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NRCFORM366AI6-1998)LICENSEEEVENTREPORT(LER)TEXTCONTINUATIONU.S.NUCLEARREGULATORYCOMMISSIONR.E.GinnaNuclearPowerPlant50-244SEQUENTIALREVISIONNUMBERNUMBER1998-oo3-018OF9TEXTllfmorespaceisrequired,useadditionalcopiesofiVRCRearm'366AlI17)B~ACTIONTAKENORPLANNEDTOPREVENTRECURRENCE;0TherootcauseofthevalidactuationswastheunusuallyhighconcentrationofRadonandRadondecayproductsduringanatmospherictemperatureinversion,whichtrappedthenaturallyoccurringRadonintheloweratmosphere,limitingthedispersionofmatterfromthegroundintotheupper'tmosphere.Thisisanaturalphenomenon.0ThesetpointforR-37willbeadjustedtoeliminateunnecessaryconservatisminthesetpointforactuationoftheCREATS.00ThesetpointforR-36hasbeenevaluatedtodetermineifthereisunnecessaryconservatisminthesetpoint.TheR-36setpointwillremainunchanged.ContributingfactorstotheinvalidCREATSactuations,whichwereduetospikingontheseradiationmonitors,havebeenaddressedbythefollowingactions:1.ThegroundedR-37detectorandthedamagedR-37detectorcablehavebeenreplaced.2.Thedamagedinsulationonthepowersupplycablehasbeenreplaced.VI.ADDITIONALINFORMATION:A.FAILEDCOMPONENTS:ThefailedcomponentsincludedtheR-37particulatedetector(failedduetobeinggrounded)andthedetectorcable(failedduetocold-working).ThesecomponentsweremanufacturedbyorsuppliedbyNuclearResearchCorporation.ThedetectorisModelNo.MD-34DT.B.PREVIOUSLERsONSIMILAREVENTS:AsimilarLEReventhistoricalsearchwasconductedwiththefollowingresults:NodocumentationofsimilarLEReventswiththesamerootcauseatGinnaStationcouldbeidentified.NRCFORM366AI6-1998I  
NRCFORM366AI6-1998)LICENSEEEVENTREPORT(LER)TEXTCONTINUATIONU.S.NUCLEARREGULATORYCOMMISSIONR.E.GinnaNuclearPowerPlant50-244SEQUENTIALREVISIONNUMBERNUMBER1998-oo3-018OF9TEXTllfmorespaceisrequired,useadditionalcopiesofiVRCRearm'366AlI17)B~ACTIONTAKENORPLANNEDTOPREVENTRECURRENCE;0TherootcauseofthevalidactuationswastheunusuallyhighconcentrationofRadonandRadondecayproductsduringanatmospherictemperatureinversion,whichtrappedthenaturallyoccurringRadonintheloweratmosphere,limitingthedispersionofmatterfromthegroundintotheupper'tmosphere.Thisisanaturalphenomenon.0ThesetpointforR-37willbeadjustedtoeliminateunnecessaryconservatisminthesetpointforactuationoftheCREATS.00ThesetpointforR-36hasbeenevaluatedtodetermineifthereisunnecessaryconservatisminthesetpoint.TheR-36setpointwillremainunchanged.ContributingfactorstotheinvalidCREATSactuations,whichwereduetospikingontheseradiationmonitors,havebeenaddressedbythefollowingactions:1.ThegroundedR-37detectorandthedamagedR-37detectorcablehavebeenreplaced.2.Thedamagedinsulationonthepowersupplycablehasbeenreplaced.VI.ADDITIONALINFORMATION:A.FAILEDCOMPONENTS:ThefailedcomponentsincludedtheR-37particulatedetector(failedduetobeinggrounded)andthedetectorcable(failedduetocold-working).ThesecomponentsweremanufacturedbyorsuppliedbyNuclearResearchCorporation.ThedetectorisModelNo.MD-34DT.B.PREVIOUSLERsONSIMILAREVENTS:AsimilarLEReventhistoricalsearchwasconductedwiththefollowingresults:NodocumentationofsimilarLEReventswiththesamerootcauseatGinnaStationcouldbeidentified.NRCFORM366AI6-1998I  


