydrodynamicloads loadsthat thatcould couldresult resultfrom frompool poolsloshing sloshingororother othereff ects effects that could could accompany such such seismic seismic forces.
forces.
b) A b) A description of the manner mannerin in which which the the level level sensor sensor(and(andstilling stillingwell, well,ififappropriate) appropriate)will will be attached attached to to the therefueling refueling floor floor and/or other support support structures structures for for each eachplanned plannedpoint point of attachment of the probe assembly. Indicate of Indicateininaaschematic schematicthe theportions portionsof ofthe thelevel level sensor that sensor that will will serve as as points points of of attachment attachmentfor for mechanical/mounting mechanical/mounting or or electrical electrical connections.
c) A c) description of A description of the the manner manner by by which which the mechanical mechanical connections connectionswill will attach attachthe thelevel level instrument to instrument to permanent permanent SFP structures so so as as toto support support the the level level sensor sensorassembly.
assembly.
Response to Request Request for for Additional Additional Information Information(Order (OrderEA-12-051)
EA-12-0S1) 1 Enclosure Page 4 of 12 12
Response
Device total Device total loading loading and mounting mounting will willbe be performed performed as as part ofof the the detailed design process.
process.
The current plan for the SFPI for the SFPI design of the system based basedon onthethecurrent currentExelon ExelonNuclear Nuclear program schedule for for Byron started the design Byron started design phase phaseininJune June2013 2013with withdesign designcompletion completion and 100%
100% acceptance acceptance of of the the design design inin December December 2013. 2013. The Therequested requestedinformation informationwillwill be be provided in provided in the the February 2014, 2014, 6-month 6-month Integrated Plan update.
3.4 Qualification The OIP alP states, states, in in part, part, that:
that:
Temperature, humidity Temperature, humidity and and radiation radiation levels levelsconsistent consistentwith withconditions conditionsininthe thevicinity vicinity of of the SFP and the the area areaof of use useconsidering considering normalnormal operational, operational, eventevent and and post-event post-event conditions conditions for no fewer for no fewer thanthan seven days days post-event post-event or or until until off-site resources can be off-site resources be deployed deployed by by the the mitigating strategies mitigating strategies resulting from from Order Order EA-12-049 EA-12-049 will willbe beaddressed addressed in in the detailed design phase of phase of the project.
project. Examples Examplesof of post-event post-event (beyond-design-basis)
(beyond-design-basis) conditions conditions toto be be considered are: are:
- radiological conditions for a normal refueling radiological refueling quantity of freshly dischargeddischarged(100(100hour) hour) fuel with fuel with the the SFP SFP water level 3 as as described describedin in Order Order EA-12-051, EA-12-0S1,
- temperature of of 212 degrees FF and and 100%
100% relative relative humidity humidity environment, environment,
- boiling water and/or and/or steam steam environment, environment,
- a concentrated borated borated water water environment, environment, and
- the impact impact of of FLEX mitigating strategies FLEX mitigating strategies [diverse and flexible flexible coping strategies].
For seismic For seismic effects on instrument channel components used usedafter afteraapotential potential seismic seismiceventevent for only installed for only installed components components (with (with thethe exception exception of of battery battery chargers chargers and replaceable replaceable batteries), the following measures will following measures be used to will be to verify that the design and verify that and installation installation is is adequate. Applicable Applicable components components are arerated ratedby bythethemanufacturer manufacturer(or (or otherwise otherwise tested) tested) for for seismic effects effects at levels commensurate with those of postulated with those of postulated design basis event conditions in conditions in the the area of instrument instrument channel component use use using using one oneor ormore moreof of the the following methods:
following methods:
- instrument channel components components use useknown known operating operating principles principles and and are aresupplied supplied by by manufacturers with commercial quality programs with commercial quality programs (such as (such as IS09001). The procurement The procurement specification and/or specification and/or instrument instrument channel channel design shall include include thethe seismic requirements and specify the need need for for commercial design and and testing testing under under seismic seismic loadings loadings consistent with design basis values with design values at at the theinstalled installed locations; locations;
- substantial history substantial historyof of operational operationalreliability reliability inin environments environmentswith withsignificant significantvibration, vibration, such as as for for portable portable hand-held hand-held devices devices or or transportation transportation applications.
