ML17329A690

LER 91-007-01:on 910802,flowpath Identified Which Could Result in Diversion of Water Away from ECCS & Containment Bldg.Caused by Erroneous Steps in Eop.Eop Revised W/ Assistance of Westinghouse.W/921124 Ltr

ML17329A690
Person / Time
Site:	Cook
Issue date:	11/24/1992
From:	BLIND A A, SAMPSON J R INDIANA MICHIGAN POWER CO. (FORMERLY INDIANA & MICHIG
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
LER-91-007-01, LER-91-7-1, NUDOCS 9212010289
Download: ML17329A690 (9)

Text

ACCeCE<<'i'SU0'TMOUTIONDEMONTRACTIONSYSTEMlREGULATOINFORMATIONDISTRIBUTIONTEM(RIDS).ACCESSIONNBR:9212010289DOC.DATE:92/11/24NOTARIZED:NODOCKETFACIL:5fI-316DonaldC.CookNuclearPowerPlant,Unit2,IndianaM05000316AUTH.NAMEAUTHORAFFILIATIONSAMPSON,J.R.IndianaMichiganPowerCo.(formerlyIndiana8MichiganEleBLIND<A.A.IndianaMichiganPowerCo.(formerlyIndiana6MichiganEleRECIP.NAMERECIPIENTAFFILIATION

SUBJECT:

