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{{#Wiki_filter:REGULATlINFORMATIONDISTRIBUTIO1YSTEM(RIDE)ACCESSIO'AABR19408010220DOC.DATE:94/07/26NOTARIZED:YESDOCKETFACIL:50-315DonaldC.CookNuclearPowerPlant,Unit1,IndianaM0500031550-316DonaldC.CookNuclearPowerPlant,Unit2,IndianaM05000316AUTH.NAMEAUTHORAFFILIATIONFITZPATRICK,E.IndianaMichiganPowerCo.(formerlyIndiana&MichiganEleRECIP.iNAMERECIPIENTAFFILIATIONDocumentControlBranch(DocumentControlDesk)
{{#Wiki_filter:REGULATlINFORMATION DISTRIBUTIO1YSTEM (RIDE)ACCESSIO'A ABR19408010220 DOC.DATE:
94/07/26NOTARIZED:
YESDOCKETFACIL:50-315 DonaldC.CookNuclearPowerPlant,Unit1,IndianaM0500031550-316DonaldC.CookNuclearPowerPlant,Unit2,IndianaM05000316AUTH.NAMEAUTHORAFFILIATION FITZPATRICK,E.
IndianaMichiganPowerCo.(formerly Indiana&MichiganEleRECIP.iNAME RECIPIENT AFFILIATION DocumentControlBranch(Document ControlDesk)


==SUBJECT:==
==SUBJECT:==
ApplicationforamendstolicensesDPR-58sDPR-74,proposingTS,bymodifyingTS4.1.1.4suchthatrequirementtomeasuremoderatortemperaturecoefficientnearendofcyclewillbecomeconditional.DISTRIBUTIONCODE:AOOIDCOPIESRECEIVED:LTR/ENCL/SIZE://+//TITLE:ORSubmittal:GeneralDistributionNOTES:RECIPIENTIDCODE/NAMEPD3-1LAHICKMAN,JINTERNAL:NRR/DE/EELBNRR/DRCH/HICBNRR/DSSA/SPLBNUDOCS-ABSTRACTOGC/HDS2EXTERNAL:NRCPDRCOPIESLTTRENCL1122111111111011RECIPIENTIDCODE/NAMEPD3-1PDNRR/DORS/ONDDNRR/DRPWNRR/DSSA/SRXBOCCBEGILE01NSICCOPIESLTTRENCL111111111NOTETOALL"RIDS"RECIPIENTS:PLEASEHELPUSTOREDUCEWASTE!CONTACTTHEDOCUMENTCONTROLDESK,ROOKIPl-37(EXT.504-2083)TOELIIiIINATEYOURNAMEFROMDISTRIBUTIONLISTSI'ORDOCUMENTSYOUDON"I'EED!TOTALNUMBEROFCOPIESREQUIRED:LTTR16ENCL14 lLll IndianaMichiganPowerCompanyP.O.Box16631Columbus,OH43216ÃAEP:NRC:1028ADonaldC.CookNuclearPlantUnits1and2DocketNos.50-315and50-316LicenseNos.DPR-58andDPR-74PROPOSEDTECHNICALSPECIFICATIONCHANGESFORMODERATORTEMPERATURECOEFFICIENTMEASUREMENTU.S.NuclearRegulatoryCommissionDocumentControlDeskWashington,D.C.20555Attn:Mr.W.T.Russell'July26,1994
Application foramendstolicensesDPR-58sDPR-74,proposing TS,bymodifying TS4.1.1.4suchthatrequirement tomeasuremoderator temperature coefficient nearendofcyclewillbecomeconditional.
DISTRIBUTION CODE:AOOIDCOPIESRECEIVED:LTR
/ENCL/SIZE://+//TITLE:ORSubmittal:
GeneralDistribution NOTES:RECIPIENT IDCODE/NAME PD3-1LAHICKMAN,J INTERNAL:
NRR/DE/EELB NRR/DRCH/HICB NRR/DSSA/SPLB NUDOCS-ABSTRACT OGC/HDS2EXTERNAL:
NRCPDRCOPIESLTTRENCL1122111111111011RECIPIENT IDCODE/NAME PD3-1PDNRR/DORS/ONDD NRR/DRPWNRR/DSSA/SRXB OCCBEGILE01NSICCOPIESLTTRENCL111111111NOTETOALL"RIDS"RECIPIENTS:
PLEASEHELPUSTOREDUCEWASTE!CONTACTTHEDOCUMENTCONTROLDESK,ROOKIPl-37(EXT.504-2083)TOELIIiIINATE YOURNAMEFROMDISTRIBUTION LISTSI'ORDOCUMENTS YOUDON"I'EED!TOTALNUMBEROFCOPIESREQUIRED:
LTTR16ENCL14 lLll IndianaMichiganPowerCompanyP.O.Box16631Columbus, OH43216ÃAEP:NRC:1028A DonaldC.CookNuclearPlantUnits1and2DocketNos.50-315and50-316LicenseNos.DPR-58andDPR-74PROPOSEDTECHNICAL SPECIFICATION CHANGESFORMODERATOR TEMPERATURE COEFFICIENT MEASUREMENT U.S.NuclearRegulatory Commission DocumentControlDeskWashington, D.C.20555Attn:Mr.W.T.Russell'July26,1994