applications. Such Such aavibration vibration design envelope envelope shall shall be beinclusive inclusive of of the the effects effects ofof seismic seismic motion motion imparted imparted to to the the components proposed proposed at atthe thelocation location of of the the proposed proposedinstallation; installation;
- adequacy of adequacy of seismic design and installation installation is demonstrated based based onon the the guidance guidancein in Sections 7, Sections 8, 9,9, and 7,8, and10 10ofofIEEE IEEE[Institute
[Institute of of Electrical Electrical andand Electronics Electronics Engineers]
Engineers]
Standard 344-2004, Standard 344-2004,"IEEE "IEEE Recommended RecommendedPractice Practicefor forSeismic SeismicQualification QualificationofofClass Class1 1EE Equipment for Nuclear Power Generating Generating Stations,"
Stations," or oraasubstantially substantiallysimilar similarindustrial industrial standard;
Response to Request Request for for Additional Additional Information Information(Order(OrderEA-1 2-051)
Enclosure 1 Page 5 of 12 12
- demonstration that proposed devices devices arearesubstantially substantiallysimilar similar in in design design to to models models thatthat have been previously previously tested for seismic effects effects in in excess excess of plant design basis at of the plant at the the location where location where the instrument is to be installed (g-levels (g-Ievels and frequency frequency ranges);
ranges); oror
- seismic qualification qualification using using seismic seismic motion motion consistent consistent with that of with that of existing existing design design basis loading at the installation installation location.
location.
RAI-4
Please provide the following:
following:
a) A description of A description of the the specific method or combination of methods methods you you intend intend to to apply applyto to demonstrate the demonstrate the reliability of the reliability of the permanently installed installed equipment under under beyond-design-beyond-design-basis ambient ambient temperature, temperature,humidity, humidity, shock, shock, vibration, vibration, and and radiation radiation conditions.
conditions.
b) A b) description of A description ofthethetesting testing and/or and/or analyses analyses that will be conducted will be conducted to to provide provide assurance assurance that the equipment equipment will perform reliably will perform reliablyunder underthe the worst-case worst-case credible design basis basis loading at loading at the the location location where where the the equipment will willbe bemounted.
mounted. Include Include a discussion discussion of of this seismic reliability demonstration as reliability demonstration as itit applies applies to to a) the level sensor sensor mounted mountedinin thethe SFP area, area, and andb) b) any anycontrol control boxes, boxes, electronics, electronics, or orread-out read-outand andre-transmitting re-transmitting devices devices that will be employed will be employed to convey the level level information information from from the the level level sensor sensor toto the the plant plant operators or emergency responders. responders.
c) A c) description of A description of the the specific specific method or combination of methods methods thatthat will will be used used toto confirm the confirm the reliability reliabilityofofthe the permanently permanently installed equipment equipment suchsuchthatthatfollowing following aa seismic event seismic event the theinstrument instrumentwill will maintain its its required accuracy.
accuracy.
Response
Device qualification Device qualification andand reliability reliabilitywill willbebeperformed performedasaspart partofofthe thedetailed detailed design process. The design process.
for the current plan for the SFPI SFPI design design of of the the system based based on on the thecurrent currentExelon Exelon Nuclear Nuclear program program schedule for Byron schedule started the design phase Byron started phasein in June June2013 2013withwith design designcompletion completion and and100%
100%
acceptance of acceptance of the the design design in in December December2013. 2013. The Therequested requestedinformation informationwill will be beprovided providedin in the the 6-month Integrated Plan update.
February 2014, 6-month 3.5 Independence The OIP states, in in part, part, that:
The primary instrument channel will primary instrument be independent will be independent of the backup instrument instrument channel.
channel.
This independence independence will be will be achieved through physical physical and electrical electrical separation of each channels' components commensuratecommensurate with with hazard and and electrical electrical isolation isolation needs.
