ML17264B121

LER 97-004-00:on 971024,radiation Monitor Alarm Were Noted Due to Higher than Normal Radioactive Gas Concentration Resulted in Cvi.New R-12 Alarm Setpoint Was Maintained for Duration of Refueling Outage

ML17264B121
Person / Time
Site:	Ginna
Issue date:	11/24/1997
From:	MARTIN J T ROCHESTER GAS & ELECTRIC CORP.
To:
Shared Package
ML17264B120	List: ML17264B119 ML17264B121
References
LER-97-004, LER-97-4, NUDOCS 9712030140
Download: ML17264B121 (8)

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NRCFORM366r4-95)U.S.NRREGULATORYCOMMISSIOLICENSEEEVENTREPORT(LER)(Seereverseforrequirednumberofdigits/charactersforeachblock)APPEDBYOMBNO.3150-0104EXPIRES04/30/98ESTIMATEDBURDENPERRESPONSEToCOMPLYWITHTHISMANDATORYINFORMATIONCOLLECTIONREQUEST:50.0HAS.REPORTEDLESSONSLEARNEDAREINCORPORATEDINTOTHELICENSINGPROCESSANDFEDBACKTOINDUSTRY.FORWARDCOMMENTSREGARDINGBURDENESTIMATEToTHEINFORMATIONANDRECORDSMANAGEMENTBRANCHIT.6F33),U.S.NUCLEARREGULATORYCOMMISSION,WASHINGTON,DC20555.0001,ANDToTHEPAPERWORKREDUCTIONPROJECTFAC)UTYNAME(1)TITLE<4)R.E.GinnaNuclearPowerPlantDOCKETNUMBERL2)05000244PAGEI3)1OF5RadiationMonitorAlarm,DuetoHigherthanNormalRadioactiveGasConcentration,ResultsinContainmentVentilationIsolationEVENTDATE(5)LERNUMBER(6)REPORTDATE(7)OTHERFACILITIESINVOLVED(8)MONTHDAYYEARSEQUENTIALREVISIONNUMBERNUMBERMONTHDAYYEARFACILITYHAMBDOCKETNUMBER1024OPERATINGMODE(9)POWERLEVEL(10)9797-004-002497FACIUTYNAMEDOCKETNUMBERmore)(11)20,2201(b)20.2203(a)(1)20.2203(aH2)(i)20.2203(a)(2)(ii)20.2203(B)(2)(iii)20.2203(a)(2)(iv)20.2203(a)(2)(v)20.2203(a)(3)(i)20.2203(aH3)(ii)20.2203(a)(4)50.36(c)(1)50.36(cH2)50./3(a)(2Hi)50.73(aH2Hii)50.73(a)(2)(iii)50.73(aH2Hiv)50.73(aH2Hv)50.73(a)(2)(vii)50.73(a)(2)(viii)50.73(a)(2)(x)73.71OTHERSpecifyinAbstractbe)oworinNRCForm366ATHISREPORTISSUBMITTEDPURSUANTTOTHEREQUIREMENTSOF10CFR5:(CheckoneorNAMELICENSEECONTACTFORTHISLER(12)TELEPHONENUMBER(IndvdeAreaCode)JohnT.St.Martin-TechnicalAssistant(716)771-3641CAUSESYSTEMCOMPONENTMANUFACTURERREPO))TABLEToNP)IDSCAUSESYSTEMCOMPONENTMANUFACTUREACOMPLETEONELINEFOREACHCOMPONENTFAILUREDESCRIBEDINTHISREPORT(13)REPOIITABLETONPRDSSUPPLEMENTALREPORTEXPECTEDl14)YES(lfyes,completeEXPECTEDSUBMISSIONDATE).XNOEXPECTEDSUBMISSIONDATE(15)MONTHDAYYEARABSTRACT(Limitto1400spaces,i.e.,approximately15single.spacedtypewrittenlines)(16)OnOctober24,1997,atapproximately1919EST,theplantwasinMode6withthereactorcoolantsystembeingmaintainedatatemperatureof110degreesFanddepressurizedandvented.Theplantwasshutdownforrefueling.Duringactivitiesassociatedwithopeningtheprimarysidesofthesteamgenerators,radioactivegasconcentrationincreasedwithinthecontainment.AcontainmentventilationisolationoccurredwhencontainmentgasradiationmonitorR-12reacheditshighalarmsetpoint.immediateoperatoractionwastoperformtheapplicableactionsofalarmresponseprocedures.CorrectiveactiontopreventrecurrenceisoutlinedinSectionV.B.NRCFORM366(4-95)97i2030i4097ii24PDRADOCK050002448PDR NRCFORM366A(4-95)LICENSEEEVENTREPORT(LER)TEXTCONTINUATION.NUCLEARREGULATORYCOMMISSIONFACILITYNAME(1)R.E.GinnaNuclearPowerPlantDOCKET05000244LERNUMBER(6)YEARSEQUENTIALREVISIONNUMBERNUMBER97-004-00PAGE(3)2OF5TEXT/Ifmorespeceisrequired,useeddidonalcopiesofNRCForm386A/(17)PRE-EVENTPLANTCONDITIONS:OnOctober24,1997,theplantwasinMode6withthereactorcoolantsystem(RCS)beingmaintainedatatemperatureofapproximately110degreesFanddepressurizedandvented.Theplantwasshutdownforrefueling.Acontainment(CNMT)purgewasoccurring,andotheractivitieswereinprogressinpreparationforopeningtheprimarysidesofthesteamgenerators(SG).Atapproximately1900EST,allunnecessarypersonnelhadbeenremovedfromtheCNMT,inanticipationofremovingtheSGprimarymanwaydiaphragms.Whenthediaphragmswereremoved,radionoblegasconcentrationincreasedinCNMT.DESCRIPTIONOFEVENT:A.DATESANDAPPROXIMATETIMESOFMAJOROCCURRENCES:October24,1997,1919EST:Eventdateandtime.October24,1997,1919EST:Discoverydateandtime.October24,1997,1920EST:ControlRoomoperatorsverifyallcontainmentventilationisolationfunctionshaveoccurred.October24,1997,2125EST:Containmentventilationisolationisresetandcontainmentpurgeresumed.B.EVENT:OnOctober24,1997,radionoblegasconcentrationwasincreasinginCNMT,duetoremovingtheSGprimarymanwaydiaphragms.Atapproximately1919EST,CNMTgasradiationmonitorR-12(partoftheCNMTradiationmonitoringsystem,orRMS)reacheditshighalarmsetpoint.WhenR-12alarms,itresultsinaCNMTventilationisolation(CVI)signal.WhentheCVIoccurred,thefollowingMainControlBoardannunciatorswerereceived:A-25(ContainmentVentilationIsolation)andE-16(RMSProcessMonitorHighActivity).TheControlRoomoperators,respondingtotheaboveannunciators,observedthatR-12wasonalarm.TheControlRoomoperatorsimmediatelyreferredtoAlarmResponseproceduresAR-A-25andAR-RMS,andverifiedthatallCNMTventilationisolationvalves(thatwereopen)closedasdesigned,andthatCNMTpurgeandexhaustfanstripped.Theyperformedtheapplicableactionsofthealarmresponseprocedures.NRCFORM366A(4-95)