NRCFORM366AI6-1999)LICENSEEEVENTREPORT(LER)TEXTCONTINUATIONU.S.NUCLEARREGULATORYCOMMISSIONR.E.GinnaNuclearPowerPlant50-244SEQUENTIALREVISIONNUMBERNUMBER1998-003-019OF9TEXT(Ifmorespeceisrequired,useadditionalcopiesol'VRCForm366AlI17),C.SPECIALCOMMENTS:Until1998,GinnaStationdidnotconsidertheCREATStobeanESF.In1998,newNRCguidancewaspromulgatedinNUREG-1022,Revision1.NRCspecificallylistedtheHeating,VentilatingandAirConditioningSystemforControlRoomasanexampleofanESFsystem.Therefore,GinnaStationreportingprocedureswererevisedin1998tobeinaccordancewiththisNRCguidance.Individualsrecallthat,priorto1998,thereweresomeCREATSactuationsatGinnaStation.However,theseactuationswerenotreportableat=-thosetimes.Sincetheseearlieractuationswerenotreportable,nodocumentsexisttoconfirmanyoftheseearlieroccurrences.NRCFORM366AI6-1998)  
NRCFORM366AI6-1999)LICENSEEEVENTREPORT(LER)TEXTCONTINUATIONU.S.NUCLEARREGULATORYCOMMISSIONR.E.GinnaNuclearPowerPlant50-244SEQUENTIALREVISIONNUMBERNUMBER1998-003-019OF9TEXT(Ifmorespeceisrequired,useadditionalcopiesol'VRCForm366AlI17),C.SPECIALCOMMENTS:Until1998,GinnaStationdidnotconsidertheCREATStobeanESF.In1998,newNRCguidancewaspromulgatedinNUREG-1022,Revision1.NRCspecificallylistedtheHeating,VentilatingandAirConditioningSystemforControlRoomasanexampleofanESFsystem.Therefore,GinnaStationreportingprocedureswererevisedin1998tobeinaccordancewiththisNRCguidance.Individualsrecallthat,priorto1998,thereweresomeCREATSactuationsatGinnaStation.However,theseactuationswerenotreportableat=-thosetimes.Sincetheseearlieractuationswerenotreportable,nodocumentsexisttoconfirmanyoftheseearlieroccurrences.NRCFORM366AI6-1998)}}
 
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Revision as of 13:06, 18 May 2018

LER 98-003-01:on 980904,actuations of CR Emergency Air Treatment Systems (Creats) Occurred.Caused by Radon build-up During Temp Inversion.Creats Actuation Signal Was Reset & Normal Ventilation Was Restored to CR
ML17265A469
Person / Time
Site: Ginna Constellation icon.png
Issue date: 11/25/1998
From: ST MARTIN J
ROCHESTER GAS & ELECTRIC CORP.
To:
Shared Package
ML17265A468 List:
References
LER-98-003, LER-98-3, NUDOCS 9812070106
Download: ML17265A469 (17)


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NRCFORM366!5-1999)U.UCLEARREGULATORYCOMMISSIONLICENSEEEVENTREPORT(LER)(Seereverseforrequirednumberofdigits/charactersforeachblock)APPROBYOMBNO.31RMRBC06/30/2001EstimatedburdenperresponsetocomplywiththismandatoInformationcollectionrequest:50hrs.Reportedlessonlearnedareincorporatedintothelicensingprocessandfbacktoindustry.ForwardcommentsregardingburdeestimatetotheRocordsManagementBranch(T4)F33),USNuclearRegulatoryCommlsgon,Washlfon,Dc20550001~andtothePapenvorkReductionProect(31504104)(ÃiooofManagementandBudget,Washington,DC20503.aninformationcollectiondoesnotdisplayacurrentlyvaliOMBcontrolnumber,theNRCmaynotconductorsponsor,FACILITYNAME11)R.E.GinnaPowerPlantTITLE(I)DOCKETNUMBER(2)05000244PAGEI3)IOF9RadonBuild-upDuringTemperatureInversionResultsinActuationsofControlRoomEmergencyAirTreatmentSystemsF,ÃlfhBFRRFPORTDAF.OTHF.RFCIITFe)INVO.DMONDI09DAYYEAR041998SEOVENDALREvISIONNIIMBERNDMBER1998-003-01MONIDAY11251998PACILBYNAMEPACILIIYNAME0500005000OPERATINChtoDE(9)POWERLEVEL(10)100THISFPOTISSlJBMITTRD20.2201(b)20.2203aI20.2203(a)(2)(i)20.2203(a)(2)(v)20.2203a3i20.2203(a)(3)(ii)50.73(a)(2)(i)50.73a2ii50.73(a)(2)(iii)RS)ANTOIFFUIRFIFSO10P'U50.73(a)(S0.73a73.7120.2203a2ii20.2203(a)(2)(iii)20.2203(a)(2)(iv)NAMEJohnSt.Martin-TechnicalAssistant20.2203a450.36(c)(l)50.36(c)(2)LICENSEECONTACTFORTHISLER(12)50.73a2iv50.73(a)(2)(v)50.73(a)(2)(vii)1ELEPHONENUMBER(hetudeAreaCode)(716)771-3641OTHERspecifyiaeaieaedeicer<<iaNacFsnsaeeaCOMPLETEONELINEFOREACHCOhIPONENTFAILUREDESCRIBEDINTHISREPORT(13)cAusESYSTEhfCOMPONENTMANVPACIURERREPORTABLETOEPIXSYSIEMCOMPONENT0SUPPI,FMRNTAIRFPORTRXPI?CTFD14YESgfyes,completeEXPECTEDSUBMISSIONDATE).XNOEXPECTEDSUBMISSIONDATE(15)ABSTRACT(Limitto1400spaces,i.e.,approximately1SsinaiospacedtypcNTittenlines)(16)OnSeptember4,1998,atapproximately0740EDST,theplantwasinMode1atapproximately100%steadystatereactorpower.ControlRoomRadiationMonitorsreachedtheiralarmsetpoints,andactuatedtheControlRoomEmergencyAirTreatmentSystemtoisolatetheControlRoomatmospheretoandfromoutsidea3.r.ThesameeventoccurredonSeptember15,1998atapproximately0051EDST,andSeptember18,1998at0452EDST,and,October27,1998at0706EST.Onthesedates,anatmospherictemperatureinversionwaspresent,andanunusuallyhighconcentrationofRadonbuiltupthatwastrappedduetotheinversion.ControlRoomRadiationMonitorsalarmedduetothepresenceofthisunusuallyhighconcentrationofnaturallyoccurringradioactiveRadonandRadondecayproducts'mmediateactionwastakentodeterminethesourceofradiation.Intheseevents,"airsamplesweretakenwhichdeterminedthatthesourceofradiationwasnaturallyoccurringRadonandRadondecayproducts.Theseairsamplesconfirmedthatfissionproductactiv3.tywasnotthecause.Noimmediate'correctiveactionswererequired.ARootCauseAnalysiswasconducted.TheresultsoftheRootCauseAnalysisareoutlinedinSectionIII.C.CorrectiveactiontopreventrecurrenceisoutlinedinSectionV.B.'F812070106'i)81i24PDRADQCK050002448PDR I1 NRCFORM366AI6-1999)LICENSEEEVENT.REPORT(LER)TEXTCONTINUATIONU.S.NUCLEARREGULATORYCOMMISSIONR.E.GinnaNuclearPowerPlant50-244SEQUENTIALREVISIONNUMBER'UMBER1998-oas-012OF9TEXTflfmorespeceisrequired,useedditionelcopiesofNRCForm366AiI17)I.PRE-EVENTPLANTCONDITIONS:OnSeptember4,1998,atapproximately0740EDST,theplantwasinMode1atapproximately1009steadystatereactorpower.Unrelatedtoplantactivities,anatmospherictemperatureinversionwaspresent.Atemperatureinversionlimitsthedispersionofmatterfromthegroundintotheupperatmosphere.II.DESCRIPTIONOFEVENT:A.DATESANDAPPROXIMATETIMESOFMAJOROCCURRENCES:000September4,1998,0740EDST:Firsteventdateandtime.September4,1998,0740EDST:Discoverydateandtime.September15r1998r0051EDSTSecondeventdateandtime.September15,1998,0051EDST:Discoverydateandtime.00September18,1998,0452EDST:Thirdeventdateandtime.September18,1998,0452