==DearMr.Russell:==
==DearMr.Russell:==
ThisletteranditsattachmentsconstituteanapplicationforamendmenttotheTechnicalSpecifications(T/Ss)forDonaldC.CookNuclearPlantUnits1and2.ChangesareproposedtotheModeratorTemperatureCoefficientsectionoftheT/Ss.Specifically,,weproposetomodifyT/S4.1.1.4suchthattherequirementtomeasurethemoderatortemperaturecoefficient(MTC)neartheendofthecyclewillbecomeconditional.ThetestwillnotbeperformedifspecifiedcoreperformancebenchmarkcriteriaaremetfortheoperatingcycleandtherevisedpredictedMTCislessnegativethantheMTCsurveillancelimitpresentedintheCoreOperationLimitsReport(COLR).WearealsoproposingtoaddT/S6.9.1.12,whichdefinesacyclespecific"MostNegativeModeratorTemperatureCoefficientLimitReport"containinginformationforcalculationoftherevisedpredictedMTC.ThereportwillbefiledandavailableforNRCaudit.ThesechangesarerequestedbecauseitisbelievedthatarelaxationoftheexistingcriteriaforperformingtheMTCmeasurementneartheend-of-cycle(EOC)isjustifiablewhilestillensuringtheEOCMTCiswithinitslimits.The300ppmMTCmeasurementistime-andresource-consuming.Itdisruptsnormaloperationanddecreasestheavailabilityofthepowerplant.IncorporatingthesechangeswouldeliminatethesurveillancewhenitiscertainfromotherindicatorsthattheEOCMTClimitwouldnotbeexceeded.WepreviouslymadeasimilarsubmittalviaAEP:NRC:1028,datedOctober20,1987.Uponreview,however,theNRCconcludedthat"ThistypeofamendmentshouldbehandledasagenericissuedueA,g<gi9408010220940726PDRADGCK05000315PPDR W.T.Russell-2-AEP:NRC:1028Atoitsindustrywideimplications."Asaresult,thiscurrentsubmittalisbasedonthegenericinvestigationperformedbyWestinghouseElectricCorporationanddocumentedinReference1ofAttachment1.ThisdocumentwassubmittedtotheNRCforreviewandapprovalinReference2ofAttachment1.Adescriptionoftheproposedchangesandanalysisconcerningsignificanthazardsconsiderationpursuantto10CFR50.92iscontainedinAttachmentl.Attachment2containstheexistingT/Spagesmarkedtoreflectproposedchanges.Attachment3containstheproposed,revisedT/Spages.WebelievethattheproposedT/Schangeswillnotresultin(1)asignificantchangeintheamountofeffluentthatmightbereleasedoffsite,or(2)asignificantincreaseinindividualorcumulativeoccupationalradiationexposure.TheseproposedT/SchangeshavebeenreviewedandapprovedbythePlantNuclearSafetyReviewCommitteeandbytheNuclearSafetyandDesignReviewCommittee.Incompliancewiththerequirementsof10CFR50.91(b)(1),copiesofthisletteranditsattachmentshavebeentransmittedtoMr.J.R.PadgettoftheMichiganPublicServiceCommissionandtheMichiganDepartmentofPublicHealth.Thisletterissubmittedpursuantto10CFR50.30(b)and,assuch,anoathstatementisattached.Sincerely,E.E.FitzatrickVicePresidentcadAttachmentscc:A.A.BlindG.CharnoffJ.B.Martin-RegionIIINFEMSectionChiefNRCResidentInspectorJ.R.Padgett  
Thisletteranditsattachments constitute anapplication foramendment totheTechnical Specifications (T/Ss)forDonaldC.CookNuclearPlantUnits1and2.ChangesareproposedtotheModerator Temperature Coefficient sectionoftheT/Ss.Specifically,,
~~@1 STATEOFOHIO)COUNTYOFFRANKLIN)E.E.Fitzpatrick,beingdulysworn,deposesandsaysthatheistheVicePresidentoflicenseeIndianaMichiganPowerCompany,thathehasreadtheforgoingPROPOSEDTECHNICALSPECIFICATIONCHANGESFORMODERATORTEMPERATURECOEFFICIENTMEASUREMENTandknowsthecontentsthereof;andthatsaidcontentsaretruetothebestofhisknowledgeandbelief.Subscribedandsworntobeforemethis~~~dayof19~VNOTARYPBLICRITAD.HILL ATTACHMENT1TOAEP:NRC:1028ADESCRIPTIONOFPROPOSEDTECHNICALSPECIFICATIONCHANGESAND10CFR50.92SIGNIFICANTHAZARDSCONSIDERATIONANALYSIS ATTACHMENT1toAEP:NRC:1028APage1DESCRIPTIONOFCHANGES(bothunits)Itisproposedthatsurveillancerequirement4.1.1.4.bbechangedtoallowsuspensionofthe300ppmmoderatortemperaturecoefficient(MTC)measurementprovidedthebenchmarkcriteriaandtherevisedprediction,asdocumentedintheCoreOperatingLimitsReport(COLR),aresatisfied.Thechangealsospecifiesthatthedatarequiredfor,calculationoftherevisedpredictionisprovidedinthe"MostNegativeModeratorTemperatureCoefficientLimitReport,"perT/S6.9.1.12.2.Itisproposedthatadministrativecontrolparagraph6.9.1.12beaddedtodefinethe"MostNegativeModeratorTemperatureCoefficientLimitReport."Thereport,whichwillbemaintainedonfile,includesdatarequiredforthedeterminationoftherevisedpredictionofthe300ppmallrodsout(ARO)atratedthermalpower(RTP)MTCperWCAP-13749,"SafetyEvaluationSupportingtheConditionalExemptionoftheMostNegativeEOLModeratorTemperatureCoefficientMeasurement,"May1993.3.ItisproposedthatWCAP-13749beaddedasreference"e"toadministrativecontrolsection6.9.1.11.2.JUSTIFICATIONFORTHECHANGEPursuantto10CFR50.92,eachapplicationforanamendmenttoanoperatingnuclearplantlicenseorconstructionpermitmustbereviewedtodetermineiftheproposedchangeinvolvesasignificanthazardsconsideration.Theproposedtechnicalspecificationamendmentfortheendoflife(EOL)MTCconditionalexemptionhasbeenreviewedanditisconcludedthatnosignificanthazardsresultfromthisT/Schange.BackgroundForFSARaccidentanalyses,thetransientresponseoftheplantisdependentonreactivityfeedbackeffects,inparticular,themoderatordensitycoefficient(MDC)andtheDopplerpowercoefficient.BecauseofthesensitivityofaccidentanalysisresultstotheMDCvalueassumed,itisimportantthattheactualcoreMDCremainwithintheboundsofthelimitingvaluesassumedintheFSARaccidentanalyses.WhilecoreneutronicsanalyseswillconfirmthattheMDCiswithintheseboundsduringanoperatingcycle,CookNuclearPlantT/SscurrentlyplacelimitsontheMTCduringnormaloperation.MTCmeasurementsareperformedatthebeginningofcycle(BOC)priortoinitialoperationabove5%RTPandatRTPconditionswithinseveneffectivefullpowerdays(EFPD)afterreachinganequilibriumboronconcentrationof300ppm.
weproposetomodifyT/S4.1.1.4suchthattherequirement tomeasurethemoderator temperature coefficient (MTC)neartheendofthecyclewillbecomeconditional.
ATTACHMENT1toAEP:NRC:1028APage2Inordertoensureaboundingaccidentanalysis,theMDCisassumedtobeatitsmostlimitingvaluefortheanalysisconditionsappropriatetoeachaccident.ThemostpositiveMDClimitingvalueisbasedontheEOLcoreconditionscorrespondingtomaximumfuelburnupandminimumboronconcentrationassuming100%RTP.TwodifferentT/SbasesrelatingtheaccidentanalysisMDCtothemostnegativeMTChavebeenpreviouslylicensedforWestinghouseplantsasdescribedinChapter2ofReference1ofthisAttachment.MostaccidentanalysesuseaconstantMDCdesignedtoboundtheMDCattheworstsetofinitialconditionsaswellasatthemostlimitingsetoftransientconditions.ThisvalueofMDCformsthelicensingbasisfortheFSARaccidentanalysisaswellasthebasesforthecurrentEOLMTCT/Srequirements.ConvertingtheMDCusedintheaccidentanalysistoacorrespondingMTCrequiresacalculationwhichaccountsfortherateofchangeofmoderatordensitywithtemperatureattheconditionsofinterest.T/Ssplacebothlimitingconditionforoperation(LCO)[T/S3.1.1.4]andsurveillancerequirement[T/S4.1.1.4]constraintsontheMTC,basedontheaccidentanalysisassumptionsoftheMDC.ThemostnegativbMTCLCOlimitappliestoModes1,2,and3,andrequiresthattheMTCbelessnegativethanthespecifiedlimitvaluefortheARO/EOL/RTPcondition.TodemonstratecompliancewiththemostnegativeMTCLCO,theT/SsurveillancecallsforverificationoftheMTCafter300ppmequilibriumboronconcentrationisobtained.Becausethehotfullpower(HFP)MTCvaluewillgraduallybecomemorenegativewithfurthercoreburnupandboronconcentrationreduction,a300ppmsurveillancerequirementvalueoftheMTCshouldnecessarilybelessnegativethantheEOLLCOlimit.Toaccountforthiseffect,the300ppmsurveillancerequirementvalueissufficientlylessnegativethantheEOLLCOlimitvalue,whichisspecifiedintheCOLR,therebyprovidingassurancethattheLCOlimitwillbemetaslongasthe300ppmsurveillancecriterionismet.Currently,CookNuclearPlantUnits1and2T/SsrequiremeasurementsofMTCatbeginningoflife(BOL)toverifythemostpositiveMTClimitandnearEOLtoverifythemostnegative,MTClimit.AtBOL,themeasurementoftheisothermaltemperaturecoefficient,andsubsequentMTCcalculation,isrelativelysimpletoperform.Themeasurementisdoneathotzeropowerisothermalconditionsandisnotcomplicatedbychangesintheenthalpyriseorthepresenceofxenon.ThemeasurementmadenearEOLdiffersfromtheBOLmeasurementasitisperformedatornearHFPconditions.MTCmeasurementsatHFParemoredifficulttoperformduetosmallvariationsinsolubleboronconcentrationandchangesinxenonconcentrationanddistribution,fueltemperature,andenthalpyrisecreatedbysmallchangesinthecoreaveragepowerduringthemeasurement.Changesineachoftheseparametersmustbeaccuratelyaccountedforwhenreducingthemeasurementdata,oradditionalmeasurementuncertaintieswillbeintroduced.Eventhoughtheseadditionaluncertaintiesmaybesmall,thetotalreactivitychangeassociatedwiththeswinginmoderatortemperatureisalsorelativelysmall.TheresultingMTCmeasurementuncertaintycreatedbyevenasmallchangeinpowerlevelcanthenbecomesignificantand,ifimproperlyaccountedfor,canyieldmisleadingmeasurementresults'naddition,itshouldbementionedthatthe300ppmMTCtestisperformedatapproximately95%power,whichadverselyaffectsplantavailability.Withrespecttohumanresources,thetesttakesupto60man-hours.
