ML24225A169
| ML24225A169 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  (DPR-044, DPR-056) |
| Issue date: | 08/12/2024 |
| From: | Para W Constellation Energy Generation |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| Download: ML24225A169 (1) | |
Text
200 Energy Way Kennett Square, PA 19348 www.Constellation.com 10 CFR 50.46 August 12, 2024 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001 Peach Bottom Atomic Power Station, Units 2 and 3 Renewed Facility Operating License Nos. DPR-44 and DPR-56 NRC Docket Nos. 50-277 and 50-278
Subject:
10 CFR 50.46 Annual Report In accordance with 10 CFR 50.46, "Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors," Paragraph (a)(3)(ii), Constellation Energy Generation, LLC (CEG) is submitting this letter and its attachments to meet the annual reporting requirements of the Emergency Core Cooling System (ECCS) Evaluation Model changes and errors for Peach Bottom Atomic Power Station (PBAPS), Units 2 and 3.
There are no regulatory commitments in this letter. If you have any questions concerning this letter, please contact Mr. Steven Bowers at 267-533-5101.
Respectfully, Wendi Para Sr. Manager - Licensing Constellation Energy Generation, LLC Attachments:
- 1. GNF2 Peak Cladding Temperature Rack-Up Sheet for PBAPS Unit 2 2.
GNF3 Peak Cladding Temperature Rack-Up Sheet for PBAPS Unit 2
- 3. GNF2 Peak Cladding Temperature Rack-Up Sheet for PBAPS Unit 3
- 5. Assessment Notes for PBAPS cc:
USNRC Administrator, Region I USNRC Senior Resident Inspector, PBAPS USNRC Project Manager, PBAPS W. DeHaas, Pennsylvania Bureau of Radiation Protection S. Seaman, State of Maryland
- r Constellation.
ATTACHMENT 1 GNF2 Peak Cladding Temperature Rack-Up Sheet for PBAPS Unit 2
AnnualReportoftheEmergencyCoreCoolingSystem EvaluationModelChangesandErrors AssessmentsasofAugust 12,2024 GNF2PeakCladdingTemperatureRackUpSheetforPBAPSUnit2 Page1of1 PLANTNAME:
ECCSEVALUATIONMODEL:
REPORTREVISIONDATE:
EVALUATIONMODELVENDOR:
CURRENTOPERATINGCYCLE:
PeachBottomAtomicPowerStation,Unit2 SAFER/PRIME 08/12/2024 GNF/GEH 25 ANALYSISOFRECORDCALCULATIONS 1.
ProjectTaskReport,ExelonGenerationCompanyLLC,PeachBottomAtomicPower Station,Units2&3MELLLA+TaskT0407:ECCSLOCAPerformance,000001622354R0, Revision0,(PLM000N0296Revision0),December2013.
FuelsAnalyzedinCalculationsandinOperation:
GNF2 LimitingFuelType:
GNF2 LimitingSingleFailure:
BatteryFailure LimitingBreakLocation:
RecirculationDischargeLine LimitingBreakSize 0.05ft2(SmallBreak)
ReferencePeakCladdingTemperature(PCT)forGNF2Fuel:
1920°F MARGINALLOCATION A. PRIORLOCAASSESSMENTS(Note1) 10CFR50.46ReportdatedAugust15,2014(Note1.1)
GNF2:PCT=5°F 10CFR50.46ReportdatedAugust10,2016(Note1.2)
GNF2:PCT=0°F 10CFR50.46ReportdatedAugust10,2017(Note1.3)
GNF2:PCT=0°F 10CFR50.46ReportdatedAugust10,2018(Note1.4)
GNF2:PCT=0°F 10CFR50.46ReportdatedAugust12,2019(Note1.5)
GNF2:PCT=0°F 10CFR50.46ReportdatedAugust12,2020(Note1.6)
GNF2:PCT=0°F 10CFR50.46Report(30DayReport)datedNovember05,2020 (Note1.7)
GNF2:PCT=37°F 10CFR50.46ReportdatedAugust12,2021(Note1.8)
GNF2:PCT=0°F 10CFR50.46ReportdatedAugust12,2022(Note1.9)
GNF2:PCT=0°F 10CFR50.46ReportdatedAugust14,2023(Note1.10)
GNF2:PCT=0°F NetPCT GNF2: 1962°F B. CURRENTLOCAASSESSMENTS(Note2)
TotalPCTChangefromCurrentAssessments(Note2)
GNF2: PCT=0°F CumulativePCTChangefromCurrentAssessments GNF2:lPCTl=0°F NetPCT GNF2: 1962°F
ATTACHMENT 2 GNF3 Peak Cladding Temperature Rack-Up Sheet for PBAPS Unit 2
AnnualReportoftheEmergencyCoreCoolingSystem EvaluationModelChangesandErrors AssessmentsasofAugust 12,2024 GNF3PeakCladdingTemperatureRackUpSheetforPBAPSUnit2 Page1of1 PLANTNAME:
ECCSEVALUATIONMODEL:
REPORTREVISIONDATE:
EVALUATIONMODELVENDOR:
CURRENTOPERATINGCYCLE:
PeachBottomAtomicPowerStation,Unit2 SAFER/PRIME 08/12/2024 GNF/GEH 25 ANALYSISOFRECORDCALCULATIONS 1.
