ML17229A616

LER 98-001-00:on 980104,inadvertent RPS Actuation Occurred Due to Personnel Error.Caused by Procedural Inadequacies & Inadequate self-checking by Licensed Utility Personnel. Placards Have Been Placed in CRs.W/980203 Ltr

ML17229A616
Person / Time
Site:	Saint Lucie
Issue date:	02/03/1998
From:	FREHAFER K W, STALL J A FLORIDA POWER & LIGHT CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
L-98-018, L-98-18, LER-98-001, LER-98-1, NUDOCS 9802110012
Download: ML17229A616 (7)

Text

CATEGORY1~REGULARLYINFORMATIONDISTRIBUTIOF%YSTEM(RIDS)p)*ACCESSIONNBR:9802110012DOC.DATE:98/02/03NOTARIZED:NOFACIL:50-335St.LuciePlant,Unit1,FloridaPower&LightCo.AUTH.NAMEAUTHORAFFILIATIONFREiIXFER,K.W.FloridaPower&LightCo.-STALL,J.A.FloridaPower&LightCo.RECIP.NAMERECIPIENTAFFILIATIONDOCKET¹05000335

SUBJECT:

LER98-001-00:on980104,inadvertentRPSactuationoccurredduetopersonnelerror.Causedbyproceduralinadequacies&,inadequateself-checkingby.licensedutilitypersonnel.PlacardshavebeenplacedinCRs.W/980203ltr.DISTRIBUTIONCODE:IE22TCOPIESRECEIVED:LTRENCLSIZE:TITLE:50.73/50.9LicenseeEventReport(LER),IncidentRpt,etc.NOTES:'CRECIPIENTIDCODE/NAMEPD2-3PDINTERNAL:ACRSAEOD/SPD/RRABNRR/DE/ECGBNRR/DE/EMEBNRR/DRCH/HICBNRR/DRCH/HQMBNRR/DSSA/SPLBRES/DET/EIBEXTERNAL:LSTLOBBYWARDNOACPOORE,W.NRCPDRCOPIESLTTRENCL111111111111111111111111RECIPIENTIDCODE/NAMEWIENS,L.CgNRRDEEELBNRR/DRCH/HHFBNRR/DRCH/HOLBNRR/DRPM/PECBNRR/DSSA/SRXBRGN2FILEOlLITCOBRYCE,JHNOACQUEENER,DSNUDOCSFULLTXTCOPIESLTTRENCL112211111111111111111111NOTETOALL"RIDS"RECIPIENTS:PLEASEHELPUSTOREDUCEWASTE.TOHAVEYOURNAMEORORGANIZATIONREMOVEDFROMDISTRIBUTIONLIST>>ORREDUCETHENUMBEROFCOPIESRECEIVEDBYYOUORYOURORGANIZATION,CONTACTTHEDOCUMENTCONTROIDESK(DCD)ONEXTENSION415-2083FULLTEXTCONVERSIONREQUIREDTOTALNUMBEROFCOPIESREQUIRED:LTTR25ENCL25 FloridaPower&LightCompany,6351S.OceanDrive,JensenBeach,FL34957February3,1998L-98-01810CFR50.73U.S.NuclearRegulatoryCommissionAttn:DocumentControlDeskWashington,D.C.20555Re:St.LucieUnit1DocketNo.50-335ReportableEvent:98-001DateofEvent:January4,1998InadvertentRPSActuationDuetoPersonnelErrorTheattachedLicenseeEventReportisbeingsubmittedpursuanttotherequirementsof10CFR50.73.Verytrulyyours,J.A.StallVicePresidentSt.LuciePlantJAS/KWFAttachmentcc:RegionalAdministrator,USNRC,RegionIISeniorResidentInspector,USNRC,St.LuciePlant'ir802ii0012'rr80203PDRADQCK050003358PDRllllllllllllllllllllllllllllllllllllllanFPLGroupcompany