Thetestwillnotbeperformed ifspecified coreperformance benchmark criteriaaremetfortheoperating cycleandtherevisedpredicted MTCislessnegativethantheMTCsurveillance limitpresented intheCoreOperation LimitsReport(COLR).Wearealsoproposing toaddT/S6.9.1.12, whichdefinesacyclespecific"MostNegativeModerator Temperature Coefficient LimitReport"containing information forcalculation oftherevisedpredicted MTC.Thereportwillbefiledandavailable forNRCaudit.Thesechangesarerequested becauseitisbelievedthatarelaxation oftheexistingcriteriaforperforming theMTCmeasurement neartheend-of-cycle (EOC)isjustifiable whilestillensuringtheEOCMTCiswithinitslimits.The300ppmMTCmeasurement istime-andresource-consuming.
ATTACHMENT1toAEP:NRC:1028APage3Themethodproposedhere,fordeterminingwhetherthesurveillanceissatisfied,istocalculatearevisedpredictionoftheMTCbasedontheactualcorereactivity,actualaxialpowerdistribution,andMTCpredictivecapabilityofthedesignmodel.IftherevisedpredictedMTCmeetsthesurveillancerequirementandtheperformancecriteriapresentedinTable3-2ofReference1issatisfied,thenthemeasurementisnotrequired.Insummary,theconditionalexemptionfromthemeasurementissoughttoimproveplantavailabilityandminimizedisruptionstonormaloperationoftheCookNuclearPlantunits.AsdocumentedinReferences1and2,ithasbeenconcludedthatplantsafetywillnotbecompromisedbytheconditionalexemptionofthismeasurement.Asaresult,theSignificantHazardsConsiderationEvaluationbelowprovidesjustificationthattheconditionalexemptionfromthemeasurementofthe300ppmMTCdoesnotinvolveanysignificanthazardsconsideration.10CFR50.92SIGNIFICANTHAZARDSCONSIDERATIONANALYSIS10CFR50.92specifiesthattheholderofanoperatinglicense'orconstructionpermitofanuclearpowerfacilityparticipateindeterminingwhetherachangetotheT/Ss/currentlicensingbasis(CLB)involvesasignificanthazardsconsideration.Priortoimplementationofachangetothecurrentlicensingbasis,theNuclearRegulatoryCommissionmustreviewandmakeafinaldetermination,pursuanttotheproceduresin10CFR50.91,thataproposedamendmenttotheoperatinglicenseinvolvesnosignificanthazardsconsiderations.Inordertosatisfactorilycompletethereview,theproposedamendmenttotheCLBmustnot:involveasignificantincreaseintheprobabilityorconsequencesofanaccidentpreviouslyevaluated,2.createthepossibilityofanewordifferentkindofaccidentfromanyaccidentpreviouslyevaluated,or3.involveasignificantreductioninamarginofsafety.TheimpactofthesuggestedT/SchangesontheMTCsurveillanceandCOLRsectionsisevaluatedbelowwithrespecttotheacceptancecriteriafortheaccidentsaddressedinChapter14ofCookNuclearPlantUnits1and2FSAR.NuclearDesignConsiderationsTheconditionalexemptionofthemostnegativeEOLMTCmeasurementmethodologyisdescribedindetailinReference1.TheT/SBasesofthemostnegativeMTCLCOandsurveillancerequirement,andthevaluesof"theselimits,arenotaltered.Instead,arevisedpredictioniscomparedtotheMTCsurveillancerequirementtodetermineifthesurveillancelimitismet.TherevisedpredictionissimplythesumofthepredictedHFP300ppmMTCsurveillancerequirementplusanaxialfluxdifference(AFD)correctionfactorplusapredictivecorrectionterm.Abriefdescriptionofeachofthesetermsisgivenbelow.
Itdisruptsnormaloperation anddecreases theavailability ofthepowerplant.Incorporating thesechangeswouldeliminate thesurveillance whenitiscertainfromotherindicators thattheEOCMTClimitwouldnotbeexceeded.
ATTACHMENT1toAEP:NRC:1028APage4PredictedHFP300ppmsurveillancerequirementMTCAnymispredictionofthecorereactivitybalancebythecoremodelwouldcausethecoretobeataboronconcentrationof300ppmatadifferentcycleburnupthanactual.ThisinturnwouldcauseadifferenceintheactualversuspredictedMTC.ThesensitivityofMTCat300ppmasafunctionofcoreburnupisdeterminedandprovidedaspartoftheMostNegativeMTCLimitReport.AFDCorrectionTheMTCisaffectedbytheAFDviatheimpacttheaxialfluxdistributionhasonthemoderatortemperatureprofile.Themorebottomskewedthepowerdistribution,thehigherthetemperaturesnearthebottomofthecore.Also,theburnupinthebottomhalfofthecoreexceedstheburnupinthetophalf.AhigherburnupwillresultinamorenegativeMTC.Amorebottomskewedaxialpowershapeallocatesagreaterfluxweightingtothelowerregionofthecorewheretheburnupisgreater,therebyaccentuatingtheburnupeffectonMTC.TheMTCsensitivitytoAFDisprovidedintheMTClimitreport.SincemeasuredAFDmustbedeterminedevery31days,thelatestmeasurementcanbecomparedwiththepredictionandthedifferenceobtained.ThisdifferenceisthenusedwiththeAFDsensitivitytoobtainthecorrection.PredictiveCorrectionTermToaccountfortheMTCpredictivecapabilityofthedesignmodelforagivencycle,anadditionalcorrectionwillbeappliedtothepredictedMTCtodeterminethefinalMTCtobecomparedtothesurveillancelimit.Thepredictivecorrectionwillbedefinedas0pcm/'ForthedifferencebetweenthemeasuredandpredictedBOChotzeropowerMTC,whicheverismorenegative.Theconditionalexemptionfromthemeasurementwillbedeterminedonacycle-specificbasis.Thecoremodelperformancemustbebenchmarkedtotheoperatingcorebeforeapplyingtheprocedurefordeterminingtherevisedprediction.ThespecificparameterschosenandtheassociatedcriteriaaregiveninReference1.Meetingthesecriteriademonstratesthecoremodel'scapabilitytoaccuratelypredictchangesinthecorecharacteristicswithdepletion,andthereforeprovideanaccuratepredictionoftheHFP300ppmMTC~SafetyAnalysisConsiderationsThesafetyanalysisassumptionofaconstantMDC,andtheactualvalueassumed,willnotchange.Therefore,aconditionalexemptionfromthe300ppmMTCmeasurementbasedonthemargintothesurveillancelimitwillnothaveanadverseimpactonthesafeoperationoftheplant.
Wepreviously madeasimilarsubmittal viaAEP:NRC:1028, datedOctober20,1987.Uponreview,however,theNRCconcluded that"Thistypeofamendment shouldbehandledasagenericissuedueA,g<gi9408010220 940726PDRADGCK05000315PPDR W.T.Russell-2-AEP:NRC:1028A toitsindustrywideimplications."
ATTACHMENT1toAEP:NRC:1028APage5TechnicalSpecificationImpactsTheproposedT/Ssurveillance4.1.1.4andconcomitantCOLRchangesrequiredtosupporttheconditionalexemptionaredescribedinReference1.TheseT/SchangeswillnotchangetheLCOorsurveillancerequirementMTClimits.ThespecificvaluesofthesurveillancerequirementandLCOMTCsremainunchangedbytheconditionalexemptionmethodologydocumentedinReference1.AnadditionalT/Swillbeadded(6.9.1.12)whichwilldefinethe"MostNegativeModeratorTemperatureCoefficientLimitReport."Thiscycle-specificreportwillprovidetheinformationrequiredforcalculatingthemargintothesurveillancelimit.Reference"e"willalsobeaddedtothelistofreferencesinT/S6.9.1.11.2.DETERMINATIONOFNOSIGNIFICANTHAZARDSDoestheEOLMTCmeasurementconditionalexemptioninvolveasignificantincreaseintheprobabilityorconsequencesofanaccidentpreviouslyevaluated'PNO.TheconditionalexemptionofthemostnegativeMTCmeasurementdoesnotchangethemostnegativeMTCsurveillanceandLCOlimitsintheT/Ss.SincetheseMTCvaluesareunchanged,andsincethebasisforthederivationofthesevaluesfromthesafetyanalysisMDCisunchanged,theconstantMDCassumedfortheFSARsafetyanalyseswillalsoremainunchanged.Therefore,nochangeinthemodeling(i.e.,probabilities)oftheaccidentanalysisconditionsorresponseisnecessaryinordertoimplementthechangetotheconditionalexemptionmethodology.Inaddition,sincetheconstantMDCassumedinthesafetyanalysesisnotchangedbytheconditionalexemptionofthemostnegativeMTCsurveillancemeasurement,theconsequencesofanaccidentpreviouslyevaluatedintheFSARarenotincreased.ThedosepredictionspresentedintheFSARforaSGTRremainvalidsuchthatmoresevereconsequenceswillnotoccur.Additionally,sincemassandenergyreleasesforLOCAandsteamlinebreakarenotincreasedasaresultoftheunchangedMDC,thedosepredictionsfortheseeventspresentedintheFSARalsoremainbounding.Criterion2DoestheEOLMTCmeasurementconditionalexemptioncreatethepossibilityofanewordifferentkindofaccidentfromanyaccidentpreviouslyevaluated'O.SincetheEOLMTCisnotchangedbytheconditionalexemptionmethodologyofReference1,thepossibilityofanaccidentwhichisdifferentthananyalreadyevaluatedintheFSARhasnotbeencreated.Nonewordifferentfailuremodeshavebeendefinedforanysystemorcomponentnorhasanynewlimitingsinglefailurebeen ATTACHMENT1toAEP:NRC:1028APage6identified.ConservativeassumptionsforMDChavealreadybeenmodeledintheFSARanalyses.TheseassumptionswillremainvalidsincetheconditionalexemptionmethodologydocumentedinReference1doesnotchangethesafetyanalysisMDCnortheT/SvaluesoftheMTC.Criterion3DoestheEOLMTCmeasurementconditionalexemptioninvolveasignificantreductioninamarginofsafety'O.TheevaluationoftheconditionalexemptionmethodologydocumentedinReference1hastakenintoaccounttheapplicableCookNuclearPlantUnits1and2T/Ssandhasboundedtheconditionsunderwhichthespecificationspermitoperation.TheapplicableT/Ssaresurveillance4.1.1.4,andreference"e"isaddedtothelistofreferencesinSpecification6.9.1.11.2.Anadditionalspecification6.9.1.12isaddedtodefinetherequirementsforthe"MostNegativeModeratorTemperatureCoefficientLimitReport,"whichisdescribedinAppendicesA,C,andDofReference1.TheCOLRhasalsobeenmodifiedasdescribedinAppendixBofReference1,TheanalyseswhichsupporttheseT/Sshavebeenevaluated.Theresults,aspresentedintheFSAR,remainboundingsincetheMDCassumedinthesafetyanalysesandtheLCOandsurveillancerequirementMTCsintheT/Ssremainunchanged.Therefore,themarginofsafety,asdefinedinthebasestotheseT/Ss,isnotreduced.ConclusionItisconcludedthatoperationofCookNuclearPlantUnits1and2withaconditionalexemptionfromthemostnegativeMTCmeasurement,asdescribedinReference1andthisevaluation,doesnotinvolveanysignificanthazardsasdefinedin10CFR50.92.References1.WCAP-13749-P,"SafetyEvaluationSupportingTheConditionalExemptionoftheMostNegativeEOLModeratorTemperatureCoefficientMeasurement,"May1993.2,LetterET-NRC-93-3894,fromNicholasJ.Liparulo,ManagerNuclearSafetyandRegulatoryActivitiesofWestinghouseElectricCorporationtoR.C.Jones,ReactorSystemsBranchChief,DivisionofEngineeringandSystemTechnologyofUSNRC,datedJune1,1993.