RAI-5
Please provide the following:
following:
Response to Response toRequest Requestfor forAdditional AdditionalInformation Information (Order (Order EA-12-051)
EA-12-0S1) 1 Enclosure Page 6 of 12 12 a) A description of A description of how howthe thetwo twochannels channels of ofthe the proposed proposed level level measurement measurement system system meetmeet this requirement so that the potential potential for a common cause cause event eventto to adversely adverselyaffectaffect both both channels isis minimized channels minimized to the extentextent practicable.
practicable.
b) Further information on how each level measurement system, consisting of b) of level level sensor sensor electronics, cabling, and readout devices will be be designed designed and and installed installed to to address address independence through the application and selection selection of of independent independent power power sources, sources, thethe use of physical and spatial separation, independence of of signals signals sent sent toto the the location(s) location(s) of of the readout devices, and the independence of of the the displays.
displays.
Response
Device channel Device channel independence independence evaluation evaluation will be performed as part of the detailed design will be process. The Thecurrent currentplanplanfor for the the SFPI SFPI design designof of the the system systembasedbasedon onthe thecurrent currentExelon Exelon Nuclear program Nuclear program schedule schedule for Byron Byron started started the the design phasephase in in June June2013 2013withwith design design completion and completion and 100%
100% acceptance acceptance of of the design in December 2013. The Therequested requestedinformation information willbe will be provided provided ininthe the February February 2014, 2014, 6-month 6-month Integrated Plan update. update.
3.6 Power supplies The OIP 01 P states, in in part, that:
Each channel channelwill will be normally normally powered powered from from aadifferent different 120Vac 120Vac[120 [120volts-alternating volts-alternating current] bus. Upon current] Uponlosslossofofnormal normalac acpower, power,individual individual channel channelinstalled installedbatteries batterieswill will automatically maintain automatically maintain continuous continuous channel channel operation.
operation. The The batteries batteries will will be replaceable replaceable and be be sized sized toto maintain maintain channel channel operation operation until until off-site off-site resources can be be deployed deployed by by the mitigating strategies strategies resulting resulting from from Order Order EA-12-049.
EA-12-049. Additionally, Additionally, each eachchannel channelwill will have provisions for connection to another another suitable suitable power power source.
source.
RAI-6
Please provide the following:
a) A description of A description of the the electrical electrical acac power sources sources and and capabilities capabilities for for the the primary primary and and backup channels.
b) IfIfthe b) the level levelmeasurement measurement channels are are to to be be powered poweredthroughthrough aabattery batterysystem system(either (either directly or directly or through through an uninterruptible power supply), supply), please please provide provide thethedesign designcriteria criteria that will be applied will be applied to to size size the the battery battery in in aa manner manner that ensures, ensures, withwith margin, that the channel will be available to run reliably and continuously following will be following the the onset onset of the beyond-design-basis event beyond-design-basis event for for the minimum duration needed, consistent minimum duration consistent with with the plant mitigation strategies mitigation strategies forfor beyond-design-basis beyond-design-basis external external events events(Order (OrderEA-12-049).
Response
Device total Device total power power supply supply configuration configurationwill willbebeperformed performedas aspart partofofthe thedetailed detaileddesign design process.
process.
The current plan for for the the SFPI SFPI design of the system based basedon onthe thecurrent currentExelon Exelon Nuclear Nuclear program schedule for program for Byron started the design phase Byron started phasein in June June2013 2013with with design designcompletion completion and and
Response to Request Request for for Additional Additional Information Information(Order (OrderEA-12-051)
EA-12-0S1)
Enclosure 1 Page 7 of 1212 100% acceptance acceptance of of the the design design in in December December2013. 2013.The Therequested requested information informationwillwillbe beprovided provided in in the February 2014, 6-month Integrated Plan update. update.
3.7 Accuracy The OIOIPP states, in part, that:
that:
The instrument channels channels will will be designed designedto to maintain maintain their their design designaccuracy accuracyfollowing following aa power interruption interruption or or change change in power source source without without recalibration.
recalibration. Instrument Instrument channel channel accuracy, to be be determined determined during during detailed detaileddesign, design,willwill consider consider Spent SpentFuel FuelPool Pool conditions (e.g., saturated water, steam environment, conditions (e.g., environment, concentrated borated borated water),
water), as as well as, other applicable radiological well as, radiological and environmental environmental conditions and and include include display display accuracy. Instrument Instrumentchannelchannelaccuracy accuracywill willbe besufficient sufficientto to allow allow trained trained personnel personnelto to determine when the the actual actual level level exceeds exceedsthe thespecified specifiedlowerlowerlevel levelof ofeach eachindicating indicating range (levels (levels 1,1, 22oror3)3) without without conflicting conflicting or ambiguous ambiguousindications.
indications.