PeachBottomAtomicPowerStationUnits2&3GNF3ECCSLOCAEvaluation,005N9630R0, Revision0,April2021.
FuelsAnalyzedinCalculationsandinOperation:
GNF3 LimitingFuelType:
GNF3 LimitingSingleFailure:
BatteryFailure LimitingBreakLocation:
RecirculationDischargeLine LimitingBreakSize 0.05ft2(SmallBreak)
ReferencePeakCladdingTemperature(PCT)forGNF3Fuel:
2040°F MARGINALLOCATION A. PRIORLOCAASSESSMENTS(Note1) 10CFR50.46ReportdatedAugust14,2023(Note1.10)
GNF3: PCT=0°F NetPCT GNF3: 2040°F B. CURRENTLOCAASSESSMENTS(Note2)
TotalPCTChangefromCurrentAssessments(Note2)
GNF3: PCT=0°F CumulativePCTChangefromCurrentAssessments GNF3: lPCTl=0°F NetPCT GNF3: 2040°F
ATTACHMENT 3 GNF2 Peak Cladding Temperature Rack-Up Sheet for PBAPS Unit 3 AnnualReportoftheEmergencyCoreCoolingSystem EvaluationModelChangesandErrors AssessmentsasofAugust 12,2024 GNF2PeakCladdingTemperatureRackUpSheetforPBAPSUnit3 Page1of1 ANALYSISOFRECORDCALCULATIONS 1.
ProjectTaskReport,ExelonGenerationCompanyLLC,PeachBottomAtomicPower Station,Units2&3MELLLA+TaskT0407:ECCSLOCAPerformance,000001622354R0, Revision0,(PLM000N0296Revision0),December2013.
FuelsAnalyzedinCalculationsandinOperation:
GNF2 LimitingFuelType:
GNF2 LimitingSingleFailure:
BatteryFailure LimitingBreakLocation:
RecirculationDischargeLine LimitingBreakSize 0.05ft2(SmallBreak)
ReferencePeakCladdingTemperature(PCT)forGNF2Fuel:
1920°F MARGINALLOCATION A. PRIORLOCAASSESSMENTS(Note1) 10CFR50.46ReportdatedAugust15,2014(Note1.1)
GNF2: PCT=5°F 10CFR50.46ReportdatedAugust10,2016(Note1.2)
GNF2: PCT=0°F 10CFR50.46ReportdatedAugust10,2017(Note1.3)
GNF2: PCT=0°F 10CFR50.46ReportdatedAugust10,2018(Note1.4)
GNF2: PCT=0°F 10CFR50.46ReportdatedAugust12,2019(Note1.5)
GNF2: PCT=0°F 10CFR50.46ReportdatedAugust12,2020(Note1.6)
GNF2:PCT=0°F 10CFR50.46Report(30DayReport)datedNovember05,2020 (Note1.7)
GNF2: PCT=37°F 10CFR50.46ReportdatedAugust12,2021(Note1.8)
GNF2:PCT=0°F 10CFR50.46ReportdatedAugust12,2022(Note1.9)
GNF2:PCT=0°F 10CFR50.46ReportdatedAugust14,2023(Note1.10)
GNF2:PCT=0°F NetPCT GNF2: 1962°F B. CURRENTLOCAASSESSMENTS(Note2)
TotalPCTChangefromCurrentAssessments(Note2)
GNF2: PCT=0°F CumulativePCTChangefromCurrentAssessments GNF2: lPCTl=0°F NetPCT GNF2: 1962°F PLANTNAME:
ECCSEVALUATIONMODEL:
REPORTREVISIONDATE:
EVALUATIONMODELVENDOR:
CURRENTOPERATINGCYCLE:
PeachBottomAtomicPowerStation,Unit3 SAFER/PRIME 08/12/2024 GNF/GEH 25
ATTACHMENT 4 GNF3 Peak Cladding Temperature Rack-Up Sheet for PBAPS Unit 3
AnnualReportoftheEmergencyCoreCoolingSystem EvaluationModelChangesandErrors AssessmentsasofAugust 12,2024 GNF3PeakCladdingTemperatureRackUpSheetforPBAPSUnit3 Page1of1 PLANTNAME:
ECCSEVALUATIONMODEL:
REPORTREVISIONDATE:
EVALUATIONMODELVENDOR:
CURRENTOPERATINGCYCLE:
PeachBottomAtomicPowerStation,Unit3 SAFER/PRIME 08/12/2024 GNF/GEH 25 ANALYSISOFRECORDCALCULATIONS 1.