LER91-007-01:on910802,identifiedflowpaththatdivertedECCSflowcausedbyplantdesign/emergencyresponseguidelines.ReviewedplantspecificEOPstoensurethatproceduresareprovidedtoplantoperators.W/921124ltr.DISTRIBUTIONCODE:ZE22TCOPIESRECEIVED:LTR(ENCLUSIZE:TITLE:50.73/50.9LicenseeEventReport(LER),IncidentRpt,etc.NOTES:RECIPIENTIDCODE/NAMEPD3-1LADEANIWINTERNAL:ACNWAEOD/DSP/TPABNRR/DET/EMEB7ENRR/DLPQ/LPEB10NRR/DREP/PRPBllNRR/DST/SICB8H3NRR/DST/SRXB8ERES/DSIR/EIBEXTERNAL:EG&GBRYCEsJ.HNRCPDRNSICPOOREEW.COPIESLTTRENCL11112211111122111111221111RECIPIENTIDCODE/NAMEPD3-1PDAEOD/DOAAEOD/ROAB/DSPNRR/DLPQ/LHFB10NRR/DOEA/OEABNRR/DST/SELB8DNRR/DSTSPLB8D1'E02RGN3FILE01LSTLOBBYWARDNSICMURPHYEG.ANUDOCSFULLTXTCOPIESLTTRENCL111122111111111111111111NOTETOALL"RIDS"RECIPIENTS:PLEASEHELPUSTOREDUCEWASTE!CONTACTTHEDOCUMENTCONTROLDESK.ROOMPl-37(EXT.504-2065)TOELIMINATEYOURNAMEFROMDISTRIBUTIONLISTSFORDOCUMENTSYOUDON'TNEED!FULLTEXTCONVERSIONREQUIREDTOTALNUMBEROFCOPIESREQUIRED:LTTR29ENCL29 IndianaMichiganPowerCompanyCookNuclearPianiOneCookPlaceBridgman,Mi491066164655901November24,1992lNOlANANlCHlGANPOWMUnitedStatesNuclearRegulatoryCommissionDocumentControlDeskRockville,Maryland20852OperatingLicensesDPR-74DocketNo.50-316DocumentControlManager:Inaccordancewiththecriteriaestablishedby10CFR50.73entitledLicenseeEventReortSstemthefollowingreportisbeingsubmitted:91-007-01Sincerely,A.A.BlindPlantManager/sbAttachmentc:D.H.Williams,Jr.A.B.Davis,RegionIIIE.E.FitzpatrickP.A.BarrettR.F.KroegerB.Walters-Ft.WayneNRCResidentInspectorW.M.Dean-NRCJ.G.KepplerM.R.PadgettG.Charnoff,Esq.D.HahnINPOS.J.BrewerB.A.Svensson9212010289921124PDRADOCK050003168PDRiongji1' NRCFORM355(54)9)APPROVEDOMBNO.3(504104EXPIRES:4/30/92ESTIMATEDBURDENPERRESPONSETOCOMPLYWTHTHISLICENSEEEVENTREPORT(LER)COMMENTSREGARDINGBURDENESTIMATETOTHERECORDSINFORMATIONCOLLECTIONREOUEST!50.0HRS.FORWARDANDREPORTSMANAGEMENTBRANCHIP.530),U.S.NUCLEARREGULATORYCOMMISSION.WASHINGTON,DC20555,ANDTO1THEPAPERWORKREDUCTIONPROJECT(31500104I.OFFICEOFMANAGEMENTANDBUDGET,WASHINGTON,DC20503.FACILITYNAMEIllD.C.CookNuclearPlant-Unit2DOCKETNVMBER(2)PAE3osooo316ioFOSimulatorScenarioIdentifiedFlowpaththatDivertedECCSFlowCausedbPlantDesign/EmergencyResponseGuidelinesMONTHDAYYEAREVENTDATE(51YEARLERNUMBKRIB)SNOUSNTIALNUMSER?errRKVrSIONNUMB5tlREPORTDATE(7)MONTHDAYYEAROTHERFACILITIESINVOLVED(~IDOCKETNUMBER(SIosooo315FACILITYNAMESD.C.Cook-Unit1080291910070111249?05000OPERATINGMODE(4)POWERLEvEL00020A02(b)20AOB(~I(II0)20AOB(rill)INI20.405le)(1)(IN)20A054)Ill(ir)20AOB(oIII)lrl20.405(cl50.35(cl(II50.35(cl(2I50.734)(2)(I)5023(ol(2)(NI50.'73(oI(2)(NIILICENSEECONTACTFORTHISLER(12I50.73lolCI)(ir)50,73(~)(2)lrl50.73(ol(2)(rN)50.73(o)(21(riN)(AI50.73(oN1(lriN)(BI50.73(~l(2((clTHISREPORTISSUBMITTEDPURSUANTT0THERNOUIREMENTBoF10cFR(It(chocoonoormorooitnofortowins)(1173.71(III73.71(c)OTHERISpocityinAbrtroctbelowonyinToot.HRCFormSEEAINAMEJ.R.Sampson,OperationsSuperintendentTELEPHONENUMBERAREACODE616465-5901COMPLETKONELINEFOREACHCOMPONENTFAILUREDESCRIBEDINTHISREPORT(13)CAUSESYSTEMCOMPONENTMANUFACTUREREPORTABLE)SIP.Y~A:Spic.TONPRDS'~Pi~.'~>.~i'o'AUSESYSTEMCOMPONENTMANUFACTURERTONPRDS('k/p~+)@~ZANrra~~@SVPPLEMENTALREPORTEXPECTED(14)YEBIifyor,completeExpEcTEDsvEbrlssloHDATEINOABSTRACTILimittoteOOooocor,ie.,ooprooimMoly!if!tenoinoletpocotypewrittenIinai(15)EXPECTEDSUBMISSIONDATE(15)MONTHOAYYEARThisupdateisbeingsubmittedtopresentthereviewconductedbytheWestinghouseCorporation.On8-2-91,a"smallbreaklossofcoolantaccident"runonthePlantsimulatoridentifiedaflowpathwhichmaybeestablishedbyplantconditionsandtheEmergencyOperatingProcedures(EOPs)withthepotentialtodivertwaterawayfromtheemergencycorecoolingsystemandthecontainmentbuilding.TheflowpathwasfromtheCentrifugalChargingPumpdischargethroughanemergencyleakoffvalve,throughthesealreturnlinesafetyvalvetothevolumecontroltank(VCT),andthroughtheVCTsafetyvalvetothechemicalandvolumecontrolsystemholduptanks.Areviewofthefindingconcludedthattheamountofwaterwhichcouldbediverteddidnotsignificantlyaffectcorecooling.However,thedivertedwaterwouldbedischargedfromthecontainmentbuilding.Analysisofthepotentialdoseratefromthedivertedwatertothewholebodyatthesiteboundarywascalculatedtobeinsignificantcomparedtothe10CFR100accidentdoselimitandevenwithinthe10CFR20.105doselimitsforunrestrictedareasduringnormaloperations.TheconditionidentifiedhasthepotentialtobeagenericissueforWestinghouse-designedplants.TheappropriateEOPwasrevisedtoaddressthesimulatorfindings.NRCForm345(54)9)