NRCFORM366A(4-95ILICENSEEEVENTREPORT(LER)TEXTCONTINUATION.NUCLEARREGULATORYCOMMISSIONFACILITYNAME(1)"R.E.GinnaNuclearPowerPlantDOCKET05000244LERNUMBER(6IYEARSEQUENTIALREVISIONNUMBERNUMBER97-004-00PAGE(313OF5TEXTflfmorespoceisrequired,useedditionelcopiesofNRCForm386AJ(17)AfterconsultingwiththeRadiationProtectiongroup,itwasdeterminedthatthehighalarmsetpointforR-12wassetconservatively(approximately1%ofTechnicalSpecificationlimit).RadiationProtectionevaluatedconditionsandrecommendedincreasingthissetpoint.Atemporaryprocedurechangewasinitiatedtotemporarilyincreasethissetpoint,asrecommendedbyRadiationProtection.Afterthissetpointwastemporarilyincreased,theCVIsignalwasreset,andtheControlRoomoperatorsresumedtheCNMTpurgethathadbeeninprogress.C.INOPERABLESTRUCTURES,COMPONENTS,ORSYSTEMSTHATCONTRIBUTEDTOTHEEVENT:NoneD.OTHERSYSTEMSORSECONDARYFUNCTIONSAFFECTED:WiththeCVI,thefollowingmajorcomponentswereisolated:CNMTPurgeExhaustfanR-10A,CNMTIodineRMSMonitorR-11,CNMTParticulateRMSMonitorR-12,CNMTGasRMSMonitorE.METHODOFDISCOVERY:ThiseventwasimmediatelyapparentduetoMainControlBoardannunciatoralarmsandCVIpositionindicationontheMainControlBoard.F.OPERATORACTION:TheControlRoomoperatorsrespondedtotheeventbyperformingtheapplicableactionsofalarmresponseprocedures,andotheractionsasdeemednecessary.TheyverifiedpropervalvepositionforallCVIvalves.TheControlRoomoperatorsnotifiedhighersupervisionandtheNRCresidentinspector.TheShiftSupervisorsubsequentlynotifiedtheNRCper10CFR50.72(b)(2)(ii),non-emergencyfourhournotification,atapproximately2243ESTonOctober24,1997.G.SAFETYSYSTEMRESPONSES:TheCVIvalves(thatwereopen)closedautomaticallyfromtheCVIsignal,asperdesign.NRCFORM366A(4.95)

