ML17309A545

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Forwards Application for Amend to License DPR-18,increasing Allowable RCA to Improved TS Values (NUREG-1431). Westinghouse Proprietary Rept WCAP-11668 & Nonproprietary Rept WCAP-11678 Encl.Proprietary Rept WCAP-11668 Withheld
ML17309A545
Person / Time
Site: Ginna Constellation icon.png
Issue date: 05/23/1994
From: MECREDY R C
ROCHESTER GAS & ELECTRIC CORP.
To: JOHNSON A R
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM), Office of Nuclear Reactor Regulation
Shared Package
ML17263A656 List:
References
RTR-NUREG-1431 NUDOCS 9405310164
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..ACCELERATEDDISTRIBUTIONDEMONS+ATIONSYSTEMJIREGULATORYINFORMATIONDISTRIBUTIONSYSTEM(RIDS)ACCESSIONNBR:9405310164DOC.DATE:94/05/23NOTARIZED:YESDOCKETFACIL:50-244RobertEmmetGinnaNuclearPlant,Unit1,RochesterG05000244AUTH.*NAMEAUTHORAFFILIATIONMECREDY,R.C.RochesterGas6ElectricCorp.RECIP.NAMERECIPIENTAFFILIATIONJOHNSON,A.R.ProjectDirectorateI-3+5R

SUBJECT:

ForwardsapplicationforamendtolicenseDPR-18,increasingallowableRCAtoimprovedTSvalues(NUREG-1431).IWestinghouseproprietaryreptWCAP-116686nonproprietaryreptWCAP-11678encl.ProprietaryreptWCAP-11668withheld.DDISTRIBUTIONCODE:AP01DCOPIESRECEIVED:LTRJENCLLSIZE:/STITLE:ProprietaryReviewDistribution-PreOperatingLicense6OperatingR/NOTES:LicenseExpdateinaccordancewith10CFR2,2.109(9/19/72).05000244ARECIPIENTIDCODE/NAMEPD1-3LAJOHNSON,ACOPIESLTTRENCL1133RECIPIENTIDCODE/NAMEPD1-3PDCOPIESLTTRENCL11DDINTERNAL:AEO~DOA~GFfQEEXTERNALNRCPDR01111110OGC/HDS110DSNOTETOALL"RIDS"RECIPIENTS:DDPLEASEHELPUSTOREDUCEWASTE!CONTACTTHEDOCUMENTCONTROLDESK,ROOMP1-37(EXT.20079)TOELIMINATEYOURNAMEFROMDISTRIBUTIONLISTSFORDOCUMENTSYOUDON'TNEED!TOTALNUMBEROFCOPIESREQUIRED:LTTR9ENCL7 Itg~0<~

/////I///////'g//Z1//I///I/I///////////i////I//////SKfROCHESTERGASANDELECTRICCORPORATIONo89EASTAVENUE,ROCHESTERN.Y.14649-0001ROBERTC.MECREDYVicePresidentClnnaNuclearProductionMay23,1994TELEPHONEhREACODE7tB5462700U.S.NuclearRegulatoryCommissionDocumentControlDeskAttn:AllenR.JohnsonProjectDirectorateI-3Washington,D.C.20555

Subject:

ApplicationforAmendmenttoOperatingLicenseReactorCoolantActivityTechnicalSpecificationsRochesterGasandElectricCorporationR.E.GinnaNuclearPowerPlantDocketNo.50-244Ref.(a):NRCLetter,C.RossitoA.Ladieu(WOG),"AcceptanceforReferencingofLicensingTopicalReportWCAP-10698...",March30,1987.(b):NUREG-0916,"SafetyEvaluationReportRelatedtotheRestartofR.E.GinnaNuclearPowerPlant",May1982.(c):RG&ELetter,R.MecredytoA.Johnson(NRC),"EmergencyResponseCapability...",October14,1992.(d):NRCLetter,A.JohnsontoR.Mecredy(RG&E),EmergencyResponseCapability-ConformancetoRegulatoryGuide1.97,revision3",February24,1993.(e):WOGLetter,L.WalshandA.EngeltoR.Jones(NRC),"WestinghouseOwnersGroupSteamGeneratorTubeUncoveryIssue",March31,1992.(f):NRCLetter,R.JonestoL.Walsh(WOG),"WestinghouseOwnersGroup,SteamGeneratorTubeUncoveryIssue",March10,1993.

DearMr.Johnson:

WCAP-11668(Proprietary)/WCAP-11678(Non-Proprietary)evaluatethepotentialradiologicalconsequencesduetoasteamgeneratortuberupture(SGTR)fortheR.E.GinnaNuclearPowerPlant.Thisg'Ti4053101b4'Tl40523PDR"ADOt"K'05000244ThepurposeofthisapplicationforAmendmenttoOperatingLicenseistoamendAppendixAofthatLicensetoincreasetheTechnicalSpecificationallowableprimarycoolantiodine(I-131)activitylimitfrom0.2pC+igmto1.0pCi/gm;andthetotalprimarycoolantactivityfrom84/EpCi/gmtotheStandardTechnicalSpecificationvalueof100/EpCi/gm,consistentwiththeImprovedTechnicalSpecifications(NUREG-1431).

evaluationutilizestheanalysismethodologyofWCAP-10698-P-A"SGTRAnalysisMethodologytoDeterminetheMargintoSteamGeneratorOverfill."RG&EhasmettherequirementsforusageofWCAP-10698asoutlinedinNuclearRegulatoryCommissionletterfromC.E.Rossi(NRC)toA.E.Ladieu(WOG),(Referencea).Theletterrequiredeachutilitytoprovidefiveplantspecificinputs:1.Demonstrationthatcriticaloperatoractiontimesusedintheanalysisarerealisticandconsistentwiththoseobservedduringsimulatorexercises.2.AsitespecificSteamGeneratorTubeRuptureradiologicaloffsiteconsequenceanalysis.3.Astructural,analysisofthemainsteam'inesdemonstratingadequacyunderwater-filledconditions.4.Alistofsystems,components,andinstrumentationcreditedforaccidentmitigationandthespecifiedsafetygradeforeach.5.Acomparisonoftheplanttothe"boundingplant"usedinWCAP-10698.Items2and5areaddressedin.thesitespecificanalysisbeingsubmittedwiththisletter,WCAP-11668(Proprietary).Item3wasaddressedduringthereviewoftheSteamGeneratorTubeRuptureincidentatGinnaStation.ItsacceptabilityisdocumentedinNUREG-0916,(Referenceb).Item4iscontainedinourpost-accidentinstrumentationsubmittal(Referencec)(re.RegulatoryGuide1.97).NRCreviewandacceptanceofthisinformationisdocumentedinreferenced.Item1isdiscussedbelow.DuringtheweekofAugust19through23,1991simulatorrunsofthetwomostlimitingcasesidentifiedinWCAP-11668(Proprietary)/WCAP-11678(Non-Proprietary),weremadetovalidateassumedoperatorresponsetimes.ThesesimulatorrunsdemonstratedthatnotonlyweretheoperatorresponsetimesassumedintheWCAPsconservativewithadequatemargin,butalsothatrecentrefinementsintheemergencyoperatingprocedureshavefurtherreducedthelikelihoodofoverfillingtherupturedsteamgenerator.Forthetwolimitingcasesidentifiedoperatorresponsepreventedoverfillwithsignificantmargin,andterminatedbreakflowinunder45minutes.InbothcasesitwasnecessarytousetheWCAPassumedtimesforoperatoractionoutsidethecontrolroom.Thesetimeswerethelimitingfactorsinthescenarios,ascontrolroomoperatorshadtowaittoproceedwithfurthermitigatingactionsuntiltheseactionswereassumedtobecompleted.Operatorcritiquefollowingthesessionsindicatedthattheyfeltthesetimeswereunrealisticallyconservative.We,therefore,feelthatactualmitigationtimeswouldbeevenlessthanthosedemonstratedduringthesimulatorexercise.WCAP-11668/11678assumesthetuberuptureremainscoveredthrough-ItI outtheevent.Morerecentlyithasbeensuggestedthat,thisassumptionmaynotbeconservative.TheWestinghouseOwnersGroup(WOG)hasundertakenaprogramtoassesstheconsequencesoftuberuptureuncovery.Theresultsindicatethattheincreaseindosesisinsignificant.Theseresultsweretransmittedtothestaff(Referencee).Thestaffhasreviewedandapprovedthistransmittal(referencef).Therefore,wefeelthisissuehasbeenadequatelyaddressed.ItshouldbenotedthataproposaltomodifySection3.1.4.3.ahasalreadybeensubmittedtotheNRCvialetterMay13,1994.Page3.1-21ofAttachmentsBandCisbeingsubmittedinbothversions,sothatapprovalisnotdependentonthesequenceofproposedLicenseAmendmentRequestreviews.WerequestthatuponNRCapproval,thisamendmentshouldbeconsideredeffectiveimmediatelyandimplementedwithin60days.Veryrulyyours,oertc.ecryBJF/190Attachment

Enclosures:

1~One(1)submittalofanApplicationforAmendmenttoOperatingLicenseandassociatedsafetyevaluation.2~3~4~One(1)copyofanApplicationforWithholding,CAW-87-123,datedDecember3,1987,accompanyingAffidavit,andProprietaryInformationNoticeOne(1)copyofWCAP-11668,"LOFTTR2AnalysisofPotentialRadiologicalConsequencesFollowingaSteamGeneratorTubeRuptureattheR.E.GinnaNuclearPlant",November1987(Proprietary).One(1)copyofWCAP-11678,"LOFTTR2AnalysisofPotentialRadiologicalConsequencesFollowingaSteamGeneratorTubeRuptureat,theR.E.GinnaNuclearPlant",November1987(Non-Proprietary).xc>>Mr.AllenR.Johnson(MailStop14Dl)ProjectDirectorateI-3Washington,D.C.20555U.S.NuclearRegulatoryCommissionRegionI475AllendaleRoadKingofPrussia,PA19406GinnaSeniorResidentInspector WESTINGHOUSEPROPRIETARYCLASS2WCAP"1166874>5'9QVLOFTTR2ANALYSISOFPOTENTIALRADIOLOGICALCONSEQUENCESFOLLOWINGASTEAMGENERATORTUBERUPTUREATTHER.E.GINNANUCLEARPOWERPLANT0.J.MendlerK.RubinNOVEMBER1987NuclearSafetyDepartmentThisdocumentcontainsinformationproprietarytoWestinghouseElectricCorporation;itissubmittedin.confidenceandistobeusedsolelyforthepurposeforwhichitisfurnishedandreturneduponrequest.Thisdocumentandsuchinformationisnottobereproduced,transmitted,disclosedorusedotherwiseinwholeorinpartwithoutauthorizationofWestinghouseElectricCorporation,NuclearEnergySystems.WestinghouseElectricCorporationNuclearEnergySystemsP.O.Box355Pittsburgh,Pennsylvania152301987byWestinghouseElectricCorporation1074v:1OP/120487 IP.'