RAI-7
Please provide the following:
a) An An estimate of of the expected instrument channel accuracy accuracy performance performance underunderbothboth(a)
(a) normal SFPSFP level level conditions conditions (approximately (approximately Level Level 1 or higher) and and (b)
(b) at at the the beyond beyond design-basis conditions design-basis conditions (i.e.,
(Le., radiation, radiation, temperature, temperature, humidity, humidity, post-seismic post-seismic and andpost-post-shock conditions) that would would be present present ifif the SFP SFP level level were were at atthe theLevel Level 22 and andLevel Level33 datum points.
points.
b) A b) description of A description of the the methodology that will will bebe used for determining the maximum maximum allowed deviation from deviation from thethe instrument instrument channel channel design accuracy accuracy that that will will be employed under under conditions as an normal operating conditions an acceptance acceptancecriterion criterionfor for aacalibration calibration procedure proceduretotoflag flag to operators and to technicians that the channel requires adjustment and to technicians that the channel requires adjustment to within the normal to within the normal condition design condition design accuracy.
Response
Device channel Device channel accuracy analysis will will bebe performed performed as as part ofof the the detailed detailed design process.
process.
The current plan for for the the SFPI SFPI design of the system based of the based on onthe thecurrent currentExelon Exelon Nuclear Nuclear program schedule for Byron program started the design phase Byron started phase inin June June20132013with with design designcompletion completion andand acceptance of 100% acceptance of the design design in in December December 2013. 2013. The Therequested requestedinformation informationwillwill be be provided provided in the in the February 2014, 2014, 6-month 6-month Integrated Integrated Plan update.
3.8 Testing 01 P states, in part, The OIP part, that:
Instrument channel design design will provide for will provide for routine routine testing testing and calibration consistent consistent with with the guidelines of NRC JLD-ISG-2012-03 and NEI NEI 12-02. DetailsDetailswill will be determined determined during detailed during detailed design engineering.
Response to Request for Additional Additional Information Information (Order (OrderEA-12-051)
EA-12-051) 1 Enclosure Page 8 of 12 12
RAI-8
Please provide the following:
a) A A description description of of the the capability capability and and provisions the proposed proposedlevel levelsensing sensingequipment equipmentwill will have to enable enable periodic periodic testing testing and andcalibration, calibration, including including howhow this capability enables enables thethe equipment to be tested tested in-situ.
in-situ.
b) A b) description of A description of how how such such testing and and calibration calibration will will enable the the conduct conductof of regular regular channel checks of each independent channel against the other, other, and against against anyany other other permanently-installed SFP SFP level level instrumentation.
instrumentation.
c) A c) description of A description of how how functional functional checks checks willwillbe be performed, performed, and the frequencyfrequency at at which which they will will bebe conducted.
conducted. Describe Describehow howcalibration calibration tests testswill will be be performed, performed, and andthe the frequency at which frequency which they they will willbebeconducted.
conducted. Provide Provide aa discussion discussion as to how these surveillances will be incorporated into will be into the plant plant surveillance surveillance program.
program.
d) A d) description of A description ofwhat whatpreventative preventativemaintenance maintenance tasks tasks are required required to be be performed performed during normal during normal operation, operation, and the planned planned maximum maximum surveillance surveillance interval interval that that isis necessary to necessary to ensure ensurethatthatthethechannels channelsare arefully fullyconditioned conditionedto toaccurately accuratelyand andreliably reliably perform their perform their functions functions when when needed.
needed.
Response
Device testing Device testing requirement requirement analysis will willbebeperformed performedas as part part of of the the detailed detailed design design process process just just prior to prior to turnover turnovertotoOperations.
Operations. The The current current plan plan for forthe theSFPI SFPIdesign design of ofthe the system system based on on the the current Exelon Nuclear program Exelon Nuclear program schedule schedule for Byron started for Byron started thethe design phase phase in in June June2013 2013with with design completion completion and and 100% acceptance acceptance of of the design in in December 2013. Following Following the issueissue of the of the design, procedures procedureswill will start being being developed developed with with aa projected projected JulyJuly 2014 2014completion completion date. date.
