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{{#Wiki_filter:DESIGNFEATURES5.2.1.2SHIELDBUILDINGa.Minimumannularspace=4feet.b.Annulusnominalvolume=543,000cubicfeet.C.Nominaloutsideheight(measuredfromtopoffoundationbasetothetopofthedome)=230.5feet.d.Nominalinsidediameter=148feet.e.Cylinderwallminimumthickness=3feet.f.Domeminimumthickness=2.5feet.g.Domeinsideradius=112feet.DESIGNPRESSUREANOTEMPERATUREI5.2.2Thecontainmentvesselisdesignedandshallbemaintainedforamaximuminternalpressureof44psigandatemperatureof264'F.PENETRATIONS5.2.3PenetrationsthroughthecontainmentstructurearedesignedandshallbemaintainedinaccordancewiththeoriginaldesignprovisionscontainedinSections3.8.2.1.10and6.2.4oftheFSARwithallo'wancefornormaldegrada-tionpursuanttotheapplileSurveillanceReuirements.53REACTORCOREg+'Z/rreyg@or~+gg~y~~oc/geeagp/jrpqg+Jy~~+ppg~FUELASSEMBLIES4Pf~~~+~PM~41PPc/~~J-/goalcz~+ZPPypQ~gg~r,~~5.3.1Thereacorcoreshallcona>n~ue1~3~mbreswseachfuelassemblycontainingamaximumof176fuelrodscladwithZircaloy-4.Eachfuelrodsha(haveanominalactivefuellengthofbetween134.1and136.7~414kfuelasseppbliesshallcontainfuelrodsofthesamenominalactivefuellength..~Theinitialcoreloadingshallhaveamaximumenrichmentof2.83weightpercentU-235.Reloadfuelshallbesimilarinphysicaldesigntotheinitialcoreloading.5.3.2ExceptforspecialtestasauthorizedbytheNRC,allfuelassembliesundercontrolelementassembliesshallbesleevedwithasleevedesignpreviouslyapprovedbytheNRC.ST;.LUCIE-UNIT.15-4AmendmentNo.3g,M,769203180i439203i3PDR*DOCK05000335PPDR I
{{#Wiki_filter:DESIGNFEATURES5.2.1.2SHIELDBUILDINGa.Minimumannularspace=4feet.b.Annulusnominalvolume=543,000cubicfeet.C.Nominaloutsideheight(measured fromtopoffoundation basetothetopofthedome)=230.5feet.d.Nominalinsidediameter=148feet.e.Cylinderwallminimumthickness
St.LucieUnit1DocketNo.50-335ProposedLicenseAmendmentAlternativeReuirementsforFuelAssembliesATTACHMENT2SAFETYANALYSISIntroductionThisproposedlicenseamendmentrevisestheSt.Lucie1TechnicalSpecificationsDesignFeaturesSection5.3.1topermittheuseoffuelassemblydesignsthatarenotlimitedtoamaximumuraniumweight.ReloadfuelassemblieswillbelimitedtothosedesignsthathavebeenanalyzedusinganNRCapprovedmethodologyandshownbytestsoranalysestocomplywithallapplicabledesignandsafetycriteria.ThefuelassemblydescriptionintheDesignFeaturesSectionoftheTechnicalSpecificationsprovidesadescriptionoftherequiredcharacteristicsofreloadfuel.TheSt.Lucie1TechnicalSpecificationDesignFeaturesSection5.3.1requiresthateachfuelrodinafuelassemblyshallcontainamaximumtotalweightof2250gramsuranium.However,theCycle11reloadwasdesigned,analyzedandfabricatedtocontainapproximately2275gramsofuraniumperfuelrod.ThepurposeofthisrequestistorevisethissectionoftheTechnicalSpecificationstopermittheuseoffuelassemblydesignsthatareofsimilarphysicaldesigntotheinitialcoreloading,butarenotlimitedbyanunnecessarymaximumfuelroduraniumweightrequirement.Therequirementofamaximumfuelroduraniumweightisunnecessarybecausechangestothecharacteristicsofthefuelrod(includinguraniumweight)thatcanimpactdesignandsafetycriteriaarespecificallyanalyzedduringthereloadevaluationprocess.Theseevaluations,usingNRCapprovedmethodology,assurethatapplicabledesignandsafetyanalysiscriteriaaremet.Additionally,complianceofthedesignwiththeLimitingSafetySystemSettingsandtheLimitingConditionsforOperationintheTechnicalSpecificationsisdemonstratedduringthereloadevaluationprocess.Therefore,theproposedamendmentwillnotadverselyimpactthesafeoperationofSt.LucieUnit1.TECHNICALDISCUSSIONChangestothecharacteristicsofthefuelrod/assemblythatcanimpactdesigncriteria,safetyanalysiscriteriaorsafetylimitsarespecificallyanalyzedforeachreload,usingNRCapprovedmethodology,toassurethatapplicablecriteriaorlimitsarenotviolated.Theseanalysesalsoassurethatplantoperationwiththe reloadfuelassembliescomplywiththeSafetyLimitsandLimitingConditionsForOperationintheTechnicalSpecifications.AnexampleofthisdesignprocessistheSt.LucieCycle11reloadwhereseveralchangestothefuelroddesignwereincorporatedintothereloadfuelassemblies.Thefuelroddesignchangesconsistedofthefollowing:1.Thepelletdiameterwasincreasedfrom0.370to0.377inches.2.Thepelletdensitywasincreasedfrom944to95%theoreticalUO,density.3.Thecladthicknesswasreducedfrom0.031to0.028inches(identicaltotheinitialcore).4.Thepellet-cladgapwasreducedfrom0.0080to0.0070inches.5.Theactivefuelheightwasincreasedfrom134.1to136.7inches(identicaltotheinitialcore).Thisisaccomplishedbyincreasingthetopnaturaluraniumaxialblanketfrom6.0to8.64inches.6.Theplenumspringlengthwasreducedfrom8.800to5.206inchestoaccommodatetheincreasedactivefuellength.7.Fuelrodheliumfillgaspressurewasincreasedfrom290to330psig.AlthoughthedesignoftheCycle11reloadfuelwassimilarinphysicalcharacteristicstothatofthefuelinitiallyloadedintothereactor,thechangesresultedinanincreasedfuelroduraniumweight(approximately14increaseinthefuelrodweight).Significantaspectsofthechangeswereevaluatedtoshowcompliancewithapplicabledesignandsafetycriteria.Othersecondaryaspectssuchas:structuralimpactonthereactorinternals,vesselsupportsandspentfuelpool,andspentfuelheatload,werequalitativelyevaluatedanddeemedtobeinsignificant.Thekeyresultsandconclusionsarediscussedbelow:a)Thereducedgapwidth,thedecreaseincladdingthickness,theincreaseinfueltheoreticaldensityandtheincreaseinfillgaspressurenecessitatedare-analysis/evaluationoftheLargeBreakandSmallBreakLOCAevents.Theresultsdemonstratedthatall10CFR50.46(b)criteriaweremet.b)TheincreaseintheheatedlengthofthefuelrodanditsimpactontheMinimumDeparturefromNucleateBoilingRatio(MDNBR)wasexplicitlyevaluatedintheThermalMargin/Low PressureandtheDNB/LCO(LimitingConditionForOperation)verificationanalysesforCycle11.TheresultsdemonstratedthatthecurrentsetpointsprovidesufficientmargintoDNB.c)TheimpactofthereductioningapwidthonthehotrodgapconductancethroughoutthecycleanditseffectonAnticipatedOperationalOccurrences(AOO)wasevaluated.EvaluationofthelimitingDNBAOO,LossofFlow,demonstratedthatthereferenceanalysisremainsboundingforCycle11.d)Theimpactofthedesignchangesonthecorephysicsparameterswereexplicitlymodeled.Theresultsdemonstratedthatthekeyparametersmetapplicabledesignandsafetycriteria,andTechnicalSpecifications.Forexample,peaklinearheatrateandradialpeakingfactorvaluesof13.4kw/ftand1.59,respectively,,werecalculated.ThecorrespondingTechnicalSpecificationlimitsare15.0and1.70.Excessshutdownmarginof1406pcmwascalculated.TheModeratorTemperatureCoefficientwascalculatedtobewithintheTechnicalSpecificationlimitsatalltimesduringCycle11operation.e)IntegrityofthenewfuelroddesignduringnormaloperationandAnticipatedOperationalOccurrenceswasconfirmedbyadetailedmechanicalperformanceanalysis.Itwasconcludedthat:themaximumsteady-statecladdingstrainwaswellbelowthe14designlimit,themaximumsteady-statecladdingstressesmettheASMEBoilerandPressureVesselCodeRequirements,thetransientcircumferentialstrainwaswithinthe1%designlimit,thetransientstresscalculatedduringpowerramps(uptothemaximumallowablepeakingfactor)waswithinthe56ksidesignlimit,claddingcreepcollapsewasprecluded,thefuelrodpressureremainedbelowthedesigncriteriaofsystempressureplus800psithroughoutlife,themaximumlocalcladdingoxidationwasbelowthe130micronlimit,thecladdingfatigueusagefactorwasbelowthe0.67designlimit, thefueltemperatureremainedbelowthemeltingtemperatureandthecladtotaluniformstrainremainsbelow14fortheAOOcondition.f)Radiologicalconsequencesforeachlimitingeventwereevaluatedagainst10CFR100criteriaandfoundtobeboundedbytheresultsofpreviousanalysis.Znconclusion,thedeletionofthemaximumrodweightintheDesignFeaturesSection5.3.1oftheTechnicalSpecificationsonFuelAssemblieswillpermitchangesinroduraniumweightwhilemaintainingsimilarityinphysicaldesigntothatoftheinitialcore.AnychangesinthecharacteristicsofthereloadfuelassemblieswillbelimitedtothosedesignsthathavebeenanalyzedusinganNRCapprovedmethodologyandshownbytestsoranalysestocomplywithallapplicabledesignandsafetycriteria.
=3feet.f.Domeminimumthickness
St.LucieUnit1DocketNo.50-335ProposedLicenseAmendmentAlternativeReuirementsforFuelAssembliesATTACHMENT3DETERMINATIONOFNOSIGNIFICANTHAZARDSCONSIDERATIONvThestandardsusedtoarriveatadeterminationthatarequestforamendmentinvolvesanosignificanthazardsconsiderationareincludedintheCommissionsregulation,10CFR50.92.10CFR50.92statesthatnosignificanthazardsconsiderationsareinvolvediftheoperationofthefacilityinaccordancewiththeproposedamendmentwouldnot(1)involveasignificantincreaseintheprobabilityorconsequencesofanaccidentpreviouslyevaluatedyor(2)createthepossibilityofanewordifferentkindofaccidentfromanyaccidentpreviouslyevaluated;or(3)involveasignificantreductioninamarginofsafety.Eachstandardisdiscussedasfollows:Operationofthefacilityinaccordancewiththeproposedamendmentwouldnotinvolveasignificantincreaseintheprobabilityorconsequencesofanaccidentpreviouslyevaluated.Theamendmentwillnotincreasetheprobabilityofanaccidentbecauseitdoesnotchangetheplantoperatingmodesortherequirementthatthereloadfuelbesimilarinphysicaldesigntotheinitialcoreloading.Thisrequirementensuresthatthefuelassemblyoutsidedimensionsandinterfacewithcoreinternalsandotherplantequipmentremainthesame.Thisresultsinnochangeinthehandlingandoperationofthefuelassembliesthatwouldincreasetheprobabilityofanaccident.Additionally,theconsequencesofanypreviouslyanalyzedaccidentwillnotbesignificantlyincreasedsinceanychangestothefuelassemblydesignwillcontinuetobeevaluatedusingNRCapprovedmethodologytodemonstratecompliancewithapplicabledesignandsafetycriteria.(2)Useofthemodifiedspecificationwouldnotcreatethepossibilityofanewordifferentkindofaccidentfromanypreviouslyevaluated.Theamendmentwillnotcreatethepossibilityofanewordifferentaccidentnotpreviouslyanalyzed,sincetheoperatingmodesandplantconfigurationwillnotbechangedfromthosepreviouslyanalyzedintheFinalSafetyAnalysisReport.