\10 WESTINGHOUSEPROPRIETARYCLASS2ThisdocumentcontainsmaterialthatisproprietarytotheWestinghouseElectricCorporation.Thispropr'ietaryinformationhasbeenmarkedbymeansofbrackets.ThebasisformarkingthematerialproprietaryisidentifiedbymarginalnotesreferringtothestandardsinSection8oftheaffidavitofR.A.Wiesemannofrecord"IntheHatterofAcceptanceCriteriaforEmergency.CoreCoolingSystemsforLightWaterCooledNuclearPowerReactors(DocketNo.RH-50-1)"atteanscriptpages3706through3710(February24,1972).'DuetotheproprietarynatureofthematerialcontainedinthisreportwhichwasobtainedatconsiderableWestinghouseexpenseandthereleaseofwhichwouldseriouslyaffectourcompetitiveposition,werequestthisinformationtobewithheldfrompublicdisclosureinaccordancewiththeRulesofPractice,10CFR2.790,andthattheinformationpresentedthereinbesafeguardedinaccordancewith10CFR2.903.Webelievethatwithholdingthisinformationwillnotadverselyaffectthepublicinterest.ThisinformationisforyourinternaluseonlyandshouldnotbereleasedtopersonsororganizationsoutsidethedirectorateofRegulationandtheACRSwithoutpriorapprovalofWestinghouseElectricCorporation.Shoulditbecome1necessarytoreleasethisinformationtosuchpersonsaspartofthereviewprocedure,pleasecontactWestinghouseElectricCorporationandtheywillmakethenecessaryarrangementsrequiredtoprotecttheirproprietary'nterests.1D74v:1D/7120B7 WESTINGHOUSEPROPRIETARYCLASS2TABLEOFCONTENTSPacaesI.INTRODUCTIONII.THERHALHYDRAULICANALYSISA.B.C.D.E.F.DesignBasisAccidentConservativeAssumptionsOperatorActionTimesTransientDescription-Case1TransientDescription-Case2HassReleases236132434III.RADIOLOGICALCONSEQUENCESANALYSISIV.CONCLUSION4358V.REFERENCES591074v:1D/112087 00-WESTINGHOUSEPROPRIETARYCLASS2I.INTRODUCTIONAnevaluationofthepotentialradiologicalconsequencesduetoasteamgeneratortuberupture(SGTR)eventhasbeenperformedfortheR.E.GinnanuclearpowerplanttodemonstratethattheoffsiteradiationdoseswillbelessthantheallowableguidelinesbasedontheStandardTechnicalSpecificationlimitonprimarycoolantactivity.Theevaluationdiscussedhereinassumesthat151.ofthesteamgeneratortubesareplugged.AdesignbasissteamgeneratortuberupturewasanalyzedforGinnausingthemethodologydevelopedinMCAP-10698(reference1)andthesupplementtoHCAP-10698(reference2).TwosinglefailurecaseswereconsideredtodeterminewhichisthemostlimitingsinglefailureforGinnawithrespecttoradiological.consequences.Thetwocasesexaminedwere:a,cCase1Intactsteamgeneratorpoweroperatedreliefvalve(PORV)failsclosedandmustbelocallyopened.Case2Rupturedsteamgeneratorpoweroperatedreliefvalvefailsopenandmustbelocallyisolated.PlantresponsetotheeventwasmodeledusingtheLOFTTR2computercodewithconservativeassumptionsofbreaksizeandlocation,condenseravailabilityandinitialsecondarywatermassinthefaultedsteamgenerator.Theanalysismethodologyincludesthesimulationoftheoperatoractionsforrecoveryfrom'steamgeneratortuberupturebasedontheWestinghouseOwnersGroupEmergencyResponseGuidelines,whicharethebasisfortheGinnaEmergencyOperatingProcedures.ThemassreleaseswerecalculatedwiththeLOFTTR2~programfromtheinitiationoftheeventuntilterminationofthebreakflow.Forthetimeperiodfollowingbreakflowtermination,steamreleasesandfeedwaterflowsfromtheintactandfaultedsteamgeneratorsweredeterminedfromamassandenergybalanceusingthecalculatedRCSandsteamgeneratorconditionsatthetimeofleakagetermination.Themassreleasesforbothcaseswereusedtodeterminetheradiationdosesattheexclusionareaboundaryandlowpopulationzoneassumingthattheprimarycoolantactivity'isattheStandardTechnicalSpecificationlimitpriortotheaccident.1074v:1D/112087 MESTINGHOUSEPROPRIETARYCLASS2II.THERMALHYDRAULICANALYSISIntegratedmassreleasestotheatmosphereandcondenserduringasteamgeneratortuberuptureeventwerecalculatedforvarioustimeperiodsduringtheaccident.ThissectionincludesthemethodsandassumptionsusedtomodeltheSGTReventandcalculatethemassreleases,aswellasthesequenceofeventsfortherecovery.A.DesinBasisAccidentTheaccidentmodeledisthecompleteseveranceofasteamgeneratortubelocatedatthetubesheetonthecoldlegside.Itwasalsoassumedthatlossofoffsitepoweroccurredatthetimeofreactortrip,andtheworstrodwasassumedtobestuckatreactortrip.a,cThemostlimitingsinglefailurewithrespecttosteamgeneratoroverfillwasdeterminedbyreference1tobeafailedclosedPORVontheintactsteamgenerator.SinceGinnaisatwoloopplant,theintactsteamgeneratorPORVmustbelocallyopenedbeforeRCScooldowncanbegin.ThisadditionaltimetolocallyopentheintactsteamgeneratorPORVwilldelayRCSdepressurization,causinganincreaseintotalprimarytosecondaryleakage.Consequently,morewaterwillaccumulateinthefaultedsteamgenerator.ThecasewheretheintactsteamgeneratorPORVfailstoopenondemandandmustbelocallyopenedwillbereferredtoasCase1.Themostlimitingsinglefailurewithrespecttooffsitedoseswasdeterminedbyreference2tobeafailedopenPORVonthefaulte'dsteamgenerator.FailureofthisPORVwillcauseanuncontrolleddepressurizationofthefaultedsteamgeneratorwhichwillincreaseprimarytosecondaryleakage.PressureintherupturedsteamgeneratorwillremainbelowthatintheprimarysystemuntilthefailedPORVcanbeisolated,andrecoveryactionscompleted.Thecasewherethefaulted'teamgeneratorPORVfailsopenandmustbelocallyisolatedwillbereferredtoasCase2.1074v:1D/112087 WESTINGHOUSEPROPRIETARYCLASS2B.ConservativeAssumtionsPlantresponsesandmassreleasesfromtheintactandfaultedsteamgeneratorpriortobreakflowterminationwerecalculatedusingLOFTTR2.WhilemodelingtheSGTReventthefollowingassumptionsweremade:1.ReactorTrionOvertemeratureDelta-Ta,cAturbinerunbackcanbeinitiatedautomaticallyortheoperatorcanmanuallyreducetheturbineloadtoattempttopreventareactortriponovertemperaturedelta-T.Althoughturbinerunbackissimulatedinthisanalysis,creditis.nottakenfordelayingreactortrip.Reactortripisassumedtooccuronovertemperaturedelta-T.Duetotheassumedlossofoffsitepowerthecondenserisnotavailableforsteamreleasesoncethereactoristripped.Consequently,afterreactortripthesteamgeneratorPORYsareusedforsteamreleases.Thusanearliertriptimeleadstomoresteamreleasedtotheatmospherefromthefaultedandintactsteamgenerators.2.PoweraTheinitialsteamgeneratorwatermassdecreaseswithincreasingpowerlevel.,Thus,alowerinitialpowerresultsinahigherinitialsteamgeneratorsecondarywatermasswhichisconservative.Onthisbasis,100%nominalpowerwasassumedfortheanalysisratherthanconsideringanoverpowerfactor.3.PressurizerWaterLevelTheRCSdepressurizationrateincreasesafterthepressurizerempties.Ahigherpressurizerwaterlevelwillincreasethetimerequiredforthepressurizertoempty.Thisresultsinmaintainingahigherprimarytosecondarypressuredifferentialandthusalargerbreakflowrateforalongertimeperiod.Therefore,itisconcludedthatmaximizingthepressurizerwaterlevelisconservative.a,c1074v:1D/112087 HESTINGHOUSEPROPRIETARYCLASS24.SteamGeneratorSeoond~arMassAhigherinitialsecondarywatermassintherupturedsteamgeneratorwasdeterminedbyReference1tobeconservativeforoverfill.FortheCase1analysisturbinerunbackwasassumedinitiatedandwassimulatedbyartificiallyincreasinginitialsteamgeneratorwatermass.TheinitialsteamgeneratortotalfluidmasswasassumedtobelOAabovenominalvalueplusthedifferentialmassbetween100%powerand70Ãpowertosimulateturbinerunback.However,ifsteamgeneratoroverfilldoesnotoccur,alowerinitialmassintheruptur'edsteamgeneratorresultsinaconservativepredictionofoffsitedoses..Thus,forCase2theinitialsecondarymasswasassumedtocorrespondtooperationat10Kbelownominalsteamgeneratorwatermass.a,c5.BreakLocationThetuberuptureanalyzedisadouble-endedbreakofonesteamgeneratortubelocatedatthetopofthetubesheetontheoutletsideofthesteamgenerator.Thelocationofthebreakonthecoldsideofthesteamgeneratorresultsinhigherprimarytosecondaryleakagethanabreakonthehotsideofthesteamgeneratorasdeterminedbyreference1.Therefore,itisconcludedthatthecoldlegsidebreaklocationisconservative.4i,C6.ReactorTriOelaAsnotedpreviously,theresultsforcaseswhichproduceanearlierreactortriparemoreconservativewithrespecttotheradiologicalconsequencesfromaSGTR.Thus,aminimumdelaytimefromthereactortripsignaltoreactortripisconservativefortheanalysis.Inaddition,asnotedabove,nocreditistakenforturbinerunbackdelayingreactortrip.a,c.1074v:10/112387 