EDST:Discoverydateandtime.00September18,1998,1631EDST:InvalidactuationofControlRoomEmergencyAirTreatmentSystem.October20,1998,0403EDST:,InvalidactuationofControlRoomEmergencyAirTreatmentSystem.October27,1998,0706EST:Fourtheventdateandtime.0October27,1998,1050EST:Fourtheventdiscoverydateand,time.B.EVENTTheControlRoomRadiationMonitorsmonitoroutsideairinthevicinityoftheControlRoom.AhighradiationsignalononeofthesemonitorswillinitiatetheControlRoomEmergencyAirTreatmentSystem(CREATS)filtrationtrainandisolateeachairsupplypathtoandfromtheControlRoom.NRCFORM366AI6-1998)

NRCFORM366AI6-199BIOIU.S.NUCLEARREGULATORYCOMMISSIONLlCENSEEEVENTREPORT(LER)TEXTCONTINUATIONR.E.GinnaNuclearPowerPlant50-244SEQUENTIALREVISIONNUMBERNUMBER1998-oo3-013OF9TEXT/Ifmorespaceisrequired,useadditionalcopiesofNRCForm366A/I17IOnSeptember4,1998,theplantwasinMode1atapproximately1004steadystatereactorpower.Duetothetemperatureinversion,therewasanunusuallyhighconcentrationofnaturallyoccurringradioactiveRadonandRadondecayproductsintheloweratmosphere.Atapproximately0740EDST,ControlRoomRadiationMonitorsreachedtheiralarmsetpoints.TheCREATSactuatedandisolatedtheControlRoomatmospheretoandfromoutsideairuponreachingthesesetpoints.SamplesweretakentodeterminetheisotopiccontentoftheairintheControlRoom.ThesesamplesdeterminedthattherewasanunusuallyhighconcentrationofRadonandRadondecayproductsfromtheoutsideair,andindicatedthatfissionproductactivitywasnotthecauseoftheincreaseinradioactivity.OnSeptember15,1998,atapproximately0051EDST,ControlRoomRadiationMonitorsreachedtheiralarmsetpointsandtheCREATSisolatedtheControlRoomatmospheretoandfromoutsideair.Again,atemperatureinversionwaspresent,andsamplesdeterminedthattherewasanunusuallyhighconcentrationofRadonandRadondecayproductsfromtheoutsideair.OnSeptember18,1998,atapproximately0452EDST,ControlRoomRadiationMonitorsreachedtheiralarmsetpointsandtheCREATSisolatedtheControlRoomatmospheretoandfromoutsideair.Forathirdtime,atemperatureinversionwaspresent,andsamplesdeterminedthattherewasanunusuallyhighconcentrationofRadonandRadondecayproductsfromtheoutsideair.OnOctober27',1998,atapproximately0706EST,ControlRoomRadiationMonitorsreachedtheiralarmsetpoints.Priortothistime,theCREATShadbeenmanuallyisolatedfortroubleshootingoftheControlRoomRadiationMonitors.Therefore,whentheradiationalarmsoccurred,noCREATSactuationorControlRoomalarmoccurred.Laterthatmorning(atapproximately1050EST),InstrumentandControl(I&C)techniciansobservedtheradiationmonitoralarmonalocalpaneloutsidetheControlRoom,andnotifiedControlRoomoperatorsofthealarm.Anothertemperatureinversionwasdeterminedtobepresent.NRCFORM366AI6-1998)