NRCFORM366A(6J)9)U.S.NUCLEARAEGULATOAYCOMMISSIONLICENSEEEVENTREPORTILER)TEXTCONTINUATIONAPPROVEDOMBNO.3)500106EXPIRES:SI30l92ESTIMATEDBURDENPERRESPONSETOCOMPLYWTHTHISINFORMATIONCOLLECTIONREQUEST:50.0HRS.FORWARDCOMMENTSREGARDINGBURDENESTIMATETOTHERECORDSANDAEPOATSMANAGEMENTBRANCHIP530).U.S.NUCLEARREGULATORYCOMMISSION,WASHINGTON.DC20555,ANDTOTHEPAPERWORKREDUCTIONPROJECT(3)50s)loa).OFFICEOFMANAGEMENTANDBUDGET,WASHINGTON.DC20503.FACILITYNAME(1)DOCKETNUMBERl21YEARLERNUMBER(6)SEOUENTIALNUMOERREVISIONNUMEERI'AGEl3)D.C.CookNuclearPlant-Unit2TEXTIIImoIeSpaceISscow'rNSII>>ed(so'opalHRCFomI36SA's)(17)o5ooo316910070102oF06ConditionsPriorToOccurenceUnitone(U-1)inmodeoneat100Xpower.Unittwo(U-2)inmodethree(hotstandby).DescritionofEventOn8-2-91,whiletheTrainingDepartmentwasrunningasmallbreaklossofcoolantaccident(LOCA)onthePlantsimulator,aflowpathwasidentifiedwhichcouldresultinthediversionofwaterawayfromtheemergencycorecoolingsystem(ECCS)(EIIS/BQ)andthecontainmentbuilding(EIIS/NH).Descriptionofsystems(referenceFigure1):Uponreceiptofasafetyinjectionsignal(EIIS/JE-ACO),thesafetyinjectionsystem(SIS)centrifugalchargingpump(CCP)(EIIS/BQ-P)suctiontransfersfromthevolumecontroltank(VCT)(EIIS/CB-TK)totherefuelingwaterstoragetank(RWST)(EIIS/BP-TK).TheCCPemergencyleakoffs(ELO)isolationvalves(EIIS/BQ-LOV)closeandthenreopeniftheReactorCoolantSystem(RCS)pressureincreases'ogreaterthan2000psi.IftheaccidenthasprogressedtothepointofswitchoverfromtheRWSTtothecontainmentrecirculationsump(EIIS/NH-RVR),theCCPsuctionisrealignedtothedischargeoftheresidualheatremoval(RHR)pumps(EIIS/BP-P).WiththeRHRpumpsupplyingthesuctiontotheCCP,theCCPsuctionpressurecouldbeashighas205psig(RHRpumpshutoffheadpressure).SincethesuctiontotheCCPissuppliedbythedischargeoftheRHRpumpandtheCCPELO(ifopened)isreturnedtothesuctionofthepump,thepressureintheELOlinecouldbeinexcessofthe150psigpressuresetpointforsafetyvalveSV-54(EIIS/CB-RV)locatedupstreamofthesealwaterheatexchanger(EIIS/CB-HX).IfSV-54liftsandoneCCPisinoperation,thenapproximately60gpmflowwouldbedivertedfromtheEmergencyCoreCoolingSystem(ECCS)intotheVCT.Ifnotterminated,theVCTwouldfillandthenlifttheVCTsafetyvalveSV-53(EIIS/CB-RV).SV-53issetat75psigandwilldivertflowtothechemicalandvolumecontrolsystem(CVCS)holduptanks(EIIS/WD-TK).NRCForm366A(669)