ttESTINGHOUSEPROPRIETARYCLASS27.T~tiTiD1Followingareactortrip,theturbinewillbeautomaticallytrippedafterasuitabledelaytime.Minimizingthedelaytimebetweenreactortripandturbinetripreducestheamountofsteamflowtotheturbineandincreasesthe.secondarywaterinventory.Thus,aminimumdelaytimebetweenreactortripandturbinetripisconservativefortheSGTRanalysis.a,c8.SteamGeneratorReliefValvePressureSetointHithalossofoffsitepower,thesecondarypressurewillincreasefollowingreactorandturbinetrip,andsteamwillberelievedthroughthesteamgeneratorPORVsandsafetyvalves.Alowersteamgeneratorreliefvalvepressuresetpointleadstoahigherprimarytosecondarypressuredifferentialandthushigherprimarytosecondaryleakage.Thus,theuseofthelowestsetpointforthesteamgenerator.reliefvalvesisconservativefortheanalysis.SincethePORVsetpointislowerthan.thesafetyvalvesetpoints,theuseofthePORVsetpointof1050psigforsteamreliefismoreconservative,9.PressurizerPressureforSIInitiationTheuseofthemaximumpressurizerpressuresetpointforSIinitiationresultsinearlieractuationoftheSIsystem.Thisleadstothemaintenanceofahigherprimarytosecondarypressuredifferentialandconsequentlyahigherbreakflowrateforalongertimeperiod.Thus,theuseofthemaximumpressurizerpressuresetpointforSIinitiation.intheanalysisisconservative.a,c10.LeakaeafterOverfilla,cOverfillisassumedtooccuriftherupturedsteamgeneratorbecomeswatersolid.Nocreditistakenforsteamlinevolume.1074v:10/112087 WESTINGHOUSEPROPRIETARYCLASS211.FlashinFractiona,cWhencalculatingtheamountofbreakflowthatflashestosteam,100percentofthebreakflowisassumedtocomefromthehotlegsideofthebreak.Sincethetuberuptureflowactuallyconsistsofflowfromthehotlegandcoldlegsidesofthesteamgenerator,thetemperatureofthecombinedflowwillbelessthanthehotlegtemperatureandtheflashingfractionwillbecorrespondinglylower.Thustheassumptionthat100percentofthebreakflowcomesfromthehotlegisconservativeforaSGTRanalysis.C.eratorActionTimesIntheeventofanSGTR,theoperatorisrequiredtotakeactionstostabilizetheplantandterminatetheprimarytosecondaryleakage.Anevaluationhasbeenperformed(reference1)toestablishtheoperatoractiontimesfor'useintheanalysisofadesignbasisSGTRevent.TheoperatoractionswhicharerequiredforrecoveryfromanSGTRandtheavailabledataonthetimestoperformtheseactionshaveb'eenreviewed.TheavailabledataonoperatoractiontimesforanSGTRincludesinformationwhichhasbeenobtainedfromreactorplantsimulatorstudiesaswellasplantdatafromfiveactualSGTRevents.Usingthisdata,operator-actiontimeshavebeenestablished.whichareconsideredtobeappropriateforadesignbasisSGTRevent.TheseoperatoractiontimeswerebeusedasinputfortheanalysisofthedesignbasisSGTRevent.ThemajoroperatoractionsforSGTRrecoverywhichareincludedintheE-3guidelineoftheWestinghouseOwnersGroupEmergencyResponseGuidelineswereexplicitlymodeledintheanalysis.Theoperatoractionsmodeledincludeidentificationandisolationoftherupturedsteamgenerator,cooldownanddepressurizationoftheRCStorestoreinventory,andterminationofSItostopprimarytosecondaryleakage.Theseoperatoractionsaredescribedbelow.1074v:1D/112087 MESTINGHOUSEPROPRIETARYCLASS21.I.dentifytherupturedsteamgenerator(step2).Highsecondarysideactivity,asindicatedbythesteamgeneratorblowdownlineradiationmonitororairejectorradiationmonitor,typicallywillprovidethefirstindicationofanSBTRevent.Therupturedsteamgeneratorcanbeidentifiedbyhighactivityinthecorrespondingsteamgeneratorblowdownline,mainsteamline,orwatersample.ForanSBTRthatresultsinahighpowerreactortrip,thesteamgeneratorwaterlevelwilldecreaseoff-scaleonthenarrowrangeforbothsteamgenerators.Theauxiliaryfeedwater(AFM)flowwillbegintorefillthesteamgenerators,typicallydistributingapproximatelyequalflowtobothsteamgenerators.Sinceprimarytosecondaryleakageaddsadditionalinventorywhichaccumulatesintherupturedsteamgenerator,levelwillreturntothenarrowrangeinthatsteamgeneratorsignificantlyearlierandwillcontinuetoincreasemorerapidly.Thisresponseprovidesconfirmationof.anSGTReventandalsoidentifiestherupturedsteamgenerator.2.Isolatetherupturedsteamgeneratorfromtheintactsteamgeneratorandisolatefeedwatertotherupturedsteamgenerator.(steps3and4).Onceatuberupturehasbeenidentified,recoveryactionsbeginbyisolatingsteamflowfromandstoppingfeedwaterflowtotherupturedsteamgenerator.Inadditiontominimizingradiologicalreleases,thisalsoreducesthepossibilityoffillingtherupturedsteamgeneratorwithwaterby1)minimizingtheaccumulationoffeedwaterflowand2)enablingtheoperatortoestablishapressuredifferentialbetweentherupturedandintactsteamgeneratorsasanecessarysteptowardterminatingprimarytosecondaryleakage.IntheguidelineforsteamgeneratortuberupturerecoveryintheERGs,theoperatorisdirectedtomaintainthelevelintherupturedsteamgeneratorbetweenjustonspanand50%onthenarrowrangeinstrument.Reference1assumedthattherupturedsteamgeneratorwouldbeisolatedwhenlevelinthesteamgeneratorreached[midwaybetweenthesepoints]'074v:1D/112487 WESTINGHOUSEPROPRIETARYCLASS2[(33%narrowrangelevel).]'orGinnaitwasalsoconservativetouse[33percent]'flevelforisolation.Therupturedsteamgeneratorwasassumedtobeisolatedat[33percentnarrowrangelevelorat10minutes,whicheverwaslonger.]'.CooldowntheReactorCoolantSystem(RCS)usingtheintactsteamgenerator(step14).Afterisolationoftherupturedsteamgenerator,theRCSiscooledasrapidlyaspossibletolessthansaturationtemperaturecorrespondingtotherupturedsteamgeneratorpressurebydumpingsteamfromonlytheintactsteamgenerator.Thisensuresadequatesubcoolinginthe.RCSafterdepressurizationtotherupturedsteamgeneratorpressureinsubsequentactions.,Withoffsitepoweravailable,thenormalsteamdumpsystemtothecondenserwillprovidesufficientcapacitytoperformthiscooldownrapidly'.Ifoffsitepowerislost,theRCSiscooledusingthepower-operatedreliefvalve(PORV)ontheintactsteamgeneratorsinceneitherthesteamdumpvalvesnorthecondenserwouldbeavailable.ItisnotedthatRCSpressurewilldecreaseduringthecooldownasshrinkageofthereactorcoolantexpandsthesteambubbleinthepressurizer.4.DepressurizetheRCStorestorereactorcoolantinventory(steps17or18).Whenthecooldowniscompleted,SIflowwillincreaseRCSpressureuntilbreakflowmatchesSIflow.Consequently,SI'flowmustbeterminatedtostopprimarytosecondaryleakage.However,adequatereactorcoolantinventorymustfirstbeassured.ThisincludesbothsufficientreactorcoolantsubcoolingandpressurizerinventorytomaintainareliablepressurizerlevelindicationafterSIflowisstopped.SinceleakagefromtheprimarysidewillcontinueafterSIflowisstoppeduntilRCSandrupturedsteamgeneratorpressuresequalize,an"excess"amountofinventoryisneededtoensure1074v:10/112487 WESTINGHOUSEPROPRIETARYCLASS2pressurizerlevelremainsonspan.The"excess"amountrequireddependsonRCSpressureandreducestozerowhenRCSpressureequalsthepressureintherupturedsteamgenerator.Toreducebreakflowandestablishsufficientpressurizerlevel,RCSpressureisdecreasedbyopeningthepressurizerPORV.5.TerminateSItostopprimarytosecondaryleakage(steps21-23).ThepreviousactionswillhaveestablishedadequateRCSsubcooling,secondarysideheatsink;andreactorcoolantinventoryfollowinganSGTRtoensurethatSIflowisnolongerneeded.Whentheseactionshavebeencompleted,SIflowmustbestoppedtoprevent'epressurizationoftheRCSandtoterminateprimarytosecondaryleakage.PrimarytosecondaryleakagewillcontinueafterSIflowisstoppeduntilRCSpressureandrupturedsteamgeneratorpressuresequalize.Chargingflow,letdown,andpressurizerheaterswillthenbecontrolledtopreventrepressurizationoftheRCS'ndreinitiationofleakageintotherupturedsteam.generator.SincethesemajorrecoveryactionswillbemodelledintheSGTRanalysis,itisnecessarytoestablishthetimesrequiredtoperformtheseactions.Althoughtheintermediatestepsbetweenthemajoractionswillnotbeexplicitlymodelled,itisalsonecessarytoaccountforthetimerequiredtoperformthesteps,Itisnotedthatthetotaltimerequiredtocompletetherecovery-operationsconsistsofbothoperatoractiontimeandsystem,orplant,responsetime;Forinstance,thetimeforeachofthemajorrecoveryoperations(i.e.,RCScooldown,RCSdepressurization,'tc.)isprimarilyduetothetimerequiredforthesystemresponse,whereastheoperatoractiontimeisreflectedbythetimerequiredfortheoperatortoperformtheintermediateactionsteps.'TheoperatoractiontimestoinitiateRCScooldown,RCSdepressurizationandsafetyinjectionterminationweredevelopedinreference1andarelistedinTableII.1.Inadditiontotheoperatoractiontimesdevelopedinreference1,RochesterGasandElectricsuppliedtheoperatoraction1074v:1D/112087 MESTINGHOUSEPROPRIETARYCLASS2timesassociatedwithrecoveringfromthesinglefailures(Reference3).