ML18031A407

Addendum to Final Rept Independent Design Review- Susquehanna Steam Electric Station.

ML18031A407
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Site:	Susquehanna
Issue date:	10/27/1982
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TR-5599-3-ADD, NUDOCS 8211010072
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'F~~:"-~~.-'."="-~m=.-~~-8TELEDYNEEMQIMEERIMQSERVICESTR-5599-0ADDENDUMTOFINALREPORTINDEPENDENTDESIGNREVIEWSUSQUEHANNASTEAMELECTRICSTATIONOCTOBER27,198282iiOi007282i027PDRADOCKOS0003871PPDR PENNSYLVANIAPOWERANDLIGHTCOMPANYTWONORTHNINTHSTREETALLENTOWN,PENNSYLVANIA18101TECHNICALREPORTTR-5599-3ADDENDUMTOFINALREPORTINDEPENDENTDESIGNREVIEWSUSQUEHANNASTEAMELECTRICSTATIONOCTOBER27,1982'PC'TELEDYNEENGINEERINGSERVICES130SECONDAVENUEWALTHAM,MASSACHUSETTS02254617-8Rh3350 TechnicalReportTR-5599-4wTELEDYNEENGINEERINQSERVtCESTABLEOFCONTENTS

1.0INTRODUCTION

2.0CLOSINGOFFINDINGS2.1FindingNumber12.2FindingNumber23.0ANCHORRECONCILIATION,PROGRAM3.1Definitionof'Anchor3.2ProgramDivision3.3ProgramDetails4.0PROGRAMMONITORING

5.0CONCLUSION

S6.-0REFERENCES~Pae6APPENDICES1-TESLetterNumber5599-172-As-BuiltReconciliationProgramReviewObjectivesandProceduresManual s>TELEGYNEENQINEERlNQSERVICESTechnicalReportTR-5599-

41.0INTRODUCTION

Thisreportissubmittedtoservetwopurposes.ThefirstistocloseoutthetwofindingsdefinedintheTESFinalReportNumberTR-5599-3datedAugust22,1982(Reference1).ThesecondistoactasanExecutiveSum-marytotheIndependentDesignReviewperformedbyTESontheSusquehannaSteamElectricStation.2.0CLOSINGOFFINDINGSThe~followingdiscussionpresentsthedetailsbehindtheclosingofFindingsbyTES.2.1FindinNumber1ThisFindingwasclosedbyLetterNumber5599-17,datedOctober19,1982,whichisattachedinAppendix1.ThebasisofFindingNumber1wasthattheDesignSpecificationcategorizationofplantoperatingconditionswasnotproper.InBechtelDesignSpecification8856-M-175,Revision5,thetransientcondition"LossofFeedwaterPumps,MainSteamIsolationValvesClosed"isclassifiedasanEmergencyCondition.BasedontherequirementsofASME,BPVCSectionIII(Code)thisclassificationprecludesthiseventfromconsiderationinthefatigueevaluation.However,theCode.inParagraphNB-3113.3requiresthataneventclassifiedasanEmergencyCondition:"shallnotcausemorethan25stresscycleshavinganSavaluegreaterthanthatfor10cyclesfromtheappli-cablefatiguedesigncurvesofFiguresI-9.0."

-s>-TELEDYNEENGINEERINGSERVICESTechnicalReportTR-5599-4Thisevent,"LossofFWPumpsMSIVClosed"isspecifiedasoccurringtentimes.Foreachoccurrence,th'reestepchangesintemperaturefrom546Fto40Fandonestepchangeintemperaturefrom546Fto100Fisspecified.Additionallyrecoveryfrom40Fto546Fatvarioustimesisalsospecified.Basedonthespecifiedconditions,morethan25stresscycleshavinganSvaluegreaterthanthatfor10cyclesfromtheapplicablefatiguecurveswilloccur.Thiseventwillhaveasignificantimpactonthefatiguelifeofcomponentsandmustbeconsideredinthefatigueevaluation.ThiscanonlybeaccomplishedbyclassifyingtheeventasanUpsetCondition.TheinformationsubmittedbyBechtelinReference3addressedtheimpactofthe"LossofFeedwaterPumps,MSIVClosed"transientontheFatigueUsageFactorfortheMainFeedwaterSystem.Further,astudywasdonethatdeterminedthefatigueeffectonallotherClass1systemswasnegligible.Asummaryofthatinformationfollows:~SstemFeedwaterCoreSprayRPVDrainStandbyLiquidControlRCICHPCIHeadVentHeadSprayMSIVDrainFactor~Stud0.94940.89850.35760.43830.61510.82950.60270.79570.03930.89930.89750.35760.43320.61460.82900.60210.79560.0384~U~5<<RItisimportanttounderstandthattheTESpositiononthisFind-inghasalwaysbeenthatasafetyconcerndidnotexist.Infact,TESpointedoutattwoNRCstaffmeetingsthatourexperienceinanalyzing w-TELEDYNEENGINEERINGSERVtCESTechnicalReportTR-5599-4Class1BWRsystemsindicatedthattherequirementsoftheASME,BPVCSectionIIIwouldbemetconsideringthiseventasanUpsetOperatingCondition.TESneededdocumentationfromBechtelverifyingthisposition.ThathasbeensubmittedinReference3.FindingNumber1hasbeenaddressedtothesatisfactionofTESandisthereforerevisedtoanObservation.2.2FindinNumber2ThisFindingisrelatedtothereconciliationprocessofas-builtsupportsandresultsfromthefactthatfurthercalculationswererequiredbyBechteltoresolveas-builtgeometriesfortheMainFeedwaterSystem.ThefollowingisasummaryoftheFindingasdetailedinReferencel.FindingNumber2(Phase1FindingNumbers7,9and10,andObser-vationNumbers3,4,5,6,7and9)Asignificantnumberofcommentshavebeengeneratedonthesup-portdesignprocess.Mostofthesecommentsarerelatedtoreconciliationofas-builtgeometrybythesupportdesigner.Theconcernisbasicallyassociatedwithacceptabilityoftheas-builtsupport.Twomajoritems(FindingNos.7and10)havebeenrespondedtobyBechtelinthisPhase2portionofthereviewbuttheyonlytendtosupportthattheprocessdidnotwork.TheresponsetoPhase1FindingNo.7indicatesthatthepipesupportreviewerandcheckerdeterminewhetherarelocatedsupportwasasignificantenoughchangetowarrantaCivildepartmentreview.InthecaseofthespecificsupportofconcernnoCivilreviewisapparent.How-ever,thereisanewplaterequiredintheas-builtdesignwhichisthe I~A~pgLEENQ!NEERlNQSERVCESTechnicalReportTR-5599-4responsibilityoftheCivildepartment.Thesupportdesigngroupcalcula-tionsindicatethattheplatewillbehandledbytheCivilgroupandtheCivilcalculationsdonotaddresstheplatesincetheydonotknowthesupportislocatedonitwithouthavingtheas-builtgeometryforwardedtothem."InthefinalBechtelsubmittaltheplatehasbeenanalyzedbytheCivildepartmentasaresultoftheTESfindings.TheresponsetoPhase1FindingNo.10indicatesthattheweldattheshieldwallisacceptableafterreducingtheconservatismintheorig-inalanalysisandperformingadetailedcomputersolutionofthesupport.ItisapparentthatthisweldwasnotaceptablebyinspectionasoriginallystatedbyBechtel.ResponsestoFindingNumber9andtheObservationslistedunderthisFindingwerereviewedandinsomecasesindicate,theObservationcouldhavebeenclosedifsufficientdetailwasprovidedintheBechtelrecon-ciliationprocess.DuringtheAugust10,1982meetingatTES,Bechtelindicatedthatgroupmeetingsandtrainingsessionswereheldtoexplainproceduresusedinthereconciliationprocess.Further,thereviewercheckseachitemanddeterminesacceptabilityandevencrosseseachitemoffthathejudgesisacceptableonacheckprint.Noneofthisinfor-mationisretainedbyBechtelnoristhereanyrecordmaintainedofmeetingsortrainingsessionsforthispurpose.IInresponsetothisFinding,PPELundertookareviewofthereconciliationprocessforanadditional20supportsonsystemsotherthanthefeedwatersystem.Thatreviewindicatedthatoneanchorwouldrequireextensivereanalysis.Essentially,theas-builtanchorhadapproximatelyone-fourthoftheas-designedweldlength.Asaresultofthis,PPKLelectedtogotoasampleof400supports.Thebreakdownofthatsampleisasfollows:

AEENQlNEERINQSERVICESTechnicalReportTR-5599-4ComositionofSamleTe~P1i~5SnubbersSpringsRigidSupportsAnchors25K15K54K6X100K11%3X75K11%100KThesampleconcentratedmoreheavilyonrigidsupportsandanchorsbecausetheIDRFindingandtheoriginalPPKLsampleihdicatedthatthesewerethemostcriticaltypesupportswithrespecttoreconciliation.Adetailedprocedureforthereviewofthe400supportswasdevelopedbyPPKLandreviewedbyTES.AcopyofthatprocedureisattachedinAppendix2.ATESobserverwaspresentattheBechtelofficesinSanFranciscoduringthemajorpartofthisreviewrelatedtoCategori-zation.Ourobservationofthatprocessincludedspot-checkingofsupportstodetermineifTESagreedwiththecategorization.TESconcludedthattheprocessasdefinedbyPPKLandreviewedbyTESwasbeingcarriedoutsuc-cessfullyandthatthepersonnelinvolvedinCategorizationwereallowedtoreachdecisionsindependently.Basedonthis,TESdeterminedthatareviewofallCategoryIIIsupportswouldbesufficienttoreachourconclusion.Ourreviewof80supportsdesignatedasCategoryIIIresultsinthefollow-ing:1.Theoriginalreconciliationprocessindicatesweaknessesintheareaofacceptanceofas-builtdesigns.Thisispri-marilyyrelatedtothosesupportsthatwerereconciledbasedonengineer',ngjudgment.Thisisbasedonthefactthat14supportsrequiredextensivereanalysistodetermineadequacyand40supportsrequiredsomesimplerecalculation.Extensiveanalysisincludesdetailcomputeranalysisofthe ATELEDYNEENQINEERIMQSERVlCESTechnicalReportTR-5599-4supportand/orreanalysisofthepipingsystemtoreduceloadingconservatisms.2.Thecategorizationof89itemsinCategoryIIIwasverycon-servative.ItisTES'pinionthatapproximatelyone-halfofthesesupportsshouldhavebeenCategoryII.3.AllsupportsotherthananchorshavebeendemonstratedtobeadequatebythePPELreviewandtheBechtelresponses,includingreanalysis.TEShassufficientevidencetoremovethesefromfurtherconsideration.4.Areconciliationproblemrelatedtoweldcapacitystillexistsforanchors.AprogramacceptabletoTEShasbeenpresentedinSection3.0.AcceptanceofthisprogrambyPP8LwouldsatisfyFindingNumber2oftheIDR;3.0ANCHORRECONCILIATIONPROGRAMInorderforTEStoremoveFindingNumber2,thefollowingpro-grammustbeacceptedbyPPSL.3.1DefinitionofAnchorAnanchorisdefinedasanysupportthatprovidesrotationalaswellastranslationalrestrainttothepipingsystem.Onedirectionofrotationalrestraintissufficientforasupporttobecategorizedasananchor.Anchorswhicharepartofcontainment(fluedheads)aridanchorsatequipment(pumps,vessels,etc.)arespecificallyexcludedfromthispro-gram.Essentially,thisprogramislimitedtointermediateanchorswhichusestructuralsteeltoproviderestraint.

TechnicalReportTR-5599-4><TELEDYNEENQINEERINQSERVICES3.2ProramDivisionTheprogramshouldbedividedintotwophases,asfollows:1.Phase1-anchorsinsidecontainment.2.Phase2-anchorsoutsidecontainment.ThereasonforthisdivisionisthatTESfeelstheplantshouldbeallowedtooperateoncetheanchorsinsidecontainmenthavebeenreconciled.Thisisbecausetheearthquakeevent(OBEorSSE)isasignificantloadforallanchorsand,fortheshorttimeneededtoreconcileanchorsoutsidecon-tainment,theeventprobabilityshouldbeverylow.3.3~33Allanchorsshal)besubjectedtothecategorizationprocessdefinedinAppendix2.ThoseanchorswhichareplacedinCategoryIand/orIIwillbeacceptablebydefinition.ForthoseanchorsplacedinCat-egoryIIIonlyanalysiscomparabletotheas-designedanalysisisallowableforreconciliation.Ifreconciliationcannotbereachedinthismannertheanchorwillbemodifiedtoreflectas-designed.Whereinterferenceoraccessdoesnotpermitthisapproach,modificationstotheanchormaybemadewhichdonotreflectas-designedbutdoprovidethesamedesignmargin.Itisnotedthatanalysistechniquesbeyondthoseusedintheoriginalanchordesignarenottobeusedtoprovidethedesignmargin.4.0PROGRAMMONITORINGTES'eviewoftheimplementationofthePP8Lprogramforrecon-ciliationnofthe400supportsamplewasquiteextensive.Basedonthis

-<>-TELEDYNEENQINEERINQSERVICESTechnicalReportTR-5599-4review,ourconfidenceinthePP&LpersonnelinvolvedandPP&L'scommitmenttothisprogram,wefeelthereisnofurtherneedforTESparticipation.

5.0CONCLUSION

STheIndependentDesignReviewperformedontheMainFeedwatersystemattheSusquehannaSteamElectricStationwasquiteextensiveinscope.ThisreviewprovidedTESwithadetailedunderstandingofthefollowing:5.1FSARcommitments,5.2gualityAssuranceprocedures,processandimplementation,5.3Designprocedures,processandimplementation,5.4As-builtconfiguration,5.5Reconciliationofas-builtgeometriesversusas-designed,and5.6ImplementationofFSARcommitments.Based'ontheresultsofourIndependentDesignReview,itisTES'pinionthat,uponcompletionoftheprogramoutlinedinSection3.0ofthisreport,thecommitmentsoftheFSARhavebeencompliedwithfortheSusquehannaSteamElectricStation.6.0REFERENCES6.1TESFinalReportTR-5599-3,"IndependentDesignReview-SusquehannaSteamElectricStation",datedAugust23,1982.6.2PP&LLetterNumberER100450,PLA-1328,datedOctober4,1982,fromN.W.Curtis(PP&L)toA.Schwencer(USNRC).6.3BechtelLetterNumber0176565,datedSeptember24,1982,fromE.B.Poser(Bechtel)toR.Enos(TES).