=2.5feet.g.Domeinsideradius=112feet.DESIGNPRESSUREANOTEMPERATURE I5.2.2Thecontainment vesselisdesignedandshallbemaintained foramaximuminternalpressureof44psigandatemperature of264'F.PENETRATIONS 5.2.3Penetrations throughthecontainment structure aredesignedandshallbemaintained inaccordance withtheoriginaldesignprovisions contained inSections3.8.2.1.10 and6.2.4oftheFSARwithallo'wance fornormaldegrada-tionpursuanttotheapplileSurveillance Reuirements.
I fL(3)Useofthemodifiedspecificationwouldnotinvolveasignificantreductioninamarginofsafety.Thisamendmentwillnotreducethemarginofsafetysincetheplantoperatingandsafetylimitswillremainunchanged.AllcycledesignshavebeenandwillcontinuetobeanalyzedusingNRCapprovedmethodstodemonstratethatexistingdesignlimitsandsafetyanalysiscriteriaaremetinadvanceofcycleoperation.Inaddition,theNRChasprovidedexamplesofamendmentsthatareconsiderednotlikelytoinvolvesignificanthazardsconsiderations(48Fed.Reg.at14870).Thisproposedamendmentmatchesexample(iii):"achangeresultingfromanuclearreactorcorereloading,ifnofuelassembliessignificantlydifferentfromthosefoundpreviouslyacceptabletotheNRCforapreviouscoreatthefacilityinquestionareinvolved.ThisassumesthatnosignificantchangesaremadetoacceptancecriteriafortheTechnicalSpecifications,thattheanalyticalmethodsusedtodemonstrateconformancewiththeTechnicalSpecificationsandregulationsarenotsignificantlychanged,andthattheNRChaspreviouslyfoundsuchmethodsacceptable."ThisparticularamendmentforalessrestrictivefuelroduraniumweightmatchesthisexamplesinceTechnicalSpecification5.3.1willcontinuetorequirereloadfuelassemblieswhicharesimilarinphysicaldesignasthatpreviouslyapprovedforSt.LucieUnit1~Whencomparedtothestandardssetin10CFR50.92(c),thisproposedamendmentdoesnotinvolveasignificantsafetyhazardsconsideration.ThisisfurtherverifiedbycomparingthischangewiththeexamplegivenintheFederalRegister,wherein,thisisachangethatwillresultinthereactorcorebeingreloadedwithfuelassemblydesignsthathavebeenanalyzedwithapplicableNRCapprovedmethodologytoverifycompliancewithapplicabledesignandsafetycriteria.Therefore,itisconcludedthatoperationofSt.LucieUnit1inaccordancewiththeproposedamendmentwillnotposeathreattothepublichealthandsafety.Basedontheabove,wehavedeterminedthattheproposedamendmentdoesnot(1)involveasignificantincreaseintheprobabilityorconsequencesofanaccidentpreviouslyevaluated,(2)createtheprobabilityofanewordifferentkindofaccidentfromanypreviouslyevaluated,or(3)involveasignificantreductioninamarginofsafety;andthereforedoesnotinvolveasignificanthazardsconsideration.
53REACTORCOREg+'Z/rreyg@or~+gg~y~~
oc/geeagp/jrpqg+Jy~~+ppg~FUELASSEMBLIES 4Pf~~~+~PM~41PPc/~~J-/goal cz~+ZPPyp Q~gg~r,~~5.3.1Thereacorcoreshallcona>n~ue1~3~mb reswseachfuelassemblycontaining amaximumof176fuelrodscladwithZircaloy-4.
Eachfuelrodsha(haveanominalactivefuellengthofbetween134.1and136.7~414kfuelasseppblies shallcontainfuelrodsofthesamenominalactivefuellength..~The initialcoreloadingshallhaveamaximumenrichment of2.83weightpercentU-235.Reloadfuelshallbesimilarinphysicaldesigntotheinitialcoreloading.5.3.2Exceptforspecialtestasauthorized bytheNRC,allfuelassemblies undercontrolelementassemblies shallbesleevedwithasleevedesignpreviously approvedbytheNRC.ST;.LUCIE-UNIT.15-4Amendment No.3g,M,769203180i43 9203i3PDR*DOCK05000335PPDR I
St.LucieUnit1DocketNo.50-335ProposedLicenseAmendment Alternative Reuirements forFuelAssemblies ATTACHMENT 2SAFETYANALYSISIntroduction Thisproposedlicenseamendment revisestheSt.Lucie1Technical Specifications DesignFeaturesSection5.3.1topermittheuseoffuelassemblydesignsthatarenotlimitedtoamaximumuraniumweight.Reloadfuelassemblies willbelimitedtothosedesignsthathavebeenanalyzedusinganNRCapprovedmethodology andshownbytestsoranalysestocomplywithallapplicable designandsafetycriteria.
Thefuelassemblydescription intheDesignFeaturesSectionoftheTechnical Specifications providesadescription oftherequiredcharacteristics ofreloadfuel.TheSt.Lucie1Technical Specification DesignFeaturesSection5.3.1requiresthateachfuelrodinafuelassemblyshallcontainamaximumtotalweightof2250gramsuranium.However,theCycle11reloadwasdesigned, analyzedandfabricated tocontainapproximately 2275gramsofuraniumperfuelrod.ThepurposeofthisrequestistorevisethissectionoftheTechnical Specifications topermittheuseoffuelassemblydesignsthatareofsimilarphysicaldesigntotheinitialcoreloading,butarenotlimitedbyanunnecessary maximumfuelroduraniumweightrequirement.