NRCFORM366AI6.199BILICENSEEEVENTREPORT(LER)TEXTCONTINUATIONU.S.NUCLEARREGULATORYCOMMISSIONR.E.GinnaNuclearPowerPlant50-244SEQUENTIALREVISIONNUMBERNUMBER1998-oos-014OF9TEXTflfmorespaceisrequired,useadditionalcopiesofNRCForm366A/1171Inadditiontothesevalidevents,thereweretwo(2)invalidCREATSactuationsthatoccurredintherecentpast.OnSeptember18,1998,atapproximately1631EDST,aninvalidCREATSactuationoccurred.ControlRoomoperatorscheckedtheControlRoomRadiationMonitorslocally,anddiscoveredthattherewasnoalarmcondition.Therewasnotemperatureinversionpresent,andtherehadbeennosignificantincreaseinradioactivityasmonitoredbytheControlRo'omRadiationMonitors.Itwasdeterminedthatthisevent(September18at1631EDST)wasaninvalidactuation.OnOctober20,1998,atapproximately0403EDST,anotherinvalidCREATSactuationoccurred.ControlRoomoperatorsdeterminedthatoneoftheControlRoomRadiationMonitorchannelshadspikedabovethealarmsetpoint.Therewasnotemperatureinversionpresent,andtherehadbeennosignificantincreaseinradioactivityasmonitoredbytheControlRoomRadiationMonitors.Itwasdeterminedthatthisevent(October20at0403EDST)wasaninvalidactuation.C~INOPERABLESTRUCTURESrCOMPONENTSrORSYSTEMSTHATCONTRIBUTEDTOTHEEVENT:NoneD.OTHERSYSTEMSORSECONDARYFUNCTIONSAFFECTED:NoneE.METHODOFDISCOVERY:TheeventsofSeptember4,15,and18wereimmediatelyapparentduetotheactuationofCREATStoisolatetheControlRoomatmospheretoandfromoutsideair.Theevent.ofOctober27wasnotapparenttoControlRoomoperators,sincetherewasnoCREATSactuationandnoalarmintheControlRoom.ThiseventwasdiscoveredbyI&Ctechnicians.NRCFORM366AI6-1998)

NRCFORM366A(6.1998)LICENSEEEVENTREPORT(LER)TEXTCONTINUATIONU.S.NUCLEARREGULATORYCOMMISSIONR.E.GinnaNuclearPowerPlant50-244'SEQUENTIALREVISIONNUMBERNUMBER1998-oo3-015OF9TEXT/lfmorespaceisrequired,useadditionalcopiesofNRC&rm366AlI17lF.OPERATORACTION:DuringtheeventsofSeptember4,15,and18,theControlRoomoperatorsacknowledgedMainControlBoardannunciatorsassociatedwiththeradiationmonitoralarmsandactuationoftheCREATS,enteredAlarmResponseProcedureAR-E-11(ControlRoomHVACIsola'tion),andnotifiedhighersupervisionandtheNRC.TheyconfirmedthatControlRoomRadiationMonitorR-37(whichmeasuresparticulateradiation)waslockedintothealarmcondition.Independentairsampleswererequested,andwhentheresultsoftheseairsamplesconfirmedthepresenceofradioactivity(RadonandRadondecay'products),theControlRoomoperatorsdeterminedthat,validactuationsoftheCREATShadoccurred.FortheeventwhichoccurredonOctober27,nooperatorresponseoractionwaswarranted.TheShiftSupervisorsubsequentlynotifiedtheNRCper,10CFR50.72(b)(2)(ii),non-emergencyfourhournotification,atapproximately1115EDSTonSeptember4,1998.OnSeptember15,1998,theNRCwasnotifiedatapproximately0442EDST.OnSeptember18,1998,theNRCwasnotifiedatapproximately0915EDST.ThislastnotificationwasslightlybeyondthefourhourtimeframeduetodelaysinconfirmingthepresenceofRadonandRadondecayproducts.OnOctober27,1998,theNRCwasnotifiedatapproximately1439EST.G.SAFETYSYSTEMRESPONSES:IFortheeventsofSeptember4,15,and18,theCREATSactuatedtoisolatetheControlRoomatmospheretoandfromoutsideairwhentheradiationmonitorsreachedtheiralarmsetpoints.FortheeventonOctober27,theCREATSwasalreadyactuatedasaprerequisitefortroubleshootingthesystem,sonoresponseoccurred.III.CAUSEOFEVENT:A.IMMEDIATECAUSE:TheimmediatecauseoftheactuationoftheCREATSwasControlRoomRadiationMonitorsreachingtheiralarmsetpoints,resultinginisolationoftheControlRoomatmospheretoandfromoutsideair.(OnOctober27,noactuationoccurred.)NRCFORM366AI6-1998)