TechnicalReportTR-5599-4ATELEDYNEENQINEERtNQSERVlCES(APPENDIX1TESLETTERNlNBER5599-17 ATElEDYNEENGINEERlNGSERVlCES130SECONDAVENUEWAOHAM,MASSACHUSETfS02254(617)6903350IWX(710)324.7580October19,19825599-17Mr.RobertJ.ShovlinAssistantProjectDirector-SusquehannaPennsylvaniaPowerandLightCompanyTwoNorthNinthStreetAllentown,Pennsylvania18101~Sub'ect:TESIndependentDesignReview-SusquehannaSteamElectricGeneratingStation

References:

(1)PPSLLetterER100450datedOctober4,1982(2)BechtelresponsetoPhase2,FindingNo.1(Identifi-cationNo.0176565)datedSeptember24,1982

DearMr.Shovlin:

Attachedaresixcopiesofthisletter.Wehavealsoforwardedcopiestothefollowingpartiesinaccordancewithyourinstructions.Mr.A.SchwencerU.'S.NuclearRegulatoryCommission7920NorfolkAvenueBethesda,Maryland20014Mr.RobertPerch(ToBeOpenedbyAddresseeOnly)U.S.NuclearRegulatoryCommission7920NorfolkAvenueBethesda,Maryland20014Mr.J.B.Violette(4copies)BechtelPowerCorporationP.0.Box3965,"50BealeStreetSanFrancisco,California94119ThisletterissubmittedasapreliminaryreactiontoReferences(1)and(2)responsestoPhase2,FindingNo.1,oftheTESFinalReport.ThisitemwillbeaddressedingreaterdetailinanAddendumtotheTESFinalReport.ItisanticipatedthattheAddendumwillbesubmitteduponcom-pletionofareviewbyTESoftheSupportReconciliationReportbeingpreparedbyPPSLinresponsetoPhase2,FindingNo.2.ThebasisofFindingNo.1isthattheDesignSpeci'ficationcategorizationofplantoperatingconditionsisnotproper.Thisisspecificallyrelatedto"LossofFeedwaterPumps,MSIVClosed"beingclassifiedasanFNGINFFRSANOfi';""TALLURGISTS Mr.Shovlin,PPKL5599-17October19,1982Page2PsTELEDYNEENGINEERINQSERVICESEmergencyCondition.References(1)and(2)indicatethattheinclusionofthistransientintheUpsetConditioncategorydoesnotviolateCodefatiguecriteria.Further,astudyofothersystemsindicatesthatthistransientislesssevereandwouldhavenegligibleeffectonfatigueusagefactorsforthosesystems.TEShasstatedattwomeetingswiththeNRCstaffthatourexperienceinanalyzingBMRpipingsystemsindicatesthattheresultsobtainedbyBechtelcouldbeexpectedandnosafetyconcernsexisted.Basedonthisknowledge,TESrequestedthatsufficientdocumentationbepresentedtoindicatethatBechtelreachesthesameconclusionwhenthistransientisconsideredasanUpsetCondition.ThisdocumentationwaspresentedinReference(2).ItisapparentthatthedefinitionofFindingasusedbyTESintheIDRofSusquehannaisbeingmisunderstood.AFindingdoesnotnecessarilymeanthatasafetyconcernexists.TESfeelsthatanyconcernsresultingfromPhase2,FindingNo.1,withrespect.tosafetyshouldbeeliminated.Basedontheabove,Phase2,FindingNo.1,shouldbechangedtoanObservationthathasbeensufficientlyaddressedbyPPKL.Ifyouhaveanyquestionsconcerningthispleasedonothesitatetocontactme.Verytrulyyours,TELEDYNEENGINEERINGSERVICESdgt.Lados,DonaldF.LandersSeniorVice-PresidentDFL/lhcc:R.A.Enos(TES)D.Messinger(TES)TESDocumentControl dIl TechnicalReportTR-5599-4<>TELEDYNEENQtNEERIMQSERVrCESAPPENDIX2AS-BUILTRECONCILIATIONPROGRAMREVIEWOBJECTIVESANDPROCEDURESMANUAL Revision010/9/82Revision1IO/9/82I(Q<~Revision210/12/82AR-BUILTRECONCILIATIONPROGRAMREVIEWOBJECTIVESANDPROCEDURESMANUALSUSQUEHANNASTEAMELECT1GCSTATIONPENNSYLVANIAPCNER&LIGHTCOMPANYR.~NP23/1-1N..Rhoades-P.P.EL.

Page2IHIROIX3CTIONIthasbeenconcludedbyPP&LthatadditionalreviewoftheAs-BuiltReconciliationProgramisnecessary.'IhepurposeofthisreviewistoprovideaveryhighconfidenceleveltoPP&LandtheNRCthatthereexistnounsafepipingsupportsintheSusquehannaSteamElectricStation.Accordingly,PP&Lhasselectedasamplesizeoffivehundred(500)seismiccategoryonesupportstobereviewed.Thissamplesizeprovidesuswiththehighdegreeofconfidencewerequire.However,afterwehavereviewedseveralhundredsupports,thissamplesizemaybeadjustedupwardsordownwardsdependingontheresultsofthesurveyatthattime.SelectionofthesupportstobereviewedwillbemadebyPP&Lrepresentatives.Itisintendedthatthesampleselectedberandomwithrespecttosystemsbutskewedinfavorofanchors,rigidandoperationallyactivesnubberswithlessconsiderationtowardsdeadweighttypesupports.Acanpletelistofthosesupportsselectedwillbedocunentedinthefinalreport.WP23/1-2 r

Page3DEFINITIONSThefollowingarethedefinitionsofthecategoriesofdifferencesbetweentheas-builtandengineeringdrawings.CAHKORYI:Arethosedifferenceswhichareconsideredinsignifi-cant,suchasslightvariationindimensions.CATEGORYII:Arethosedifferenceswhichmaybeofconcernbutuponfurtherinvestigationareconsideredacceptable.Theinvestigation,however,maybebyengineeringjudgementorbysimplyreferringtotheasMesignedcalculationandnotingwhattherequirementsoractualstressesare.CATEGORYIII:Arethosedifferenceswhichareofconcernandrequirefurtherevaluation.Theevaluationwouldrequireanadditionalanalysisor,amoredetailedanalysisoftheoriginalcalculation.REJECT:RejectisdefinedbyPP&Lasanysupportthat,inthejudgementofPP&L,requiresafieldhardwaremodification.WP23/1-3 Page4ORGANIZATIONThisprogramisorganizedintothreeprimarytaskgroupsplusadocunentationretrievalgroup.Taskgrouponewillperformthefunctionofcanparingandclearlyidentifyingalldifferencesbetweenthefinal"as-built"andtheengineeringanalyzedsupportdrawing.Grouptwowillperformthejudgementsanddeterminetowhichcategoryeachitem,highlightedbyGroupone,istobeputanddocumentthatcategory.GroupthreewilltakethoseCategoryIIIwhichrequireresolutionandperformthenecessarycalculationsoradditionalresearchworktoverifyacceptabilityofthesupport.IffieldwalkdownforreviewofspecificsupportisrequireditwillbemadeanddocumentedbythePP&LResidentEngineering.DOCUMENTATIONRETRIEVALSTEPS-1.Check'PipeSupportlistagainstDOCRETtonotethelatestEngineeringrevision.(DOCRETisthelogofengineeringrevi-sionsissuedandisgeneratedfranmicrofilmcardsandwasinexistenceatthetimeofas-builtreconciliation.)W'23/l-4 Page52.CbpyofEngineeringrevisiona.Retrievecopyb.Make1copyc.'Xbbefiledinbinderlater3.Cbpyofthelatestas-builtfromtheABR(As-BuiltReconciliation)bindera.Checkrevisioninbinderreconciliationsheetb.Iacateas-builtP.S.detailintheABR.Checktoensurethatthestickerissigned-offbyEngineering.c.PutmarkerintheABRbinderd.Sign-outoutcarde.Make1copyf.Filebackwheremarkerwasg.Sign-outABRout-card.CanrisonofEnineeriandAs-BuiltPiSurtDetails(Yellow-outProcess):1.CbtaincopyofEngineeringandas-builtP.S.revision2.Yellow-outallitemsthatareidenticalonbothEngineeringandas-builtpipesupportdetail.3.ItemsnotidenticaltotheEngineeringrevisionshouldbecircledinred.m23/1-5 Page64.Identifyitensthatarenotidentifiedoneitherofthedrawingsbyat'ircleingreenwithanasteriskmark.ItistobeemphasizedthatnogudgenentsaretobemadebyGrouponepersonnelandthatalldifferences,nomatterhowtrivialtheymayappear,aretobemarkedinredorgreen.Thefollmringexampleisanillustrationofthisrequirment:EnqineerinqDrawi"AsBuilt"ThisitemistobemarkedinredonAs-BuiltdrawingBillofMaterialsEnqineering4w>3x6'-2""As-Built"4l4!3x~6'l"Wisitenistobemarkedinred5.Filloutthecoversheetcarpletely6.Packagecoversheet,Engineeringrevisionandyellowed-outas-builtP.S.detail.7.AllpackagesreturnedtogrouponetaskcoordinatorforPALreview.RP23/1-6 Page7GROUP2ReviewandDissitionofDifferencesBetweenEineeriandAs-Built~D'tBWiSl.EnsurethatGroupOneCoverSheethasbeenproperlysignedoffpriortoperforminganyreviews.2.Recordeachdifferenceontheprescribedsheet(attached).3.CategorizeeachdifferenceasCategoryI,II,IIIas-describedinDefinitionsSection.4.Besolutions:CategoryIdifferencesarethosethatareinsignificantsuchasslightvariationindimensionsandthus,areacceptablebydefinition.CategoryIIdifferencesarethosethatareacceptablebyengineeringjudgementorreferencetooriginalcalculations.Forexample,thedesigncalledfora6"diameterpipehavingawallthicknessof3/8".Theas-builtshowsa6"x6"x1/4"thicksquarestructuraltubeisusedinstead.Thismaybeacceptablebyengineeringjudgementbycanparingtheareaandsectionmodulesoftheminrelationtotheimposedload.Anotherexampleisthedesignhascalledfora3/8"filletweldallaroundamenber.Theas-builtshows5/16"filletweldisusedinstead.Byreferringtotheoriginalcalculation,itisnotedthata1/4"filletweldisrequiredandthusisacceptable.WP23/1-7 Page8(Mte:TheoriginalcalculationsareQAdocunentsand,assuch,areconsideredvalidandacceptabledesignbasiscalculations.Therefore,therewouldbenoneedtore-reviewtheoriginalcalculationsandwouldbebeyondthescopeofthistask).CategoryIIIdifferencesarethosethatrequireadditionalcalculationstoresolvethedifferencebetweentheas-designedandas-built.YoushouldsearchtheAs-BuiltReconciliation(ABR)booktoseeifthereexistcalculationsthataddresseachCategoryIIIdifference.WhentherearenoABRcalculationsforanitemorthecalculationsarenotsatisfactory,youshouldidentifythatadditionalcalculationsarerequiredpriortoacceptanceorsignoff.Pleaseprintyournameandyourteamleader'snameonthefirstsheetforidentificationpursespriortosubmittingthemtoyour.teamleader.Whenadditionalcalculationsarerequired,thenecessarycalculationswillbeperformedbyGroupIIIandprovided.toyou.Ifadditionalcal-culationsareneededtoresolvethedifference(s),nomatterhowsimpleacalculation,youarerequestednottomakethemyourself.Thisisbecauseoftwo(2)reasons.First,thethecalculationsneedtobeverifiedinaccordancewithestablishedproceduresandbedocunented.Second,theGroupIIIfunctionistomakethesecalculationsandtheyareavailabletodoso.AfteryouNP23/1-8 areprovidedwiththecalculationsthepackagewillbeconsideredcanpleteifyouconcurwiththecalculationsandallCategoryIIIdifferenceshavebeenaddressed.Ifnot,aresolutionforthemwillberequired.Ifthereisaninpass,PP&Lshalldeterminethefinalresolutionfor.them.Ifrejectsareidentified(seedefinition)becausehardwarechangesarerequiredtheywouldbeidentifiedandsignedoff.Needlesstosay,iftherearenoCategoryIIIdifferences,the"As-BuiltReconciliationJudgementVerification"formshallbesignedoffbasedonacceptanceofCategoryIandIIdifferences,ifany.5.ItemsthatneedFieldverificationorclarificationduetodrawing.ambiguity,clarityshouldbeidentifiedandbroughtto'I@amleader'sattentionforresolution.6.ForwardpackagetoPP&Lrepresentativeforreviewandconcurrence.GROUP3Perfonnanceof.AdditionalCalculationstoJustifAdeacoftheDifferencesDesinatedasCatoIIIGrouII1.GeneratecalculationsperPEWasnecessarytovalidatethedifferencesandtheas-builtconditiontotheextentfeasible.AllpackagesforwardedtoGroup3requireindividualizeddispositionWP23/1-9 Page10toassuresupportadequacy.Onceyoureceiveapackageidentifywhatmustbedone,notifyPP&Lofyourintendedaction,andproceed.Ifacalculationneedstoberun,proceedimnediatelyand,onceappropriatecalculationsareccmplete,attachthemtotheccmpletedpackage,signthecoversheetandfonmrdthemtoPP&L.Iffieldcheckingofanitemisrequired,notifyPP&LandtheywillmakearrangementsforPP&LResidentEngineeringgrouptomakenecessarychecks.Ifanysupportcannotberesolvedbyadditionalcalculations,notifyPP&Lirrrnediately.FINALDOCUMENTATICN:l.AsampleselectionoftheFinalDocunentationPackagewillbemadebyPP&Ltoassurethefollowing:a.As-BuiltReconciliationJudgementVerificationsheetcanletelyfilledin.b.Copiesofyellow-outcoversheetsfilledin.c.CopiesofEngineeringrevisionandas-builtP.S.detail(yellow-outcopy)d.Calculationsasapplicable,andwhengeneratedbyGroup3~foreachpipesupport.WP23/1-10 PagellLISTOFATTACHMENTS:1.SamplesignoffsheetforGroup12.SampleAs-BuiltReconciliationJudgementVerificationSignoffsheetforGroup2.WP23/1-l1 f'IlASWUILTRECONCILIATIONPROGRAMREVIEWHGRRNORCOMPARISONOFENGINEERINGANDASBUILTPIPESUPPORTDETAILYELLORtOUTPROCESS)PERFORMEDBYlPRINTNAMESIGNATUREDATEORGANIZATIONREVIEWPERFORIEO'YESSIGNATUREPP.<REVIEWEPBYl(IFYES)PRINTNAMESIGNATUREDATEORGANIZATION ASBUILTRECONCILIATIONJUDGMENTVERIFICATIONSUPPORTTYPESUPPORTINGoNOs!SOD46sNO>t':ENGGDING)REVeASBUILTREVeSYSTEMSHEET1OFPERFORMEDBYlSIGNPRINTREVIEWEDBY,'IGNPRINTFCICATEGORYIDIFFERENCESRESOLUTIONCATEGORYIDIFFERENCESAREDEPENDACCEPTABLEBYDEFINITIONI~I~~