Therequirement ofamaximumfuelroduraniumweightisunnecessary becausechangestothecharacteristics ofthefuelrod(including uraniumweight)thatcanimpactdesignandsafetycriteriaarespecifically analyzedduringthereloadevaluation process.Theseevaluations, usingNRCapprovedmethodology, assurethatapplicable designandsafetyanalysiscriteriaaremet.Additionally, compliance ofthedesignwiththeLimitingSafetySystemSettingsandtheLimitingConditions forOperation intheTechnical Specifications isdemonstrated duringthereloadevaluation process.Therefore, theproposedamendment willnotadversely impactthesafeoperation ofSt.LucieUnit1.TECHNICAL DISCUSSION Changestothecharacteristics ofthefuelrod/assembly thatcanimpactdesigncriteria, safetyanalysiscriteriaorsafetylimitsarespecifically analyzedforeachreload,usingNRCapprovedmethodology, toassurethatapplicable criteriaorlimitsarenotviolated.
Theseanalysesalsoassurethatplantoperation withthe reloadfuelassemblies complywiththeSafetyLimitsandLimitingConditions ForOperation intheTechnical Specifications.
AnexampleofthisdesignprocessistheSt.LucieCycle11reloadwhereseveralchangestothefuelroddesignwereincorporated intothereloadfuelassemblies.
Thefuelroddesignchangesconsisted ofthefollowing:
1.Thepelletdiameterwasincreased from0.370to0.377inches.2.Thepelletdensitywasincreased from944to95%theoretical UO,density.3.Thecladthickness wasreducedfrom0.031to0.028inches(identical totheinitialcore).4.Thepellet-clad gapwasreducedfrom0.0080to0.0070inches.5.Theactivefuelheightwasincreased from134.1to136.7inches(identical totheinitialcore).Thisisaccomplished byincreasing thetopnaturaluraniumaxialblanketfrom6.0to8.64inches.6.Theplenumspringlengthwasreducedfrom8.800to5.206inchestoaccommodate theincreased activefuellength.7.Fuelrodheliumfillgaspressurewasincreased from290to330psig.AlthoughthedesignoftheCycle11reloadfuelwassimilarinphysicalcharacteristics tothatofthefuelinitially loadedintothereactor,thechangesresultedinanincreased fuelroduraniumweight(approximately 14increaseinthefuelrodweight).Significant aspectsofthechangeswereevaluated toshowcompliance withapplicable designandsafetycriteria.
Othersecondary aspectssuchas:structural impactonthereactorinternals, vesselsupportsandspentfuelpool,andspentfuelheatload,werequalitatively evaluated anddeemedtobeinsignificant.
Thekeyresultsandconclusions arediscussed below:a)Thereducedgapwidth,thedecreaseincladdingthickness, theincreaseinfueltheoretical densityandtheincreaseinfillgaspressurenecessitated are-analysis/evaluation oftheLargeBreakandSmallBreakLOCAevents.Theresultsdemonstrated thatall10CFR50.46(b)criteriaweremet.b)TheincreaseintheheatedlengthofthefuelrodanditsimpactontheMinimumDeparture fromNucleateBoilingRatio(MDNBR)wasexplicitly evaluated intheThermalMargin/Low PressureandtheDNB/LCO(Limiting Condition ForOperation) verification analysesforCycle11.Theresultsdemonstrated thatthecurrentsetpoints providesufficient margintoDNB.c)Theimpactofthereduction ingapwidthonthehotrodgapconductance throughout thecycleanditseffectonAnticipated Operational Occurrences (AOO)wasevaluated.
Evaluation ofthelimitingDNBAOO,LossofFlow,demonstrated thatthereference analysisremainsboundingforCycle11.d)Theimpactofthedesignchangesonthecorephysicsparameters wereexplicitly modeled.Theresultsdemonstrated thatthekeyparameters metapplicable designandsafetycriteria, andTechnical Specifications.
Forexample,peaklinearheatrateandradialpeakingfactorvaluesof13.4kw/ftand1.59,respectively,,
werecalculated.
Thecorresponding Technical Specification limitsare15.0and1.70.Excessshutdownmarginof1406pcmwascalculated.
TheModerator Temperature Coefficient wascalculated tobewithintheTechnical Specification limitsatalltimesduringCycle11operation.
e)Integrity ofthenewfuelroddesignduringnormaloperation andAnticipated Operational Occurrences wasconfirmed byadetailedmechanical performance analysis.
Itwasconcluded that:themaximumsteady-state claddingstrainwaswellbelowthe14designlimit,themaximumsteady-state claddingstressesmettheASMEBoilerandPressureVesselCodeRequirements, thetransient circumferential strainwaswithinthe1%designlimit,thetransient stresscalculated duringpowerramps(uptothemaximumallowable peakingfactor)waswithinthe56ksidesignlimit,claddingcreepcollapsewasprecluded, thefuelrodpressureremainedbelowthedesigncriteriaofsystempressureplus800psithroughout life,themaximumlocalcladdingoxidation wasbelowthe130micronlimit,thecladdingfatigueusagefactorwasbelowthe0.67designlimit, thefueltemperature remainedbelowthemeltingtemperature andthecladtotaluniformstrainremainsbelow14fortheAOOcondition.