NRCFORMSSBA(6()91US.NUCLEARREGULATORYCOMMISSIONLICENSEEEVENTREPORTILER)TEXTCONTINUATIONAPPROVEO0MBNO.31504)OS5XPIRES:S/30/92ESTIMATEDBURDENPERRESPONSETOCOMPLYWTHTHISINFORMATIONCOLLECTIONREQUEST:508)HRS.FORWARDCOMMENTSREGARDINGBURDENESTIMATETOTHERECORDSANDREPORTSMANAGEMENTBRANCH(P-530),U.S.NUCLEARREGULATORYCOMMISSION,WASHINGTON,DC20555.ANDTOTHEPAPERWORKREDUCTIONPROJECT(3150410SI,OFFICEOFMANAGEMENTANOBUDGET,WASHINGTON,OC20503.FACILITYNAME(1)DOCKETNUMBER(2)LERNUMBERLB)YEARLyL~sSSOUSssTIAL~AEYSIONssUMos4oNUMosRPAGE(3)D.C.CookNuclearPlant-Uni.t2TEXT///mossssssoisrrquirat,osssddkbrul/t/RCFoms3555's/(17)0500031691007-0103oF06CauseofEventThepotentialdivertflowpathidentifiedbythesimulatorscenariowascausedbystepsintheEmergencyOperatingProcedure(EOP).TheEOPinstructstheoperatorstoopentheCCPELOisolationvalvesinpreparationforswitchoveroftheCCPdischargefromtheECCSlineupthroughtheboroninjectiontank(BIT)(EIIC/BQ-TK)tothenormalchargingdischargelineup.TheEOPstepstoresetandopentheCCPELOvalvesinpreparationfortheswitchoverofthepumpdischargetothenormallineuparebasedontheEOPWestinghouseOwnersGroup(WOG)EmergencyResponseGuidelines(ERG).TheEOPERGstatesthattheELOshouldbereestablishedbeforetheBITisisolated.TheaffectsofthisELOalignmentintheabovedescribedPlantconditionwerenotpreviouslyrecognizedbytheCookNuclearPlantdesignandsafetyvalvesetpointsreview.AlthoughnotdiscussedintheWestinghouseletter,AmericanElectricPowerServiceCorporation(AEPSC)hasbeeninformedbyWestinghousethatitisnotpossibletoconcludepositivelythattheRCSwillbebelow2000psibythetimeofswitchovertorecirculation.Thismaybeespeciallytrueforicecondenserplants,becausethelowercontainmentsprayinitiationsetpointforicecondenserplantsmakesitmorelikelythatcontainmentspraywillbeactivatedresultinginmorerapiddepletionoftherefuelingwaterstoragetank.AnalsisofEventThisconditionisbeingreportedinaccordancewith10CFR50.73(a)2(ii)(B)asaconditionoutsideofthedesignbasisoftheCookNuclearPlant.FollowingareviewofthefindingsofthisLER,ithasbe'enconcludedthattheamountofwaterdivertedfromtheECCSisnotconsideredtobesignificant,basedonthefollowing:InordertoestablishthenormalCCPdischargelineuppertheEOP,theRCSinventorycontrolmustbemanageablewiththeconditionsdescribedintheinvestigationsectionofthisreport.2.Inaddition,undertheconditionsdescribed,theRCScooldownwouldbeprogressinginpreparationforplacingtheRHRsinservicefordecayheatremovalandcooldown.NRCFosso366A(689)