ASBUILTRECONCILIATIONJUDGMENTVERIFICATIONSUPPORTDWGINOeSHEETOFiCATEGORYDIFFERENCESRESOLUTION 4llUMIAK-tCATRQQRY3K,RRSPQMSR~ABERCANC.RRQ.QYl6.MY.ASSU)LTQSV.ABRCALO.PsesrGMmseuiaan".ABSPQNSR:RRSPQNSKE'f.QuaAtwmnvseey ASBUILTRECONCILIATIONJVDGNENTVERIFICATIONSUPPORTIsaNOISHEETOFDIFFERENCESCATEGORYIIRESOLUTION4CATEGORYI,II I.Issuel.EffectsofLocalEncroachmentsonPoolSwellLoads2.SafetReliefValveDischareLineSleevesII.Assessment/ResonseTheNRCdispositionedtheseconcernsasN/AforSSES.III.FutureActionReuiredNone8211060230 I.Issue3.ECCSReliefValveDischareLinesBelowtheSuressionPoolLevel3.1Thedesignofthestudyplantdidnotconsiderventclearing,condensationoscillationandchuggingloadswhichmightbeproducedbytheactuationofthesereliefvalves.IIII.Assessment/ResonseInprefacetotheresponsetotheaboveconcern,itshouldbenotedthatthesteamcondensingmode(SCM)isan'operationallynon-safety-relatedsubsystemoftheRHRsystem.ItprovidesanoptionalmethodofremovingreactordecayheataftershutdownbycondensingreactorsteamintheRHRheatexchanger.Areliefvalveisprovidedtoprovideoverpressureprotectiontotheheatexchangerand,associatedpipingandcomponents.TheRHRSRVdischargesintothesuppressionpoolthrougha10"diameteropen-endedpipeatasubmergenceof4'elowlownormalwaterlevel.DuringpoweroperationtheRHRheatexchangerisisolatedfromthesteamsupplybytwoindependentandredundantsafety-gradeisolationvalves.Therefore,liftingoftheRHRSRVduetooverpressureisonlyassumedtooccurduringSCMoperation.Thesteamflowto,theRHRheatexchangers(Hxs)iscontrolledbytwoin-seriespressurecontrolvalves(PCVs),whichmaintainanoperatingpressureof200psigintheHxs.RHRSRVactuationoccursforthefollowingtwoscenarios:oBothPCVsfailopen.oFailedopenRHRSRV.Forthefirstcase,bothPCVsarecontrolledbythesamecontroller;thus,asinglefailureinthecontrollerleadstopossiblybothPCVsactuatingtothefullopenposition.Followingthefailure,thedownstreampipingpressurizestothereliefvalvesetpressureandopenstorelievepressure.SincetheRHRSRVsteamflowexceedstheflowcapacityofthetwocontrollers,thepressuredecreasesandtheRHRSRVquicklyreseats.OncetheRHRSRVrecloses,the6"VBsmountedontheRHRSRVDLopentoallowairintotheRHRSRVDL.ThepressureagainincreasesuntiltheRHRSRVliftstorelievepressurecausingamixtureofairandsteamtoflowintothepool.This"cycling"oftheSRVcontinuesuntiltheoperatorisolatestheSCMmode.Duringthistime,thesteamflowingthroughthePCVssimultaneouslycondensesintheRHRHxandflowsthroughtheRHRSRV.Furthermore,theRHRSRVcyclesrapidly,sothatthesteamflowneverreachessteady-stateconditions.Fortheabovereasons,theaveragesteamfluxintheRHRSRVDLismuchlowerthanthetheoreticalmaximumsteamfluxbasedontheratedflowthroughtheRHRSRVundersteady-stateconditions.

PivrIllII ThesecondscenariopostulatesafailureintheRHRSRVitself(i.e.,brokenspring)causingtheRHRSRVtofailwideopen.Undertheseconditions,thePCVwillmodulateopentoattempttomaintainadownstreampressureof200psig.However,thecontrollertothePCVselectronicallylimitsthePCVsto60%fullopen;thus,themaximumflowthroughthePCVswillbelessthantheratedflowofthePCVs.Again,understeady-stateconditions,theflowthroughthePCVsmatchestheflowtotheHxandRHRSRV.However,noSRVcyclingoccurs,sincetheRHRSRVfailedopen.Again,theRHRSRVsteamfluxismuchlowerthanthesteamfluxbasedontheratedflowthroughtheRHRSRVundersteady-stateconditions,sincethePCVslimittheflowandsteamcondensessimultaneouslyintheRHRHx.Forbothfailuremodes,theRHRSRVdischargessteamtothesuppressionpooluntiltheoperatorisolatesthesystem.WeassumetheoperatorwilldetectandisolatetheSCMsystem10minutesafterthefailureoccurswhichleadstoflowthroughtheRHRSRV.Operatoractionbasedon10-minutedelayisjustifiedsinceinstrumentationisavailabletodiagnosethesituationandtakeappropriatecorrectiveaction.OnceRHRSRVsteamflowbegins,theSuppressionPoolTemperatureMonitoringSystem(SPOTMOS)willalarmonhighpooltemperatureandprovideearlywarningofsteamdischargingtothepool.Inaddition,variousindicationsofSCMoperation,includingRHRHxlevelandpressure,areavailabletoindicatetotheoperatorthattheRHRSRVlifted.OurpreliminaryassessmentoftheeffectsoftheloadscausedbyactuationoftheRHR,,SRVfollows.Fromaglobalperspective,webelievetheexistingLOCAsteamcondensationandMSRVbuildingresponsesboundtheresponsesduetoanactuationoftheRHRSRV.Thatis,thebuildingmotioncausedbytheRHRSRVactuationwouldbemuchlessthaneither87ventpipeschugging,ortheresponsetothe16valveMSRVloadcase(referenceSSESDAR).Therefore,ourevaluationoftheRHRSRVloadswillbeconfinedtothemosthighlystressed(leastdesignmarginforcurrentdesignbasis)submergedstructuresandlinerplatead]acent;totheRHRSRVdischarge.OurevaluationconsistsofqualitativelycomparingtheoriginaldesignbasisandstressmarginsforthesubmergedstructuresandlinerplatewiththeexpectedloadsduetoRHRSRVactuationwhenconsideringtheappropriateloadcombinations.ThehydrodynamicloadsduetoRHRSRVdischargehavenotbeenspecificallycalculated,sincetheyareconsideredtobeboundedbytheexistingdesignbasis.However,weintendtoquantifytheloadsandprovidetheresultsofourassessmentbyMarch31,1983.AmoredetailedtaskdescriptionisgiveninSectionIIIofthisresponse.InordertocomparetheexpectedRHRSRVloadswiththecurrentdesignbasis,wemechanisticallydeterminedtheappropriateloadcombinationsfortheRHRSRVloads.Webelievetheloadcombinationtobeasfollows:

I'/V'V')V)II1(I' tRHRSRV+SSE+MSRV(lowsetpressure)',i1WeeliminatedtheLOCAloadsbasedonthefollowing.IfweassumeaLOCAoccursduringSCMoperation,coincidentwithafailureintheSCMsubsystemthatleadstoRHRSRVactuation,the.RHRSRVdischargeloadswillbeterminatedpriortothetimewhenthemostsevere'oadingsduetoaLOCAoccur.ThesteamsupplytotheSCMsubsystemautomaticallyisolatesviaaLOCAsignaltotwo,inseries,independentandredundantsafetygrade,airactuatedvalves.ThesevalvesfailclosewhentheLOCAsignalventsofftheairtothevalveactuator.Duringstartuptesting,theclosuretimesofthevalvesweremeasuredandindicatedaclosuretimeoflessthan15sec.BasedonourreviewofourGKMII-Mdatabase(seeSection9.0oftheSSESDAR),thehighamplitudechuggingandlateraltiploadsatthedowncomerexitoccurmorethan15secafterthebreak.(Aswillbeshownlater,forthesubmergedstructures,thelateraltiploadandchuggingsubmergedstructuredragloadgeneratethehigheststresses.)Atthistime,theSCMisolationvalveswillhaveterminatedthesteamflowtotheRHRSRV.Inaddition,post-LOCASCMoperationwillnormallynotoccur,unlessallothersafety-gradeECCSsystemsarenotavailableforremovingheatfromthereactor.Undertheseconditions,multiplefailureswillhaveoccurredintheECCSsystems,andassuch,thiseventgoesbeyondtheSSESdesignbasis.Thus,theRHRSRVloadswillnotbecombinedwithpost-LOCAhydrodynamicloads.Forthesamereasoning,theSRVADScaseneednotbecombinedwiththeRHRSRVload,sincetheSCMisolationvalveswillcloseduringthetwo-minutedelaycausedbytheADStimerpriortotheinitiationofADS.TheMSRVloadresultsfromtheSCM'sinabilitytoremoveallthedecayheatfromthereactorimmediatelyaftershutdown.IftheSCMoperatesimmediatelyaftershutdown,thelowsetpointMSRVswillcycletoremovetheexcessdecayheatuntilsometimeaftershutdownwhentheSCMaloneissufficienttoremoveallthereactordecayheat.WeassumeactuationoftheRHRSRVoccursduringthistimeperiod.ForSSES,thetwolowestsetpointMSRVs(1078psigsetpressure)dischargethroughquenchersE5Blocatedapproximately67'nd56.5',respectively,fromthepreviouslydescribedsubmergedstructuresadjacenttotheRHRSRVdischarge.Thus,fromthisdistance,weexpectthatthesubmergedstructureloadonthedowncomerand.bracingnearesttheRHRSRVdischargetobenegligible.SincethesesubmergedstructuresexperiencenegligibleloadingfromMSRVinertialloading(seeTables3.1and3.2),weexpectnegligibleloadingonthecriticaldowncomeranddowncomerbracingduetocyclingofthelowsetpointMSRVs.Inaddition,thesuctionloadonthelinerplateneartheRHRSRVdischargeduetothecyclingofthelowsetpointMSRVwillbemuchless4 r'1I thanthedesignbasissuctionload.ThequenchersE8Barelocatedatazimuthangles45'nd300',respectively,comparedtoanazimuthangleof180'orthelinerplateadjacenttotheRHRSRVdischarge.BasedontheonevalveMSRVloaddocumentedinSubsection4.1.3.2.1oftheDAR,thepeakunderpressuredecreasesasyoumoveazimuthallyawayfromthequenchers.Basedontheazimuthpressuredistributionfortheonevalvecase(seeDARFigure4-26),theunderpressurescausedbyafiringofeitherquenchersEorB(angles45'nd300')decreaseto0.2ofthemaximumunderpressureatthequencherlocationsatthe180'zimuthanglelocationfortheRHRSRVdischarge.Thus,thesuctionpressureduetoquenchersEandBfiringresultinlowerloadsatthelinerplateadjacenttotheRHRSRVdischarge.Basedontheabove,theloadsduetotheactuationofthelowsetpointMSRVsresultinnegligibleincreaseinthesubmergedstructureloadandlinerplatesuctionpressure,whencombinedwiththeRHRSRV+SSEloads.WecombinetheSSEloadsbasedonpreviousdesigncriteria.TheonlysubmergedstructuresclosetotheRHRSRVdischargearetheneighboringdowncomerandassociatedbracingandthelinerplate.OurcurrentdesignmarginsforthesesubmergedstructurestobecombinedwiththeRHRSRVloadsareasfollows:DowncomerTable3.1providesthestresscomponentsin%ofthetotalstressforthevariousloads,andthestressmarginforthecombinationofSSE+SRV(ADS)+LOCA.Asindicated,thestressmarginis53%,withSSEandLOCAlateraltiploadcontributingthemoststresses.TheSSEconsistsmostlyofthesubmergedstructureloadduetoseismicslosh(seeSubsection4.2.4.7oftheDAR).Theinertialloadsforallthreedynamicloadsareminimal,sincedisconnectingthedowncomerbracingfromthecontainmentandpedestalwal'1eliminatedtheinertialloadingfromthesesources.Table3.1indicatesthatbyremovingtheLOCAloadthestressmarginincreasesto71%.IfwefurtherremovetheSRV(ADS)stresses,andassumeanegligiblesubmergedstructureloadonthisdowncomerduetothelowsetpointMSRVcycling,thenthestressmarginincreasesto82%.

t TABLE3.1DOWNCOMERSTRESSESANDSTRESSMARGINFORWORST-CASEDOWNCOMERADJACENTTO,RHRSRVDISCHARGEDowncomerBendingStress=21ksiAllowableStress=45ksiStressMargin=1-21/45=53%SeismicContributionSRV(BuildingInertia)SRV(SubmergedStructure)LOCA(BuildingInertia)LOCA(SubmergedStructure)LOCA(TipLoad)38%0%(Negligible)24%3%9%26%100%

IIl TABLE3.2DOWNCOMERBRACINGSTRESSESANDSTRESSMARGINFORWORST-'CASEBRACINGADJACENTTORHRSRVDISCHARGEBracingMemberCombinedStress=1.6ksiAllowableStress=20ksiStressMargin=1-1.6/45=92%SeismicContributionSRV(BuildingInertia)SRV(SubmergedStructure)LOCA(BuildingInertia)LOCA(SubmergedStructure)LOCA(TipLoad)0%0%2%0%60%38%(Negligible)(Negligible)(Negligible)100%