[Theseoperator'actions,whichwouldoccuroutsidethecontrolroom,includelocallyopeningtheintactsteamgeneratorPORV,locallyclosingtheintactsteamgeneratorPORVblockvalveandlocallyclosingthefaultedsteamgeneratorPORVblockvalve.]'hetimesassociatedwithperformingtheseoperatoractionsarelistedinTableII.2.[Itisnotedthatthe20minutestoopentheintactsteamgeneratorPORVconsistsof10minutestoidentifyandlocatethevalveand10minutestolinearlyopenthePORV.DuetolimitationsofLOFTTR2,theoperatoractiontoopentheintactsteamgeneratorPORVwassimulatedasastepopeningaftera15minutedelay,whichresultsinanequivalentintegratedsteamflowthroughthePORVattheendofthe20minuteperiod.]'074v:io/11208710 MESTINGHOUSEPROPRIETARYCLASS2TABLEII.1OPERATORACTIONTIMESFORDESIGNBASISSGTRANALYSISActionTimeminIdentifyandisolaterupturedSGHaximumof10minorcalculatedtimetoreach334narrowrangelevelintherupturedSGOperatoractiontimetoinitiatecooldownCooldownCalculatedtimeforRCScooldownOperatoractiontimetoinitiatedepressurizationDepressurizationCalculatedtimeforRCSdepressurizationOperatoractiontimetoinitiateSIterminationSIterminationandpressureequalizationCalculatedtimeforSIterminationandequalizationofRCSandrupturedSGpressures1074v:1D/112087 WESTINGHOUSEPROPRIETARYCLASS2TABLEII.2ActionGINNASPECIFICOPERATORACTIONTIMESTimeminQ,CFaultedSteamGeneratorPORVBlockValveClosing-LocalAction15IntactSteamGeneratorPORVOpening-LocalAction20IntactSteamGeneratorPORVBlockValveClosing-LocalAction1074v:1D/11208712 II'ESTINGHOUSEPROPRIETARYCLASS2D.TransientDescrition-Case1[Case1addressesaSGTRinwhichthesinglefailureassumedisthattheintactsteamgeneratorPORVfailstoopenondemandandmustbelocallyopened.]'hesequence,ofeventsforCase1ispresentedinTableII.3.Followingthetuberupture,reactorcoolantflowsfromtheprimaryintothesecondarysideoftherupturedsteamgeneratorsincetheprimarypressureisgreaterthanthesteamgeneratorpressure.Inresponsetothislossofreactorcoolant,pressurizerleveldecreasesasshowninFigureII.1.TheRCSpressurealsodecreasesasshowninFigureII.2asthesteambubbleinthepressurizerexpands.AstheRCSpressuredecreasesduetothecontinuedprimarytosecondaryleakage,automaticreactortripoccursonanovertemperaturedelta-Ttripsignal.Afterreactortrip,corepowerrapidlydecreasestodecayheatlevels.Theturbinestopvalvescloseandsteamflowtotheturbineisterminated.Thesteamdumpsystemisdesignedtoactuatefollowingreactortriptolimittheincreaseinsecondarypressure,butthesteamdumpvalvesremainclosedduetothelossofcondenservacuumresultingfromtheassumedlossofoffsitepoweratthetimeofreactortrip.Thus,theenergytransferfromtheprimarysystemcausesthesecondarysidepressuretoincreaserapidlyafter'reactortripuntilthesteamgenerator.PORVslifttodissipatetheenergy,asshowninFigureII.3.TheRCSpressuredecreasesmorerapidlyafterreactortripasenergytransfertothesecondaryshrinksthereactorcoolantandtheleakflowcontinuestodepleteprimaryinventory.ThedecreaseinRCSinventoryresultsinalowpressurizerpressureSIsignal.PressurizerlevelalsodecreasesmorerapidlyfollowingreactortripandthepressurizereventuallyemptiesasshowninFigureII.1.Afterthepressurizerempties,theRCSpressurerapidlydecreasesasshowninFigureII.2.1074v:10/12048713 WESTINGHOUSEPROPRIETARYCLASS2Sinceoffsitepowerisassumedlostatreactor-trip,theRCPstripandagradualtransitiontonaturalcirculationflowoccurs.Immediatelyfollowingreactortripthetemperatureriseacrossthecoredecreasesascorepowerdecays(seeFigure11.4),however,thetemperaturerisesubsequentlyincreasesasnaturalcirculationflowdevelops.Thecoldlegtemperaturestrendtowardthesteamgeneratortemperatureasthefluidresidencetimeinthetuberegionincreases.TheRCStemperaturescontinuetoslowlydecreaseduetothecontinuedadditionoftheauxiliaryfeedwatertothesteamgeneratorsuntiloperatoractionsareinitiatedtocooldowntheRCS.majorOperatorActions1.IdentifyandIsolatetheRupturedSteamGeneratorOnceatuberupturehasbeenidentified,recoveryactionsbeginbyisolatingsteamflowfromtherupturedsteamgeneratorand.throttlingtheauxiliaryfeedwaterflowtotherupturedsteamgenerator.Asindicatedpreviously,therupturedsteamgeneratorisassumedtobeidentifiedandisolatedwhenthenarrowrangelevelreaches[33%]'ntherupturedsteamgeneratororat[10]'inutesafter.initiationoftheSGTR,whicheverislonger.ForGinna,thetimetoreach[33%]'slessthan[10]'inutes,thustherupturedsteamgeneratorisassumedtobeisolatedat[10]'inutes.2.CooldowntheRCStoEstablishSubcoolingMarginAfterisolationoftherupturedsteamgenerator,thereisa[5]'inuteoperator.actiontimeimposedpriortoinitiatingthecooldown.Theactualdelaytimeusedintheanalysisis4secondslongerbecauseofthecomputerprogramrequirementsforsimulatingtheoperatoractions.Afterthistime,actionsaretakentocooltheRCSasrapidlyaspossiblebydumpingsteamfromtheintactsteamgenerators.Sinceoffsitepowerislost,theRCSiscooledbydumpingsteamtotheatmosphereusingthePORVontheintactsteamgenerator.[ForCase1,aspreviouslynoted,theintactsteamgenerator]'074v:1D/11248714 MESTINGHOUSEPROPRIETARYCLASS2[PORVfailstoopen.Fortheanalysis,itwasassumedthatthevalvewasfullyopenedafteranadditionalperiodof15minutes(seepg.10).Thusat1804secondstheintactsteamgeneratorPORVisopenedforRCScooldown.]'hecooldowniscontinuedunti1RCSsubcoolingattherupturedsteamgeneratorpressureis20'Fplusanallowanceof17'Fforsubcoolinguncertainty.[WhentheseconditionsaresatisfieditisassumedthatittakestheoperatorfiveminutestoclosetheintactsteamgeneratorPORVblockvalve.]'tisnotedthatoverfilloftherupturedsteamgeneratoroccursduringthistimeperiodat'[2372]'econds,asshowninFigureII.6.ThiscooldownensuresthattherewillbeadequatesubcoolingintheRCSafterthesubsequentdepressurizationoftheRCStotherupturedsteamgeneratorpressure.ThereductionintheintactsteamgeneratorpressurerequiredtoaccomplishthecooldownisshowninFigureII.3,andtheeffectofthecooldownontheRCStemperatureisshowninFigureII.4.TheRCSpressurealsodecreasesduringthiscooldownprocessduetoshrinkageofthereactorcoolantasshowninFigureII.2.3,DepressurizeRCStoRestoreInventoryAftertheRCScooldown,a[2]'inuteoperatoractiontimeisincludedpriortodepressurization.TheRCSisdepressurizedat2688secondstoassureadequatecoolantinventorypriortoterminatingSIflow.MiththeRCPsstopped,normalpressurizer'prayisnotavailableandthustheRCSisdepressurizedbyopeningapressurizerPORV.Thedepressurizationiscontinueduntilanyofthefollowingconditionsaresatisfied:RCSpressureislessthantherupturedsteamgeneratorpressureandpressurizerlevelisgreaterthan0%plusanallowanceof3%forpressurizerleveluncertainty,orpressurizer,levelisgreaterthan80%minusanallowanceof3%forpressurizerleveluncertainty,orRCSsubcoolingislessthanthe17'Fallowanceforsubcoolinguncertainty.TheRCSdepressurizationreducesthebreakflowasshowninFigureII.5andincreasesSIflowtorefillthepressurizer,asshowninFigureII.1.1074v:10/11248715 