f)Radiological consequences foreachlimitingeventwereevaluated against10CFR100criteriaandfoundtobeboundedbytheresultsofpreviousanalysis.
Znconclusion, thedeletionofthemaximumrodweightintheDesignFeaturesSection5.3.1oftheTechnical Specifications onFuelAssemblies willpermitchangesinroduraniumweightwhilemaintaining similarity inphysicaldesigntothatoftheinitialcore.Anychangesinthecharacteristics ofthereloadfuelassemblies willbelimitedtothosedesignsthathavebeenanalyzedusinganNRCapprovedmethodology andshownbytestsoranalysestocomplywithallapplicable designandsafetycriteria.
St.LucieUnit1DocketNo.50-335ProposedLicenseAmendment Alternative Reuirements forFuelAssemblies ATTACHMENT 3DETERMINATION OFNOSIGNIFICANT HAZARDSCONSIDERATION vThestandards usedtoarriveatadetermination thatarequestforamendment involvesanosignificant hazardsconsideration areincludedintheCommission sregulation, 10CFR50.92.10CFR50.92statesthatnosignificant hazardsconsiderations areinvolvediftheoperation ofthefacilityinaccordance withtheproposedamendment wouldnot(1)involveasignificant increaseintheprobability orconsequences ofanaccidentpreviously evaluatedy or(2)createthepossibility ofanewordifferent kindofaccidentfromanyaccidentpreviously evaluated; or(3)involveasignificant reduction inamarginofsafety.Eachstandardisdiscussed asfollows:Operation ofthefacilityinaccordance withtheproposedamendment wouldnotinvolveasignificant increaseintheprobability orconsequences ofanaccidentpreviously evaluated.
Theamendment willnotincreasetheprobability ofanaccidentbecauseitdoesnotchangetheplantoperating modesortherequirement thatthereloadfuelbesimilarinphysicaldesigntotheinitialcoreloading.Thisrequirement ensuresthatthefuelassemblyoutsidedimensions andinterface withcoreinternals andotherplantequipment remainthesame.Thisresultsinnochangeinthehandlingandoperation ofthefuelassemblies thatwouldincreasetheprobability ofanaccident.
Additionally, theconsequences ofanypreviously analyzedaccidentwillnotbesignificantly increased sinceanychangestothefuelassemblydesignwillcontinuetobeevaluated usingNRCapprovedmethodology todemonstrate compliance withapplicable designandsafetycriteria.
(2)Useofthemodifiedspecification wouldnotcreatethepossibility ofanewordifferent kindofaccidentfromanypreviously evaluated.
Theamendment willnotcreatethepossibility ofanewordifferent accidentnotpreviously
: analyzed, sincetheoperating modesandplantconfiguration willnotbechangedfromthosepreviously analyzedintheFinalSafetyAnalysisReport.
I fL(3)Useofthemodifiedspecification wouldnotinvolveasignificant reduction inamarginofsafety.Thisamendment willnotreducethemarginofsafetysincetheplantoperating andsafetylimitswillremainunchanged.
AllcycledesignshavebeenandwillcontinuetobeanalyzedusingNRCapprovedmethodstodemonstrate thatexistingdesignlimitsandsafetyanalysiscriteriaaremetinadvanceofcycleoperation.
Inaddition, theNRChasprovidedexamplesofamendments thatareconsidered notlikelytoinvolvesignificant hazardsconsiderations (48Fed.Reg.at14870).Thisproposedamendment matchesexample(iii):"achangeresulting fromanuclearreactorcorereloading, ifnofuelassemblies significantly different fromthosefoundpreviously acceptable totheNRCforapreviouscoreatthefacilityinquestionareinvolved.
Thisassumesthatnosignificant changesaremadetoacceptance criteriafortheTechnical Specifications, thattheanalytical methodsusedtodemonstrate conformance withtheTechnical Specifications andregulations arenotsignificantly changed,andthattheNRChaspreviously foundsuchmethodsacceptable."
Thisparticular amendment foralessrestrictive fuelroduraniumweightmatchesthisexamplesinceTechnical Specification 5.3.1willcontinuetorequirereloadfuelassemblies whicharesimilarinphysicaldesignasthatpreviously approvedforSt.LucieUnit1~Whencomparedtothestandards setin10CFR50.92(c),
thisproposedamendment doesnotinvolveasignificant safetyhazardsconsideration.
Thisisfurtherverifiedbycomparing thischangewiththeexamplegivenintheFederalRegister, wherein,thisisachangethatwillresultinthereactorcorebeingreloadedwithfuelassemblydesignsthathavebeenanalyzedwithapplicable NRCapprovedmethodology toverifycompliance withapplicable designandsafetycriteria.
Therefore, itisconcluded thatoperation ofSt.LucieUnit1inaccordance withtheproposedamendment willnotposeathreattothepublichealthandsafety.Basedontheabove,wehavedetermined thattheproposedamendment doesnot(1)involveasignificant increaseintheprobability orconsequences ofanaccidentpreviously evaluated, (2)createtheprobability ofanewordifferent kindofaccidentfromanypreviously evaluated, or(3)involveasignificant reduction inamarginofsafety;andtherefore doesnotinvolveasignificant hazardsconsideration.
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Revision as of 16:14, 29 June 2018