PeachBottomAtomicPowerStationUnits2&3GNF3ECCSLOCAEvaluation,005N9630R0,Revision 0,April2021.
FuelsAnalyzedinCalculationsandinOperation:
GNF3 LimitingFuelType:
GNF3 LimitingSingleFailure:
BatteryFailure LimitingBreakLocation:
RecirculationDischargeLine LimitingBreakSize 0.05ft2(SmallBreak)
ReferencePeakCladdingTemperature(PCT)forGNF3Fuel:
2040°F MARGINALLOCATION A. PRIORLOCAASSESSMENTS(Note1) 10CFR50.46ReportdatedAugust12,2022(Note1.9)
GNF3: PCT=0°F 10CFR50.46ReportdatedAugust14,2023(Note1.10)
GNF3: PCT=0°F NetPCT GNF3: 2040°F B. CURRENTLOCAASSESSMENTS(Note2)
TotalPCTChangefromCurrentAssessments(Note2)
GNF3: PCT=0°F CumulativePCTChangefromCurrentAssessments GNF3: lPCTl=0°F NetPCT GNF3: 2040°F
ATTACHMENT 5 Assessment Notes for PBAPS AnnualReportoftheEmergencyCoreCoolingSystem EvaluationModelChangesandErrors AssessmentsasofAugust 12,2024 AssessmentNotesforPBAPS Page1of5 1.
PriorLOCAAssessments Thelast10CFR50.46annualreportwassubmittedtotheU.S.NRConAugust14,2023(Reference1).This reportdocumentsaGNF2fuelNetPCTof1962°F;aLicensingBasisPCTof1920°Ffromtheanalysisofrecord report,andatotalPCTadderof+42°FatPeachBottomAtomicPowerStation(PBAPS),Units2and3.The reportalsodocumentsaGNF3fuelNetPCTof2040°F;aLicensingBasisPCTof2040°F,andatotalPCTadder of0°FatPeachBottomAtomicPowerStation(PBAPS)Unit3.AllthelistedpriorLOCAassessmentsbeloware documentedinthereferencedletter.
[Reference1:LetterfromDavidP.Helker(ConstellationEnergyGeneration,LLC)toU.S.NuclearRegulatory Commission,10CFR50.46AnnualReport,datedAugust14,2023.]
1.1. PriorLOCAAssessment-2014 Thereferencedletterreportedfourvendornotificationsthatwerereceived.Theerrornotifications reportedinthereferencedletterareapplicabletothePeachBottom2and3MELLLA+LOCAanalysisand arebeingreportedasthenotificationswerereportedpriortoimplementationoftheMELLLA+LOCA analysis.ThenotificationswereissuedsubsequenttotheperformanceoftheMELLLA+LOCAanalysis, butpriortoitsimplementation.
1.
The first notification addressed several accumulated updates to the SAFER04A model. The code maintenance changes had an individually and collectively insignificant effect on calculated peak claddingtemperature.
2.
Thesecondnotificationwasforacorrectiontoalogicerrorthatwasisolated,occurringwithan indicationthattheexpectedsystemsmassdivergedfromthecalculatedactualsystemmass.This error affected the Emergency Core Cooling System (ECCS) flow credited as reaching the core.
Correctionofthiserrorresultedina+10°FPeakCladdingTemperature(PCT)changeforGNF2fuel.