NRCFORM366A(4-95)LICENSEEEVENTREPORT(LER)TEXTCONTINUATION.NUCLEARREGULATORYCOMMISSIONFACILITYNAME(1)R.E.GinnaNuclearPowerPlantDOCKET05000244LERNUMBER(6)YEARSEQUENTIALREVISIONNUMBERNUMBER97-004-00PAGE(3)4OF5TEXTilfmorespaceisrequired,useadditionalcopiesofNRCForm366AJ(17)III.CAUSEOFEVENT:A.IMMEDIATECAUSE:TheimmediatecauseoftheCVIwasduetoR-12reachingitshighalarmsetpoint.B.INTERMEDIATECAUSE:TheintermediatecauseofR-12reachingitshighalarmsetpointwasincreasedradionoblegasconcentrationinCNMTafterremovingtheSGprimarymanwaydiaphragms.C.ROOTCAUSE:TheunderlyingcauseoftheincreasedradionoblegasconcentrationinCNMTwashigherthannormalRCSactivity.ThishigherthannormalRCSactivitywasduetofueldefects.IV.ANALYSISOFEVENT:Thiseventisreportableinaccordancewith10CFR50.73,LicenseeEventReportSystem,item(a)(2)(iv),whichrequiresareportof,"Anyeventorconditionthatresultedinmanualorautomaticactuationofanyengineeredsafetyfeature(ESF)".TheCVIduetoR-12alarmwasanautomaticactuationofanESFsubsystem.Anassessmentwasperformedconsideringboththesafetyconsequencesand.implicationsofthiseventwiththefollowingresultsandconclusions:TherewerenooperationalorsafetyconsequencesorimplicationsattributedtotheCVIbecause:TheCVIoccurredinMode6,whentheCVIisnotrequiredtobeoperable.AspertheGinnaStationImprovedTechnicalSpecifications(ITS),Specification3.3.5(ContainmentVentilationIsolationInstrumentation)isonlyapplicableinModes1-4,duringcorealterations,andduringmovementofirradiatedfuelassemblieswithinCNMT.ITSBasisstates:"WhileinMODES5and6withoutfuelhandlinginprogress,thecontainmentventilationisolationinstrumentationneednotbeOPERABLEsincethepotentialforradioactivereleasesisminimizedandoperatoractionissufficient,toensurepostaccidentoffsitedosesaremaintainedwithinthelimitsof10CFR100.11."NRCFORM366A(4-95)

NRCFORM366A(4-95)LICENSEEEVENTREPORT(LER)TEXTCONTINUATION.NUCLEARREGULATORYCOMMISSIONFACILITYNAME(1)R.E.GinnaNuclearPowerPlantDOCKET05000244LERNUMBER(6)YEARSEQUENTIALREVISIONNUMBERNUMBER97-004-00PAGE(3)5OF5TEXTilfmorespaceisrequired,useeddidonelcopiesofNRCForm3MAi(17)o~TheCVIsystemoperatedasdesigned.oThecomponentsaffectedwerecapableofwithstandingtheisolation.oTheCVIwasintheconservativedirection.Basedontheabove,itcanbeconcludedthatthepublic'shealthandsafetywasassuredatalltimes.V.CORRECTIVEACTION:A.ACTIONTAKENTORETURNAFFECTEDSYSTEMSTOPRE-EVENTNORMALSTATUS:TheControlRoomoperatorsresettheCVIsignalandrestoredthesystemtopre-eventstatus(withatemporarilyhigherR-12alarmsetpoint).ACTIONTAKENORPLANNEDTOPREVENTRECURRENCE'ThenewR-12alarmsetpointwasmaintainedforthedurationoftherefuelingoutage.oFuturerefuelingoutagepreparationactivitieswillspecificallyreviewthepotentialneedtoreviseRMSsetpoints,basedonRCSactivity.VI.ADDITIONALINFORMATION:A.FAILEDCOMPONENTS:NoneB.PREVIOUSLERsONSIMILAREVENTS:AsimilarLEReventhistoricalsearchwasconductedwiththefollowingresults:NodocumentationofsimilarLEReventswiththesamerootcauseatGinnaStationcouldbeidentified.C.SPECIALCOMMENTS:NoneNRCFORM366A(4-95)

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