~BracinkTable3.2alsoprovidesthestressmarginand%contributiontothetotalstressforeachloadforthemosthighlystressedbracingmemberadjacenttotheRHRSRVdischarge.This.tableindicatesthestressmargintobe92%,withallloadsexceptLOCAresultinginnegligiblestresses."Eliminatingallloads,exceptseismic,asbefore,increasesthestressmarginto100%.LinerPlateTheworst-casesuctionloadoccursduringnon-LOCAconditions,sinceaLOCAresults'napressurizedwetwellairspace.ThisnetpositivepressureoccursstaticallyandexceedsthesumofalldynamicsuctionloadscausedbySRV(ADS)+LOCAchugging.Fornon-LOCAconditions,thelinerplatewasevaluatedforthehydrostatic+SRV(ALL).But,whenconsideringthesuctionloadsonthelinerplateduetoRHRSRVdischarge,theSRV(ALL)mechanisticallyneednotbecombined.Asdescribedabove,cyclingofthelowsetpressureSRVsresultsinamuchlowersuctionloadtobecombinedwiththeRHRSRVsuctionload.Basedontheabove,muchconservatismexistsinthesubmergedstructuresadjacenttotheRHRSRVdischarge.OurpreliminaryevaluationofthevariousRHRSRVdischargeloadswhenconsideringtheabovedesignmarginsisprovidedbelow.TheRHRSRVdischargephenomenacausesseveralconcernsasfollows:waterjetloadduringventclearingairbubbleloadsduringventclearingsteamcondensationloadspotentialhighamplitudesteamcondensationloadsoriginatingfromhighwatertemperatureinthevicinityoftheRHRSRVdischarge.WaterJetLoadTherearenosubmergedstructuresinthevicinitybeneaththeRHRSRVdischarge.Therefore,loadsresultingfromacolumnofwaterbeingejectedfromthedischargelinearenotaconcern.AirBubbleLoadsLoadsontheworst-caseadjacentsubmergedstructuresandlinerplate(seeTables3.1and3.2)duetotheRHRSRVairbubbleloadareconsideredtobeboundedbythoseproducedbytheMSRVloadusedfordesign.ThisisbasedoncomparingtheparametersoftheRHRSRVdischargetothoseoftheMSRVs:

ur't oTheRHRdischargelinevolumeissmallerthantheMSRVdischarge,therefore,theairbubbleanditsresultantenergywouldbesmaller.oTheRHRSRVopensmoreslowlythantheMSRV,decreasingtheairbubbleloading.oAspreviouslyexplained,themassfluxthroughtheRHRSRVdischargelinewillbemuchlessthanthetheoreticalmaximumsteamfluxbasedontheratedflowthroughtheRHRSRV.ThisresultsinalowerbubblepressurerelativetotheMSRVload.oTheRHRSRVdischargelinesubmergenceisapproximately6'thighnormalwaterlevel,ascomparedtoaT-quenchersubmergenceof20.5'orhighnormalwaterlevel.ThisresultsinareducedventclearingpressurerelativetotheMSRVload.Inaddition,aspreviouslydescribed,thesubmergedstructuresandlinerplatecontainsufficientdesignmargintoaccommodateanyincreaseinthestressesduetoRHRSRVdischarge.Specifically,forthebracinganddowncomertheRHRSRVbubbleloadmustexceedthestressesduetoSRV(ADS)+LOCA+DESIGNMARGINtoresultinanoverstressedcondition.Similarly,fornon-accidentconditions,theRHRSRVsuctionloadmustexceedthehydrostaticpressure,andthelinerplateallowablestress,ifweassumethe'suctionloadduetocyclingof.,thelowsetpressureMSRVtobenegligible.SteamCondensationLoadsIThesteamflowthroughtheRHRSRVresultsinsteam'ondensationloadsatthedischargepipe.Again,thesteammassfluxthroughtheRHRSRVforeitherfailuremodewillbemuchlessthanthesteady-statesteammassfluxbasedontheratedflowoftheRHRSRV.Ourpreliminaryanalysisindicatedthattheexpectedsteammassfluxandassociatedsteamcondensationloadsresultedinstresseswithinthecodeallowables.Aswiththeairclearingload,significantdesignmarginexistsinthesubmergedstructuresandlinerplate,whichwebelieveexceedstheRHRSRVsteamcondensationloadwhencombinedwiththeappropriateloads.HihPoolTemeratureEffectsExperimentaldatahasshownthatsteamdischargeintowaterthatisataveryhighlocaltemperaturecanproducecomparativelylargeloads.BasedonourpreliminaryestimatesofRHRSRVsteamflux,anRHRSRVdischargeeventwillnotenterintosucharegime,sinceitisconsideredthatthesteamflowwillbeterminatedpriortosignificantlocalheatupintheareaofthedischarge.Aspreviouslydescribed,theoperatorhasseveralindicationsfromwhichtodeterminewhetheranuncontrolleddischargeofsteamthroughtheRHRSRVexists.Weassumehedetectsandisolatesthe 1[<

r(SCMat10minutesafter,thefailurethatoccurswhichleadstotheRHRSRV:discharge.Basedontheabove,webelievethewaterget,airclearing,andsteamcondensationloadsonthesubmergedstructuresandlinerplateduetoRHRSRVdischarge,whencombinedwiththeappropriateloads,arewithintheSSESdesignbasis.III.FutureActionReuired1.CalculatetheloadsonthesubmergedstructuresandlinerplateduetotheRHRSRVairclearingphenomenawhencombinedwiththeappropriateloads.Comparethesestressestothecodeallowables.2.ConfirmourpreliminaryanalysisthattheRHRSRVsteamcondensationloadsresultin'acceptablestressesonthelinerplateandadjacentsubmergedstructures.3.PerformpoolheatupcalculationduetoRHRSRVdischargetoverifythatthelocaltemperatureneartheRHRSRVdischargeremainsbelowthetransitiontemperatureforunstablesteamcondensationphenomena.4.DocumentabovetotheNRCbyMarch31,1983.-10-I.Issue3.2TheSTRIDEdesignprovidedonlynineinchesofsubmergenceabovetheRHRreliefvalvedischargelinesatlowsuppressionpoollevels.II.Assessment/ResonseInterpreting,this'asaconcernofdirect'teamdischargetowetwellenvironment,'orSSEStheRHRlineissubmerged,3.5'elowtheLNWL,hencethisisofnoconcerntoSSES.III.FutureActionReuired<lgNone I.Issue3.3DischargefromtheRHRreliefvalvesmayproduceairbubbledischargeorothersubmergedstructureloadsonequipmentinthesuppressionpool.II.Assessment/ResonseSeeresponseto3.1.III.FutureActionReuiredSeeresponseto3.1.-12-IS' I.Issue3.4TheRHRheatexchangerreliefvalvedischargelinesareprovidedwithvacuumbreakerstopreventnegativepressureinthelineswhendischargingsteamiscondensedinthepool.Ifthevalvesexperiencerepeatedactuation,thevacuumbreakersizingmaynotbeadequatetopreventdrawingslugsofwaterbackthroughthedischargepiping.Theseslugsofwatermayapplyimpactloadstothereliefvalveorbedischargedbackintothepoolatthenextreliefvalveactuationandapplyimpactloadstosubmergedstructures.II.Assessment/ResonseSSEShasperformedarefloodanalysistocalculatethemaximumheightofreflood(i.e.,waterslug)andconsequentialimpactloadsontheRHRSRVdischargepipingfollowingsubsequentactuationsoftheRHRsteamreliefvalve.Hydrodynamicloadsonsuppressionpoolsubmergedstructuresaredescribedintheresponseto3.1.Thisanalysisshowsthatthereflooddoesnotreachthevacuumbreaker(VRV)ortheRHRSRV.Therefore,animpactloadontheVRVorSRVduetoawaterslugdoesnotoccur,andtheVRVsizingisshowntobeadequate.II.FutureActionReuiredNone-13-IIVJgg 3.5TheRHRreliefvalvesmustbecapableofcorrectlyfunctioningfollowinganupperpooldumpwhichmayincreasethesuppressionpoollevelasmuchas5ftcreatinghigherbackpressureonthereliefvalves.II.Assessment/ResonseTheNRCdispositionedthisconcernasN/AforSSES.III.FutureActionReuiredNone-14-1JUi1ecII I.Issue3.6IftheRHRheatexchangerreliefvalvesdischargesteamtotheupperlevelsofthesuppressionpoolfollowingadesign'asisaccident,theywillsignificantlyaggravatesuppressionpooltemperaturestratification.II.Assessment/ResonseSteamcondensingisnotasafetymodeofRHRandisnotusedpost-accident.Itmaybeused"duringnormalreactorshutdownmodeforhotstandbyorvesseldepressurizationoperations.'hemodeoperatesbydrawingsteamfromtheHPCIsteamsupplyline;condensingintheRHRheatexchanger,andreturningthecondensatetothevesselviatheRCICpump.Thereliefvalvesdischarge3.5'elowthepoolsurface(ratherthan9"asintheMarkIII,design).IftheRHRsystemwasinth'ismodewhenaLOCA(whileshutdown)occurred,theredundant,inseries,safety-gradesteamsupplyvalveswillautomaticallyclose(seeresponseto3.1).Inothersafety-relatedmodes'ofoperation,theRHRsystempressureis,atalltimes,lowerthanthereliefvalvesetpoint.However,asingleactivefailure(open)ofthereliefvalvecouldbepostulatedwhiletheRHRSystemisoperatingpost-LOCA.IfthesystemwasintheLPCI,suppressionpoolcooling,orcontainmentspraymodes,thewatersourceisthesuppressionpool;therefore,notemperaturestratificationcouldoccur.Theshutdowncoolingmode(whichcouldbeinoperationafteranSBA)isinterlockedfromoperationuntilvesselpressureisbelow98psig.Inthiscasethereactorhasalreadybeendepressurizedandthepoolhas,therefore,alreadyperformeditspressuresuppressionsafetyfunctionsothatanypresumedtemperaturestratificationeffectswouldbeofnoconsequence.Finally,theresponseto4.4indicatedthatthermalstratificationposesnoproblemsforequipmentlocatedinthewetwellairspace,sincetheywerequalifiedtodrywellconditions.III.FutureActionReuiredNone15-C1"7I" I.IssueI3.7TheconcernsrelatedtotheRHRheatexchangerreliefvalvedischargelinesshouldalsobeaddressedforallotherECCSrelieflinesthatexhaustintopool(p.132of5/27/82transcript).II.Assessment/ResonseTherearenootherECCSrelieflinesthatdischargetothesuppressionpoolotherthansmallthermalreliefs.III.FutureActionReuiredNone-16-ll4yr 4.SuressionPoolTemeratureStratification4.1ThepresentcontainmentresponseanalysesfordrywellbreakaccidentsassumethattheECCSsystemstransferasignificantquantityofwaterfromthesuppressionpooltothelowerregionsofthedrywellthroughthebreak.Thisresultsinapoolinthedrywellwhichisessentiallyisolatedfromthesuppressionpoolatatemperatureofapproximately135'F.Thecontainmentresponseanalysis"assumesthatthedrywellpoolisthoroughlymixedwiththesuppressionpool.Iftheinventoryinthedrywellisassumedtobeisolatedandtheremainderoftheheatisdischargedtothesuppressionpool,anincreaseinbulkpooltemperatureof10'Fmayoccur.Footnote1:thedrywell.ThisconcernisrelatedtothetrappingofwaterinII.Assessment/ResonseForSSES,theamountofwater"trapped"inthedrywellislimitedtothe18"ventrisersinthedrywell.ThisrepresentsamuchsmallerproportionofthesuppressionpoolwatermassthanforaMarkIIIcontainmentdesign.ThisconcernpotentiallyaffectsthetwocontainmentanalysesusedforlicensingSSES:oThecontainmentanalysisdocumentedinSection6.2oftheFSAR.toTheMass6EnergyanalysisdocumentedinAppendixIoftheSSESDesignAssessmentReport(DAR).OurreviewofthecontainmentanalysisdocumentedinSection6.2oftheFSARindicatedthattrappingofthesuppressionpoolwaterinthedrywellwasnotconsidered.However,webelievetheconservatismsinthecontainmentanalysisexceedthepotentialnon-conservatismduetotheaboveconcern,-basedonthefollowing:oTheanalysisneglectedboththesteamcondensationonthedrywellstructures,aswellastheheattransferfromsuppressionpooltothecontainmentwalls.oTheanalysisassumedaservicewatertemperatureof95'Ffortheentiretransient.TheTechnicalSpecificationslimittheinitialservicewatertemperaturesto88'F.In'addition,asexplainedintheresponseto4.6,ourservicewaterspraypondanalysisindicatesthattheworst-caseservicewatertemperatureneverexceeds92.25'FwithoneunitinLOCAconditionandtheotherunitinforcedshutdown.-17-d1(IIPHll oFinally,thedecayheatcurveassumedintheanalysiswasveryconservative.Themorerecentcurvesprovideforalowerintegrateddecayheatfortheanalysis.TheMass&EnergyanalysisdocumentedinAppendixIoftheSSESDARwascompletedtoverifythatthescenarios(i.e.,stuckopenreliefvalve,isolation/scram,andsmallbreakaccident)whichleadtoabnormallyhighsuppressionpooltemperature,coincidentwithmainsteamSRVactuationandsteamflowthroughtheT-quencher,wouldnotresultinasuppressionpooltemperatureresponsewhichexceedsthemaximumpooltemperatureof207'FstipulatedbytheNRCforsafeT-quencheroperation.Ofthesescenarios,onlytheSBAcasesresultinabreachofthereactorpressurevessel,withthepotentialfortrappingsuppressionpoolwateronthedrywellfloor.TheSBAcasedidnotconsidertheeffectsofareductioninthesuppressionpoolwaterduetodrywelltrapping.Ourassessmentofthisconcernisprovidedbelow.TableI-2oftheDARindicatedamaximumcalculatedsuppressionpooltemperatureof193'FfortheSBACase3.a.Thus,thereexistsamarginof207-193=14'Fforthiscase.AswiththeSection6.2analysis,theoriginalMass8Energyanalysiscontainednumerousconservatismsasdescribedbelow:oTheanalysisneglectedthewatermasswithinthepedestal.Thiswaterisapproximately.5.7%ofthewater'massusedintheanalysis.oTheanalysistooknocreditforenergyabsorbedbythecontainmentstructure.oAgain,theanalysisassumedaservicewatertemperatureof95'F.Forbothscenarios,thecalculatedpooltemperatureconsideringthewatertrappedinthedrywellwouldnot'increasebythesamepercentdecreaseinpoolwaterlosttothedrywell(i.e.,1%decreaseinpoolmassequals1%increaseinpooltemperature).Thatis,thewatertrappedinthedrywellwouldabsorbsomeenergyfromthereactorsystem.Basedontheabove,webelievethisissueposesnoconcernsforSSES.III.FutureActionReuiredNone-18-lajf,JI' I.Issue4.2TheexistenceofthedrywellpoolispredicateduponcontinuousoperationoftheECCS.ThecurrentemergencyprocedureguidelinesrequiretheoperationstothrottleECCSoperationtomaintainvessellevelbelowlevel8.Consequently,thedrywellpoolmayneverbeformed.Footnote2:ThisissueappliesonlytothosefacilitiesforwhichEPGsareineffect.II.Assessment/ResonseTheSSEScontainmentresponseanalysisdoesnotdependontheformationofa"drywellpool."Asdescribed.intheresponseto4.1,thewatertrappedinthedrywellislimitedtothe18"'allventriser's.'f'th'drywellpoolisnotformed,as,postulatedherewith,thentheactualpooltemperatureresponsewouldbeconsistentwiththecontainmentanalysisdocumentedinSection6.2oftheFSAR,andtheMass5EnergyanalysisdocumentedinAppendixIofthe.DAR.1III.FutureActionReuiredNone-19-I.Issue4.3AllMarkIIIanalysespresentlyassumeaperfectlymixeduniformsuppressionpool.TheseanalysesassumethatthetemperatureofthesuctiontotheRHRheatexchangersisthesameasthebulkpooltemperature.Inactuality,thetemperatureinthelowerpartofthepoolwherethesuctionislocatedwillbeasmuchas7-1/2'Fcoolerthanthebulkpooltemperature.,Thus,theheat-transferthroughtheRHRheatexchangerwillbelessthanexpected.II.Assessment/ResonseAsshowninFSARFigure5.4-4b,theRHRpumpsuctionpenetratestheSSEScontainmentatEl.10'bovethebasemat,andthenT'sverticallywithsuctiontakenateachendoftheTapproximately8'nd12'bovethebasemat.Thiselevationcorrespondstothemid-planeofthepooland,therefore,weexpecttheRHRpump,suctiontemperaturetobe'atleastthebulkpooltemperature'.Asaresult,thisconcerndoesnotapplytotheSSESdesign.III.FutureActionReuiredNone-20-