Proposed Tech Spec 5.3.1 Re Fuel Assemblies
ML17227A343
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Issue date: 03/13/1992
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ML17227A342 List:
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DESIGNFEATURES5.2.1.2SHIELDBUILDINGa.Minimumannularspace=4feet.b.Annulusnominalvolume=543,000cubicfeet.C.Nominaloutsideheight(measured fromtopoffoundation basetothetopofthedome)=230.5feet.d.Nominalinsidediameter=148feet.e.Cylinderwallminimumthickness

=3feet.f.Domeminimumthickness

=2.5feet.g.Domeinsideradius=112feet.DESIGNPRESSUREANOTEMPERATURE I5.2.2Thecontainment vesselisdesignedandshallbemaintained foramaximuminternalpressureof44psigandatemperature of264'F.PENETRATIONS 5.2.3Penetrations throughthecontainment structure aredesignedandshallbemaintained inaccordance withtheoriginaldesignprovisions contained inSections3.8.2.1.10 and6.2.4oftheFSARwithallo'wance fornormaldegrada-tionpursuanttotheapplileSurveillance Reuirements.

53REACTORCOREg+'Z/rreyg@or~+gg~y~~

oc/geeagp/jrpqg+Jy~~+ppg~FUELASSEMBLIES 4Pf~~~+~PM~41PPc/~~J-/goal cz~+ZPPyp Q~gg~r,~~5.3.1Thereacorcoreshallcona>n~ue1~3~mb reswseachfuelassemblycontaining amaximumof176fuelrodscladwithZircaloy-4.

Eachfuelrodsha(haveanominalactivefuellengthofbetween134.1and136.7~414kfuelasseppblies shallcontainfuelrodsofthesamenominalactivefuellength..~The initialcoreloadingshallhaveamaximumenrichment of2.83weightpercentU-235.Reloadfuelshallbesimilarinphysicaldesigntotheinitialcoreloading.5.3.2Exceptforspecialtestasauthorized bytheNRC,allfuelassemblies undercontrolelementassemblies shallbesleevedwithasleevedesignpreviously approvedbytheNRC.ST;.LUCIE-UNIT.15-4Amendment No.3g,M,769203180i43 9203i3PDR*DOCK05000335PPDR I

St.LucieUnit1DocketNo.50-335ProposedLicenseAmendment Alternative Reuirements forFuelAssemblies ATTACHMENT 2SAFETYANALYSISIntroduction Thisproposedlicenseamendment revisestheSt.Lucie1Technical Specifications DesignFeaturesSection5.3.1topermittheuseoffuelassemblydesignsthatarenotlimitedtoamaximumuraniumweight.Reloadfuelassemblies willbelimitedtothosedesignsthathavebeenanalyzedusinganNRCapprovedmethodology andshownbytestsoranalysestocomplywithallapplicable designandsafetycriteria.

Thefuelassemblydescription intheDesignFeaturesSectionoftheTechnical Specifications providesadescription oftherequiredcharacteristics ofreloadfuel.TheSt.Lucie1Technical Specification DesignFeaturesSection5.3.1requiresthateachfuelrodinafuelassemblyshallcontainamaximumtotalweightof2250gramsuranium.However,theCycle11reloadwasdesigned, analyzedandfabricated tocontainapproximately 2275gramsofuraniumperfuelrod.ThepurposeofthisrequestistorevisethissectionoftheTechnical Specifications topermittheuseoffuelassemblydesignsthatareofsimilarphysicaldesigntotheinitialcoreloading,butarenotlimitedbyanunnecessary maximumfuelroduraniumweightrequirement.