3.
ThethirdnotificationaddressedanerrorwiththeimposedminimumPressureDifferential(p)for dropletflowaboveatwophaselevelinthecore.Thiserrorcouldhaveofferedaninappropriate steamcoolingbenefitabovethecoretwophaselevel.Tocorrectthiserroranexplicitcorepressure dropcalculationwasappliedwithoutregardtodropletconditionresultinginaPCTof10°FforGNF2 fuel.
4.
The fourth notification addressed an incorrect pressure head representation when defining the CounterCurrentFlowLimitation(CCFL).Correctionofthiserrorresultedina+5°FPCTchangefor GNF2fuel.
Notethatthe10CFR50.46notificationsdiscussedinthereferencedreportareapplicabletotheUnit2 andUnit3MELLLA+LOCAanalysisandtheneteffectofthesenotificationsis+5°F
[
Reference:
LetterfromJamesBarstow(ExelonGenerationCompany,LLC)toU.S.NuclearRegulatory Commission,10CFR50.46AnnualReport,datedAugust15,2014.]
AnnualReportoftheEmergencyCoreCoolingSystem EvaluationModelChangesandErrors AssessmentsasofAugust 12,2024 AssessmentNotesforPBAPS Page2of5 1.2. PriorLOCAAssessment-2016 ThereferencedletterreportedthatPeachBottomUnit2andUnit3implementedMaximumExtended LoadLineLimitAnalysisPlus(MELLLA+)forwhichanewLOCAanalysiswasperformed.Unit2andUnit3 transitionedtoMELLLA+operationmidcycleinApril2016andMay2016,respectively.Theerror notificationsreportedinAssessmentNote1.1areapplicabletothePeachBottom2and3MELLLA+
LOCAanalysis.ThenotificationswereissuedsubsequenttotheperformanceoftheMELLLA+LOCA analysis,butpriortoitsimplementation.Notethatthe10CFR50.46reportfrom2015wasissuedprior totheimplementationofthecurrentGNF2AORanddidnotincludeanyNotificationLettersapplicable tothecurrentAOR.
[
Reference:
LetterfromJamesBarstow(ExelonGenerationCompany,LLC)toU.S.NuclearRegulatory Commission,"10CFR50.46AnnualReport,"datedAugust10,2016.]
1.3. PriorLOCAAssessment-2017 ThereferencedletterreportedtwovendornotificationsregardingEmergencyCoreCoolingSystem (ECCS)modelingchanges/errorsapplicabletoPeachBottom(Notifications201701and201702).These notificationsdescribedissuesrelatedtotheimpropermodellingoflowertieplateleakagefortheGNF2 fueldesignandchangestomodelingofthefuelrodplenumfor10x10fuel.Correctionoftheseerrors eachresultedina0°FPCTchangeforGNF2fuel.
ThereferencedletterreportedachangeintheLevel3setpoint.TheimpactofthischangeontheLossof CoolantAccident(LOCA)analysiswasassessedinGNFReport003N4534R0,"PeachBottomLevel3 AnalyticalLimitReduction,"datedMay25,2016,whichconcludedthatthereisnoimpactonthe licensingbasisPCTforPeachBottom.
[
Reference:
LetterfromDavidT.Gudger(ExelonGenerationCompany,LLC)toU.S.NuclearRegulatory Commission,10CFR50.46AnnualReport,datedAugust10,2017.]
1.4. PriorLOCAAssessment-2018 Thereferencedletterreportednochanges/errorsagainstthePBAPSLOCAAnalysisofRecordduringthis reportingperiod.
[
Reference:
LetterfromDavidT.Gudger(ExelonGenerationCompany,LLC)toU.S.NuclearRegulatory Commission,10CFR50.46AnnualReport,datedAugust10,2018.]
1.5. PriorLOCAAssessment-2019 Thereferencedletterreportednochanges/errorsagainstthePBAPSLOCAAnalysisofRecordduringthis reportingperiod.
[
Reference:
LetterfromDavidT.Gudger(ExelonGenerationCompany,LLC)toU.S.NuclearRegulatory Commission,10CFR50.46AnnualReport,datedAugust12,2019.]