)4'NlI I.Issue4.4Thelong-termanalysisofcontainmentpressure/temperatureresponseassumesthatthewetwellairspaceisinthermalequilibriumwiththesuppressi'onpoolwateratalltimes.Thecalculatedbulkpooltemperatureisusedtodeterminetheairspacetemperature.Ifpoolthermalstratificationwereconsidered,thesurfacetemperature,whichisindirectcontactwiththeairspace,wouldbehigher.Therefore,theairspacetemperature(andpressure)wouldbehigher.II.Assessment/ResonseIncontrasttoaMarkIIIcontainmentdesign,theSSESpeakpressureresponsetoaDBAoccursatapproximately15secaftertheaccidentbegins(seeFSARFigure6.2-2andTable6.2-5).Therefore,potentialpoolthermalstratificationwillhavenoeffectontheshorttermcontainmentpressureresponse.Thisconcernalsomayincreasethewetwellairspacetemperatureresponse.ForSSES,thisposesnoconcerns,sinceallequipmentlocatedintheairspacehasbeenqualifiedtothedrywelltemperatureprofile(maximumtemperatureequalto340'F)whichenvelopesanypotentialincreasesinthesurfacepooltemperature.III.FutureActionReuiredNone-21-Issue4.5Anumberoffactorsmayaggravatesuppressionpoolthermal'stratification.Thechuggingproducedthroughthefirstrowofhorizontalventswillnotproduceanymixingfromthesuppressionpoollayersbelowthe.ventrow.Anupperpooldumpmaycontributetoadditionalsuppressionpooltemperaturestratification.ThelargevolumeofwaterfromtheupperpoolfurthersubmergesRHRheatexchangereffluentdischargewhichwilldecreasemixingofthehotter,upperregionsofthepool.Finally,operationofthecontainmentsprayeliminatestheheatexchangereffluentdischargejetwhichcontributestomixing.Footnote3:ForMarkIandIIfacilities,'onfineyourresponseonthisissuetothoseconcernswhichcanleadtopoolstratification(e.g.,operationofthecontainmentspray).II.Assessment/ResonseInSSES,thecontainmentsprayfallstothediaphragmfloor,flowsthroughthedowncomersandexitsatthemid-planeofthepool,approximately12'bovethebasemat.Thus,webelievecontainmentspraywillnotaggravateanypoolstratification.Inaddition,as,describedintheresponseto4.4,anypoolthermalstratificationhasnoeffectontheSSEScontainmentdesign.III.FutureActionReuiredNonekP-22-PIP I.Issue4.6Theinitialsuppressionpooltemperatureisassumedtobe95'Fwhilethemaximumexpectedservicewatertemperatureis90'FforallGGNSaccidentanalysesasnotedinFSARTable6.2-50.Ifthe'ervicewatertemperatureisconsistentlyhigherthanexpected,asoccurredatKuosheng,theRHRsystemmayberequiredtooperatenearlycontinuouslyinordertomaintainsuppressionpooltemperatureatorbelowthemaximumpermissiblevalue.II.Assessment/ResonseAsstated,thisissueappearstobeanoperationalconcernandisnotrelatedtothesafeoperationoftheplantsincecontinuous,frequentoperationoftheRHRandservicewatersystemsdoesnotaffectthesafeoperationoftheplant.Theinitialsuppressionpooltemperatureisassumedtobeat90'FforSSESaccidentanalysis.RHRSWisusedtocoolthesuppressionpoolwhichtakessuctionfromthespraypond.Thespraypondhasanareaof'8acresandadepthof10-1/2ftwithamaximum'designtemperatureof88'F(FSARTables9.2-2789.2-23).Thistemperatureisbasedonaveryconservativeanalysisofsitemeteorologyandassumesthatallthewaterinthespraypondwillreachtheworstambienttemperaturewithoutconsideringtheeffectsoftemperature,'stratificationinthepond.Ourspraypondanalysisshowsthateve'nforthelong-termpost-accidentconditionwithoneunitintheLOCAconditionandtheotherunitatforcedshutdown,themaximumpondtemperatureisonly92.25'F(FSARTable9.2-12)fortheminimumHeatTransfercase.Wedonotexpectthebulktemperatureofspraypondtoexceed88'F.TheTechnicalSpecificationsrequirethattheplantbeinshutdownconditioniftheaveragepondtemperaturesexceed88'F.Inaddition,theTechnicalSpecificationsrequireasuppressionpooltemperaturebelow90'F(exceptduringtestingwhichaddsheattothepool).Ifthepooltemperatureexceeds90'F,theTechnicalSpecificationsdirecttheoperatortorestorethetemperaturetolessthanorequalto90'Fwithin24hoursorbeinatleasthotshutdownwithinthenext12hoursandincoldshutdownwithinthefollowing24hours.Thus,iftheSWandRHRsystemsfailtomaintainthepooltemperaturebelow90'Fduringhotweather,thentheplantwillbebroughttoanorderlyshutdown,andthisconcernbecomesanoperationalproblem.III.FutureActionReuiredNone-23-4t I.Issue4.7AllanalysiscompletedfortheMarkIIIaregenericinnatureanddonotconsiderplantspecificinteractionsoftheRHRsuppressionpoolsuctionanddischarge.II.Assessment/ResonseThesketchonthenextpageshowstherelativepositionsofRHRsuctionanddischarge.Thisconfigurationeliminatesanyconcernwiththedischargeeffluentshortcircuitingthepoolandassuresadequatepoolmixing.III.FutureActionReuiredNone-24-0 0's(4,vaA/204/2'2l2p3gCIplf.s$.o853+iAkliAtC(o)(to&Sdim>oopsXQ~SationgSeraiIofsac.'Ron,SCC.ACxt~Z.hsew~~a4o<f49>~><"~)a:l8'ahovcbaseman~

0RW00AII.RSu~'OnVneS8rOghgas.e-leak'IT~58-ZoSA..I.);-ZOZCServetlNc4scLcroIcQngt'groutpcoielv~<'cnh'an6 "&'NNLQLo4,'70~00ZoLUgCQ0wWg)o0zIWXIgL.MG~~l'1(~I~5C(lcl)0~%]qV/7ICAL0l0co0aolParr:Ii]..c.>J/g/0oQuc6cH/89',h'rrf.nvegX-zoZS)(-zaz3>Pg('etcnce5eI6B-I/n-l.IBR-iu-z,pisVi6$]gQOII-:RIgS~chon<.Uncsd-re+pacJ>4'iouspf-Zom.)gZosp+evvet4c.8sc.W~oie4'neC4rooglileonetv~I.'or>-yooq-g,Tlirtabove.geo+.e.l-v'i'a'igpI'ga(