Asaresult,thiscurrentsubmittal isbasedonthegenericinvestigation performed byWestinghouse ElectricCorporation anddocumented inReference 1ofAttachment 1.Thisdocumentwassubmitted totheNRCforreviewandapprovalinReference 2ofAttachment 1.Adescription oftheproposedchangesandanalysisconcerning significant hazardsconsideration pursuantto10CFR50.92iscontained inAttachment l.Attachment 2containstheexistingT/Spagesmarkedtoreflectproposedchanges.Attachment 3containstheproposed, revisedT/Spages.WebelievethattheproposedT/Schangeswillnotresultin(1)asignificant changeintheamountofeffluentthatmightbereleasedoffsite,or(2)asignificant increaseinindividual orcumulative occupational radiation exposure.
ATTACHMENT2TOAEP:NRC:1028AEXISTINGTECHNICALSPECIFICATIONPAGESMARKEDTOREFLECTPROPOSEDCHANGES}}
TheseproposedT/SchangeshavebeenreviewedandapprovedbythePlantNuclearSafetyReviewCommittee andbytheNuclearSafetyandDesignReviewCommittee.
Incompliance withtherequirements of10CFR50.91(b)(1),
copiesofthisletteranditsattachments havebeentransmitted toMr.J.R.PadgettoftheMichiganPublicServiceCommission andtheMichiganDepartment ofPublicHealth.Thisletterissubmitted pursuantto10CFR50.30(b)and,assuch,anoathstatement isattached.
Sincerely, E.E.FitzatrickVicePresident cadAttachments cc:A.A.BlindG.CharnoffJ.B.Martin-RegionIIINFEMSectionChiefNRCResidentInspector J.R.Padgett  
~~@1 STATEOFOHIO)COUNTYOFFRANKLIN)
E.E.Fitzpatrick, beingdulysworn,deposesandsaysthatheistheVicePresident oflicenseeIndianaMichiganPowerCompany,thathehasreadtheforgoingPROPOSEDTECHNICAL SPECIFICATION CHANGESFORMODERATOR TEMPERATURE COEFFICIENT MEASUREMENT andknowsthecontentsthereof;andthatsaidcontentsaretruetothebestofhisknowledge andbelief.Subscribed andsworntobeforemethis~~~dayof19~VNOTARYPBLICRITAD.HILL ATTACHMENT 1TOAEP:NRC:1028A DESCRIPTION OFPROPOSEDTECHNICAL SPECIFICATION CHANGESAND10CFR50.92SIGNIFICANT HAZARDSCONSIDERATION ANALYSIS ATTACHMENT 1toAEP:NRC:1028A Page1DESCRIPTION OFCHANGES(bothunits)Itisproposedthatsurveillance requirement 4.1.1.4.b bechangedtoallowsuspension ofthe300ppmmoderator temperature coefficient (MTC)measurement providedthebenchmark criteriaandtherevisedprediction, asdocumented intheCoreOperating LimitsReport(COLR),aresatisfied.
Thechangealsospecifies thatthedatarequiredfor,calculation oftherevisedprediction isprovidedinthe"MostNegativeModerator Temperature Coefficient LimitReport,"perT/S6.9.1.12.
2.Itisproposedthatadministrative controlparagraph 6.9.1.12beaddedtodefinethe"MostNegativeModerator Temperature Coefficient LimitReport."Thereport,whichwillbemaintained onfile,includesdatarequiredforthedetermination oftherevisedprediction ofthe300ppmallrodsout(ARO)atratedthermalpower(RTP)MTCperWCAP-13749, "SafetyEvaluation Supporting theConditional Exemption oftheMostNegativeEOLModerator Temperature Coefficient Measurement,"
May1993.3.ItisproposedthatWCAP-13749 beaddedasreference "e"toadministrative controlsection6.9.1.11.2.
JUSTIFICATION FORTHECHANGEPursuantto10CFR50.92,eachapplication foranamendment toanoperating nuclearplantlicenseorconstruction permitmustbereviewedtodetermine iftheproposedchangeinvolvesasignificant hazardsconsideration.
Theproposedtechnical specification amendment fortheendoflife(EOL)MTCconditional exemption hasbeenreviewedanditisconcluded thatnosignificant hazardsresultfromthisT/Schange.Background ForFSARaccidentanalyses, thetransient responseoftheplantisdependent onreactivity feedbackeffects,inparticular, themoderator densitycoefficient (MDC)andtheDopplerpowercoefficient.
Becauseofthesensitivity ofaccidentanalysisresultstotheMDCvalueassumed,itisimportant thattheactualcoreMDCremainwithintheboundsofthelimitingvaluesassumedintheFSARaccidentanalyses.
Whilecoreneutronics analyseswillconfirmthattheMDCiswithintheseboundsduringanoperating cycle,CookNuclearPlantT/Sscurrently placelimitsontheMTCduringnormaloperation.
MTCmeasurements areperformed atthebeginning ofcycle(BOC)priortoinitialoperation above5%RTPandatRTPconditions withinseveneffective fullpowerdays(EFPD)afterreachinganequilibrium boronconcentration of300ppm.
ATTACHMENT 1toAEP:NRC:1028A Page2Inordertoensureaboundingaccidentanalysis, theMDCisassumedtobeatitsmostlimitingvaluefortheanalysisconditions appropriate toeachaccident.
ThemostpositiveMDClimitingvalueisbasedontheEOLcoreconditions corresponding tomaximumfuelburnupandminimumboronconcentration assuming100%RTP.Twodifferent T/SbasesrelatingtheaccidentanalysisMDCtothemostnegativeMTChavebeenpreviously licensedforWestinghouse plantsasdescribed inChapter2ofReference 1ofthisAttachment.
MostaccidentanalysesuseaconstantMDCdesignedtoboundtheMDCattheworstsetofinitialconditions aswellasatthemostlimitingsetoftransient conditions.
ThisvalueofMDCformsthelicensing basisfortheFSARaccidentanalysisaswellasthebasesforthecurrentEOLMTCT/Srequirements.
Converting theMDCusedintheaccidentanalysistoacorresponding MTCrequiresacalculation whichaccountsfortherateofchangeofmoderator densitywithtemperature attheconditions ofinterest.
T/Ssplacebothlimitingcondition foroperation (LCO)[T/S3.1.1.4]andsurveillance requirement
[T/S4.1.1.4]constraints ontheMTC,basedontheaccidentanalysisassumptions oftheMDC.ThemostnegativbMTCLCOlimitappliestoModes1,2,and3,andrequiresthattheMTCbelessnegativethanthespecified limitvaluefortheARO/EOL/RTP condition.
Todemonstrate compliance withthemostnegativeMTCLCO,theT/Ssurveillance callsforverification oftheMTCafter300ppmequilibrium boronconcentration isobtained.
Becausethehotfullpower(HFP)MTCvaluewillgradually becomemorenegativewithfurthercoreburnupandboronconcentration reduction, a300ppmsurveillance requirement valueoftheMTCshouldnecessarily belessnegativethantheEOLLCOlimit.Toaccountforthiseffect,the300ppmsurveillance requirement valueissufficiently lessnegativethantheEOLLCOlimitvalue,whichisspecified intheCOLR,therebyproviding assurance thattheLCOlimitwillbemetaslongasthe300ppmsurveillance criterion ismet.Currently, CookNuclearPlantUnits1and2T/Ssrequiremeasurements ofMTCatbeginning oflife(BOL)toverifythemostpositiveMTClimitandnearEOLtoverifythemostnegative,MTC limit.AtBOL,themeasurement oftheisothermal temperature coefficient, andsubsequent MTCcalculation, isrelatively simpletoperform.Themeasurement isdoneathotzeropowerisothermal conditions andisnotcomplicated bychangesintheenthalpyriseorthepresenceofxenon.Themeasurement madenearEOLdiffersfromtheBOLmeasurement asitisperformed atornearHFPconditions.
MTCmeasurements atHFParemoredifficult toperformduetosmallvariations insolubleboronconcentration andchangesinxenonconcentration anddistribution, fueltemperature, andenthalpyrisecreatedbysmallchangesinthecoreaveragepowerduringthemeasurement.
Changesineachoftheseparameters mustbeaccurately accounted forwhenreducingthemeasurement data,oradditional measurement uncertainties willbeintroduced.
Eventhoughtheseadditional uncertainties maybesmall,thetotalreactivity changeassociated withtheswinginmoderator temperature isalsorelatively small.Theresulting MTCmeasurement uncertainty createdbyevenasmallchangeinpowerlevelcanthenbecomesignificant and,ifimproperly accounted for,canyieldmisleading measurement results'n
: addition, itshouldbementioned thatthe300ppmMTCtestisperformed atapproximately 95%power,whichadversely affectsplantavailability.
Withrespecttohumanresources, thetesttakesupto60man-hours.
ATTACHMENT 1toAEP:NRC:1028A Page3Themethodproposedhere,fordetermining whetherthesurveillance issatisfied, istocalculate arevisedprediction oftheMTCbasedontheactualcorereactivity, actualaxialpowerdistribution, andMTCpredictive capability ofthedesignmodel.Iftherevisedpredicted MTCmeetsthesurveillance requirement andtheperformance criteriapresented inTable3-2ofReference 1issatisfied, thenthemeasurement isnotrequired.