NRCFORM366(4.9e)U.S.NUCLEARREGULATORYCOMMISSIONLICENSEEEVENTREPORT(LER)(Seereverseforrequirednumberofdigits/charactersforeachbiock)APPROVEDSVOMBNo.S(60<0(O4EXARES04/30/SSESTIMATEDBURDENPERRESPONSETOCOMPLYWITHTHISMANDATORINFORMATIONCOLLECTIONREOUEST:60.0HRS.REPORTEDLESSONLEARNEDAREINCORPORATEDINTOTHEUCENSINGPROCESSANDFEBACKTOINDUSTRY.FORWARDCOMMENTSREGARDINGBURDENESTIMATTOTHEINFORMATIONANDRECORDSMANAGEMENTBRANCH(TWF33(US.NUCLEARREGIAATORYCOMMISSION,WASHINGTON,DC20666ENOIANDTOTHEPAPERWORKREDUCTIONPROJECT(3(600104I,OFRCE0MANAGEMENTANDBUDGET,WASHINGTON,DC20603.FACIUTYNAMEUISTLUCIEUNIT1TITLE(4IInadvertentRPSActuationDuetoPersonnelErrorDOCKETNINVIB(R(2(05000335PAGE(SI1OF4DAYYEAR498YEARSEOUENTIALREVISIONMONTHNUMBERNUMBER98,-001-0OAYYEAR398FACIUTYNAMEFACIUTYNAMEDOCKETNUMBER05000DOCKETNUMBER05000OPERATINQMODE(9)POWERLEVELl10)20.2201(b)20.2203(a)(2)6)20.2203{a)(2)(iii)20.2203(a)(2)(iv)20.2203(a)l2)(v)20.2203(a)(3)(ii)50.36(c)(1)50.36(c)(2)50.73(a)l2){i)50.73(a)(2)(iii)50.73(a){2){v)50.73(a)(2)(vii)50.73{0)l2)(viii)73.71OTHERSpecifyInAbstractbeloworinNRCForm366ANAMEK.W.Frehafer,LicensingEngineerTELEPHONENUMBERSrc(vdeArtaCodel(561)468-4284CAUSESYSTEMCOMPONENTMANUFACTURERREPORTABLETONPRDSCAUSESYSTEMCOMPONENTMANUFACTURERToNPRDSJCN/AN/AN/AYES{Ityes,completeEXPECTEDSUBMISSIONDATE).XNoEXPECTEDSUBMISSIONDATE(15)MONTHOAYYEARABSTRACT(Umitto1400spaces,l.e.,approximately15single-spacedtYpewrittenlines)(16)OnJanuary4,1998,Unit1wasatzeropercentpower,inMode3,withpressurizerpressurelessthan1750psig.Areactorplantheatuptonormaloperatingtemperatureandpressurefollowingrefuelingwasinprogress.Thereactortripbreakerswereclosedandallreactorcontrolelementassemblieswerefullyinserted.Theoperatorsweredirectedtoremovethezeropowermodebypasskeysforeachchannelofthereactorprotectionsystemoncethefourthreactorcoolantpumpwasstarted.Thereactortripbreakersopenedimmediatelyafterthereactorprotectionsystem'C'hannelzeropowermodebypasswasunbypassed.Thiseventwascausedbyproceduralinadequaciesandinadequateself-checkingbylicensedutilitypersonnel.Theproceduredidnotaddressplantconditionsnecessarytoensurethereactorprotectionsystemthermalmarginflowpressuretripsetpointwasbelowactualsystempressurewhenthezeropowermodebypasskeyswereoperated.Duringtheevent,plantconditionswouldhavesetthethermalmargin/lowpressuretripsetpointat1887psia,andactualreactorcoolantsystempressurewasapproximately1740psiawhenthereactorprotectionsystemzeropowermodebypasswasunbypassed.Additionally,theoperatorcontinuedwiththeunbypassingofthezeropowermodebypassanddidnotgivethecrewtimetoreviewthevalidityofthealarmsandensureallconditionsweresatisfactorypriortocompletingtheprocedure.Correctiveactionsincludedproceduralenhancements,counselingtheoperator,andcrewbriefingsontheevent.NRCFORM366{4.9S)