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I.Issue4.8OperationoftheRHRSysteminthecontainmentspraymodewilldecreasetheheat'transfercoefficientthroughtheRHRheatexchangersduetodecreasedsystemflow.TheFSARanalysisassumesaconstantheattransferratefromthesuppressionpoolevenwithoperationofthecontainmentspray.II.Assessment/ResonseThisissueisinterpretedasbeingconcernedwiththepotentialforincreasedbulkpooltemperatureandcorrespondingwetwellairspacepressureandtemperature.Asdiscussedintheresponseto4.4,thepeakcontainmentpressureisgovernedbytheshort-termDBALOCAresponse,andnotbythelong-termresponse.Also,asdiscussedintheresponseto4.4,theonlyconcernrelatedtoincreasedsuppressionpool/wetwellairspacetemperatureshastodowithenvironmentalqualification.Sinceequipmentinthewetwellhasbeenqualifiedtodrywelltemperatureconditions,whichboundsthewetwellconditions,anypresumeddecreaseinheatremovalratefromthesuppressionpoolisnotofconcern.Nevertheless,itcanbedemonstratedthattheoperationofcontainmentsprayswouldhavenegligibleeffectonpeakbulksuppressionpooltemperature.AsopposedtothestandardMarkIIdesignwherecontainmentsprayandsuppressionpoolflowratesareidentical,SSEShasasmaller(9000gpm)containmentsprayratethansuppressionpoolcoolingflowrate(10,000gpm).However,asshowninFSARTable6.2-6,,theworst-casesuppressionpoolpeaktemperatureoccurswhennocontainmentsprayisassumed(Case"D"),i.e.,theRHRsystemisalwaysinthesuppressionpoolcoolingmode.AlthoughthevaluesinFSARTable6.2-6werecalculatedpriortothemodificationthatresultedinthedecreasedcontainmentsprayrate,itcanbeseenthatanominalchangeinsprayflowratehaslittleeffectonpeakpooltemperature.ComparingCase"B"toCase"C"(allspraycases)wheresprayflowrateisdecreasedby5000gpm,itisseenthatthepooltemperatureincreasesbyonly3.1'F.Adecreasefrom10,000gpmto9000gpm,then,wouldleadtoaninsignificantchangeinpooltemperature,andwouldclearlybe'oundedbythe'eak(nospray,Case"D").temperatureof208.2'F.III.FutureActionReuiredNone-25-ltI11fI'h I.Issue4.9Theeffectonthelong-termcontainmentresponseandtheoperabilityofthespraysystemduetocyclingthecontainmentspraysonandofftomaximizepoolcoolingneedstobeaddressed.Alsoprovideandjustifythecriteriausedbytheoperatorforswitchingfromthecontainmentspraymodetopoolcoolingmode,andbackagain(pp.147-148of5/27/82transcript).II.Assessment/ResonsetOurassessmentoftheaboveconcernisprovidedbelow:1.ContainmentPressureResponse"Asdiscussedin4.4,thepeakpressureresponsetoaDBAoccursduringtheshort-termblowdown.Forthelong-termpressureresponse,theresponseto4.8indicatedthatSSES'analyzedforboththeallsprayandnospraycases.Bothcaseswereacceptable.Thesecasesenvelopthecontainmentresponseduetocyclingthecontainmentspraysonandoffaspostulatedabove.2.SuppressionPoolTemperatureResponseForSSES,thecyclingofthecontainmentspraystomaximizepoolcoolingisnotrequired.Again,asdiscussedunder4.8,boththeallsprayandnospraycaseswereevaluated.FSARFigure6.2-8indicatesthateithercaseresultsinanacceptablepooltemperatureresponse.Thus,thesetwocasesenvelopethepooltemperatureresponsetoanypotentialcyclingfrompoolcoolingtothesprays.Inaddition,emergencyprocedure'E0-00-023,"ContainmentControl,"providesthecriteriaforoperationofthespraymodeorpoolcoolingmodeoftheRHRsystem.Theprocedurewaspreparedfrom.theemergencyprocedureguidelines.developedbytheBWROwnersandGE.Thisprocedurerequiresinitiationofpoolcoolingwhenthesuppressionpooltemperatureexceeds90'F,andisthepreferredmodeforcontainmentheatremoval.However,theprocedurerequiresinitiationofthedrywellandsuppressionpoolsprays,ifthecontainmenttemperatureandpressureexceedpredeterminedvalues.ForSSES,beforethedrywelltemperaturereaches340'F,but'fterdrywelltemperaturereaches320'F,theproceduredirectstheoperatortoinitiatethedrywellsprays.Theproceduredirectstheoperatortoinitiatewetwell,spraywithin30minutesofreaching30psigdrywellpressure.ThisactionisrequiredtobeconsistentwiththeSSES-uniquesteambypassanalysis.-26-g4tPd1,I Inaddition,theproceduredirectstheoperatortoinitiatesuppressionpoolspray,ifthesuppressionpoolchamberpressureapproachestheSuppressionPoolSprayLimit(seefigurenextpage).Furthermore,theproceduredirectstheoperatortoinitiatedrywell'sprays,ifthesuppressionchamberpressureapproachesthePressureSuppressionLimit(seefigurenextpage).TheSuppressionPoolSprayLimitinsuressuppressionpoolspraybeforereaching50%ofthesuppressionchamberdesignpressure.ThePressureSuppressionLimitinsuresdrywellsprayinitiationbeforesuppressionchamberpressureindicatesthatpressuresuppressionhasbecomeineffective.Toaccommodateanyrequiredcyclingofthecontainmentsprays,theRHRsystemandpipinghavebeendesignedforapproximately7,000thermalcycles.III.FutureActionReuiredNone-27-s.s'sIr~Is~~s~srQr;~rQ.)~rCS~~Le,cl.r~r}~~~gr'ss~,~s5"~2Page1of1AttachmentCEO-00-023Revision1Page9of18SUPPRESSIONPOOLSPRAYLIMITr~&s}'.II}ss}'}~'i-}.I~~~II.I}/rsrrsrs~rIss/ss},~~i'rs~.~rLu~~'rs~Xa)JIs~~sss'Is1~.I/'SrI~~r~s~~s~~)isssIs~I!iiis~Is~s~;r1sI.';I's)Ir.'s~Ir'.~.~!ss!r"I})iI~s~IsI)s~s},'Ss~~I/')'"~~s'.is})I'II}I}s:}r,",)II~,sssS~I!'i')}}ss},Isr~~r~IIIs~s~s~i:Is~.III!lrrIs'~"i//rl)ir..~//C')rIssi)i.iI'!1;II.',~)I!ss~rr,'rsIsSrsss.sr~~i:ss',:iI~/I'-.I';..':.:.IIi::s.I//'IsssssIs~sr~irs,srr8~i'!II~s'I~~srippreaag,o~}O@zest'I~~sssr'~ssss}~2naLLevej(t}r1 J AttachmentD.EO-00-023Revision1Pagellof18PRESSURESUPPRESSIONLIMITgs~'I~~IS'sr.~sr')<<4-'.isvsoee'li~~~~If,sII!isIIIrs~~~(,i/~rv~osSI4vv\e+e~~~rII'8~-~~~V~eq,pv<<os~'s~',~e+ovosS~~/~rIi'I,JI~J~SW~sril~I.>>Y."~'--'~I~,~'I(~I~!I~I+siIIslIi~\I,s()sDosi!~~IlI.I'!iJlI/I!i~!iI(J';!~!!:IIIIt~I!~Jr+I~~C(oI!sss)I~~~II~7IsiIl'!iIII(I'iIIIl'!!tI'I!!':II',.iII'(Ii!!'~:!i;!sQCOIIII'!i!!.'E.IIiIi'.!riil.l.Lvii!I!iII~~!it!~sIII'II~!liI~l~~I,~~~IiI~I'I'l~lIsI.'!I,iit~!~IIIIs~I~Il~"~I~:.0-,F'."20':2eeeeeeePssppzeee)sse,Lied.".i!.!'.III~~i!t!~I,~!".0'"'45-.'50..5;rI~zfea~coatafxmenkWate~ve3D~/s e I.Issue4.10Justifythatthecurrentarrangementofthedischargeandsuctionpointsofthepoolcoolingsystemmaximizespoolmixing."II.Assessment/ResonseThefiguresattachedtotheresponseto4.7showtherelativepositionsoftheRHRsuctionanddischarge.ThesefiguresindicatetheRHRdesignwillprovideadequatepoolmixing.III.FutureActionReuiredNone-28-lQiJ I.Issue5.DrywelltoContainmentBypassLeakage5.1Theworst-caseofdrywelltocontainmentbypassleakagehasbeenestablishedasasmallbreakaccident.Anintermediatebreakaccidentwillactuallyproducethemostsignificantdrywelltocontainmentleakagepriortoinitiationofcontainmentsprays.,II.Assessment/ResonseAsrequiredbySection6.2.1.1.coftheStandardReviewPlan,PP&Lcompletedasteambypassca/culationforapostulatedsteam,bypassareaofA//Kequalto0.0535ftforSBAconditions.PLA-923datedSeptember3,1981,transmittedtoyoutheresultsofthesecalculations.TheSBAconditionsprovidedaconservativeanalysisbasedonthefollowing:oTheanalysismaximizedthedrywell-to-wetwellAP,whichdrives'hesteamintothewetwellairspace.Fromllsecafterthebreakoccurs,itassumedthatpuresteamatadrywell-to-wetwellAPequaltotheventsubmergencewasavailableforsteambypass.oTheanalysisalsomaximizedthetimeperiodoverwhichthesteambypassoccurred.Itassumedthatnovesseldepressurizationoccurred,andthatthedrywell-to-wetwellAPequaltothesubmergenceexistedfortheentiresteambypasscalculation.Theanalysisindicatedthatsufficienttimeexistsforthecontainmentpressuretogofrom30psigtothedesignpressureof53psigfortheoperatortomanuallyinitiatethecontainmentspray.Onceinitiated,thesprayheatremovalrateissufficienttoterminatethecontainmentpressureincrease.Furthermore,SupplementNo.3totheSSESSafetyEvaluationReportdocumentedyourreviewandacceptanceoftheaboveanalysis.III.FutureActionReuired'one-29-I.Issue5.2UnderTechnicalSpecificationlimits,bypassleakagecorrespondingtoA/MK=O.lftconstitutesacceptableoperatingconditions.Smaller-than-IBA-sizedbreakscanmaintainbreakflowintothedrywellforlong-timeperiods,however,becausetheRPVwouldbedepressurizedovera6-hourperiod.Given',forexample,anSBAwithA/~K=0.1,projectedtimeperiodforcontainmentpressuretoreach15psigis2hours.Inthelatter4hoursofthedepressurizationthecontainmentwouldpresumablyexperienceever-increasingoverpressurization.Footnote4:ForMarkIandIIfacilities,refertoAppendixItoSection6.2.1.1.coftheStandardReviewPlan(SRP).II.Assessment/ResonseAsdescribedintheresponseto5.1,PPSLperformedaSSESuniquesteambypasscalculationpertherequirementsofAppendixItoSection6.2.1.1.coftheSRP.Thesecalculationsassumednovesseldepressurizationandadrywell-to-wetwellAPequaltothesubmergenceforthedurationofthetransient.Thisanalysis,asanysteambypasscalculationwould,showedthatthe"containmentwouldpresumablyexperienceever-increasingoverpressurization,"ifnocontainmentsprayinitiationoccurred.However,whentheoperatorinitiatesthecontainmentsprays,thepressureincreaseterminates.The.subjectanalysisshowedthatsufficienttimeexistsfor'theoperator.toinitiatethecontainmentsprays,whilethecontainment'pressureincreasesfrom30psigtothedesignpres'sure'of53'psig.NfIIII.FutureActionReuir'ed'one-30-I.Issue5.3Leakagefromthedrywelltocontainmentwillincreasethetemperatureandpressureinthecontainment.Theoperatorswillhavetousethecontainmentsprayinordertomaintaincontainmenttemperatureandpressurecontrol.GiventhedecreasedeffectivenessoftheRHRsysteminaccomplishingthisobjectiveinthecontainmentspraymode,thebypassleakagemayincreasethecyclicaldutyofthecontainmentsprays.II.Assessment/ResonseTheresponsesto4.8and4.9discussedtheeffectsonthelong-termcontainmentanalysisofcyclingtheRHRsystembetweenthesprayandpoolingmodes.Asnotedthere,theSSEScontainmentdesigncanaccommodateeitherallornosprayswithnoadverseeffectsonthelong-termcontainmenttransients.Thesecasesenvelopethecontainmentresponsewithcyclingofthecontainmentsprays.Furthermore,ifsteambypassrequirescyclingbetweenthespraysandpoolcooling,thesystemdesignwillnotsuffer,sincethespraysweredesignedforupto7000thermalcycles.III.FutureActionReuiredNone-31- 'lll I.Issue5.4Directleakagefromthedrywelltothecontainmentmaydissipatehydrogenoutsidetheregionwherethehydrogenrecombinerstakesuction.Theanticipatedleakageexceedsthecapacityofthedrywellpurgecompressors.Thiscouldleadtopocketingofhydrogenwhichexceedstheconcentrationlimitof4%byvolume.Footnote5:Thisconcernappliestothosefacilitiesatwhichhydrogenrecombinerscanbeused.II.Assessment/ResonseInSSES,twohydrogenrecombinersarelocatedinthedrywellandtwointhewetwellairspace.ForaninertedcontainmentsuchasSSES,thepertinentconcentrationlimitis5%oxygen.Whileoperatingthedrywellrecombiners,drywellmixingisprovidedbyoperatingthesafety-relateddrywellfans.Forthewetwellairspace,pocketingofhydrogenisnotexpected,sincetheairspaceisalarge,unpartitioned,openvolume.However,mixinginthewetwellcanbeaccomplishedbyoperationofthewetwellsprays.III.FutureActionReuiredNone32 I.Issue5.5Equipmentmaybeexposed,tolocalconditionswhichexceedtheenvironmentalqualificationenvelopeasaresultofdirectdrywelltocontainmentbypassleakage.II.Assessment/ResonseAsexplainedintheresponseto4.4,allequipmentlocatedinthewetwellairspacehasbeenqualifiedtodrywellconditions,whichenvelopeanyconcernsduetodrywell-to-wetwellbypassleakage.III.FutureActionReuiredNone-33-I'tlI/lg I.Issue5.6and5.7II.Assessment/ResonseDispositionedbytheNRCasnotapplicableforMarkII.III.FutureActionReuiredNone-34-I.Issue5.8Thepossibilityofhightemperaturesinthedrywellwithoutreachingthe2psighighpressurescramlevelbecauseofbypassleakagethroughthedrywellwallshouldbeaddressed(pp.168-174of5/27/78transcript).II.Assessment/ResonseThedrywelldesigntemperatureis"governedbyasmallreactorsteambreak.TheFSARSBAanalysis(seeSection6.2.1)demonstratesittakesabout6hourstoceasereactorblowdownfollowinganSBAwhichisaccomplishedbyanorderlyreactorshutdownwithacooldownratelimitedto100'Fperhour.Duringthisblowdownperiod,steamenteringthedrywellisinasuperheatedconditionduetoconstantenthalpydepressurizationofhighpressuresaturatedsteam.Thedrywelldesigntemperatureisdeterminedbyfindingthecombinationofprimarysystempressureanddrywellpressurethatproducesthemaximumsuperheatedsteamtemperature.Thistemperatureisthenassumedtoexistfortheentiresix-hourperiod.Theresultantmaximumsuperheatedsteamtemperatureis340'Fcorrespondingtotheprimarysystempressureofapproximately450psiaandanassumedmaximumdrywellpressureof35psig.This340'Fisthereforechosenasthedrywelldesigntemperature.Consideringapostulatedsmallbreakwithoutinitiatingautomatichighdrywellpressurescrambecauseofbypassleakage,itwouldnotbepossibletoexceedthecurrentdesigntemperatureforthefollowingreasons:1.TheSSESTechnicalSpecificationslimitofdrywellpressureis-1psigto+2psig.Thescramsetpointis1.72psig.Thepost-SBAshort-termtransientwithoutinitiatingscramat1.72psigdrywellpressureisonlypossibleforacaseof"smaller-than-small-break-size"inwhichsteamisweepingintothedrywellanddrivingnon-condensablesintowetwellthroughthepotentialleakagepaths.Duetothisbyp'assleakageeffectfollowingasmaller-than-small-break',anautomaticdrywellpressurescramcouldbedelayedforthetimeneededtoslowlypressurizethedrywelltothe1.72psigscramlevel.Thereactorsteam,.enteringthedrywellpriortotheinitiationofscram,.isin'thesuperheatedconditionwhichislessthan340'FpredictedinFSARanalysis.(Forexample,asnotedinFSARSection6.2.1,decompressionof1000psiasaturatedsteamintoatmospherewillresultin298'Fsuperheatedsteam.)Therefore,thedrywelltemperaturecouldnotexceedthecurrentdesigntemperature.2.Anysignificanttemperatureexcursionthatcouldresultfromsuchapostulatedeventwillbepreventedbyoperatoraction.TheoperatorisrequiredbytheTechnicalSpecificationstomaintainthedrywellairspacetemperaturebelow135'F.Ifthetemperaturerisesandexceeds135'F,emergencyoperatingprocedureE0-00-023,"ContainmentControl,"requirestheoperatortostartallavailabledrywell-35-Tipltf coolers.Ifthedrywellcoolersareunabletoreducethetemperature,theemergencyoperatingproceduresrequireinitiatingthecontainmentspraysforacontainmenttemperaturebetween320and340'F.3.Finally,therewillbenosignificantdelayofscram,sincerelativelysmallbypassleakagecapacityexistsinaMarkIIdesign.Thus,thecontainmentpressurewillreach1.72psiginashorttimeperiod.III.FutureActionReuiredNone~-36-I.Issue6.1WeunderstandthatGEhasrecommendedforMarkIIIcontainmentsthatthecombustiblegascontrolsystemsbeactivatedifthereactorvesselwaterleveldropstowithinonefootofthetopoftheactivefuel.Indicatewhatyourfacilityisdoinginregardtothisrecommendation.II.Assessment/ResonseThisisnotapplicabletoSSES.Nosuchactionisrequired,sincetheSSEScontainmentisinertedandshort-termHcontrolisnotrequired.III.FutureActionReuiredNoneYt-37-