Insummary,theconditional exemption fromthemeasurement issoughttoimproveplantavailability andminimizedisruptions tonormaloperation oftheCookNuclearPlantunits.Asdocumented inReferences 1and2,ithasbeenconcluded thatplantsafetywillnotbecompromised bytheconditional exemption ofthismeasurement.
Asaresult,theSignificant HazardsConsideration Evaluation belowprovidesjustification thattheconditional exemption fromthemeasurement ofthe300ppmMTCdoesnotinvolveanysignificant hazardsconsideration.
10CFR50.92SIGNIFICANT HAZARDSCONSIDERATION ANALYSIS10CFR50.92specifies thattheholderofanoperating license'or construction permitofanuclearpowerfacilityparticipate indetermining whetherachangetotheT/Ss/current licensing basis(CLB)involvesasignificant hazardsconsideration.
Priortoimplementation ofachangetothecurrentlicensing basis,theNuclearRegulatory Commission mustreviewandmakeafinaldetermination, pursuanttotheprocedures in10CFR50.91,thataproposedamendment totheoperating licenseinvolvesnosignificant hazardsconsiderations.
Inordertosatisfactorily completethereview,theproposedamendment totheCLBmustnot:involveasignificant increaseintheprobability orconsequences ofanaccidentpreviously evaluated, 2.createthepossibility ofanewordifferent kindofaccidentfromanyaccidentpreviously evaluated, or3.involveasignificant reduction inamarginofsafety.Theimpactofthesuggested T/SchangesontheMTCsurveillance andCOLRsectionsisevaluated belowwithrespecttotheacceptance criteriafortheaccidents addressed inChapter14ofCookNuclearPlantUnits1and2FSAR.NuclearDesignConsiderations Theconditional exemption ofthemostnegativeEOLMTCmeasurement methodology isdescribed indetailinReference 1.TheT/SBasesofthemostnegativeMTCLCOandsurveillance requirement, andthevaluesof"theselimits,arenotaltered.Instead,arevisedprediction iscomparedtotheMTCsurveillance requirement todetermine ifthesurveillance limitismet.Therevisedprediction issimplythesumofthepredicted HFP300ppmMTCsurveillance requirement plusanaxialfluxdifference (AFD)correction factorplusapredictive correction term.Abriefdescription ofeachofthesetermsisgivenbelow.
ATTACHMENT 1toAEP:NRC:1028A Page4Predicted HFP300ppmsurveillance requirement MTCAnymisprediction ofthecorereactivity balancebythecoremodelwouldcausethecoretobeataboronconcentration of300ppmatadifferent cycleburnupthanactual.Thisinturnwouldcauseadifference intheactualversuspredicted MTC.Thesensitivity ofMTCat300ppmasafunctionofcoreburnupisdetermined andprovidedaspartoftheMostNegativeMTCLimitReport.AFDCorrection TheMTCisaffectedbytheAFDviatheimpacttheaxialfluxdistribution hasonthemoderator temperature profile.Themorebottomskewedthepowerdistribution, thehigherthetemperatures nearthebottomofthecore.Also,theburnupinthebottomhalfofthecoreexceedstheburnupinthetophalf.AhigherburnupwillresultinamorenegativeMTC.Amorebottomskewedaxialpowershapeallocates agreaterfluxweighting tothelowerregionofthecorewheretheburnupisgreater,therebyaccentuating theburnupeffectonMTC.TheMTCsensitivity toAFDisprovidedintheMTClimitreport.SincemeasuredAFDmustbedetermined every31days,thelatestmeasurement canbecomparedwiththeprediction andthedifference obtained.
Thisdifference isthenusedwiththeAFDsensitivity toobtainthecorrection.
Predictive Correction TermToaccountfortheMTCpredictive capability ofthedesignmodelforagivencycle,anadditional correction willbeappliedtothepredicted MTCtodetermine thefinalMTCtobecomparedtothesurveillance limit.Thepredictive correction willbedefinedas0pcm/'Forthedifference betweenthemeasuredandpredicted BOChotzeropowerMTC,whichever ismorenegative.
Theconditional exemption fromthemeasurement willbedetermined onacycle-specific basis.Thecoremodelperformance mustbebenchmarked totheoperating corebeforeapplyingtheprocedure fordetermining therevisedprediction.
Thespecificparameters chosenandtheassociated criteriaaregiveninReference 1.Meetingthesecriteriademonstrates thecoremodel'scapability toaccurately predictchangesinthecorecharacteristics withdepletion, andtherefore provideanaccurateprediction oftheHFP300ppmMTC~SafetyAnalysisConsiderations Thesafetyanalysisassumption ofaconstantMDC,andtheactualvalueassumed,willnotchange.Therefore, aconditional exemption fromthe300ppmMTCmeasurement basedonthemargintothesurveillance limitwillnothaveanadverseimpactonthesafeoperation oftheplant.
ATTACHMENT 1toAEP:NRC:1028A Page5Technical Specification ImpactsTheproposedT/Ssurveillance 4.1.1.4andconcomitant COLRchangesrequiredtosupporttheconditional exemption aredescribed inReference 1.TheseT/SchangeswillnotchangetheLCOorsurveillance requirement MTClimits.Thespecificvaluesofthesurveillance requirement andLCOMTCsremainunchanged bytheconditional exemption methodology documented inReference 1.Anadditional T/Swillbeadded(6.9.1.12) whichwilldefinethe"MostNegativeModerator Temperature Coefficient LimitReport."Thiscycle-specific reportwillprovidetheinformation requiredforcalculating themargintothesurveillance limit.Reference "e"willalsobeaddedtothelistofreferences inT/S6.9.1.11.2.
DETERMINATION OFNOSIGNIFICANT HAZARDSDoestheEOLMTCmeasurement conditional exemption involveasignificant increaseintheprobability orconsequences ofanaccidentpreviously evaluated'P NO.Theconditional exemption ofthemostnegativeMTCmeasurement doesnotchangethemostnegativeMTCsurveillance andLCOlimitsintheT/Ss.SincetheseMTCvaluesareunchanged, andsincethebasisforthederivation ofthesevaluesfromthesafetyanalysisMDCisunchanged, theconstantMDCassumedfortheFSARsafetyanalyseswillalsoremainunchanged.
Therefore, nochangeinthemodeling(i.e.,probabilities) oftheaccidentanalysisconditions orresponseisnecessary inordertoimplement thechangetotheconditional exemption methodology.
Inaddition, sincetheconstantMDCassumedinthesafetyanalysesisnotchangedbytheconditional exemption ofthemostnegativeMTCsurveillance measurement, theconsequences ofanaccidentpreviously evaluated intheFSARarenotincreased.
Thedosepredictions presented intheFSARforaSGTRremainvalidsuchthatmoresevereconsequences willnotoccur.Additionally, sincemassandenergyreleasesforLOCAandsteamline breakarenotincreased asaresultoftheunchanged MDC,thedosepredictions fortheseeventspresented intheFSARalsoremainbounding.
Criterion 2DoestheEOLMTCmeasurement conditional exemption createthepossibility ofanewordifferent kindofaccidentfromanyaccidentpreviously evaluated'O.
SincetheEOLMTCisnotchangedbytheconditional exemption methodology ofReference 1,thepossibility ofanaccidentwhichisdifferent thananyalreadyevaluated intheFSARhasnotbeencreated.Nonewordifferent failuremodeshavebeendefinedforanysystemorcomponent norhasanynewlimitingsinglefailurebeen ATTACHMENT 1toAEP:NRC:1028A Page6identified.Conservative assumptions forMDChavealreadybeenmodeledintheFSARanalyses.
Theseassumptions willremainvalidsincetheconditional exemption methodology documented inReference 1doesnotchangethesafetyanalysisMDCnortheT/SvaluesoftheMTC.Criterion 3DoestheEOLMTCmeasurement conditional exemption involveasignificant reduction inamarginofsafety'O.
Theevaluation oftheconditional exemption methodology documented inReference 1hastakenintoaccounttheapplicable CookNuclearPlantUnits1and2T/Ssandhasboundedtheconditions underwhichthespecifications permitoperation.
Theapplicable T/Ssaresurveillance 4.1.1.4,andreference "e"isaddedtothelistofreferences inSpecification 6.9.1.11.2.
Anadditional specification 6.9.1.12isaddedtodefinetherequirements forthe"MostNegativeModerator Temperature Coefficient LimitReport,"whichisdescribed inAppendices A,C,andDofReference 1.TheCOLRhasalsobeenmodifiedasdescribed inAppendixBofReference 1,TheanalyseswhichsupporttheseT/Sshavebeenevaluated.
Theresults,aspresented intheFSAR,remainboundingsincetheMDCassumedinthesafetyanalysesandtheLCOandsurveillance requirement MTCsintheT/Ssremainunchanged.
Therefore, themarginofsafety,asdefinedinthebasestotheseT/Ss,isnotreduced.Conclusion Itisconcluded thatoperation ofCookNuclearPlantUnits1and2withaconditional exemption fromthemostnegativeMTCmeasurement, asdescribed inReference 1andthisevaluation, doesnotinvolveanysignificant hazardsasdefinedin10CFR50.92.References 1.WCAP-13749-P, "SafetyEvaluation Supporting TheConditional Exemption oftheMostNegativeEOLModerator Temperature Coefficient Measurement,"
May1993.2,LetterET-NRC-93-3894, fromNicholasJ.Liparulo, ManagerNuclearSafetyandRegulatory Activities ofWestinghouse ElectricCorporation toR.C.Jones,ReactorSystemsBranchChief,DivisionofEngineering andSystemTechnology ofUSNRC,datedJune1,1993.
ATTACHMENT 2TOAEP:NRC:1028A EXISTINGTECHNICAL SPECIFICATION PAGESMARKEDTOREFLECTPROPOSEDCHANGES}}