WESTINGHOUSEPROPRIETARYCLASS24.TerminateSItoStopPrimarytoSecondaryLeakageThepreviousactionsshouldhaveestablishedadequateRCSsubcooling,verifiedasecondarysideheatsink,andrestoredthereactorcoolantinventoryfollowingaSGTRtoensurethatSIflowisnolongerneeded.Whentheseactionshavebeencompleted,theSIflowmustbestoppedtopreventrepressurizationoftheRCSandtoterminate"primarytosecondaryleakage.TheSIflowisterminatedwhentheRCSpressureincreases,,minimumAFWflowisavailableandatleastoneintactsteamgeneratorlevelisinthenarrowrange,RCSsubcoolingisgreaterthanthe17'Fallowanceforsubcoolinguncertainty,andthepressurizerlevelisgreaterthanthe3Xallowanceforpressurizerleveluncertainty.ToassurethattheRCSpressureisincreasing,SIwasnotterminatedintheanalysisuntiltheRCSpressureincreasedto50psiabovetherupturedsteamgeneratorpressure.Afterdepressurizationiscompleted,anoperatoractiontimeof[1]'inuteisimposedpriortoSItermination.TheprimarytosecondaryleakagecontinuesaftertheSIflowisterminateduntiltheRCSandrupturedsteamgeneratorsequalize.Thisoccurswhen'theintactsteamgeneratorPORVislocallyopenedtocooldowntheRCSsothatsubcoolingmaybemaintained.WhenthePORVisopenedtheincreasedenergytransferfromprimarytosecondarydepressurizestheRCStotheruptured.steamgeneratorpressure.1074v:10/11208716 MESTINGHOUSEPROPRIETARYCLASS2TABLEII.3SEQUENCEOFEVENTSEVENTCASE1Timesecd.,CReactorTrip50Ruptured.SGIsolated600IntactSGPORVOpened1804OverfillRupturedSG2372IntactSGPORVIsolatedPRZRPORVOpenedPRZRPORVClosed256826882738SITerminated2798IntactPORVOpened3288BreakFlowTerminated34281074v:1D/11208717 WESTINGHOUSEPROPRIETARYCLASS2GINNASTEAMGENERATORTUBERUPTUREANALYSIS15PERCENTTUBEPLUGGINGCASE1188.88~78.68.4J68.t448.38.18~8.8..1Ei84.2E+84TINE(SEC).3Ei84.4E~84FigureII.1PressurizerLevel-Case11074v:1D/11208718 MESTINGHOUSEPROPRIETARYCLASS2GINNASTEAMGENERATORTUBERUPTUREANALYSIS15PERCENTTUBEPLUGGINGCASEI.25E+84.225Ei84.2E84.175E'84.15E+84Ld~,12SE~84LJOf~o.1E84Of758.588.258..IE~84.2E84.3E~84TIME(SEC).4E84FigureII.2RCSPressure-Case11074v:10/11208719 MESTINGHOUSEPROPRIETARYCLASS2GINNASTEAMGENERATORTUBERUPTUREANALYSISISPERCENTTUBEPLUGGINGCASEI.I4E84.12Ei84RUPTUREDLOOP.1E~84888.INTACTLOOPOCC)ill688.488.288.8..IE~84.2E84.3E~84.4E~84TINE(SEC)FigureII.3SecondaryPressure-Case11074v:1D/11208l20 MESTINGHOUSEPROPRIETARYCLASS2GINNASTEAi1GENERATORTUBERUPTUREANALYSISPERCENTTUBEPLUGGINGCASE1658.688.~558.4JCD588.~458.IX488.C)358.CDCD~388.258~288'..1E~84..2E~84TI11E(SEC).3E~84~4E~84FigureII.4IntactLoopHotandColdLegRCSTemperatures-Case11074v:10/11208721 MESTINGHOUSEPROPRIETARYCLASS2GINNASTEAI1GENERATORTUBERUPTUREANALYSIS15PERCENTTUBEPLUGGINGCASE1168.I48.128'SSUEUlKlD88.C)68~hCEZIIJm48.28.-28...IE~84.2E~84TIt1EISEC).3E84.4E+84FigureII.5PrimarytoSecondaryLeakage-Case11074v:1D/11208722 MESTINGHOUSEPROPRIETARYCLASS2GINNASTEAI1GENERATORTUBERUPTUREANALYSIS15PERCENTTUBEPLUGGINGCASE1.6E84.SE84~.4E~84~.3'40.2Ei84.1E84.lE.84.2E~B4.3E~84.4E~84TlNEtSEC)FigureII.SRupturedSGRaterVolume-Case11074v:1D/11208123 WESTINGHOUSEPROPRIETARYCLASS2E.TransientDescrition-Case2[Case2addressesaSGTRinwhichthesinglefailureassumedisthatthefaultedsteamgeneratorPORVfailsopenatthetimethefaultedsteamgeneratorisisolated.]'hus,theCase2transientissimilartotheCase1transientuntilthattime..ThesequenceofeventsforCase2isIpresentedinTableII.4.FollowingthetuberupturetheRCSpressuredecreasesasshowninFigure11.7duetotheprimarytosecondaryleakage.Inresponsetothisdepressurization,thereactortripsonovertemperaturedelta-T.Afterreactortrip,corepowerrapidlydecreasestodecayheatlevelsandtheRCSdepressurizationbecomesmorerapid.Thesteamdumpsystemisinoperableduetotheassumedlossofoffsitepower,whichresultsinthesecondarypressurerisingtothesteamgeneratorPORVsetpointasshowninFigure11.8.ThedecreasingpressurizerpressureleadstoanautomaticSIsignalonlowpressurizerpressure.Pressurizerlevelalsodecreasesmorerapidlyfollowingreactortripuntiliteventuallyempties,asshowninFigure11.9.majorOperatorActions1.IdentifyandIsolatetheRupturedSteamGeneratorTherupturedsteamgeneratorisassumedtobeidentifiedandisolatedat[10minutesaftertheinitiationoftheSGTRorwhenthenarrowrangelevelreaches33%,whichevertimeisgreater.]'orthiscase,thetimetoreach[33/]'arrowrangelevelis[652]'econds,andthus,itwasassumedthattherupturedsteamgeneratorisisolatedatthattime.[TherupturedsteamgeneratorPORVisalsoassumedtofailopenatthistime.]'hefailurecausesthesteamgeneratortorapidlydepressurize,whichresultsinanincreaseinprimarytosecondaryleakage.Thedepressu'rizationoftherupturedsteamgeneratorincreases'hebreakflowandenergytransferfromprimarytosecondarywhichresultsinRCSpressureandtemperaturedecreasingmorerapidlythaninCase1.Therupturedsteamgenerator1074v:10/12048724 MESTINGHOUSEPROPRIETARYCLASS2depressurizationcausesacooldownintheintactsteamgeneratorloop.Asthe'ntactsteamgeneratorhotlegtemperaturedecreasesbelowthesteamgeneratorwatertemperaturereverseheattransfertakesplaceasshowninFigureII.10.[ItisassumedthatthetimerequiredfortheoperatortoidentifythattherupturedsteamgeneratorPORVisopenandtoclosetheassociatedblockvalveis15minutes.Thus,at1558secondsthedepressurizationofrupturedsteamgeneratoristerminated.]',c2.CoolDowntheRCStoestablishSubcoolingMargin[AftertherupturedsteamgeneratorPORVblockvalveisclosed,'hereisa5minuteoperatoractiontimeimposedpriortoinitiationofcooldown.]'hedepressurizationoftherupturedsteamgeneratoraffectstheRCScooldowntargettemperaturesincethetemperatureisdependentuponthepressureintherupturedsteamgenerator.Since'ffsitepowerislosttheRCSiscooledbydumpingsteamtotheatmosphereusingtheintactsteamgeneratorPORV.ThecooldowniscontinueduntilRCSsubcoolingattherupturedsteamgeneratorpressureis20'Fplusanallowanceof17'Fforinstrumentuncertainty.HecauseofthelowerpressureintherupturedsteamgeneratortheassociatedtemperaturetheRCSmustbecooledtoisalsolower,whichhastheneteffectofextendingthetimeforcooldown.ForCase2cooldownbeginsat[1858]'econds'andiscompletedat[2852]'econds.ThereductionintheintactsteamgeneratorpressurerequiredtoaccomplishthecooldownisshowninFigureII.8,andtheeffectofthecooldownontheRCStemperatureisshowninFigureII.10.TheRCSpressurealsodecreasesduringthiscooldownprocessduetoshrinkageofthereactorcoolantasshowninFigureII.7.3.DepressurizetoRestoreInventoryAftertheRCScooldown,a[2]'inuteoperatoractiontimeisincludedpriortodepressurization.TheRCSisdepressurizedat[2974]'econdstoassureadequatecoolantinventorypriorto1074v:10/11248725 HESTINGHOUSEPROPRIETARYCLASS2terminatingSIflow,-HiththeRCPsstopped,normalpressurizersprayisnotavailableandthustheRCSisdepressurizedbyopeningapressurizerPORV.Thedepressurizationiscontinueduntilanyofthefollowingconditionsaresatisfied:RCSpressureislessthantherupturedsteamgeneratorpressureandpressurizerlevelisgreaterthan0%plusanallowanceof3%forpressurizerleveluncertainty,orpressurizerlevelisgreaterthan80%minusanallowanceof3%forpressurizerleveluncertainty,orRCSsubcoolingislessthanthe17'Fallowanceforsubcoolinguncertainty.TheRCSdepressurizationreducesthebreakflowasshowninFigureII.11andincreasesSIflowtorefillthepressurizer,asshowninFigure11.9.4.TerminateSItoStopPrimarytoSecondaryLeakage,ThepreviousactionsshouldhaveestablishedadequateRCSsubcooling,verifiedasecondarysideheatsink,andrestoredthereactorcoolantinventoryfollowinganSGTRtoensurethatSIflowisnolongerneeded.Nhentheseactionshavebeencompleted,theSIflowmustbestoppedtopreventrepressurizationoftheRCSandtoterminateprimarytosecondaryleakage.TheSIflowisterminatedwhentheRCSpressureincreases,'minimumAFHflowisavailableandatleastoneintactsteamgeneratorlevelisinthenarrowrange,RCSsubcoolingisgreaterthanthe17'Fallowanceforsubcoolinguncertainty,andthepressurizerlevelisgreaterthanthe3%allowanceforpressurizerleveluncertainty.ToassurethattheRCSpressureisincreasing,SIwasnotterminateduntiltheRCSpressureincreasedto50psiabovetherupturedsteamgeneratorpressure.Afterdepressurizationiscompleted,anoperatoractiontimeof[1]'inuteisimposedpriortoSItermination.FigureII.11showsthattheprimarytosecondaryleakagecontinuesaftertheSIflowisstoppeduntiltheRCSandrupturedsteamgeneratorpressureequalize.TherupturedsteamwatervolumeisshowninFigureII.12.ForCase2,therupturedsteamgeneratordoesnotoverfill.1074v:1D/112487 MESTINGHOUSEPROPRIETARYCLASS2TABLEII.4SEQUENCEOFEVENTSCASE2EVENTTIMEsecReactorTrip49.4RupturedSGIsolatedRupturedSGPORVFailsOpena.cRupturedSGBlockValveClosed1558IntactSGPORVOpenedIntactSGPORVClosed18582852PRZRPORVOpenedPRZRPORVClosed29743006SITerminated3066BreakFlowTerminated34381D74v:1O/11208727 WESTINGHOUSEPROPRIETARYCLASS2GINNASTEAt1GENERATORTUBERUPTURE4NAL'/SIS15PERCENTTUBEPLUGGING2588.2258.CASE2-2888.CCl758.1588.