Therequirement ofamaximumfuelroduraniumweightisunnecessary becausechangestothecharacteristics ofthefuelrod(including uraniumweight)thatcanimpactdesignandsafetycriteriaarespecifically analyzedduringthereloadevaluation process.Theseevaluations, usingNRCapprovedmethodology, assurethatapplicable designandsafetyanalysiscriteriaaremet.Additionally, compliance ofthedesignwiththeLimitingSafetySystemSettingsandtheLimitingConditions forOperation intheTechnical Specifications isdemonstrated duringthereloadevaluation process.Therefore, theproposedamendment willnotadversely impactthesafeoperation ofSt.LucieUnit1.TECHNICAL DISCUSSION Changestothecharacteristics ofthefuelrod/assembly thatcanimpactdesigncriteria, safetyanalysiscriteriaorsafetylimitsarespecifically analyzedforeachreload,usingNRCapprovedmethodology, toassurethatapplicable criteriaorlimitsarenotviolated.

Theseanalysesalsoassurethatplantoperation withthe reloadfuelassemblies complywiththeSafetyLimitsandLimitingConditions ForOperation intheTechnical Specifications.

AnexampleofthisdesignprocessistheSt.LucieCycle11reloadwhereseveralchangestothefuelroddesignwereincorporated intothereloadfuelassemblies.

Thefuelroddesignchangesconsisted ofthefollowing:

1.Thepelletdiameterwasincreased from0.370to0.377inches.2.Thepelletdensitywasincreased from944to95%theoretical UO,density.3.Thecladthickness wasreducedfrom0.031to0.028inches(identical totheinitialcore).4.Thepellet-clad gapwasreducedfrom0.0080to0.0070inches.5.Theactivefuelheightwasincreased from134.1to136.7inches(identical totheinitialcore).Thisisaccomplished byincreasing thetopnaturaluraniumaxialblanketfrom6.0to8.64inches.6.Theplenumspringlengthwasreducedfrom8.800to5.206inchestoaccommodate theincreased activefuellength.7.Fuelrodheliumfillgaspressurewasincreased from290to330psig.AlthoughthedesignoftheCycle11reloadfuelwassimilarinphysicalcharacteristics tothatofthefuelinitially loadedintothereactor,thechangesresultedinanincreased fuelroduraniumweight(approximately 14increaseinthefuelrodweight).Significant aspectsofthechangeswereevaluated toshowcompliance withapplicable designandsafetycriteria.

Othersecondary aspectssuchas:structural impactonthereactorinternals, vesselsupportsandspentfuelpool,andspentfuelheatload,werequalitatively evaluated anddeemedtobeinsignificant.

Thekeyresultsandconclusions arediscussed below:a)Thereducedgapwidth,thedecreaseincladdingthickness, theincreaseinfueltheoretical densityandtheincreaseinfillgaspressurenecessitated are-analysis/evaluation oftheLargeBreakandSmallBreakLOCAevents.Theresultsdemonstrated thatall10CFR50.46(b)criteriaweremet.b)TheincreaseintheheatedlengthofthefuelrodanditsimpactontheMinimumDeparture fromNucleateBoilingRatio(MDNBR)wasexplicitly evaluated intheThermalMargin/Low PressureandtheDNB/LCO(Limiting Condition ForOperation) verification analysesforCycle11.Theresultsdemonstrated thatthecurrentsetpoints providesufficient margintoDNB.c)Theimpactofthereduction ingapwidthonthehotrodgapconductance throughout thecycleanditseffectonAnticipated Operational Occurrences (AOO)wasevaluated.

Evaluation ofthelimitingDNBAOO,LossofFlow,demonstrated thatthereference analysisremainsboundingforCycle11.d)Theimpactofthedesignchangesonthecorephysicsparameters wereexplicitly modeled.Theresultsdemonstrated thatthekeyparameters metapplicable designandsafetycriteria, andTechnical Specifications.

Forexample,peaklinearheatrateandradialpeakingfactorvaluesof13.4kw/ftand1.59,respectively,,

werecalculated.

Thecorresponding Technical Specification limitsare15.0and1.70.Excessshutdownmarginof1406pcmwascalculated.

TheModerator Temperature Coefficient wascalculated tobewithintheTechnical Specification limitsatalltimesduringCycle11operation.

e)Integrity ofthenewfuelroddesignduringnormaloperation andAnticipated Operational Occurrences wasconfirmed byadetailedmechanical performance analysis.

Itwasconcluded that:themaximumsteady-state claddingstrainwaswellbelowthe14designlimit,themaximumsteady-state claddingstressesmettheASMEBoilerandPressureVesselCodeRequirements, thetransient circumferential strainwaswithinthe1%designlimit,thetransient stresscalculated duringpowerramps(uptothemaximumallowable peakingfactor)waswithinthe56ksidesignlimit,claddingcreepcollapsewasprecluded, thefuelrodpressureremainedbelowthedesigncriteriaofsystempressureplus800psithroughout life,themaximumlocalcladdingoxidation wasbelowthe130micronlimit,thecladdingfatigueusagefactorwasbelowthe0.67designlimit, thefueltemperature remainedbelowthemeltingtemperature andthecladtotaluniformstrainremainsbelow14fortheAOOcondition.

f)Radiological consequences foreachlimitingeventwereevaluated against10CFR100criteriaandfoundtobeboundedbytheresultsofpreviousanalysis.