Revision as of 07:10, 29 June 2018

Application for Amends to Licenses DPR-58 & DPR-74,proposing Ts,By Modifying TS 4.1.1.4 Such That Requirement to Measure Moderator Temperature Coefficient Near End of Cycle Will Become Conditional
ML17332A229
Person / Time
Site: Cook  American Electric Power icon.png
Issue date: 07/26/1994
From: FITZPATRICK E
INDIANA MICHIGAN POWER CO. (FORMERLY INDIANA & MICHIG
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
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ML17332A230 List:
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AEP:NRC:1028A, NUDOCS 9408010220
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Text

REGULATlINFORMATION DISTRIBUTIO1YSTEM (RIDE)ACCESSIO'A ABR19408010220 DOC.DATE:

94/07/26NOTARIZED:

YESDOCKETFACIL:50-315 DonaldC.CookNuclearPowerPlant,Unit1,IndianaM0500031550-316DonaldC.CookNuclearPowerPlant,Unit2,IndianaM05000316AUTH.NAMEAUTHORAFFILIATION FITZPATRICK,E.

IndianaMichiganPowerCo.(formerly Indiana&MichiganEleRECIP.iNAME RECIPIENT AFFILIATION DocumentControlBranch(Document ControlDesk)

SUBJECT:

Application foramendstolicensesDPR-58sDPR-74,proposing TS,bymodifying TS4.1.1.4suchthatrequirement tomeasuremoderator temperature coefficient nearendofcyclewillbecomeconditional.

DISTRIBUTION CODE:AOOIDCOPIESRECEIVED:LTR

/ENCL/SIZE://+//TITLE:ORSubmittal:

GeneralDistribution NOTES:RECIPIENT IDCODE/NAME PD3-1LAHICKMAN,J INTERNAL:

NRR/DE/EELB NRR/DRCH/HICB NRR/DSSA/SPLB NUDOCS-ABSTRACT OGC/HDS2EXTERNAL:

NRCPDRCOPIESLTTRENCL1122111111111011RECIPIENT IDCODE/NAME PD3-1PDNRR/DORS/ONDD NRR/DRPWNRR/DSSA/SRXB OCCBEGILE01NSICCOPIESLTTRENCL111111111NOTETOALL"RIDS"RECIPIENTS:

PLEASEHELPUSTOREDUCEWASTE!CONTACTTHEDOCUMENTCONTROLDESK,ROOKIPl-37(EXT.504-2083)TOELIIiIINATE YOURNAMEFROMDISTRIBUTION LISTSI'ORDOCUMENTS YOUDON"I'EED!TOTALNUMBEROFCOPIESREQUIRED:

LTTR16ENCL14 lLll IndianaMichiganPowerCompanyP.O.Box16631Columbus, OH43216ÃAEP:NRC:1028A DonaldC.CookNuclearPlantUnits1and2DocketNos.50-315and50-316LicenseNos.DPR-58andDPR-74PROPOSEDTECHNICAL SPECIFICATION CHANGESFORMODERATOR TEMPERATURE COEFFICIENT MEASUREMENT U.S.NuclearRegulatory Commission DocumentControlDeskWashington, D.C.20555Attn:Mr.W.T.Russell'July26,1994

DearMr.Russell:

Thisletteranditsattachments constitute anapplication foramendment totheTechnical Specifications (T/Ss)forDonaldC.CookNuclearPlantUnits1and2.ChangesareproposedtotheModerator Temperature Coefficient sectionoftheT/Ss.Specifically,,

weproposetomodifyT/S4.1.1.4suchthattherequirement tomeasurethemoderator temperature coefficient (MTC)neartheendofthecyclewillbecomeconditional.

Thetestwillnotbeperformed ifspecified coreperformance benchmark criteriaaremetfortheoperating cycleandtherevisedpredicted MTCislessnegativethantheMTCsurveillance limitpresented intheCoreOperation LimitsReport(COLR).Wearealsoproposing toaddT/S6.9.1.12, whichdefinesacyclespecific"MostNegativeModerator Temperature Coefficient LimitReport"containing information forcalculation oftherevisedpredicted MTC.Thereportwillbefiledandavailable forNRCaudit.Thesechangesarerequested becauseitisbelievedthatarelaxation oftheexistingcriteriaforperforming theMTCmeasurement neartheend-of-cycle (EOC)isjustifiable whilestillensuringtheEOCMTCiswithinitslimits.The300ppmMTCmeasurement istime-andresource-consuming.

Itdisruptsnormaloperation anddecreases theavailability ofthepowerplant.Incorporating thesechangeswouldeliminate thesurveillance whenitiscertainfromotherindicators thattheEOCMTClimitwouldnotbeexceeded.

Wepreviously madeasimilarsubmittal viaAEP:NRC:1028, datedOctober20,1987.Uponreview,however,theNRCconcluded that"Thistypeofamendment shouldbehandledasagenericissuedueA,g<gi9408010220 940726PDRADGCK05000315PPDR W.T.Russell-2-AEP:NRC:1028A toitsindustrywideimplications."

Asaresult,thiscurrentsubmittal isbasedonthegenericinvestigation performed byWestinghouse ElectricCorporation anddocumented inReference 1ofAttachment 1.Thisdocumentwassubmitted totheNRCforreviewandapprovalinReference 2ofAttachment 1.Adescription oftheproposedchangesandanalysisconcerning significant hazardsconsideration pursuantto10CFR50.92iscontained inAttachment l.Attachment 2containstheexistingT/Spagesmarkedtoreflectproposedchanges.Attachment 3containstheproposed, revisedT/Spages.WebelievethattheproposedT/Schangeswillnotresultin(1)asignificant changeintheamountofeffluentthatmightbereleasedoffsite,or(2)asignificant increaseinindividual orcumulative occupational radiation exposure.

TheseproposedT/SchangeshavebeenreviewedandapprovedbythePlantNuclearSafetyReviewCommittee andbytheNuclearSafetyandDesignReviewCommittee.