NRCFORM366A(6-1996)LICENSEEEVENTREPORTILERITEXTCONTINUATiON.U.S.NUCLEARREGUlATORYCOMMISSIONR.E.GinnaNuclearPowerPlant50-244SEOUENTIaLREVISIONNUMBERNUMBER1998-oo3-O16OF9TEXTIifmorespeceisrequired,useedditionelcopiesofNRCForm366AII17)B.INTERMEDIATECAUSE:Theintermediatecauseoftheradiationmonitorsreachingtheiralarmsetpointswasincreasedradioactivityoftheoutsideair,duetoanunusuallyhighconcentrationofRadonandRadondecayproducts.C.ROOTCAUSE:TherewerevalidandinvalidCREATSactuationsduringtherecentpast.Forthevalidactuations,theunderlyingcauseoftheunusuallyhighconcentrationofRadonandRadondecayproductswasanatmospherictemperatureinversion;whichtrappedthenaturallyoccurringRadonintheloweratmosphere,limitingthedispersionofmatterfromthegroundintotheupperatmosphere.SamplestakenconfirmedthattheCREATSactuationwasduetothetemperatureinversion,andnotduetofissionproductactivity.Also,thealarmsetpointsforR-36andR-37havebeenevaluatedtobeunnecessarilyconservative,whichresultedinCREATSactuations.DuetotheinvalidCREATSactuations,troubleshootingandrootcauseanalysiswereperformed.Asaresult,additionalfactorswereidentifiedthatcontributedtotheinvalidCREATSactuations.TheControlRoomRadiationMonitorisactuallythree(3)separatechannelsthatanalyzeacommonsampleofoutsideairbeingsuppliedtotheCREATS.ChannelR-36monitorsnoblegas.ChannelR-37monitorsparticulate.ChannelR-38monitorsiodine.IGCpersonnelidentifiedthatthedetectorforR-37wasgrounded.TheyalsodiscoveredadamageddetectorcableforR-37,andfounddamagedinsulationonthepowersupplycabletotheControlRoomRadiationMonitor.IV.ANALYSISOFEVENT:Theseeventsarereportableinaccordancewith10CFR50.73,,LicenseeEventReportSystem,item(a)(2)(iv),whichrequiresareportof,"anyeventorconditionthatresultedinmanualorautomaticactuationofanyEngineeredSafetyFeature(ESF)includingtheReactorProtectionSystem(RPS)".CREATSislistedinNUREG-1022asanexamplesystemofwhattheNRCstaffconsiderstobeasystem"provided.to.mitigatetheconsequencesofasignificantevent."NRCFORM366AIS-1998)

I\

NRCFORM366A(8-1998)LICENSEEEVENTREPORT(LER)TEXTCONTINUATIONU.S.NUCLEARREGULATORYCOMMISSIONR.E.GinnaNuclearPowerPlant50-244SEQUENTIALREVISIONNUMBERNUMBER1998-,,oos-017OF9TEXT/Ifmorespaceisrequired,useadditionalcopiesofNRCFarm366AiI17)Anassessmentwasperformed'onsideringboththesafetyconsequencesandimplicationsofthiseventwiththefollowingresultsandconclusions:TherewerenooperationalorsafetyconsequencesorimplicationsattributedtoCREATSactuationbecause:oTheCREATSprovidesaprotectedenvironmentfromwhichoperatorscancontroltheplantfollowinganuncontrolledreleaseofradioactivity.TherewasnouncontrolledreleaseofradioactivitywhichoccurredonSeptember4,September15,September18,andOctober27.0TheCREATSactuationwasinresponsetoincreasedradioactivityinthevicinityoftheControlRoom.However,theincreasedradioactivitywasduetonaturallyoccurringRadonandRadondecayproducts.Theincreaseinradiationdetectedwasnotduetoanyplantactivity.Specifically,itwasnotduetoanincreaseinfissionproductactivitynoranuncontrolledreleaseofradioactivity.0CREATSfunctionedasperdesign,toisolatetheControlRoominresponsetolevelsofradioactivitythatresultedinreachingthealarmsetpointsontheControlRoomRadiationMonitors.Basedontheabove,itcanbeconcludedthattheplantoperatedasdesigned,thattherewerenounreviewedsafetyquestions,andthatthepublic'shealthandsafetywasassuredatalltimes.V.CORRECTIVEACTION:A.ACTIONTAKENTORETURNAFFECTEDSYSTEMSTOPRE-EVENTNORMALSTATUS:AttheconclusionofthethreetemperatureinversionsinSeptember,andaftertheControlRoomRadiationMonitorsdecreasedbelowtheiralarmsetpoints,theCREATSactuationsignalwasreset,andnormalventilationwasrestoredtotheControlRoom.FortheeventofOctober27,noCREATSactuationoccurred,'andnoactionswerewarranted.NRCFORM366AI6-1998)

NRCFORM366AI6-1998)LICENSEEEVENTREPORT(LER)TEXTCONTINUATIONU.S.NUCLEARREGULATORYCOMMISSIONR.E.GinnaNuclearPowerPlant50-244SEQUENTIALREVISIONNUMBERNUMBER1998-oo3-018OF9TEXTllfmorespaceisrequired,useadditionalcopiesofiVRCRearm'366AlI17)B~ACTIONTAKENORPLANNEDTOPREVENTRECURRENCE;0TherootcauseofthevalidactuationswastheunusuallyhighconcentrationofRadonandRadondecayproductsduringanatmospherictemperatureinversion,whichtrappedthenaturallyoccurringRadonintheloweratmosphere,limitingthedispersionofmatterfromthegroundintotheupper'tmosphere.Thisisanaturalphenomenon.0ThesetpointforR-37willbeadjustedtoeliminateunnecessaryconservatisminthesetpointforactuationoftheCREATS.00ThesetpointforR-36hasbeenevaluatedtodetermineifthereisunnecessaryconservatisminthesetpoint.TheR-36setpointwillremainunchanged.ContributingfactorstotheinvalidCREATSactuations,whichwereduetospikingontheseradiationmonitors,havebeenaddressedbythefollowingactions:1.ThegroundedR-37detectorandthedamagedR-37detectorcablehavebeenreplaced.2.Thedamagedinsulationonthepowersupplycablehasbeenreplaced.VI.ADDITIONALINFORMATION:A.FAILEDCOMPONENTS:ThefailedcomponentsincludedtheR-37particulatedetector(failedduetobeinggrounded)andthedetectorcable(failedduetocold-working).ThesecomponentsweremanufacturedbyorsuppliedbyNuclearResearchCorporation.ThedetectorisModelNo.MD-34DT.B.PREVIOUSLERsONSIMILAREVENTS:AsimilarLEReventhistoricalsearchwasconductedwiththefollowingresults:NodocumentationofsimilarLEReventswiththesamerootcauseatGinnaStationcouldbeidentified.NRCFORM366AI6-1998I

NRCFORM366AI6-1999)LICENSEEEVENTREPORT(LER)TEXTCONTINUATIONU.S.NUCLEARREGULATORYCOMMISSIONR.E.GinnaNuclearPowerPlant50-244SEQUENTIALREVISIONNUMBERNUMBER1998-003-019OF9TEXT(Ifmorespeceisrequired,useadditionalcopiesol'VRCForm366AlI17),C.SPECIALCOMMENTS:Until1998,GinnaStationdidnotconsidertheCREATStobeanESF.In1998,newNRCguidancewaspromulgatedinNUREG-1022,Revision1.NRCspecificallylistedtheHeating,VentilatingandAirConditioningSystemforControlRoomasanexampleofanESFsystem.Therefore,GinnaStationreportingprocedureswererevisedin1998tobeinaccordancewiththisNRCguidance.Individualsrecallthat,priorto1998,thereweresomeCREATSactuationsatGinnaStation.However,theseactuationswerenotreportableat=-thosetimes.Sincetheseearlieractuationswerenotreportable,nodocumentsexisttoconfirmanyoftheseearlieroccurrences.NRCFORM366AI6-1998)