NACFORM368A(689)U.S.NUCLEARREGULATORYCOMMISSIONLICENSEEEVENTREPORT(LER)'EXTCONTINUATIONAPPROVEO0MBNO.31504104EXPIRES;4)30)92ESTIMATEDBURDENPERRESPONSETOCOMPLYWTHTHISINFORMATIONCOLLECTIONREQUEST:600HRS.FORWARDCOMMENTSREGARDINGBUADENESTIMATETOTHERECORDSANOREPORTSMANAGEMENTBRANCH(F430).U.S.NUCLEARAEGULATORYCOMMISSION.WASHINGTON,DC20555,ANDTOTHEPAPERWOAKREDUCTIONPROJECT(31500104),OFFICEOFMANAGEMENTANDBUDGET,WASHINGTON,OC20503.FACILITYNAME111DOCKETNUMBERLTILERNUMBER(6)PAGE(3)YEAR9%SEDVENTIALNVMSEIIII8VISIONIIUMFSIID.C.CookNuclearPlant-Unit2TEXT/IImoroz>>coisnJrrr)orLosoorssisior>>JHRCFarm3IJSA'4)(IT)osooo316910070104OF063.Also,consideringthattheflowratedivertedfromthesumpisestimatedtobeabout60gpm,theflowdivertedisconsideredsmallinrelationto,thetotalvolumeofwaterexpectedtobeinthesump(wellinexcessof255,000gallons).ThisvolumeinthecontainmentsumpisconsideringthestableconditionexpectedfortheECCSandRCSatthetimeoftheCCPdischargerealignment.AlthoughtheamountofwaterdivertedfromtheECCSisnotconsideredtobesignificantfromacorecoolingperspective,thedivertedwaterdoesrepresentaconditionwherebycoolantisbeingdischargedfromthecontainmentbuilding.Therefore,thedivertedwaterisconsideredtobeaconditionoutsideoftheCookNuclearPlantdesignbasis.Ananalysisofthepotentialdoseconsequencesofthisconditionwasperformed.Theanalysisassumeda10gpmleakfromtheVCTorCVCSholduptanksand1Xfailedfuelrecirculationcoolantactivity.Withtheassumedstatedconditions,thewholebodydoserateatthesiteboundarywasdeterminedtobeonly0.293mR/hr.Thisisinsignificantcomparedtothe10CFR100accidentdoselimitandisevenbelowthe10CFR20.105doselimitsforunrestrictedareasduringnormaloperation.rWestinghouse'sreviewofthisissueresultedinadeterminationthatforasmallbreak(2'inches)thatmayallowtheRCStoremainatanelevatedpressure,theflowoutthebreakisexpectedtobesufficienttoprecluderepressurizingtheRCSabove2,000psig.ForsmallerbreakswhereRCSrepressurizingmayoccur,theoperatorisexpectedtoterminatesafetyinjectionbeforechargingpumpdeadheadingcouldoccur.Additionally,Westinghousereviewedaconcernforadequatechargingflowwiththe'miniflowisolated.Breaksizesneededtoresultinchargingflowbelowthatrequiredforadequatecoolingwerefoundtobelessthan3/8inchindiameter,abreaksizethatisnotconsideredtobeaLOCA.Therefore,WestinghousebelievesthatadequatecoolingofthechargingpumpsduringoperationintherecirculationmodesisassuredunderLOCAconditionswithminiflowisolated.Basedontheaboveanalysis,itisconcludedthattheconditionidentifiedbythissimulatorscenariowouldnotsignificantlyimpactpublichealthandsafety.NRCForm368A(689)