Incompliance withtherequirements of10CFR50.91(b)(1),

copiesofthisletteranditsattachments havebeentransmitted toMr.J.R.PadgettoftheMichiganPublicServiceCommission andtheMichiganDepartment ofPublicHealth.Thisletterissubmitted pursuantto10CFR50.30(b)and,assuch,anoathstatement isattached.

Sincerely, E.E.FitzatrickVicePresident cadAttachments cc:A.A.BlindG.CharnoffJ.B.Martin-RegionIIINFEMSectionChiefNRCResidentInspector J.R.Padgett

~~@1 STATEOFOHIO)COUNTYOFFRANKLIN)

E.E.Fitzpatrick, beingdulysworn,deposesandsaysthatheistheVicePresident oflicenseeIndianaMichiganPowerCompany,thathehasreadtheforgoingPROPOSEDTECHNICAL SPECIFICATION CHANGESFORMODERATOR TEMPERATURE COEFFICIENT MEASUREMENT andknowsthecontentsthereof;andthatsaidcontentsaretruetothebestofhisknowledge andbelief.Subscribed andsworntobeforemethis~~~dayof19~VNOTARYPBLICRITAD.HILL ATTACHMENT 1TOAEP:NRC:1028A DESCRIPTION OFPROPOSEDTECHNICAL SPECIFICATION CHANGESAND10CFR50.92SIGNIFICANT HAZARDSCONSIDERATION ANALYSIS ATTACHMENT 1toAEP:NRC:1028A Page1DESCRIPTION OFCHANGES(bothunits)Itisproposedthatsurveillance requirement 4.1.1.4.b bechangedtoallowsuspension ofthe300ppmmoderator temperature coefficient (MTC)measurement providedthebenchmark criteriaandtherevisedprediction, asdocumented intheCoreOperating LimitsReport(COLR),aresatisfied.

Thechangealsospecifies thatthedatarequiredfor,calculation oftherevisedprediction isprovidedinthe"MostNegativeModerator Temperature Coefficient LimitReport,"perT/S6.9.1.12.

2.Itisproposedthatadministrative controlparagraph 6.9.1.12beaddedtodefinethe"MostNegativeModerator Temperature Coefficient LimitReport."Thereport,whichwillbemaintained onfile,includesdatarequiredforthedetermination oftherevisedprediction ofthe300ppmallrodsout(ARO)atratedthermalpower(RTP)MTCperWCAP-13749, "SafetyEvaluation Supporting theConditional Exemption oftheMostNegativeEOLModerator Temperature Coefficient Measurement,"

May1993.3.ItisproposedthatWCAP-13749 beaddedasreference "e"toadministrative controlsection6.9.1.11.2.

JUSTIFICATION FORTHECHANGEPursuantto10CFR50.92,eachapplication foranamendment toanoperating nuclearplantlicenseorconstruction permitmustbereviewedtodetermine iftheproposedchangeinvolvesasignificant hazardsconsideration.

Theproposedtechnical specification amendment fortheendoflife(EOL)MTCconditional exemption hasbeenreviewedanditisconcluded thatnosignificant hazardsresultfromthisT/Schange.Background ForFSARaccidentanalyses, thetransient responseoftheplantisdependent onreactivity feedbackeffects,inparticular, themoderator densitycoefficient (MDC)andtheDopplerpowercoefficient.

Becauseofthesensitivity ofaccidentanalysisresultstotheMDCvalueassumed,itisimportant thattheactualcoreMDCremainwithintheboundsofthelimitingvaluesassumedintheFSARaccidentanalyses.

Whilecoreneutronics analyseswillconfirmthattheMDCiswithintheseboundsduringanoperating cycle,CookNuclearPlantT/Sscurrently placelimitsontheMTCduringnormaloperation.

MTCmeasurements areperformed atthebeginning ofcycle(BOC)priortoinitialoperation above5%RTPandatRTPconditions withinseveneffective fullpowerdays(EFPD)afterreachinganequilibrium boronconcentration of300ppm.

ATTACHMENT 1toAEP:NRC:1028A Page2Inordertoensureaboundingaccidentanalysis, theMDCisassumedtobeatitsmostlimitingvaluefortheanalysisconditions appropriate toeachaccident.

ThemostpositiveMDClimitingvalueisbasedontheEOLcoreconditions corresponding tomaximumfuelburnupandminimumboronconcentration assuming100%RTP.Twodifferent T/SbasesrelatingtheaccidentanalysisMDCtothemostnegativeMTChavebeenpreviously licensedforWestinghouse plantsasdescribed inChapter2ofReference 1ofthisAttachment.

MostaccidentanalysesuseaconstantMDCdesignedtoboundtheMDCattheworstsetofinitialconditions aswellasatthemostlimitingsetoftransient conditions.

ThisvalueofMDCformsthelicensing basisfortheFSARaccidentanalysisaswellasthebasesforthecurrentEOLMTCT/Srequirements.

Converting theMDCusedintheaccidentanalysistoacorresponding MTCrequiresacalculation whichaccountsfortherateofchangeofmoderator densitywithtemperature attheconditions ofinterest.

T/Ssplacebothlimitingcondition foroperation (LCO)[T/S3.1.1.4]andsurveillance requirement

[T/S4.1.1.4]constraints ontheMTC,basedontheaccidentanalysisassumptions oftheMDC.ThemostnegativbMTCLCOlimitappliestoModes1,2,and3,andrequiresthattheMTCbelessnegativethanthespecified limitvaluefortheARO/EOL/RTP condition.

Todemonstrate compliance withthemostnegativeMTCLCO,theT/Ssurveillance callsforverification oftheMTCafter300ppmequilibrium boronconcentration isobtained.

Becausethehotfullpower(HFP)MTCvaluewillgradually becomemorenegativewithfurthercoreburnupandboronconcentration reduction, a300ppmsurveillance requirement valueoftheMTCshouldnecessarily belessnegativethantheEOLLCOlimit.Toaccountforthiseffect,the300ppmsurveillance requirement valueissufficiently lessnegativethantheEOLLCOlimitvalue,whichisspecified intheCOLR,therebyproviding assurance thattheLCOlimitwillbemetaslongasthe300ppmsurveillance criterion ismet.Currently, CookNuclearPlantUnits1and2T/Ssrequiremeasurements ofMTCatbeginning oflife(BOL)toverifythemostpositiveMTClimitandnearEOLtoverifythemostnegative,MTC limit.AtBOL,themeasurement oftheisothermal temperature coefficient, andsubsequent MTCcalculation, isrelatively simpletoperform.Themeasurement isdoneathotzeropowerisothermal conditions andisnotcomplicated bychangesintheenthalpyriseorthepresenceofxenon.Themeasurement madenearEOLdiffersfromtheBOLmeasurement asitisperformed atornearHFPconditions.

MTCmeasurements atHFParemoredifficult toperformduetosmallvariations insolubleboronconcentration andchangesinxenonconcentration anddistribution, fueltemperature, andenthalpyrisecreatedbysmallchangesinthecoreaveragepowerduringthemeasurement.

Changesineachoftheseparameters mustbeaccurately accounted forwhenreducingthemeasurement data,oradditional measurement uncertainties willbeintroduced.

Eventhoughtheseadditional uncertainties maybesmall,thetotalreactivity changeassociated withtheswinginmoderator temperature isalsorelatively small.Theresulting MTCmeasurement uncertainty createdbyevenasmallchangeinpowerlevelcanthenbecomesignificant and,ifimproperly accounted for,canyieldmisleading measurement results'n

addition, itshouldbementioned thatthe300ppmMTCtestisperformed atapproximately 95%power,whichadversely affectsplantavailability.

Withrespecttohumanresources, thetesttakesupto60man-hours.

ATTACHMENT 1toAEP:NRC:1028A Page3Themethodproposedhere,fordetermining whetherthesurveillance issatisfied, istocalculate arevisedprediction oftheMTCbasedontheactualcorereactivity, actualaxialpowerdistribution, andMTCpredictive capability ofthedesignmodel.Iftherevisedpredicted MTCmeetsthesurveillance requirement andtheperformance criteriapresented inTable3-2ofReference 1issatisfied, thenthemeasurement isnotrequired.

Insummary,theconditional exemption fromthemeasurement issoughttoimproveplantavailability andminimizedisruptions tonormaloperation oftheCookNuclearPlantunits.Asdocumented inReferences 1and2,ithasbeenconcluded thatplantsafetywillnotbecompromised bytheconditional exemption ofthismeasurement.

Asaresult,theSignificant HazardsConsideration Evaluation belowprovidesjustification thattheconditional exemption fromthemeasurement ofthe300ppmMTCdoesnotinvolveanysignificant hazardsconsideration.

10CFR50.92SIGNIFICANT HAZARDSCONSIDERATION ANALYSIS10CFR50.92specifies thattheholderofanoperating license'or construction permitofanuclearpowerfacilityparticipate indetermining whetherachangetotheT/Ss/current licensing basis(CLB)involvesasignificant hazardsconsideration.