Znconclusion, thedeletionofthemaximumrodweightintheDesignFeaturesSection5.3.1oftheTechnical Specifications onFuelAssemblies willpermitchangesinroduraniumweightwhilemaintaining similarity inphysicaldesigntothatoftheinitialcore.Anychangesinthecharacteristics ofthereloadfuelassemblies willbelimitedtothosedesignsthathavebeenanalyzedusinganNRCapprovedmethodology andshownbytestsoranalysestocomplywithallapplicable designandsafetycriteria.

St.LucieUnit1DocketNo.50-335ProposedLicenseAmendment Alternative Reuirements forFuelAssemblies ATTACHMENT 3DETERMINATION OFNOSIGNIFICANT HAZARDSCONSIDERATION vThestandards usedtoarriveatadetermination thatarequestforamendment involvesanosignificant hazardsconsideration areincludedintheCommission sregulation, 10CFR50.92.10CFR50.92statesthatnosignificant hazardsconsiderations areinvolvediftheoperation ofthefacilityinaccordance withtheproposedamendment wouldnot(1)involveasignificant increaseintheprobability orconsequences ofanaccidentpreviously evaluatedy or(2)createthepossibility ofanewordifferent kindofaccidentfromanyaccidentpreviously evaluated; or(3)involveasignificant reduction inamarginofsafety.Eachstandardisdiscussed asfollows:Operation ofthefacilityinaccordance withtheproposedamendment wouldnotinvolveasignificant increaseintheprobability orconsequences ofanaccidentpreviously evaluated.

Theamendment willnotincreasetheprobability ofanaccidentbecauseitdoesnotchangetheplantoperating modesortherequirement thatthereloadfuelbesimilarinphysicaldesigntotheinitialcoreloading.Thisrequirement ensuresthatthefuelassemblyoutsidedimensions andinterface withcoreinternals andotherplantequipment remainthesame.Thisresultsinnochangeinthehandlingandoperation ofthefuelassemblies thatwouldincreasetheprobability ofanaccident.

Additionally, theconsequences ofanypreviously analyzedaccidentwillnotbesignificantly increased sinceanychangestothefuelassemblydesignwillcontinuetobeevaluated usingNRCapprovedmethodology todemonstrate compliance withapplicable designandsafetycriteria.

(2)Useofthemodifiedspecification wouldnotcreatethepossibility ofanewordifferent kindofaccidentfromanypreviously evaluated.

Theamendment willnotcreatethepossibility ofanewordifferent accidentnotpreviously

analyzed, sincetheoperating modesandplantconfiguration willnotbechangedfromthosepreviously analyzedintheFinalSafetyAnalysisReport.

I fL(3)Useofthemodifiedspecification wouldnotinvolveasignificant reduction inamarginofsafety.Thisamendment willnotreducethemarginofsafetysincetheplantoperating andsafetylimitswillremainunchanged.

AllcycledesignshavebeenandwillcontinuetobeanalyzedusingNRCapprovedmethodstodemonstrate thatexistingdesignlimitsandsafetyanalysiscriteriaaremetinadvanceofcycleoperation.

Inaddition, theNRChasprovidedexamplesofamendments thatareconsidered notlikelytoinvolvesignificant hazardsconsiderations (48Fed.Reg.at14870).Thisproposedamendment matchesexample(iii):"achangeresulting fromanuclearreactorcorereloading, ifnofuelassemblies significantly different fromthosefoundpreviously acceptable totheNRCforapreviouscoreatthefacilityinquestionareinvolved.

Thisassumesthatnosignificant changesaremadetoacceptance criteriafortheTechnical Specifications, thattheanalytical methodsusedtodemonstrate conformance withtheTechnical Specifications andregulations arenotsignificantly changed,andthattheNRChaspreviously foundsuchmethodsacceptable."

Thisparticular amendment foralessrestrictive fuelroduraniumweightmatchesthisexamplesinceTechnical Specification 5.3.1willcontinuetorequirereloadfuelassemblies whicharesimilarinphysicaldesignasthatpreviously approvedforSt.LucieUnit1~Whencomparedtothestandards setin10CFR50.92(c),

thisproposedamendment doesnotinvolveasignificant safetyhazardsconsideration.

Thisisfurtherverifiedbycomparing thischangewiththeexamplegivenintheFederalRegister, wherein,thisisachangethatwillresultinthereactorcorebeingreloadedwithfuelassemblydesignsthathavebeenanalyzedwithapplicable NRCapprovedmethodology toverifycompliance withapplicable designandsafetycriteria.

Therefore, itisconcluded thatoperation ofSt.LucieUnit1inaccordance withtheproposedamendment willnotposeathreattothepublichealthandsafety.Basedontheabove,wehavedetermined thattheproposedamendment doesnot(1)involveasignificant increaseintheprobability orconsequences ofanaccidentpreviously evaluated, (2)createtheprobability ofanewordifferent kindofaccidentfromanypreviously evaluated, or(3)involveasignificant reduction inamarginofsafety;andtherefore doesnotinvolveasignificant hazardsconsideration.

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