AnnualReportoftheEmergencyCoreCoolingSystem EvaluationModelChangesandErrors AssessmentsasofAugust 12,2024 AssessmentNotesforPBAPS Page3of5 1.6. PriorLOCAAssessment-2020 Thereferencedletterreportedtwovendornotifications:
Notification201905identifiedthattheupperandlowerlimitsfortheSAFERcodeforwardand backwardbypassleakagewerecodedincorrectlyforthecontrolrodguidetubetocontrolroddrive housinginterfacebackwardleakagepath.TheerrorwasestimatedtohavezerodegreeupontheGNF2 PCT.
Notification202001identifiedthatthePRIMEcodecontainederrorsinirradiationgrowthaftera breakawayneutronfluence,thermalconductivityappliedtothezirconiumbarrierforcladding temperaturedrop,andgapconductanceduringpelletcladdinggapclosure.Theerrorswereestimated tohavezerodegreeimpactupontheGNF2PCT.
[
Reference:
LetterfromDavidP.Helker(ExelonGenerationCompany,LLC)toU.S.NuclearRegulatory Commission,10CFR50.46AnnualReport,datedAugust12,2020.]
1.7. PriorLOCAAssessment-2020(30DayReport)
Thereferencedletterreportedtwovendornotifications:
NotificationLetter(NL)202002documentedthatthevendorimpactevaluationperformedinNL2014 01wasincorrect,andNL202002providesanupdatedimpactevaluationforoneoftheissuesreported inNL201401.NL201401(AssessmentNote1.1)reportsseveralchanges,oneofwhichisregardingthe SAFERcodeerrorregardingthesubcooledwaterlevelinthedowncomer.PerNL202002,theimpact evaluationperformedfor201401wasinaccurate,especiallyforpostulatedLOCAscenarioswherea twophaselevelestablishesinthedowncomer,anexpectedresponseforsmallrecirculationlinebreak scenarios.ThePeachBottomLOCAanalysisissmallbreaklimitedasdocumentedinAttachments1and 2,andhence,NL202002impactedthePeachBottomLOCAanalysis.
NL202002wasissuedbythevendorasanewnotificationwithaPCTimpactof35oF.Thiswasthefirst NLforPeachBottomsincethe2020annualreport(AssessmentNote1.6),andtheabsolutevalueofthe reportedimpactwaslessthan50oF,therefore,typicallythisNLwouldnthaverequiredathirtyday reportingper10CFR50.46(a)(3)(ii).However,asdocumentedinNL202002,whilethisnotificationdid notaltertheSAFERcodeusedinthePeachBottomLOCAevaluation(Attachments1and2),itdidalter thePCTimpactfromtheSAFERcodechangeasreportedinNL201401.Therefore,NL202002 effectivelyamendedNL201401forPBAPS.
AnnualReportoftheEmergencyCoreCoolingSystem EvaluationModelChangesandErrors AssessmentsasofAugust 12,2024 AssessmentNotesforPBAPS Page4of5 SinceNL202002notificationeffectivelyamended201401,thethirtydayreportingrequirementwas evaluatedbasedupontheconditionsapplicablewhennotification201401wasinitiallyissued.
AssessmentNote1.1documentsfournotificationsreportedonAugust15,2014.Thosefournotifications were:
201401=0°F,
201402=10°F,
201403=10°F,and,
201404=5°F.
withatotalimpactof25°F(=0+10+l10l+5).Whenthereported201401value(0°F)iscorrected withtheupdatedvaluefromNL202002(35°F),thetotalimpactbecomes60°F(=35+10+l10l+5),
whichislargerthanthe50°Fsignificancethresholddefinedin10CFR50.46(a)(3)(i)forthirtyday reporting.Therefore,thisthirtydayreportwaspreparedforPBAPSforNL202002.
Notification202003identifiedthatthedomepressureinputusedforAppendixKcalculationsinthe currentLOCAanalysisofrecord(Attachments1and2)didnotcoveroperationallowedbyTechnical Specifications3.4.10.APCTimpactof+2°FwasreportedinNL202003forcorrectingthedomepressure inputusedintheanalysis.
AsdescribedinthedescriptionofNL202002,thisthirtydayreportwaspreparedforNL202002 receivedon10/07/2020.However,sinceNL202003wasissuedwithinthethirtydayreporting timeframeforNL202002,thisthirtydayreportalsoaddressedNL202003forcompleteandaccurate reporting.
[
Reference:
LetterfromDavidP.Helker(ExelonGenerationCompany,LLC)toU.S.NuclearRegulatory Commission,EmergencyCoreCoolingSystem(ECCS)LossofCoolantAccident(LOCA)10CFR50.4630 DayReport,datedNovember05,2020.]