NRCFORM366A(689IUS.NUCLEARREGULATORYCOMMISSIONLICENSEEEVENTREPORTILER)TEXTCONTINUATIONAPPROVED0MBNO.3'I500104EXPIRE5:4/30/92ESTIMATEDBURDENPERRESPONSETOCOMPLYWTHTHISINFORMATIONCOLLECTIONREOUESTI500HRS.FORWARDCOMMENTSREGARDINGBURDENESTIMATETOTHERECORDSANDREPORTSMANAGEMENTBRANCH(F430),U.S.NUCLEARREGULATORYCOMMISSION,WASHINGTON.OC20555.ANDTOTHEPAPERWORKREDUCTIONPROJECT(31500104I.OFFICEOFMANAGEMENTANDBUDGET,WASHINGTON,DC20503.FACILITYNAME(I)DOCKETNUMBER(2)YEARLERNUMBER(6)SEOUENTIALNUMOERREVISIONNUMBERPAGE(3)D.C.CookNuclearPlant-Unit2TEXTll!morospscois/squi/od,usoodddlo/N/ill/CFom/3664'4/((7)0so0o316910070105QF06CorrectiveActionsByletterdatedNovember3,1992,WestinghousenotifiedpotentiallyaffectedlicenseesoftheresultsoftheirreviewoftheissuesdiscussedinouroriginalLERsubmittal.Althoughlicenseeswerenotifiedoftheissue,Westinghouse'sevaluationconcludedthatthesituationdoesnotrepresentaSubstantialSafetyHazardorFailuretoComplypursuantto10CFR21.TheaffectedEmergencyOperatingProcedurewasrevisedtocautiontheoperatortoestablishminimumchargingflowtoprotecttheoperatingCCPifcoldlegrecirculationhasbeeninitiated,andtoverifyproperoperationoftheCCPemergencyleakoffvalves,duringSIconditions.TheWestinghouseletterprovidedseveralpotentialmeansforresolvingtheissue.OnespecificoptionwastoreviewplantspecificEOPstoensurethatproceduresareprovidedtoplantoperatorstodepressurizeandcooldownduringapostulatedsmallbreakLOCA,andtomodifytheEOPstoensurethatthechargingpumpminiflowlinesareisolatedduringrecirculation.FollowingconversationswithWestinghousethatprecededreceiptoftheletterdescribedabove,wemademodificationstoourEOPsthatmeettheintentoftheWestinghouserecommendation.TheEOP,ES-1.3(TransfertoColdLegRecirculation)hasbeenmodifiedsuchthatitinstructstheoperatortoopenapressurizerPORV,asnecessary,toreduceRCSpressureandtomaintainminimumchargingpumpflow.Theprocedureinstructstheoperatortoclosethechargingpumpminiflowvalvesaspartoftheswitchoverfrominjectiontorecirculation.(Precautionsareincluded,however,thatinstructtheoperatortoshutoffaredundantchargingpumportoopentheminiflowvalvesifconditionsthatensureadequatepumpprotectionarenotmet.)FailedComonentIdentifiedNonePreviousSimilarEventsNoneNRCFomI366A(64)9)

NRCFORM355A(SS)91U.S.NUCLEARREGULATORYCOMMISSIONLICENSEEEVENTREPORT(LER)TEXTCONTINUATIONAPPROVEDOMBNO.31504)0i5XPIA5SIi/30/92ESTIMATEDBURDENPERRESPONSETOCOMPLYWTHTHISINFORMATIONCOLLECTIONREOUESTI500HRS.FORWARDCOMMENTSREGARDINGBURDENESTIMATETOTHERECORDSANDREPORTSMANAGEMENTBRANCHIP430),U.S.NUCLEARREGULATORYCOMMISSION,WASHINGTON,OC20555.ANDTOTHEPAPERWORKREDUCTIONPROJECT13150410i).OFFICEOFMANAGEMENTANDBUDGET,WASHINGTON,DC20503.FACILITYNAME11)DOCKETNUMBER12)YEARLEANUMBERLE)SEQUENTIALNUMEERREVISIONNUMEERPAGEIS)D.C.CookNuclearPlant-Unit2TEXT///morsspsssisrsr/vtrsrLvsssA//aarM//YRCfarm35EA's/I)7)osooo316910070106OF06FIGURE175kTOCVCSHOLD-UPTAHRSPRONLETDOUHFROMSEALRETURN150fCLOSEDCLOSEDONSIToCHGHEADERELOPROMRHRPUNPSDURINGECCSRECIRC.CHGPUMPSTOBITNRCForm355AISSQ)