Priortoimplementation ofachangetothecurrentlicensing basis,theNuclearRegulatory Commission mustreviewandmakeafinaldetermination, pursuanttotheprocedures in10CFR50.91,thataproposedamendment totheoperating licenseinvolvesnosignificant hazardsconsiderations.

Inordertosatisfactorily completethereview,theproposedamendment totheCLBmustnot:involveasignificant increaseintheprobability orconsequences ofanaccidentpreviously evaluated, 2.createthepossibility ofanewordifferent kindofaccidentfromanyaccidentpreviously evaluated, or3.involveasignificant reduction inamarginofsafety.Theimpactofthesuggested T/SchangesontheMTCsurveillance andCOLRsectionsisevaluated belowwithrespecttotheacceptance criteriafortheaccidents addressed inChapter14ofCookNuclearPlantUnits1and2FSAR.NuclearDesignConsiderations Theconditional exemption ofthemostnegativeEOLMTCmeasurement methodology isdescribed indetailinReference 1.TheT/SBasesofthemostnegativeMTCLCOandsurveillance requirement, andthevaluesof"theselimits,arenotaltered.Instead,arevisedprediction iscomparedtotheMTCsurveillance requirement todetermine ifthesurveillance limitismet.Therevisedprediction issimplythesumofthepredicted HFP300ppmMTCsurveillance requirement plusanaxialfluxdifference (AFD)correction factorplusapredictive correction term.Abriefdescription ofeachofthesetermsisgivenbelow.

ATTACHMENT 1toAEP:NRC:1028A Page4Predicted HFP300ppmsurveillance requirement MTCAnymisprediction ofthecorereactivity balancebythecoremodelwouldcausethecoretobeataboronconcentration of300ppmatadifferent cycleburnupthanactual.Thisinturnwouldcauseadifference intheactualversuspredicted MTC.Thesensitivity ofMTCat300ppmasafunctionofcoreburnupisdetermined andprovidedaspartoftheMostNegativeMTCLimitReport.AFDCorrection TheMTCisaffectedbytheAFDviatheimpacttheaxialfluxdistribution hasonthemoderator temperature profile.Themorebottomskewedthepowerdistribution, thehigherthetemperatures nearthebottomofthecore.Also,theburnupinthebottomhalfofthecoreexceedstheburnupinthetophalf.AhigherburnupwillresultinamorenegativeMTC.Amorebottomskewedaxialpowershapeallocates agreaterfluxweighting tothelowerregionofthecorewheretheburnupisgreater,therebyaccentuating theburnupeffectonMTC.TheMTCsensitivity toAFDisprovidedintheMTClimitreport.SincemeasuredAFDmustbedetermined every31days,thelatestmeasurement canbecomparedwiththeprediction andthedifference obtained.

Thisdifference isthenusedwiththeAFDsensitivity toobtainthecorrection.

Predictive Correction TermToaccountfortheMTCpredictive capability ofthedesignmodelforagivencycle,anadditional correction willbeappliedtothepredicted MTCtodetermine thefinalMTCtobecomparedtothesurveillance limit.Thepredictive correction willbedefinedas0pcm/'Forthedifference betweenthemeasuredandpredicted BOChotzeropowerMTC,whichever ismorenegative.

Theconditional exemption fromthemeasurement willbedetermined onacycle-specific basis.Thecoremodelperformance mustbebenchmarked totheoperating corebeforeapplyingtheprocedure fordetermining therevisedprediction.

Thespecificparameters chosenandtheassociated criteriaaregiveninReference 1.Meetingthesecriteriademonstrates thecoremodel'scapability toaccurately predictchangesinthecorecharacteristics withdepletion, andtherefore provideanaccurateprediction oftheHFP300ppmMTC~SafetyAnalysisConsiderations Thesafetyanalysisassumption ofaconstantMDC,andtheactualvalueassumed,willnotchange.Therefore, aconditional exemption fromthe300ppmMTCmeasurement basedonthemargintothesurveillance limitwillnothaveanadverseimpactonthesafeoperation oftheplant.

ATTACHMENT 1toAEP:NRC:1028A Page5Technical Specification ImpactsTheproposedT/Ssurveillance 4.1.1.4andconcomitant COLRchangesrequiredtosupporttheconditional exemption aredescribed inReference 1.TheseT/SchangeswillnotchangetheLCOorsurveillance requirement MTClimits.Thespecificvaluesofthesurveillance requirement andLCOMTCsremainunchanged bytheconditional exemption methodology documented inReference 1.Anadditional T/Swillbeadded(6.9.1.12) whichwilldefinethe"MostNegativeModerator Temperature Coefficient LimitReport."Thiscycle-specific reportwillprovidetheinformation requiredforcalculating themargintothesurveillance limit.Reference "e"willalsobeaddedtothelistofreferences inT/S6.9.1.11.2.

DETERMINATION OFNOSIGNIFICANT HAZARDSDoestheEOLMTCmeasurement conditional exemption involveasignificant increaseintheprobability orconsequences ofanaccidentpreviously evaluated'P NO.Theconditional exemption ofthemostnegativeMTCmeasurement doesnotchangethemostnegativeMTCsurveillance andLCOlimitsintheT/Ss.SincetheseMTCvaluesareunchanged, andsincethebasisforthederivation ofthesevaluesfromthesafetyanalysisMDCisunchanged, theconstantMDCassumedfortheFSARsafetyanalyseswillalsoremainunchanged.

Therefore, nochangeinthemodeling(i.e.,probabilities) oftheaccidentanalysisconditions orresponseisnecessary inordertoimplement thechangetotheconditional exemption methodology.

Inaddition, sincetheconstantMDCassumedinthesafetyanalysesisnotchangedbytheconditional exemption ofthemostnegativeMTCsurveillance measurement, theconsequences ofanaccidentpreviously evaluated intheFSARarenotincreased.

Thedosepredictions presented intheFSARforaSGTRremainvalidsuchthatmoresevereconsequences willnotoccur.Additionally, sincemassandenergyreleasesforLOCAandsteamline breakarenotincreased asaresultoftheunchanged MDC,thedosepredictions fortheseeventspresented intheFSARalsoremainbounding.

Criterion 2DoestheEOLMTCmeasurement conditional exemption createthepossibility ofanewordifferent kindofaccidentfromanyaccidentpreviously evaluated'O.

SincetheEOLMTCisnotchangedbytheconditional exemption methodology ofReference 1,thepossibility ofanaccidentwhichisdifferent thananyalreadyevaluated intheFSARhasnotbeencreated.Nonewordifferent failuremodeshavebeendefinedforanysystemorcomponent norhasanynewlimitingsinglefailurebeen ATTACHMENT 1toAEP:NRC:1028A Page6identified.Conservative assumptions forMDChavealreadybeenmodeledintheFSARanalyses.

Theseassumptions willremainvalidsincetheconditional exemption methodology documented inReference 1doesnotchangethesafetyanalysisMDCnortheT/SvaluesoftheMTC.Criterion 3DoestheEOLMTCmeasurement conditional exemption involveasignificant reduction inamarginofsafety'O.

Theevaluation oftheconditional exemption methodology documented inReference 1hastakenintoaccounttheapplicable CookNuclearPlantUnits1and2T/Ssandhasboundedtheconditions underwhichthespecifications permitoperation.

Theapplicable T/Ssaresurveillance 4.1.1.4,andreference "e"isaddedtothelistofreferences inSpecification 6.9.1.11.2.

Anadditional specification 6.9.1.12isaddedtodefinetherequirements forthe"MostNegativeModerator Temperature Coefficient LimitReport,"whichisdescribed inAppendices A,C,andDofReference 1.TheCOLRhasalsobeenmodifiedasdescribed inAppendixBofReference 1,TheanalyseswhichsupporttheseT/Sshavebeenevaluated.

Theresults,aspresented intheFSAR,remainboundingsincetheMDCassumedinthesafetyanalysesandtheLCOandsurveillance requirement MTCsintheT/Ssremainunchanged.

Therefore, themarginofsafety,asdefinedinthebasestotheseT/Ss,isnotreduced.Conclusion Itisconcluded thatoperation ofCookNuclearPlantUnits1and2withaconditional exemption fromthemostnegativeMTCmeasurement, asdescribed inReference 1andthisevaluation, doesnotinvolveanysignificant hazardsasdefinedin10CFR50.92.References 1.WCAP-13749-P, "SafetyEvaluation Supporting TheConditional Exemption oftheMostNegativeEOLModerator Temperature Coefficient Measurement,"

May1993.2,LetterET-NRC-93-3894, fromNicholasJ.Liparulo, ManagerNuclearSafetyandRegulatory Activities ofWestinghouse ElectricCorporation toR.C.Jones,ReactorSystemsBranchChief,DivisionofEngineering andSystemTechnology ofUSNRC,datedJune1,1993.

ATTACHMENT 2TOAEP:NRC:1028A EXISTINGTECHNICAL SPECIFICATION PAGESMARKEDTOREFLECTPROPOSEDCHANGES

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