~1258.cnI888.758.588.258.8.8.588.1888.l588.2888'588.5888.5588."4888.TIME(SEC)FigureII.7RCSPressure-Case21074v:10/11208728 HESTINGHOUSEPROPRIETARYCLASS21488.GINNASTEAMGENERATORTUBERUPTUREANALYSIS15PERCENTTUBEPLUGGINGCASE21288.-l888.w888.688.w488,RUPTUREDLOOPINTACTLOOP288,8.588.1888.:l588.2888.2588.3888.3588.4888.TIME(SEC)FigureII.8SecondaryPressure-Case21074v:10/11208729 WESTINGHOUSEPROPRIETARYCLASS2G1NNASTEANGENERATORTUBERUPTUREANALYS1515PERCENTTUBEPLUGGING188.CASE298.e8.78.LJw68.'58.48~38.028.18.8.8.588.1888.1588.2888'588.3888.3588.4888.TINE(SEC)FigureII.9PressurizerLevel-Case.21074v:10/11ZOST30 MESTINGHOUSEPROPRIETARYCLASS2GINNASTEAMGENERATORTUBERUPTUREANALVSIS15PERCENTTUBEPLUGGING658.CASE2688.~558.O588.~z.458.o488.xIo358,388.TCOLDTHOTTHOT,TCOLDTHOTTCOLD258'88.8.588.1888.1588.2888.2588.3888.3588.4888.TIME(SEC)FigureII.10IntactLoopHotandColdLegRCSTemperatures-Case21074v:1D/11208731 MESTINGHOUSEPROPRIETARYCLASS2GINNASTEAMGENERATORTUBERUPTUREANALVSIS15PERCENTTUBEPLUGGINGCASE278.w68~58.o48.38.oc28.I8,-18.-288.588.1888.1588.2888.2588.3888.3588.4888.TIME(SEC)FigureII.11PrimarytoSecondaryLeakage-Case21074v:1D/11208732 MESTINGHOUSEPROPRIETARYCLASS26888.GINNASTEAMGENERATORTUBERUPTUREANALYSIS15PERCENTTUBEPLUGGING'ASE2H)I~5888.Ko4888.~5888.~g2888~I888.8.588.1888.1588.2888.2588.5888.5588.4888.,TIME(SEC)Figure11,12RupturedSGMaterVolume-Case21074v:1D/11208733 WESTINGHOUSEPROPRIETARYCLASS2F.MassReleasesThemassreleasesweredeterminedforeachofthesinglefailurecasesforuseinevaluatingtheexclusionareaboundaryandlowpopulationzoneradiationexposure.Thesteamreleasesfromtherupturedandintactsteamgenerators,thefeedwaterflowstotherupturedandintactsteamgenerators,andprimarytosecondarybreakflowintotherupturedsteamgeneratorweredeterminedfortheperiodfromaccidentinitiationuntil2hoursaftertheaccidentandfrom2to8hoursaftertheaccident.Thereleasesfor0-2.hoursareusedtocalculatetheradiationdosesattheexclusionareaboundaryfora2hourexposure,andthereleasesfor0-8hoursareusedtocalculatetheradiationdosesatthelowpopulationzoneforthedurationoftheaccident.IntheLOFTTR2analyses,theSGTRrecoveryactionsintheE-3guidelineweresimulateduntiltheterminationofprimarytosecondaryleakage.Aftertheprimarytosecondaryleakageisterminated,theoperatorswillcontinuetheSGTRrecoveryactionsintheE-3guidelinetopreparetheplantforcooldowntocoldshutdownconditions.TheseactionsincludeestablishingnormalChemicalandVolumeControlSystem(CVCS)operationtoprovidereactorcoolantinventorycontrolandaborationpath;restartingareac'torcoolantpump(RCP),ifnonearerunning,toensurehomogeneousRCSconditionsandtoprovidenormalpressurizerspray;orstoppingoneRCP,ifbotharerunning,tominimizetheheatinput'uringthesubsequentcooldown;andtheactionsnecessaryto'inimizethespreadofcontaminationonthesecondaryside.WhentheinstructionsprovidedinE-3arecompleted,theplantshouldbecooledanddepressurizedtocoldshutdownconditions.Therearethreealternatemeansofperformingthepost-SGTRcooldownprovidedintheWOGEmergencyResponseGuidelines.Theguidelinesare:ES-3.1,POST-SGTRCOOLDOWNUSINGBACKFILL;ES-3.2,POST-SGTRCOOLDOWNUSINGBLOWDOWN;andES-3.3,POST-SGTRCOOLDOWNUSINGSTEAMDUMP.Thepreferredmethodsareusingbackfillorblowdownsincethesemethodsminimizetheradioactivityreleasedtotheatmosphere.TheES-3.3guidelineusingsteamdumpprovidesthefastestmethodfor1074v:1D/11208734 WESTINGHOUSEPROPRIETARYCLASS2depressurizingtheRCSandrupturedsteamgenerator.Thismethodalsoresultsintheworstradiologicalreleases,especiallyifsteamdumptothecondenserisunavailable.Therefore,themethodusingsteamdumpwasselectedforevaluationofthelong-termmassreleasessincethisproducesconservativeresultsfortheoffsitedoseevaluation.Itisnotedthattheuseofthesteamdumpmethodwouldnotbepermittedifsteamgeneratoroverfilloccursandwaterentersthemainsteamlines.ThehighlevelactionsfortheES-3.3guidelinearediscussedbelow,1.PrepareforCooldowntoColdShutdownTheinitialstepstoprepareforcooldowntocoldshutdownareperformedintheE-3guidelinefollowingSItermination,andthesestepswillbecontinuedinES-3.3iftheyhavenotalreadybeencompleted.AfewadditionalstepsarealsoperformedinES-3.3prior.toinitiatingcooldown.Theseincludeisolatingthecoldleg.SIaccumulatorstopreventunnecessaryinjection,energizingpressurizerheatersasnecessarytosaturatethepressurizerwaterandtoprovideforbetterpressurecontrol,andassuringadequateshutdownmarginintheeventofpotentialborondilutionduetoin-leakagefromthe'rupturedsteamgenerator.2.CooldownRCStoResidualHeatRemoval(RHR)SystemTemperatureTheRCSiscooledbysteamingandfeedingtheintactsteamgeneratorsimilartoanormalcooldown.Sinceallimmediatesafetyconcernshavebeenresolved,thecooldownrateshouldbemaintainedlessthanthemaximumallowablerateof100'F/hr.ThepreferredmeansforcoolingtheRCSissteamdumptothecondensersincethisminimizestheradiologicalreleasesandconservesfeedwatersupply.ThePORVfortheintactsteamgeneratorcanalsobeusedifsteamdumptothecondenserisunavailable.WhentheRHRsystemoperatingtemperatureisreached,thecooldownisstoppeduntilRCSpressurecanalsobedecreased.Thisensuresthatpressure/temperaturelimitswillnotbeexceeded.1074v:1D/11208735 WESTINGHOUSEPROPRIETARYCLASS23.DepressurizeRCStoRHRSystemPressureWhenthecooldowntoRHRsystemtemperatureiscompleted,thepressureintherupturedsteamgeneratorisdecreasedbyreleasingsteamfromtherupturedsteamgenerator.Steamreleasetothecondenserispreferredsincethisminimizesradiologicalreleases.However,steamcanalsobereleasedtotheatmosphereusingthePORVontherupturedsteamgenerator.Anevaluationofthepotentialradiologicalconsequencesshouldbeperformedbeforereleasingsteamfromtherupturedsteamgeneratortotheatmosphere.Astherupturedsteamgeneratorpressureisreduced,theRCSpressureismaintainedequaltothepressureintherupturedsteamgeneratorinordertopreventin-leakageofsecondarysidewateroradditionalprimarytosecondaryleakage.NormalpressurizersprayisthepreferredmeansofRCSpressurecontrolsincethisconservescoolantinventory.Ifpressurizersprayisnotavailable,apressurizerPORVorauxiliaryspraycanbeusedtocontrolRCSpressure.Whenoverfilloftherupturedsteamgeneratoroccurs,aswithCase1,guidelineES-3.1POST-SGTRCOOLDOWNUSINGBACKFILLisassumedtobeused.ThehighlevelactionsforES-3.1aresimilartoES-3.3.However,themethodbywhichES-3.1instructstheoperatortodepressurizetherupturedsteamgeneratordiffersfromES-3.3.InGuidelineES-3.1theRCSisdepressurizedtopromotebackflowthroughthefailedtubewhichdepressurizestherupturedsteamgeneratorwithoutsteamreleasestotheatmosphere.4.CooldowntoColdShutdownWhenRCStemperatureandpressurehavebeenreducedtotheRHRsystemin-servicevalues,RHRsystemcoolingisinitiatedtocompletethecooldowntocoldshutdown.Whencoldshutdownconditionsareachieved,thepressurizercanbecooledtoterminatetheevent.1074v:1O/11208736 WESTINGHOUSEPROPRIETARYCLASS2F.1MethodologyforCalculationofMassReleasesTheoperatoractionsfortheSGTRrecoveryuptotheterminationofprimarytosecondaryleakagearesimulatedintheLOFTTR2analyses.Thus,thesteamreleasesfromtherupturedandintactsteamgenerators,thefeedwaterflowstotherupturedandintactsteamgenerators,andtheprimarytosecondaryleakageintotherupturedsteamgeneratorweredeterminedfromtheLOFTTR2resultsfortheperiodfromtheinitiationoftheaccidentuntiltheleakageisterminated.L2,CFollowingtheterminationofleakage,theoperatorsareassumedtocompletethestepsintheE-3andES-3.3orES-3.1guidelinestoprepareforcooldowntocoldshutdown.Thetimefromleakageterminationuntiltheinitiationofcooldownwasassumedtobe20minutes(seeReference2).Theassumedtimeof20minutestoinitiatethecooldownisconsideredtobeconservative,sincetheactualtimeisexpectedtobelongerforanactualeventbecauseanevaluationofthepotentialoffsiteradiationdoseswouldberequiredpriortousingthesteamdumpmethodforthepost-SGTRcooldown.ItwasassumedthattheRCSandintactsteamgeneratorconditionsaremaintainedstableduringthe20minuteperioduntilthecooldownisinitiated.ThePORVfortheintactsteamgeneratorwasthenassumedtobeusedtocooldowntheRCStotheRHRsystemoperatingtemperatureof332'F,atthemaximumallowablecooldownrateof100'F/hr..TheRCSandtheintactsteamgeneratortemperaturesat2hourswerethendeterminedusingtheRCSandintactsteamgeneratorparametersatthetimeofleakageterminationandtheRCScooldownrate.'hesteamreleasesandthefeedwaterflowsfortheintactsteamgeneratorfortheperiodfromleakageterminationuntil2hoursweredeterminedfromamassandenergybalanceusingthecalculatedRCSandintactsteamgeneratorconditionsatthetimeofleakageterminationandat2hours.ThecoredecayheatandtheheataddedfromtheoperationofoneRCPwereincludedintheenergybalanceforthistimeperiod.Sincetherupturedsteamgeneratorisisolated,nochangeintherupturedsteamgeneratorconditionsisassumedtooccuruntilsubsequentdepressurization.TheassumptionsofareasonablyshortpreparationtimeforcooldownandthemaximumcooldownrateresultinminimumRCSandsteamgeneratortemperaturesat2hours,andtherefore,aconservativeestimateofthesteamreleasedtotheatmosphereduringthefirst2hours.1074v:1D/11208737 