NRCFORM366AI4.9S)LICENSEEEVENTREPORT(LER)TEXTCONTINUATIONU.S.NUCLEARREGULATORYCOMMISSIOST.LUCIEUNIT105000335YEARSEQUENTIALREVISION98-001-02OF4TEXT/ifmorespeceisrequired,useeddidonelcopiesofNRCForm36@A/I17]OnJanuary4,1998,Unit1wasatzeropercentpower,inMode3,withpressurizerpressurelessthan1750psig.AreactorplantheatuptonormaloperatingtemperatureandpressurefollowingrefuelingwasinprogressinaccordancewithNormalOperatingProcedureNOP-1-0030121,"ReactorPlantHeatup-ColdtoHotStandby."ReactorCoolantSystem(RCS)temperaturewasapproximately510'Fandpressurewasapproximately1700psia.ReactorTripCircuitBreakers(TCBs)[EIIS:JC:BKR]wereclosedandallreactorControlElementAssemblies(CEAs)[EIIS:AA]werefullyinserted.ThefourthReactorCoolantPump(RCP)[EIIS:AB:P],1A1,wassuccessfullystartedinaccordancewithstep6.5.12oftheheatupprocedure.Step6.5.13directsanoperatortoremovetheZeroPowerModeBypass(ZPMB)[EIIS:JC:33]keysforeachchanneloftheReactorProtectionSystem(RPS)[EIIS:JC]oncethefourthRCPisstarted.At1050,thereactoroperatorturnedtheZPMBkeyfrombypasstooffforRPSchannel'A'ndtheThermalMargin/LowPressure(TM/LP)triplockedin.Thereactoroperatorcontinued,withtheprocedureandturnedtheZPMBkeyfrombypasstooffforRPSchannels'B','C',and'D'nsequence.ItwasthennotedthattheTCBshadopened,anditwasconfirmedviatheSequenceofEventsRecorder(SOER)[EIIS:IQ]thattheTCBshadopenedimmediatelyafterRPSchannel'C'asunbypassed.TheoperatorsimmediatelyreturnedtheZPMBkeysbacktothebypassposition.ThiseventwascausedbyproceduralinadequaciesinprocedureNOP1-0030121,"ReactorPlantHeatup-ColdtoHotStandby."Inadequateself-checkingbylicensedutilitypersonnelcontributedtothisevent.ProcedureNOP1-0030121,"ReactorPlantHeatup-ColdtoHotStandby,"step6.5.13,directstheoperatorstoplacetheZPMBkeyfrombypasstooffafterthefourthRCPisstarted.However,theproceduredidnotaddressalltripfunctionspotentiallybypassedbytheZPMBkey.TheZPMBswitchisakeyoperatedswitch,oneforeachRPSchannel.TheZPMBallowstheRPSlowflowandTM/LPtripstobebypassedforsubcriticaltestingofcontrolelementdrivemechanisms;ThisRPSbypassisautomaticallyremovedwhenreactorpowerlevelincreasesaboveonepercentpower.ThelowflowtripisprovidedtoprotectthecoreagainstDeparturefromNucleateBoiling(DNB)intheeventofacoolantflowdecrease.Thelowflowtripisafunctionofmeasureddifferential.pressureacrossthesteamgeneratorsandthenumberofoperatingRCPs.NRCFORM366A(4-9S) y1 NRCFORM366AI4.96)LICENSEEEVENTREPORT(LER)TEXTCONTINUATIONU.S.NUCLEARREGULATORYCOMMISSIOST.LUCIEUNIT105000335YEARSEQUENTIALREVISION98-001-03OF4TEXTllfmorespeceisrequired,useedditionelcopiesoffVRCForm3MAII17ICAUSEOFTHEEVENTcont'dTheTIVI/LPtripisprovidedfortwopurposes.Thelowpressurizerpressureportionofthetripfunctionstotripthereactorintheeventofalossofcoolantaccident.Thethermalmarginportionofthetrip,inconjunction.withthelowreactorcoolantflowtrip,isdesignedtopreventthereactorcoresafetylimitonDNBfrombeingviolatedduringanticipatedoperationaloccurrences.TheTM/LPtripsetpointiseitheracalculatedpressurevaluebasedonRCStemperature,powerandflow,oraminimumbiasedpressurevalueof1887psia.Duringtheevent,fourRCPswereoperating(ensuringthatalowflowtripwouldnotbepresent),butexistingplantconditionssettheTM/LPtripsetpointattheminimumbiasedpressurevalueof1887psia,TheZPMBkeyswereplacedfrombypasstooffwhileRCSpressurewasapproximately1740psia,whichresultedintheTM/LPtripandopeningthereactorTCBs.Additionally,personnelerrorbytheoperatorandoperatingcrewresultedinnotinvestigatingthecauseoftheTM/LPalarmswhentheywerereceivedastheRPSchannelZPMBkeysweresequentiallyplacedfrombypasstooff.Theoperatorcontinuedwiththeprocedureanddidnotgivethecrewtimetoreviewthevalidityofthealarmsandensureallconditionsweresatisfactorypriortocompletingtheprocedure.TheTCBsopenedwhenthethirdRPSchannelZPMBkeywasplacedfrombypasstooff,whichcompletedthecoincidencerequirementsfortheTM/LPreactortrip.St.LuciePlantmanagementexpectationsforlicensedoperatorresponsetounexpectedcontrolroomalarmsarethatthelicensedoperatoracknowledgingthealarmannouncethealarmtocontrolroompersonnelas"unexpected,"thatcontrolroomactivitiesstoptopermitinvestigationofthealarm,andthatactionsaretakeninaccordancewithplantalarmresponseprocedurestodeterminethecauseofthealarm.Suchactivitiesdidnotoccurduringthisevent.ThiseventisreportableasavalidactuationoftheRPSper10CFR50.73(a)(2)(iv).SinceremovingthebypassfromtheZPMBrestoredthecapabilityoftheTM/LPtripcircuitrytorespondtoanRCSlowpressurecondition,thiseventisconsideredavalidRPSactuationbasedonactualplantconditions.ItwasreportedtotheNRCasafourhourENSnotificationat1708hoursonJanuary5,1998.ThereactorwasshutdowninHotStandbypriortotheevent.AlthoughtheTCBswereopenedbyavalidRPSsignal,thereactortripsignaldidnotresultinanyphysicalchangetocorereactivitybecausetheCEAswerefullyinsertedpriortothetripsignal.Therefore,thiseventhadnoimpacttothehealthandsafetyofthepublic.NRCFOAM388AI4.96)

NRCFORM366AI4-9SILICENSEEEVENTREPORT(LER)TEXTCONTINUATIONU.S.NUCLEARREGULATORYCOMMISSIOST.LUCIEUNIT105000335YEARSEQUENTIALREVISION98-001-04OF4TEXT(Ifmorespeceisrequired,useeddilionelcopiesofftVRCRearm366AjI17)2.ProcedurechangestoNOP1-0030121andNOP2-0030121,"ReactorPlantHeatup-ColdtoHotStandby,"wereinitiatedtoensurethatafterthefourthRCPisstarted,theZPMBbypasskeysremaininbypassuntilpressureisgreaterthan1900psiaandnotripsarepresent.iTheoperatorwascounseled,andtheoperatorconductedbriefingsforeachoperatingcrewtodescribetheeventindetail,includingtheseriousnessoftheevent,theuseofselfchecking,andtheneedforinvolvementfromtheoperatingcrewwhenalarmsarereceived.3.PlacardshavebeenplacedinthecontrolroomsthatrequireeitherofthefollowingconditionsbemetpriortoplacingtheZPMBkeysfrombypasstooff:a)thereactorTCBSopen,orb)theunitatnormaloperatingtemperatureandpressure.NoneNoneNRCFORM386AI4.95)