The requested requested information information will be provided will be provided in in the the August August 2014, 2014, 6-month Integrated Plan update. update.
3.9 Display The OIP 01 P states, states, inin part, part, that:
The primary and backup instrument instrument displays displays will will be located at the the control control room, room, alternate alternate shutdown panel, or other appropriate and and accessible accessiblelocation.
location. TheThespecific specificlocation locationwill will be determined during during detailed design. An An appropriate appropriate and andaccessible accessiblelocation locationwillwill include include the following characteristics:
following characteristics:
- occupied or promptly accessible to the promptly accessible the appropriate appropriateplantplantstaff staff giving giving appropriate consideration to various drain down scenarios, scenarios,
- outside the area area surrounding surrounding the the SFP SFPfloor floor (e.g.,
(e.g., an an appropriate appropriatedistance distancefrom from thethe radiological sources radiological sources resulting from from an event impacting impacting the Spent Spent FuelFuel Pool),
Pool),
- inside a structure providing protection against providing protection against adverse adverse weather, and and
- outside of outside of any any very very high highradiation radiationareas areasororLOCKED LOCKEDHIGH HIGHRAD RADAREA AREA during duringnormalnormal operation.
Response totoRequest Response Requestfor forAdditional AdditionalInformation Information(Order (OrderEA-1 2-051)
Enclosure 1 Page 9 of 12 12
RAI-9
Please provide the following:
a) The specific location for for each each of the primary and backup instrument channel primary and channel displays.
displays.
b) IfIfthe b) the primary primary and and backup display location is other than than the the main main control control room, room, provide provide justification forprompt justification for promptaccessibility accessibility to to displays displays including including primary primaryand and alternate alternate route evaluation, habitability habitability atat display location(s),
location(s), continual resource resource availability availability forfor personnel responsible to promptly promptly read displays, displays, and and provisions provisions for for communications communications with with decision makers for the various for the various SFP drain down down scenarios scenarios and external events.
c) The reasons c) reasonsjustifying justifying why the locations selected selected enable enablethe theinformation informationfrom from these these instruments to be considered "promptly accessible" to "promptly accessible" to various various drain-down drain-down scenarios scenarios and external events.
Response
Device channel display location will Device willbebe finalized finalizedduring duringthe thedetailed detaileddesign design process.
process. The Thecurrent current for the plan for the SFPI SFPI design design of the system based basedon onthe thecurrent currentExelon ExelonNuclear Nuclearprogram program schedule schedule for Byron for Byronstarted started the the design design phase in June June 2013 2013 with with design completion completion and and 100%
100% acceptance of the of the design in December 2013. The Therequested requestedinformation informationwillwill be provided provided in the February 2014, 6-month Integrated Plan update.
4.0 PROGRAM FEATURES PROGRAM 4.2 Procedures 01 P states, in The OIP in part, part, that:
that:
Procedures will Procedures be developed will be developed using guidelines and vendor instructions instructions to address address thethe maintenance, operation and abnormal abnormal response responseissues issuesassociated associatedwithwiththe theprimary primaryand and backup channels of of Spent Spent FuelFuel Pool Pool instrumentation.
instrumentation.
RAI-10
Please provide Please provide aa description description of of the the standards, standards,guidelines guidelinesand/or and/orcriteria criteriathat thatwill will be beutilized utilized toto develop procedures for inspection, inspection, maintenance, maintenance, repair, operation, abnormal repair, operation, abnormal response, response, and administrative controls administrative controls associated associated with the SFP level instrumentation, with the instrumentation, as as well as storage well as storage andand installation of portable instruments.
instruments.
Response
Device program Device program features features analysis will be performed will be performed as as part ofof the the detailed detailed design process process justjust prior to prior to turnover turnoverto toOperations.