HESTINGHOUSEPROPRIETARYCLASS2a,c'TheRCScooldownwasassumedtobecontinuedafter2hoursuntiltheRHRsystemin-servicetemperatureof332'Fisreached.DepressurizationoftherupturedsteamgeneratorwasthenassumedtobeperformedimmediatelyfollowingthecompletionoftheRCScooldown.TherupturedsteamgeneratorwasassumedtobedepressurizedtotheRHRin-servicepressureof343psiaviasteamreleasefromtherupturedsteamgeneratorPORV,sincethismaximizesthesteamreleasefromrupturedsteamgeneratortotheatmospherewhichisconservativefortheevaluationoftheoffsiteradiationdoses.TheRCSpressureisalsoassumedtobereducedconcurrentlyastherupturedsteamgeneratorisdepressurizedtominimizeflowbetweentheRCSandtherupturedsteamgenerator.ItisassumedthatthecontinuationoftheRCScooldownanddepressurizationtoRHRoperatingconditionsarecompletedwithin8hoursaftertheaccidentsincethereisampletimetocompletetheoperationsduringthistimeperiod.Thesteamreleasesandfeedwaterflowsfrom2to8hoursweredeterminedfortheintactsteamgeneratorfromamassandenergybalanceusingtheRCSandsteamgeneratorconditionsat2hoursandattheRHRsystemin-serviceconditions.ThecoredecayheatandtheheatadditionduetotheoperationofoneRCPwerealsoincludedintheenergybalanceforthistimeinterval.Thesteamreleasedfromtherupturedsteamgeneratorfrom2to8hourswasdetermined.based'namassandenergybalancefortherupturedsteamgeneratorusingtheconditionsatthetimeofleakageterminationandsaturatedconditionsattheRHRin-servicepressure.After8hours,itisassumedthatfurtherplantcooldowntocoldshutdownaswellaslong-termcoolingisprovidedbytheRHRsystem.Therefore,thesteam~releasestotheatmosphereareterminatedafterRHRin-serviceconditionsareassumedtobe.reachedat8hours.F.2HassReleaseResultsThemassreleasecalculationswereperformedforbothsinglefailurecasesusingthemethodologydiscussedabove.Forthetimeperiodfrominitiationoftheaccidentuntilleakagetermination,thereleasesweredeterminedfromtheLOFTTR2resultsfortwoseparateperiodsforuseinthedosecalculations.Thefirsttimeperiodconsideredisfromaccidentinitiationuntilreactortrip.Sincethecondenserisinserviceuntilreactortrip,anyradioactivity1074v:1D/11208738 WESTINGHOUSEPROPRIETARYCLASS2releasedtotheatmospherepriortoreactortripwillbethrough'hecondenserairejector.Afterreactortrip,'hereleasestotheatmosphereareassumedtobeviathesteamgeneratorPORVs.Themassreleasescalculatedfromthetimeofleakageterminationuntil2hoursandfrom2-8hoursarealsoassumedtobereleasedtotheatmosphereviathesteamgeneratorPORVs.ThemassreleasesfortheSGTRevent[assumingdelayeduseoftheintactsteamgeneratorPORV]'Case1)arepresentedinTableII.5.Theresultsindicatethatapproximately[21,990]'bmofsteamand[23,710]'bmofwaterisreleasedfromtherupturedsteamgeneratortotheatmosphereinthefirst2hours.Atotalof[129,300]'bmofprimarywateristransferredtothesecondarysideoftherupturedsteam.generatorbeforethebreakflowisterminated.ThemassreleasesfortheSGTReventassuming[failureandisolationoftherupturedsteamgeneratorPORV]'Case2)arepresentedinTableII.6.Theresultsindicatethatapproximately[62,480]'bmofsteamisreleasedtotheatmospherefromtherupturedsteamgeneratorwithinthefirst2hours.After2hours[33,300]'bmisreleasedtotheatmospherefromtherupturedsteamgenerator.Atotalof[172,800]'bmofprimarywateristransferredtothesecondarysideoftherupturedsteamgeneratorbeforebreakflowisterminated.1074v:1D/11208739 MESTINGHOUSEPROPRIETARYCLASS2TABLEII.5CASE1MASSRELEASES0-TRIPTOTALMASSFLOW(POUNDS)TIMEPERIODTRIPTMSEP-OVFILL-TTBRK-T2HRSTMSEPOVFILLTTBRKT2HRS'RHRFaultedSGCondenserAtmosphereFeedwater47,80000015,450654043,60030,50000023,710*'00PICIntactSGCondenserAtmosphere47,150Feedwater47,1500000014,73032,95013,450151,870505,50046,04029,61017,900158,700513,500BreakFlow421647,57453,71023,800TRIPTMSEPOVFILLTTBRKT2HRSTRHR=Timeofreactortrip=[50]'ec.=Timewhenwaterreachesthemoistureseparators=[1086]'ec.=Timewhensteamgeneratoroverfills=[2372]'ec.=Timewhenbreakflowisterminated=[3428]'ec.=Timeat2hours=7200sec.=TimetoreachRHRin-serviceconditions,8hours=28,800sec.*Ha'ter1074v:1D/1120Sl40 MESTINGHOUSEPROPRIETARYCLASS2TABLEII.6CASE2MASSRELEASES~TOTALMASSFLOM(POUNDS)TIMEPERIOD0-TRIPTRIPTMSEP"TTBRK-T2HRSTMSEPTTBRKT2HRSTRHRFaultedSGCondenserAtmosphereFeedwater46,8800062,09039042,74033,260033,300CL,CIntactSGCondenserAtmosphereFeedwater46,220000035,43018,450153,920457,00046,22097,78019,700160,300457,700BreakFlow4134132,66636,00000TRIP=TimeTMSEP=TimeTTBRK=TimeT2HRS=TimeTRHR=Timeofreactortrip=[49.4]'ec.whenwaterreachesthemoistureseparators=[2372]'ec.whenbreakflowisterminated=[3438]'ec.at2hours=7200sec.toreachRHRin-serviceconditions,8hours=28,800sec.1074v:1D/11208741 MESTINGHOUSEPROPRIETARYCLASS2TABLEII.7SUMMARIZEDMASSRELEASESTOTALMASSFLOM(POUNDS)CASE1CASE2FaultedSG0-TTBRKTTBRK-2HRS-2HRS8HRS0-TTBRK-2HRSTTBRK2HRS8HRSCondenser47,82046,880Atmosphere45,700*62,48033,300Feedwater74,10076,000IntactSGCondenser47,15046,2200Atmosphere61,130151,870505,500Feedwater122,800158,700513,50053,880153,920457,000163,700160,300.457,700BreakFlow129,3000172,800023,710ibmofthisiswater.1074v:10/1120S742 WESTINGHOUSEPROPRIETARYCLASS2III.RADIOLOGICALCONSEQUENCESANALYSISTheevaluationoftheradiologicalconsequencesofasteamgeneratortuberupture,assumesthatthereactorhasbeenoperatingattheproposedTechnicalSpecificationlimitforprimarycoolantactivityandattheexistingTechnicalSpecificationlimitforprimarytosecondaryleakageforsufficienttimetoestablishequilibriumconcentrationsofradionuclidesinthereactorcoolantandinthesecondarycoolant.Radionuclidesfromtheprimarycoolantenterthesteamgenerator,viatherupturedtube,andarereleasedtotheatmospherethroughthesteamgeneratorsafetyorpoweroperatedreliefvalvesandviathe4condenserairejector,exhaust.Thequantityofradioactivityreleasedtotheenvironment,duetoaSGTR,dependsuponprimaryandsecondarycoolantactivity,iodinespikingeffects,primarytosecondarybreakflow,breakflowflashingfractions,attenuationofiodinecarriedbytheflashedportionofthebreakflow,partitioningofiodinebetweentheliquidandsteamphases,themassoffluidreleasedfromthegeneratorandliquid-vaporpartitioningintheturbinecondenserhotwell.Alloftheseparameterswereconservativelyevaluatedforadesignbasisdoubleendedruptureofasingletube.A.'esinBasisAnalticalAssumtionsThemajor'assumptionsandparametersusedintheanalysisareitemizedinTable111.1.Thefollowingisadiscussionofthesourceterm.SourceTermCalculationsTheradionuclideconcentrationsintheprimaryandsecondarysystem,priortoandfollowingtheSGTRaredeterminedasfollows:a.Theiodineconcentrationsinthereactorcoolantwillbebaseduponpreaccidentandaccidentinitiatediodinespikes.1074v:1D/11208743 