I.Issue6.2GeneralElectrichasrecommendedthataninterlockbeprovidedtorequirecontainmentspraypriortostartingtherecombinersbecauseofthelargequantitiesofheatinputtothecontainment.Incorrectimplementationofthisinterlockcouldresultinaninabilitytooperatetherecombinerswithoutcontainmentspray.Footnote5:Thisconcernappliestothosefacilitiesatwhichrecombinerscanbeused.II.Assessment/ResonseThereisnointerlockbetweenthecontainmentspraysandtherecombiners.III.FutureActionReuiredNone-38-C-Nl I.Issue6.3Therecombinersmayproduce"hotspots"neartherecombinerexhaustswhichmightexceedtheenvironmentalqualificationenvelopeorthecontainmentdesigntemperature.Footnote5:Thisconcernappliestothosefacilitiesatwhichrecombinerscanbeused.II.Assessment/ResonseTheSSESdesignhasaccountedforrecombiner"hotspots."Therecombinersareofanaturalcirculationtypedesignwithhotairexhaustedfromthetop,sothat"hotspots"arelimitedtothelocalareadirectlyabovetherecombiners.Inthedrywellnoequipmentexceptacabletrayisneartherecombinerexhaust.Thecabletrayhasbeenprovidedwithdeflectorswhicharedesignedtoinsulatethecabletrayandpreventitstemperaturefromexceedingdesignlimits.Temperaturemeasurementsatthecabletraywhileoperatingtherecombinershaveverifiedthatthedesignandinstallationofthedeflectorsareadequate.Thewetwellrecombinersarelocatedatahighelevationdirectlybelowthediaphragmslab,andallequipment(suchasSPOTMOSRTDs)arelocatedbelowtherecombiners.Therefore,therearenoenvironmentalqualificationconcerns.III.FutureActionReuiredNone-39-

I.Issue6.4ForthecontainmentairmonitoringsystemfurnishedbyGeneralElectric,theanalyzersarenotcapableofmeasuringhydrogenconcentrationatvolumetricsteamcondensationabove60%.Effectivemeasurementisprecludedbycondensationofsteamintheequipment.II.Assessment/ResonseThecontainmentairmonitoringpipingisprovidedwithheattracing"poweredfromsafetygradesourcessothatnocondensationofsteamwilloccur.NotethatSSESusesComsip-DelphimonitorsratherthanGEequipment.III.FutureActionReuiredNone-40-I.Issue6.5Discussthepossibilityoflocaltemperaturesduetorecombineroperationbeinghigherthanthetemperaturequalificationprofilesforequipmentintheregionaroundandabovetherecombiners.Statewhatinstruction's,ifany,areavailabletotheoperatortoactuatecontainmentspraystokeepthistemperaturebelowdesignvalues(pp.183-185of5/27/82transcript).1Footnote5:Thisconcernappliestothosefacilitiesatwhichrecombinerscanbeused.II.Assessment/ResonseEmergencyoperatingprocedureE0-00-023,"ContainmentControl,"requirestheoperatortoinitiatetheH2recombinersbeforeanH2concentrationof3%byvolume.Withaninertedcontainment,thisoccurswithinapproximately24hoursafterthebreakfortheworst-caseanalysis(seeFSARSubsection6.2.5.3).Theheatoutputfromtherecombinersisasmallfractionofthe,totalheatinputtothecontainmentfromthereactorvessel.Thus,recombineroperationwillnotaffecttheglobaltemperatureresponseofthecontainment.Inaddition,asdescribedintheresponseto6.3,theSSESdesignconsideredthelocaleffectsofrecombineroperation.fl,Intheeventthecontainmenttemperaturesubstantiallyincreases,emergencyoperatingprocedureE0-00-023,"ContainmentControl,"requirestheoperatortoactuatethedrywellspraysbeforethedrywelltemperaturereaches340'F,butafterthedrywelltemperaturereaches320'F.III.FutureActionReuiredNone-41-J'AC1kg~IUAII40 I.Issue7.ContainmentPressureResonse7.1Thewetwellisassumedtobeinthermalequilibriumwithaperfectlymixed,uniformtemperaturesuppressionpool.Asnotedundertopic4,thesurfacetemperatureofthepoolwillbehigherthanthebulkpooltemperature.Thismayproducehigherthanexpectedcontainmenttemperaturesandpressures.II.Assessment/ResonseReferto4.4.III.FutureActionReuiredNone-42-I.Issue7.2ThecomputercodeusedbyGeneralElectrictocalculateenvironmentalqualificationparametersconsidersheattransferfromthesuppressionpoolsurfacetothecontainmentatmosphere.ThisisnotinaccordancewiththeexistinglicensingbasisforMarkIIIenvironmentalqualification.Additionally,thebulksuppressionpooltemperaturewasusedintheanalysisinsteadofthesuppressionpoolsurfacetemperature.Footnote6:ThisissueasphrasedappliesonlytoaMarkIIIfacility.However,theconcerncanbegeneralizedandappliedtotheearliercontainmenttypes.ForMarkIandIIfacilities,indicatewhatmethodologywasusedtocalculatetheenvironmentalqualificationparametersincludingadiscussionofheattransferbetweentheatmosphereinthewetwellandthesuppressionpool.II.Assessment/ResonseAsexplainedin4.4,allequipmentlocatedinthewetwellairspacewasqualifiedtothedrywelltemperatureprofile(T=340'F).Thisenvelopesanyconcernsrelatedtopoolthermalsrratification.maxIII.FutureActionReuiredNone-43-Issue7.3Theanalysisassumesthatthewetwellairspaceisinthermalequilibriumwiththesuppressionpool.Intheshorttermthisisnon-conservativeforMarkIIIduetoadiabaticcompressioneffectsandfinitetimerequiredforheatandmasstobetransferredbetweenthepoolandcontainmentvolumes.Footnote6:ThisissueasphrasedappliesonlytoaMarkIIIfacility.However,theconcerncanbegeneralizedandappliedtotheearliercontainmenttypes.ForMarkIandIIfacilities,indicatewhatmethodologywasusedtocalculatetheenvironmentalqualificationparametersincludingadiscussionofheattransferbetweentheatmosphereinthewetwellandthesuppressionpool.II.Assessment/ResonseDuringpoolswellfollowingtheDBALOCA,thewetwellairspaceisassumedtocompressadiabatically(NEDE-21544-P,GE,December,1976).Thus,thewetwellairspaceandtemperaturearerelatedvia1-y=constantForaninitial'wetwellairspacepressureandtemperatureof14.8psiaand130'F,thetemperatureatthetimeofmaximumwetwellcompressionof56.1psia(SSESDARFigure4-39)canbedeterminedtobe342'F.Thecompressionanddecompressionoftheairspacetakesplaceinapproximately2sec.Duringthistimeperiodnoappreciableheattransfercanoccur,sincethefinalpressure(afterpoolfallback)is,muchlessthan56.1,whichreducesthepeaktemperaturetolessthan342'F.Thus,,thiseventisnotincludedintheenvironmentalqualificationdesign.However,asdescribedintheresponseto4.4,allequipmentwasqualifiedtothedrywellprofilewithapeaktemperatureof340'F.II.FutureActionReuiredNone-44-lpJ1E)II'L I.Issue8.ContainmentAirMassEffects8.1ThisissueisbasedonconsiderationthatsomeTechnicalSpecificationsallowoperationatparametervaluesthatdifferfromthevalues'sedinassumptionsforFSARtransientanalyses.Normallyanalysesaredoneassuminganominalcontainmentpressureequaltoambient(0psig),atemperaturenearmaximumoperation(90'F)anddonotlimitthedrywellpressureequaltothecontainmentpressure.TheTechnicalSpecificationsoperationunderconditionssuchasapositivecontainmentpressure(1.5psig),temperatureslessthanmaximum(60or70'F)anddrywellpressurecanbenegativewithrespecttothecontainment(-0.5psid).AllofthesedifferenceswouldresultintransientresponsedifferentthantheFSARdescriptions.II.Assessment/ResonseiForSSES,theTechnicalSpecificationslimitthecontainmentpressuretobetween-1.0and2.0psig.TheFSARanalysisassumed.aninitialwetwellanddrywellpressurebetween0.1and1.5psig(seeTable6.2-4).TheTechnicalSpecificationsalsolimitthenormaloperatingsuppressionpooltemperaturetoamaximumof90'F.TheFSARanalysisassumedaninitialpooltemperatureof90'F(seeFSARFigure6.2-3).Inaddition,theTechnicalSpecificationslimittheaveragedrywelltemperaturetoamaximumof135'F,whiletheFSARassumedadrywelltemperaturebetween135'Fand150'F.Theanalysisalsoassumedaninitialwetwellairspacetemperaturebetween90'Fand150'F.Theshort-termpressureresponsetoaDBALOCAdocumentedinFSARSection6.2calculatedamaximumdrywellpressureof44.2psig,comparedtoadesignpressureof53psig.Inaddition,thecontainmentresponseignoredtheheatabsorbedbythecontainmentstructures.Inconclusion,theTechnicalSpecificationslimittheparametervaluesduringoperationtothoseassumedintheFSARtransientanalysis.tIII.FutureActionReuiredNone-45-lla~lpf4'Pullt I.Issuea8.2ThedraftGGNStechnicalspecificationspermitoperationoftheplantwithcontainmentpressurerangingbetween0and-2psig.Initiationofcontainmentsprayatapressureof-2psigmayreducethecontainmentpressurebyanadditional2psigwhichwouldleadtobucklingandfailuresinthecontainmentlinerplate.II.Assessment/ResonseFortheMarkIIIdesign,containmentsprayinitiationoccursautomaticallyonhighdrywellpressure.Withautomaticinitiation,aspurioussignalcouldresultinaninadvertentsprayactuation.However,forSSES,thecontainmentspraysmustbeinitiatedbymanualaction.Inordertoinitiatethesprays,boththeinboardandoutboardisolationvalvesmustbeopened.TheoperatingproceduresrequirepermissionfromtheShiftSupervisortoopenthevalves,andthe~kelockswitchplacedtoMANOVERRIDE.Basedontheabove,webelieveinadvertentsprayactuationduringnormaloperationrequiresextraordinarycircumstancesbeyondthedesignbasisoftheplant.Nevertheless,weevaluatedtheworst-casedepressurizationanalysisfornon-accidentconditionsforSSESbasedontheminimumTechnicalSpecificationinitialpressureof13e7psia,andthemaximumTechnicalSpecificationdrywelltemperatureof135'F.Thesevaluesminimizedthepartialpressureofthenon-condensablesandmaximizedthevaporpressure.Ouranalysisrevealedthataninadvertentsprayactuationwiththeseinitialconditionsresultedinacontainmentnegativepressurewhichdoesnotexceedthecontainmentnegativedesignpressureof-5.0psig(referenceFSARTable6.2-1).III.FutureActionReuiredNone-46-' 1'H I.Issue8.3Ifthecontainmentismaintainedat-2psig,thetoprowofventscouldadmitblowdowntothesuppressionpoolduringanSBAwithoutaLOCAsignalbeingdeveloped.II.Assessment/ResonseTheNRCdispositionedthisconcernasN/AtoSSES.III.FutureActionReuired1None-47-I.Issue8.4Describeallofthepossiblemethods,bothbeforeandafteranaccident,ofcreatingaconditionoflowairmassinsidethecontainment.Discusstheeffectsonthecontainmentdesignexternalpressureofactuatingthecontainmentsprays(pp.190-195of5/27/82transcript).II.Assessment/ResonseDuringnormaloperation,theonlywaytocreateaconditionoflowairmassinthecontainmentistoventthecontainmentfollowingasteamleak,poolheatuporlossofdrywellcoolingwhichincreasesthecontainmenttemperatureandvaporpressure.Asdescribedintheresponseto8.2,rapidcooldownoftheSSEScontainmentduringnormaloperationwillnotresultinthefinalcontainmentpressureexceedingthe-5.0psigdesignpressure.SincetheTechnicalSpecificationslimitthemaximumpooltemperatureto120'Fandthedrywelltemperatureto135'F,conditionswhichresultinalowercontainmentairmassthantheaboveanalysiscouldnotexist.Furthermore,theresponseto8.2indicatedthataninadvertentsprayactuateduringnormaloperationishighlyunlikely.FollowingaLOCA,theStandbyGasTreatmentSystem(SGTS)usedtoventthecontainmentisolatesonhighdrywellpressure.Post-accidentcontainmentventingwouldonlyoccurtorelievethecontainmentpressureintheeventofimminentcontainmentfailure.Inaddition,FSARSubsection6.2.1.1.4documentedtheSSES-uniquepost-LOCAinadvertentsprayactuation(ISA)transient.Thisanalysisprovidedthebasisforthenumberandflowcapacityofourdrywell-to-wetwellVBstolimitthecontainmentpressureresponsetolessthanthe-5.0psigdesignpressure.Theanalysisassumedallthenon-condensablesinthedrywellwerepurgedintothewetwellairspace,withsteamonlyinthedrywell.Ourreviewofthepost-LOCAISAanalysisindicatedthataninitialpressureof0.1psig(seeFSARTable6.2-23)wasassumed,whiletheTechnicalSpecificationsallowacontainmentpressureequalto-1.0psig.However,were-analyzedthepost-LOCAISAanalysiswithaninitialpressureequalto-1.0psig,anddeterminedthenegativepressuretransientdoesnotexceedthe-5.0psigdesignpressure.Inaddition,theBWROG'sEPGprogramaddressesthecriteriaforoperatoractionstopreventexceedingthecontainmentnegativedesignpressureforabnormalplantconditionsoutsidetheTechnicalSpecificationlimits.TheseguidelinesarecontainedinRevision2oftheEPGs.III.FutureActionReuiredNone-48-Et,tr~,f I.Issue9.FinalDrellAirMass9.1ThecurrentFSARanalysisisbaseduponcontinuousinjectionofrelativelycoolECCSwaterintothedrywellthroughabrokenpipefollowingadesignbasisaccident.SincetheoperatorisdirectedtothrottleECCSoperationtomaintainthereactorvesselwaterleveltoaboutthelevelofthesteamlines,thebreakwillbereleasingsaturatedsteaminsteadofreleasingrelativelycoolECCSwater.Therefore,thedrywellairwhichwouldhavebeenpurgedandthendrawnbackintothedrywellwillremaininthewetwell,andhigherpressuresthananticipatedwillresultinboththewetwellandthedrywell.II.Assessment/ResonseAspreviouslydiscussedin4.4,theshort-termpressureresponsetoaDBALOCAcontrolsthemaximumcontainmentpressure,asopposedtoaMarkIIIcontainmentdesign,wherethelong-termpressureresponseyieldsthemaximumpressure.Therefore,anyECCSthrottlingwhichpreventsvacuumbreakeractuationwillhavenoeffectontheshort-termpressure~~response.III.FutureActionReuiredNone-49-(JP I.Issue9.2ThecontinuoussteamingproducedbythrottlingtheECCSflowwillcauseincreaseddirectleakagefromthedrywelltothecontainment.Thiscouldresultinincreasedcontainmentpressure.II.Assessment/ResonseTheSSES-uniquesteambypasscalculationdescribedintheresponseto5.1assumedacontinuoussteamsupplyfromthedrywell,atadrywell-to-wetwellAPequaltothedowncomersubmergencefortheentiretransient.Therefore,thesteambypassanalysisaccountsforanyincreaseddirectleakage'romthedrywell-to-wetwellcausedbythrottlingtheECCSflow.Inaddition,theanalysisshowedthatoncetheoperatorinitiatescontainmentspray,thepressureincreaseterminates.Theresponsesto4.8and4.9documentedthatnoadverseeffectsontheSSEScontainmentdesignoccurduringoperationofthecontainmentsprays.III.FutureActionReuiredNone-50-I.Issue9.3ItappearsthatsomeconfusionexistsastowhetherSBAsandstuckopenSRVaccidentsaretreatedastransientsordesignbasisaccidents.Clarifyhowtheyaretreatedandindicatewhethertheinitialconditionsweresetatnominalorlicensingvalues(pp.202-205of5/27/82transcript).II.Assessment/ResonsehAppendixIoftheSSESDARdocumentedtheSBAandstuckopenreliefvalvetransients.Theassumptionsusedinthesub)ectanalysisweredevelopedwithintheMarkIIOwners'roupandconformtotherequirementsofdraftNUREG-0783.SupplementNo.1oftheSSESSafetyEvaluationReportdocumentedyourreviewandacceptanceoftheanalysis.III.FutureActionReuiredNone-51-lH<ic(1I'l4iS I.Issue10.1and10.2II.Assessment/ResonseTheNRCdispositionedtheseconcernsasN/AtoSSES.III.FutureActionReuired'one-52-I.Issue,11.0erationalControlofDrelltoContainmentDifferentialPressuresMarkIIIloaddefinitionsarebaseduponthelevelsinthesuppressionpoolandthedrywellweirannulusbeingthesame.TheGGNStechnicalspecificationspermitelevationdifferencesbetweenthesepools.Thismayaffectloaddefinitionforventclearing.Footnote8:ForMarkIandIIfacilities,considerthewaterinthedowncomers.II.Assessment/ResonseThewatergetloadsoccurringduringthewaterclearingphaseofthepoolswellphenomenonareobtainedusingthemaximumwaterclearingvelocity.Thepermissibledifferenceinwaterelevationfrom'thenominalvalueinthesuppressionpoolandthedowncomersare+1ft(VBsetpointequalto0.5psid).Thiselevationdifferencegeneratesasmalldifferenceinbackpressure,whichhasbeenshowntohavenegligibleeffectoneitherventclearingorpoolswellloads.III.FutureActionReuiredNone-53-II(lJ I.Issue12513II.Assessment/ResonseTheNRCdispositionedtheseconcernsasN/AforSSES.III.FutureActionReuiredNone-54-AI I.Issue14.RHRBackflowThrouhContainmentSraAfailureinthecheckv'alveintheLPCIlinetothereactorvesselcouldresultindirectleakagefrom'thepressurevesseltothecontainmentatmosphere.ThisleakagemightoccurastheLPCImotor-operatedisolationvalveisclosingandthemotor-operatedisolationvalveinthecontainmentspraylineisopening.Thiscouldproduceunanticipatedincreasesinthecontainmentspray.II.Assessment/ResonseOperationofthedrywellspraysisnotautomaticandrequiresoperatoractiontoinitiate.TheRHRoperatingprocedurerequirestheLPCIinjectionvalvetothevesseltobeclosedandpermissionfromtheShiftSupervisorpriortoopeningthetwoisolationvalvestothedrywellsprays.Inaddition,theLPCIinjectionvalvesareinterlockedsuchthattheywillnotopenuntilthereactorpressuredecreasesbelow430psig.Atthislowreactorpressure,noappreciableflowfromthereactortothespraysviathefailedcheckvalvecouldoccurunlesstheRHRpumptripped.Thus,operatorerrorandtwosinglefailures(failedcheckvalveandpumptrip)arerequiredtoestablishflowfromthevesseltothesprayheader.ThisscenarioexceedsthedesignbasisoftheSSESplant.III.FutureActionReuiredNone-55-i,pIII'4,I~ I.Issue15.SecondarContainmentVacuumBreakerPlenumResonseTheSTRIDEplantshad.vacuumbreakersbetweenthecontainmentandthesecondarycontainment.Withsufficientlyhighflowsthroughthevacuumbreakerstocontainment,vacuumcouldbecreatedinthesecondarycontainment.II.Assessment/ResonseForSSES,therearenoVBsbetweentheprimarycontainmentandsecondarycontainment.III.FutureActionReuiredNone-56-i~a~~,~i0'4 I.Issue16.EffectofSuressionPoolLevelonTemeratureMeasurementSomeofthesuppressionpooltemperaturessensorsarelocated(byGErecommendation)3into12inbelowthepoolsurfacetoprovideearlywarningofhighpooltemperature.However,ifthesuppressionpoolisdrawndownbelowthelevelofthetemperaturesensors,theoperatorcouldbemisledbyerroneousreadingsandrequiredsafety,actioncouldbedelayed.II.Assessment/ResonseTheSSESSuppressionPoolTemperatureMonitoringSystem(SPOTMOS)has16sensorsat8locations(2perdivision)atEl.20ft.Inaddition,4moresensorsarelocatedatEl.3.5ft(T-quencherelevation).Thecontrolroompaneldisplaystheaverageofthe8uppersensors;butthepooltemperaturesfromthe4lowersensorscanbedisplayed,ifrequired.TheTechnicalSpecificationsrequireasuppressionpoollevelbetween22and24ft.AnalarmsoundsinthecontrolroomifthepoolleveldropstoEl.22.25'.EmergencyoperatingprocedureE0-00-23,"ContainmentControl,"instructstheoperatortorestorethesuppressionpoolleveltobetween22and24ftpertheTechnicalSpecifications.TheMassandEnergyanalysis(seeAppendixIoftheDAR)requirestheoperatortoscramthereactoratapooltemperatureof110'Fanddepressurizethereactoratapooltemperatureof120'F.Thesescenarios(i.e.,isolation/scram,stuckopenreliefvalveandsmallbreakaccident)resultinanincrease,notadecrease,inpoollevelduetocombinationsoffeedwater,HPCI,RCICandroddriveflowfromthecondensatestoragetank.Largebreaks,ontheotherhand,coulddecreasethelevelinsuppressionpool.However,ifthebreakoccurredattheTechnicalSpecificationsminimumlevelof22ft,amaximumdecreaseinpoollevelof1.5ftcorrespondingtothe1.5fttallventrisersinthedrywellwouldstillresultinsubmergeduppersensors.Depressurizingthereactorviathealternatemodeofshutdowncoolingcouldreducethesuppressionpoolleveltobelowtheupper16sensors.Again,theoperatorisinstructedtorestorethesuppressionpoollevelviathecondensatestoragetank.Iflevelcannotberestored,the4lowersensorsandthetemperaturesensoratthesuctiontotheRHRheatexchangerscouldbeusedtomonitorthesuppressionpooltemperature.III.FutureActionReuiredNone-57-Jr I.Issue17.EmerencProcedureGuidelinesTheEPGscontainacurvewhichspecifieslimitationsonsuppressionpoollevelandreactorpressurevesselpressure.Thecurvepresentlydoesnotadequatelyaccountforupperpooldump.Atpresent,theoperatorwouldberequiredtoinitiateautomaticdepressurizationwhentheonlyactionrequiredistheopeningofoneadditionalSRV.II.Assessment/ResonseSSESTechnicalSpecificationsrequirethatthepoollevelbemaintainedwithin'thenormaloperatinglimi'ts'(22to24ft).Iftheycannotberestoredwithin1hour,thentheoperatorisrequiredtobeinhotshutdownwithinthenext12hoursandincoldshutdownwithinthefollowing24hours.Inaddition,emergencyprocedure.E0-00-023,"ContainmentControl,"directstheoperatortomaintainthereactorpressureandpoollevelbelowtheSuppressionPoolLoadLimit(seefigurenextpage),ifthelevelexceeds24'.ThiscanbeaccomplishedbymanuallyactuatingoneormoreSRV,however,ifthelevelandpressurecannotbemaintainedbelowthecurve,thentheoperatorisinstructedtoinitiateADS.III.FutureActionReuiredNone-58-4AttachmentFEO-00-023Revision1Page15of18SUPPRESSIONPOOLLOADLIMITI~'IijII!I~)i~s~>hh~~I)II!!Ir)!I'!(IIRIa.~lIi'.!IIIIiIII'.I!II)~II'.I)III',):I!)iIIII!III}!.iiII;)iI)IIiIIii:!I!)I1}!!!)!!~1IIIIIIIjIIIi.'!IIIIIII!I')IyIIIIII'!)I~IIl!IIII')!II~I~)IjjII!I)I~!~'~jiIis~!I~I~)I~:!II~~'I,0-';'I;200;-,400,.j,I600.,":800,.1000;1'200,,1400.IIIPVPressure(ps20-.I"I!II)~j)Page1of1