Operations. The The current current plan plan for forthe theSFPI SFPIdesign design of ofthe the system system basedbased on the the current Exelon Nuclear Nuclear program program schedule schedule for Byron started for Byron started the the design phase phase inin June June20132013with with design completion completion and and 100% acceptance of of the design in in December 2013. FollowingFollowing the issue issue
Response to to Request Request for forAdditional AdditionalInformation Information(Order (OrderEA-1 2-051)
Page 10 10 of 1212 of the design, procedures procedureswill will start start being being developed developedwith with aa projected projectedJuly July2014 2014completion completiondate.
date.
The requested requestedinformation information will be provided in will be in the the August August 2014, 6-month Integrated Plan Plan update.
update.
4.3 Testing and Calibration states, in part, that:
The OIP states, that:
The testing and and calibration calibration of of the the instrumentation instrumentation will will be consistent consistentwith with vendor vendor recommendations or or other documented documented basis. basis.Calibration Calibrationwill will be be specific specific to to the the mounted instruments and the the displays.
displays. Calibration Calibrationwillwill be performed performed to an Instrument Instrument Maintenance Procedure Procedure (BIP/BISR (BIP/BISR series). AAPassport PassportPMID PMIDwill will be be used usedtotodirect direct frequency for performance performance of of the the instrument instrument calibration.
calibration.
RAI-11
Please provide the following:
information describing a) Further information describingthe the maintenance maintenance and testing testing program program the thelicensee licenseewill will establish and and implement implement to ensure ensure thatthat regular regular testing testing andandcalibration calibration is is performed performed and and verified verified byby inspection inspection and and audit audit toto demonstrate demonstrate conformance with with design design and system readiness requirements.
requirements. IncludeIncludeaadescription description of of your your plans plans forfor ensuring that necessary necessary channel checks, checks, functional functional tests, tests, periodic periodic calibration, calibration, and and maintenance maintenancewill will be be conducted conducted for the level measurement system and its supporting for the level measurement system and its supporting equipment. equipment.
b) A description of how the guidance in NEI b) 12-02, Section 4.3 regarding NEI12-02, regarding compensatory compensatory actions for one or both non-functioning channels will be addressed.
c) A c) description of A description ofwhat whatcompensatory compensatory actions actions areare planned in in the event that one one of of the instrument channels cannot be instrument be restored restored to to functional functional status status within within 90 days.
Response
Device testing Device testing and calibration calibration requirements analysis analysis will will be performed as as part part of of the the detailed detailed design process processjustjustprior prior to to turnover to Operations.
Operations. The The current currentplan plan forfor the the SFPI SFPI design designofofthe the system based basedon onthe thecurrent currentExelon Exelon Nuclear Nuclear program program schedule schedulefor for Byron Byron started started thethe design design phase in in June June 2013 2013 with with design completion completion and and 100% acceptance acceptance of of the design in in December 2013. Following Following the issueissue ofof the the design, design, procedures procedureswill will start being being developed developed with with aa projected projected July 2014 completion completion date. The Therequested requestedinformation informationwill will be be provided provided in in the the August August 2014, 2014, 66--
month Integrated month Integrated Plan update.
Response to Request Response Request for for Additional Additional Information (Order EA-12-051)
Information (Order EA-12-051)
Enclosure 1 11 of Page 11 of 12 12 ATTACHMENT1 ATTACHMENT 1 Byron Spent Spent Fuel Fuel Pool Pool Elevation Elevation Sketch Sketch Floor Elevation 426' .IJ'"
-91/2" SpentFuelPool~
~~ormal Level 424'-6 " I-- span 424'-91/2" Le'Ii'el)to 400' -2" (Top of Fuel Rack)
Lo Level 424' ?"
-~ I--
Levell 419'-r I--
Top SFP Pump Suttio1'\
Strainer 417-9-1/4" I--
410' I--
-2"
~
~
-2'~
Fuel Ponl FI1:>or 385'
~ f'.
Nnte:
Response to Request Request for for Additional Additional Information Information(Order (OrderEA-1 2-051)
EA-12-051) 1 Enclosure Page 12 of 12 12 ATTACHMENT A ITACHMENT 22 Byron Spent Fuel PoolPool Plan Plan View View Sketch Sketch Secondary Channel 4-------------- 62'-0" Shipping Shipping Cask Area 33'-1" I Spent Fuel Spent Fuel Pit Pit I Primary Channel Channel w
w
_ _ _ _ _-r_ _ _--. N