1.8. PriorLOCAAssessment-2021 Thereferencedletterreportedthreevendornotifications:
Notification202101identifiesanerrorinthefuelrodstressandperforationmodelduetoanincorrect valueusedforthefuelpellettoplenumspringconductanceinput.Theerrorwasaresultofanincorrect conversionfromSIunitsinpreparingtheinputforSAFERanalyses.Theerrorwasestimatedtohavea zerodegreeimpactupontheGNF2PCT.
Notification202102identifiesanerrorintheinnercladdingsurfaceroughnessvalueinthegap conductancemodel.Aninconsistencywasidentifiedbetweentheroughnessvalueusedinthefuel performancemodelPRIMEandtheinputtotheSAFERandTRACGcalculations.Theerrorwasestimated tohaveazerodegreeimpactupontheGNF2PCT.
AnnualReportoftheEmergencyCoreCoolingSystem EvaluationModelChangesandErrors AssessmentsasofAugust 12,2024 AssessmentNotesforPBAPS Page5of5 Notification202103identifiesthatanincorrectLowPressureCoolantInjection(LPCI)flowrate valueatahighpressurepointwasusedintheinputtotheSAFERcalculations.Theerrorwas estimatedtohaveazerodegreeimpactupontheGNF2PCT.
[
Reference:
LetterfromDavidP.Helker(ExelonGenerationCompany,LLC)toU.S.NuclearRegulatory Commission,10CFR50.46AnnualReport,datedAugust12,2021.]
1.9. PriorLOCAAssessment-2022 IssueReport4508795reportsthatachangein2011wasmadetothedecayheat(DH)inputusedin nominalcalculationsfortheSAFERevaluationmodel.TheupdatedDHmodelisabestestimate decayheatcurvebasedonthe1979ANS5.1standardandconsidersSIL636.Thischangewas discoveredduringreviewoftheGNF3NewFuelIntroductionandadditionalvendorassessments estimatedanimpactof0°FupontheGNF2PCT.Thischangewasalreadyincorporatedintotheinitial GNF3LOCAevaluationandthereforehasnoimpactontheGNF3LOCAanalysisofrecord.
[
Reference:
LetterfromDavidP.Helker(ConstellationEnergyGeneration,LLC)toU.S.Nuclear RegulatoryCommission,10CFR50.46AnnualReport,datedAugust12,2022.]
1.10.
PriorLOCAAssessment-2023 Thereferencedletterreportedone(1)NotificationLetter:
NotificationLetter202301identifiesanerrorintheapplicationoftheSAFERevaluationmodel.
PotentialvoidsinECCSpipingcoulddelaywaterenteringthecore,orspargers,whichcouldimpact thePeakCladdingTemperature(PCT).ECCSpipingistypicallyfilledwithliquidwaterfromthe systeminjectionvalvetothevessel.ThesystempressureisoftenabovethelowpressureECCS pumpshutoffheadwhilethesysteminjectionvalveisopeningforsmallbreaks.Whenthisistrueno flowcanpassthroughthefinalcheckvalve.AdelayinECCSinjectioncausedbyapotentialvoidin theECCSpipingafterthefinalcheckvalveisconsideredreportableunderinterpretationof10CFR 50.46becauseitmayimpactthesmallbreakPCTresult.Theerrorwasestimatedtohaveazero degreeimpactupontheGNF2andGNF3PCT.
NoadditionalECCSrelatedchangesormodificationsoccurredatPBAPSthataffectedthe assumptionsintheGNF2orGNF3LOCAanalysisofrecord.
[
Reference:
LetterfromDavidP.Helker(ConstellationEnergyGeneration,LLC)toU.S.Nuclear RegulatoryCommission,10CFR50.46AnnualReport,datedAugust14,2023.]
2.
CurrentLOCAAssessment NonewNotificationLetterswerereceivedfromthefuelvendorsinceissuanceofthelastannualreport (ReferenceinNote1.10).NoECCSrelatedchangesormodificationshaveoccurredatPBAPSthataffected theassumptionsintheGNF2orGNF3LOCAanalysisofrecord.Therefore,thetotalPCTvalueof1962oF forGNF2atPBAPSUnits2and3,andthetotalPCTvalueof2040oFforGNF3atPBAPSUnits2and3 reportedinthelastannualreportisunchangedforthisreport.