I.Issue18.EffectsofInsulationDebris18.1Failuresofreflectiveinsulationinthedrywellmayleadtoblockageofthegratingsabovetheweirannulus.Thismayincreasethepressurerequiredinthedrywelltoclearthefirstrowofdrywellventsandperturbtheexistingloaddefinitions.Footnote10:ThisissueasphrasedappliedonlytoaMarkIIIfacility.However,theconcerncanbegeneralized.Accordingly,discusshowtheeffectsofinsulationdebriscouldperturbexistingloaddefinitionsorcouldblocksuctionstrainers.Inrespondingtothisissue,youmayrefertoexistinggenericstudies,e.g.,thestudydonefortheCooperfacility.II.Assessment/ResonseForSSES,thepeakdownwardpressureonthediaphragmslaboccursduringventclearingatapproximately1secafterthebreak.Thisisinsufficienttimeforanyinsulationdebristotransittoandblockthedowncomers.Subsequenttotheinitialpressurization,anyminorblockagethatmightoccurwouldhaveaninsignificanteffectonpoolswellandthepeakdrywellpressure(seeresponsetoIssue18.2fordescriptionoftheinsulation).III.FutureActionReuiredNone-59-CI I.Issue18.2Insulationdebrismaybetransportedthroughtheventsinthedrywellwallintothesuppressionpool.Thisdebriscouldthencause,blockageofthesuctionstrainers.',Footnote10:ThisissueasphrasedappliesonlytoaMarkIIIfacility.However,theconcerncanbegeneralized.Accordingly,discusshowtheeffectsofinsulationdebriscouldperturbexistingloaddefinitionsorcouldblocksuctionstrainers.Inrespondingtothisissue,youmayrefertoexistinggenericstudies;e.g.,thestudydonefortheCooperfacility.II.Assessment/ResonseThisissueisdiscussedinFSARSection6.2.2.3(inresponsetoNRCQuestion021.20)andissummarizedasfollows:Theinsulationusedwithinthecontainmentistheallmetal,reflectivetype.Theinsulationconsistsoflargeassembliesheldinplacebystainlesssteellatches.Thelatchesareequippedwithpositivelockingdevices.Itwouldbeunlikelythattherelativelylargerpiecesofmetallicinsulationwouldpassthroughthesmallopeningsatthetopofthe87downcomers.TheseopeningsaremadesmallerbythepresenceofjetdeflectorsasshowninFSARFigure6.2-56.,Verylittle,ifany,oftheinsulationwouldfinditswayintothesuppressionpool.ThesuctionstrainersoftheECCSpumpsaredesignedtosustain50%cloggingwithoutaffectingsystemperformance.InadditiontotheFSARdiscussionabove,itshouldbenotedthatthesuctionstrainersarelocatedmidwayupthesuppressionpoolwall.Sinceanymetallicinsulationenteringthepoolwilleitherfloatorsink,thelikelihoodofanystrainercloggingisextremelyremote.III.FutureActionReuiredNone-60-0 I.Issue21.ContainmentMakeuAirForBackuPureRegulatoryGuide1.7requiresabackuppurgeH2removalcapability.Thisbackup~purgeforMarkIIIisviathedrywellpurgelinewhichdischargestotheshieldannuluswhichinturnisexhaustedthroughthestandbygastreatmentsystem(SGTS).Thecontainmentairisblownintothedrywellviathedrywellpurgecompressortoprovideapositivepurge.Thecompressorsdrawfromthecontainment;however,withouthydrogenleanairmakeuptothecontainment,noreductionincontainmenthydrogenconcentrationoccurs.Itisnecessarytoassurethattheshieldannulusvolumecontainsahydrogenleanmixtureofairtobeadmittedtothecontainmentviacontainmentvacuumbreakers.ForMarkIandIIfacilities,discussthepossibilityofpurgeexhaustbeingmixedwiththeintakeairwhich,replenishesthecontainmentairmass.Assessment/Resonse(IntheSSESdesignthepurgeexhauststhroughtheSGTSsystemandexitsonthewestsideofthereactorbuildingroof(El.872').ThesupplyintakeislocatedontheeastsideofthereactorbuildingatapproximatelyEl.790',andthereactorbuildingis160'ide.Basedonthisseparation,exhaustairshouldnotmixwithintakeair.III.FutureActionReuiredNone 4I4tP)Il'H I.Issue22.MiscellaneousEmerencProcedureGuidelineConcernsTheEPGscurrentlyinexistencehavebeenpreparedwiththeintentofcopingwithdegradedcoreaccidents.Theymaycontainrequirementsconflictingwithdesignbasisaccidentconditions.SomeoneneedstocarefullyreviewtheEPGstoassurethattheydonotconflictwiththeexpectedcauseofthedesignbasicaccident.II.Assessment/Resonse-TheSSESEmergencyOperatingProcedureshavebeendevelopedinaccordancewiththeBWROwners'roupEPGs.Assuch,theseguidelinesunderwentarigorousreviewwithinGEand,theOwners'roup.ThisprocessassuredthepreparationofEPGswhichwillrespondto,andmitigate,anyscenarioswhichresultindegradedplantconditions.III.FutureActionReuiredNonePF:sahF 62- %1PlN0 }}