MESTINGHOUSEPROPRIETARYCLASS2AccidentInitiatedSpike-Theinitialprimarycoolantiodineconcentrationis1yCi/gmofDoseEquivalent(D.E.)I-131.FollowingtheprimarysystemdepressurizationassociatedwiththeSGTR,aniodinespikeisinitiatedintheprimarysystemwhichincreasestheiodinereleaseratefromthefueltothecoolanttoavalue500timesgreaterthanthereleaseratecorrespondingtotheinitialprimarysystemiodineconcentration.Thedurationofthespike,[3.31'ours,issufficienttoincreasetheinitialRCSI-131inventorybyafactorof[100]'ii.PreaccidentSpike-AreactortransienthasoccuredpriortotheSGTRandhasraisedtheprimarycoolantiodineconcentrationfrom1to60yCi/gramofD.E.I-131.b.Theinitialsecondarycoolantiodineconcentrationis0.1yCi/gramofD.E.I-131.c.Thechemicalformofiodineintheprimaryandsecondarycoolantisassumedtobeelemental.4DoseCalculationsThefollowingassumptionsandparameterswereusedtocalculatetheactivityreleasedtotheatmosphereandtheoffsitedosesfollowingaSGTR.1.ThemassofreactorcoolantdischargedintothesecondarysystemthroughtheruptureandthemassofsteamreleasedfromtheintactandrupturedsteamgeneratorstotheatmospherearepresentedinTableII.5andII.G.2.ThetimedependentfractionofruptureflowthatflashestosteamandisimmediatelyreleasedtotheenvironmentispresentedinFigureIII.1.3.Thetimedependentiodineremovalefficiencyforscrubbingofsteambubblesas'heyrisefromtheleaksite[(assumedtobeatthetopofthetubebundle)]'othewatersurfacewasalsodeterminedforeach,1074v:10/112087 MESTINGHOUSEPROPRIETARYCLASS2case.,Theiodineremovalefficiencyisdeterminedbythe.methodsuggestedbyPostmaandTam(Ref.6).TheiodineremovalefficienciesareshowninFigureIII.2.4.The0.2gpmprimarytosecondaryleakisassumedtobesplitevenlybetweenthesteamgenerators.5.Theiodinepartitionfactorbetweentheliquidandsteamoftherupturedandintactsteamgeneratorsisassumedtobe1DO.6.Nocredit'astakenforradioactivedecayduringreleaseandtransport,orforclouddepletionbygrounddepositionduringtransporttothesiteboundaryorouterboundaryofthelowpopulationzone.7.Short-termatmosphericdispersionfactors(x/gs)foraccidentanalysisandbreathingratesareprovidedinTableIII.4.ThebreathingrateswereobtainedfromNRCRegulatoryGuide1.4,(Ref.4).OffsiteThroidDoseCalculationModelOffsitethyroiddosesarecalculatedusingthe~uation:ThgtDCF,.g(IAR);.(BR).(x/()).]1Jwhere(IAR)..=integratedactivityofisotopeireleasedduring'the1Jtimeintervalj'nCi>>F*Nocreditistakenforclouddepletionbygrounddepositionorbyradioactivedecayduringtransporttotheexclusionareaboundaryortotheouterboundaryofthelow-populationzone.1074v:1D/11208745 WESTINGHOUSEPROPRIETARYCLASS2(BR)~breathingrateduringtimeinterval'inmeter/second(TableIII.4)(x/Q)=atmosphericdispersionfactorduringtimeintervaljJinsecond/meter(TableIII.4)(DCF).=thyroiddoseconversionfactorviainhalationfor1isotopeiinrem/Ci(TableIII.5)thyroiddoseviainhalationinremResultsThyroiddosesattheExclusionAreaBoundaryandLowPopulationZonearepresentedinTableIII.6.AlldosesarewellwithintheallowableguidelinesasspecifiedbyStandardReviewPlan15.6e3and10CFR100.1074v:1D/11248746 WESTINGHOUSEPROPRIETARYCLASS2TABLEIII.1PARAMETERSUSEDINEVALUATINGTHERADIOLOGICALCONSEQUENCESOFASTEAMGENERATORTUBERUPTUREI.SourceDataA.Corepowerlevel,MWt1520B.Totalsteamgeneratortubeleakage,priortoaccident,gpm0.2C.Reactorcoolantiodineactivity:1.AccidentInitiatedSpikeTheinitialRCiodineactivitiesbasedon1I>Ci/gramofD.E.I-131arepresentedinTableIII.3.TheiodineappearanceratesassumedfortheaccidentinitiatedspikearepresentedinTableIII.2.2,Pre-AccidentSpikePrimarycoolantiodineactivitiesbasedon60gCi/gramofD.E.I-131arepresentedinTableIII.3.,D.SecondarysysteminitialactivityDoseequivalentof0.1yCi/gmofI-131,presentedinTableIII.3.1074v:1D/11208747 HESTINGHOUSEPROPRIETARYCLASS2TABLEIII.l(Sheet2)E.Reactorcoolantmass,gramsF.Steamgeneratormass(each),grams1.27x103.39x10G.Offsitepow'erLostattimeofreactortripH.Primary-to-secondaryleakagedurationforintactSG,hrs.I.Speciesofiodine100percentelementalII.ActivityReleaseDataA.Faultedsteamgenerator1.Ruptureflow2.RuptureflowflashingfractionSeeTableII.5orII.GSeeFigureIII.13.IodinescrubbingplusmoistureseparatorremovalefficiencySeeFigureIII.24.Totalsteamrelease,lbsSeeTableII.5orII.G5.Iodinepartitionfactora.Priortooverfillb.Afteroverfill100-1.0-SeeFigureIII.36.Locationoftuberupture[TopofBundle]'074v:10/1120S748 MESTINGHOUSE.PROPRIETARYCLASS2TABLEIII.1(Sheet3)B.Intactsteamgenerator1.Primary-to-secondaryleakage,gpm0.12.Totalsteamrelease,lbsSeeTable11.5or11.63.Iodinepartitionfactor100C.Condenser1.Iodinepartitionfactor100D.AtmosphericOispersionFactorsSeeTableIII,41074v:lo/11208749 MESTINGHOUSEPROPRIETARYCLASS2TABLEIII.2IODINESPIKEAPPEARANCERATES(CURIES/SECOND)1-1323-133I"1340.942.221.743.071074v:1D/11208750 MESTINGHOUSEPROPRIETARYCLASS2TABLEIII.3IODINESPECIFICACTIVITIESIN(yCi/gm)THEPRIMARYANDSECONDARYCOOLANTBASEDON1,60AND0.1yCi/gramOFD.E.I-131Nuclide~Pit11~luCD/m60uCi/cDmSecondarCoolant0,1wCi/(1m0.7947.10.079I-1320.3520.70.0351.0160.70.1010.2012.20.020I-1350.7947.10.0791074v:1D/11208751 MESTINGHOUSEPROPRIETARYCLASS2TABLEIII.4ATMOSPHERICDISPERSIONFACTORSANDBREATHINGRATESTimeExclusionAreaBoundaryLowPopulation(hours)x/Q(Sec/m)3Zonex/Q(Sec/m)3BreathingRate(m/Sec)[4]0-22-84.8x103x103x103.47x103.47x101074v:1D/11208752 WESTINGHOUSEPROPRIETARYCLASS2TABLEIII.5THYROIDDOSECONVERSIONFACTORS(Rem/Curie)[51Nuclide~I-131I-1341.49x101.43x102.69x103.73x105.60x101074v:1D/11208753 NESTINGHOUSEPROPRIETARYCLASS2TABLEIII.6RESULTSOosesRemAllowableCase1Case2GuidelineValuel.AccidentInitiatedIodineSikeExclusionAreaBoundary(0-2hr.)Thyroid26.43.830LowPopulationZone(0-8hr.)Thyroid1.70.3302.Pre-AccidentIodineSikeExclusionAreaBoundary(0-2hr.)Thyroid102.122.1300,LowPopulationZone(0-8hr.)Thyroid6.41.4300~1074v:1D/11248754 WESTINGHOUSEPROPRIETARYCLASS2GINN4SGTRIS%TUBEPLUGGING-C4SER4OIOLOGIC4LCONSEOUENCESEV4LU4TIONBREAKFLOWFL4SNINGFR4CTION~ISCase1e.~It~Si,tt&~tt~S4,lt~SiTIICItttlGINN4SGTRISZTUBEPLUGGINGCASE2R4OIGLOOICALCONSEOUENCESEVALUATIONBREAKFLOWFLASHINGFR4CTION~ISCase2~ItH,tt14~StSI,ateiTletItttIFigureIII.1BreakFlowFlashingFraction1074v:1D/11208755 HESTINGHOUSEPROPRIETARYCLASS2GL,GCASE1o5~2081eeeTINE(SECONDS)1588288~5CASE24Z.(~2VM'I01088TINEISECONDSI1508288FigureIII.2SrubbingEfficiency1074v:1D/112087 WESTINGHOUSEPROPRIETARYCLASS2IE+2CASE11E+120~aC<LE+8ZIHE(HOURS)1.5JE+2CASE21E+120CC+IE+8TIHE(HOURS)FigureIII.3FaultedSGIodinePartitionFactors1074v:1D/11208757 WESTINGHOUSEPROPRIETARYCLASS2IV.CONCLUSIONThepotentialradiologicalconsequencesofasteamgeneratortubefailurewereevaluatedfortheR.E.GinnanuclearpowerplanttodemonstratethattheuseoftheStandardTechnicalSpecification(STS)primarycoolantactivitylimitof1yCi/gramofdoseequivalentI-131willresult.inoffsitedosesthatarewithintheappropriateguidelines,ThemassreleasesforadesignbasisdoubleendedruptureofasingletubewithalossofoffsitepowerwereconservativelycalculatedusingthecomputercodeLOFTTR2.Twocaseswereconsidered:[1)intactsteamgeneratorPORVfailsclosedandmustbelocally1opened,and2)rupturedsteamgeneratorPORVfailsopenandmustbelocallyisolated.]'heanalysisexplicitlymodeledthetimeneededforthe'peratorstoperformtherecoverystepsoutlinedinguidelineE-3ofRevision1oftheWestinghouseOwnersGroupEmergencyResponseGuidelines.TheresultingdosesattheexclusionareaboundaryandlowpopulationzonearewithintheallowableguidelinesasspecifiedbyStandardReviewPlan15.6.3andlOCFR100.Consequently,theSTSprimarycoolantactivitylimitissufficientlylowtoensurethattheradiologicalconsequencesofasteamgeneratortuberuptureattheR.E,Ginnaplantwillbewithintheguidelines.1074v:1D/11208758 HESTINGHOUSEPROPRIETARYCLASS2V.REFERENCES1.Lewis,Huang,Behnke,Fittante,Gelman,"SGTRAnalysisMethodologytoDeterminetheMargintoSteamGeneratorOverfill,"HCAP-10698-P-A,August1987.[PROPRIETARY'.Lewis,Huang,Rubin,"EvaluationofOffsiteRadiationDosesforaSteamGeneratorTubeRuptureAccident,"Supplement1toHCAP-10698-P-A,March1986.[PROPRIETARY]3.R.Elaisz,LetterfromRGEtoHestinghouseconcerningGinnaspecificoperatoractiontimesforSGTRanalysis,February7,1985.4.NRCRegulatoryGuide1.4,Rev.2,"AssumptionsUsedforEvaluatingthePotentialRadiologicalConsequencesofaLOCAforPressurizedHaterReactors",Jun'e1974.5.NRCRegulatoryGuide1.109,Rev.1,"CalculationofAnnualDosestoManFromRoutine,ReleasesofReactorEffluentsforthePurposeofEvaluatingCompliancewith10CFRPart50AppendixI",October1977.6.Postma,A.K.,Tam,P.S.,"IodineBehaviorinaPHRCoolingSystemFollowingaPostulatedSteamGeneratorTubeRupture",NUREG-0409.1074v:1D/12048759 IraV0;Jih

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