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{{#Wiki_filter:NRCForm366U.S.NUCLEARREGULATORYCOMMISSION(6-1996)LICENSEEEVENTREPORT(LER)(Seereverseforrequirednumberofdigits/charactersforeachblock)APPROVEOBY0MBNO.3(504)104EXPIRES05/30/2001ESTPAATEDSVRDENPERRESPONSETOCOMPLYWITHTI43MANDATORYeIFORMATIONCOLLECTIONREOVEST:500HRS.REPORTEDLESSONSLEARNEDAREerCORPORATEDtrfoTHELICENSINOPROCESSANOFEDSACKTOINDVSTRYFORWARDCOIVFAENTSREOARDINOSVRDENESTSJATETOTHEeIFORMATKNIANORECORDSMANAGEMENTSRANCHIT%FaaxV.SNVCLEARREOIAATORYCOLSJISSIOH.WASHNOTON.OC20555000I,ANOTOTHEPAPERWORKREDVCTIONPROJECT(3I500IDIIOFFCEOFScrNAOEMENTANDSVOOETWASHrNOTONiDC20500FACILITYNAME(1)CookNuclearPlantUnit1DOCKETNUMBER(2)05000-315PAOE(3)1of4TITLE(4)VictoreenContainmentHighRangeRadiationMonitorsNotEnvironmentallyQualifiedtoWithstandPost-LOCAConditionsEVENTDATE(5)LERNUMBER(6)REPORTDATE(7)OTHERFACILITIESINVOLVED(8)MONTHDAY0716YEAR1999YEARSEQUENTIALNUMBER1999-019REVISIONNUMBER00MONTH08DAY16YEAR1999FACILITYNAMED.C.Cook-Unit2FACILITYNAMEDOCKETNUMBER05000-316DOCKETNUMBEROPERATINGMODE(9)THISREPORTISSUBMITTEDPURSUANTTOTHEREQUIREMENTSOF10CFRIi:(Checkoneormor20.2201(b)20.2203(a)(2)(v)50.73(a)(2)(i)e)(11)50.73(a)(2)(viii)POWERLEVEL(10)020.2203(a)(1)20.2203(a)(2)(i)20.2203(a)(2)(ii)20.2203(a)(2)(iii)20.2203(a)(2)(iv)20.2203(a)(3)(i)20.2203(a)(3)(ii)20.2203(a)(4)50.36(c)(1)50.36(c)(2)LICENSEECONTACTFORTHISLER(12)50.73(a)(2)(ii)50.73(a)(2)(iii)50.73(a)(2)(iv)50.73(a)(2)(v)50.73(a)(2)(vii)50,73(a)(2)(x)73.71OTHERSpeo/YinAbstractbetorvornNRCForm3SSANAMEMs.BrendaW.O'ourke,ComplianceEngineerTELEPHONENUMBER0ndrrdeAreaCode)(616)465-5901x2604COMPLETEONELINEFOREACHCOMPONENTFAILUREDESCRIBEDINTHISREPORT13CAUSESYSTEMCOMPONNTMAIJUFACTURRREPORTABLETOEPIXCAUSESYSTEMCOMPONENTMANUFACTURERREPORTABLETOEPIXSUPPLEMENTALREPORTEXPECTED14YESIIYescomleteEXPECTEDSUBMISSIONDATEXEXPECTEDSUBMISSIONDATE15MONTHDAYYEARAbstract(Limitto1400spaces,I.e.~approximately15single-spacedtypewrittenlines)(16)OnMay21,1999,duringanEnvironmentalQualification(EQ)programself-assessment,preliminaryreviewidentifiedthatthecontainmenthighrangeradiationmonitors(HRRM)maynotbeenvironmentallyqualifiedtowithstandtheeffectsofaLossofCoolantAccident(LOCA).Theself-assessmentfoundthatD.C.Cook'sevaluationofNRCInformationNotice(IN)97-45,"EnvironmentalQualificationDeficiencyforCablesandContainmentPenetrationPigtails,"failedtoadequatelyaddressthesusceptibilityofthecontainmentHRRMstomoistureintrusion.IN'97-45identifiedthatelectricalsignalcablesandconnectorsfoundinHRRMsaresensitivetomoistureexposureeffects,suchasfromaLOCAorpipebreakevent.IndustryeventshaveidentifiedthatmoistureintrusionintothecablejacketandconnectorshasresultedinerraticindicationofradiationlevelsandlossofHRRMfunction.BasedoncontinuedevaluationoftheEQdeficiencies,theUnit1and2HRRMsweredeclaredinoperableonJuly16,1999.Theapparentcausewasinadequatedesigncontrol.InresponsetoNRCIN89-63,adesignchangetotheHRRMsystemaddeddrainagefeaturestoseveralcomponents.However,theEQrequirementthattheHRRMsystembeleaktightagainstpossiblemoistureintrusionwasnotconsidered.ApermanentsolutionforthesusceptibilityoftheHRRMstomoistureintrusionwillbedevelopedtosupportHRRMoperabilityinModes1-4.OptionsforthepermanentsolutionarecurrentlyunderreviewandthemethodselectedwillbeimplementedpriortoMode4foreachunit.Anevaluationoftheas-builtconfigurationforotherlowsignalcurrentapplicationEQequipmentisalsobeingperformedtoidentifyotherelectricalequipmentthatmaybesusceptibletomoistureintrusionduetoaLOCAand/orpipebreakcondition.ThisevaluationwillbecompletedbySeptember30,1999.Thisconditionhasminimalsafetysignificanceduetotheavailabilityofalternatepost-accidentradiationmonitoringinstrumentation.'3)'T)082402853)'T)08'PDRADOCK050003i5SPDR  
{{#Wiki_filter:NRCForm366U.S.NUCLEARREGULATORY COMMISSION (6-1996)LICENSEEEVENTREPORT(LER)(Seereverseforrequirednumberofdigits/characters foreachblock)APPROVEOBY0MBNO.3(504)104 EXPIRES05/30/2001 ESTPAATED SVRDENPERRESPONSETOCOMPLYWITHTI43MANDATORY eIFORMATION COLLECTION REOVEST:500HRS.REPORTEDLESSONSLEARNEDAREerCORPORATED trfoTHELICENSINO PROCESSANOFEDSACKTOINDVSTRYFORWARDCOIVFAENTS REOARDINO SVRDENESTSJATETOTHEeIFORMATKNI ANORECORDSMANAGEMENT SRANCHIT%FaaxV.SNVCLEARREOIAATORY COLSJISSIOH.
WASHNOTON.
OC20555000I, ANOTOTHEPAPERWORK REDVCTION PROJECT(3I500IDII OFFCEOFScrNAOEMENT ANDSVOOETWASHrNOTONi DC20500FACILITYNAME(1)CookNuclearPlantUnit1DOCKETNUMBER(2) 05000-315 PAOE(3)1of4TITLE(4)Victoreen Containment HighRangeRadiation MonitorsNotEnvironmentally Qualified toWithstand Post-LOCA Conditions EVENTDATE(5)LERNUMBER(6)REPORTDATE(7)OTHERFACILITIES INVOLVED(8)MONTHDAY0716YEAR1999YEARSEQUENTIAL NUMBER1999-019REVISIONNUMBER00MONTH08DAY16YEAR1999FACILITYNAMED.C.Cook-Unit2FACILITYNAMEDOCKETNUMBER05000-316 DOCKETNUMBEROPERATING MODE(9)THISREPORTISSUBMITTED PURSUANTTOTHEREQUIREMENTS OF10CFRIi:(Checkoneormor20.2201(b)20.2203(a)(2)(v) 50.73(a)(2)(i) e)(11)50.73(a)(2)(viii)
POWERLEVEL(10)020.2203(a)(1) 20.2203(a)(2)(i) 20.2203(a)(2)(ii) 20.2203(a)(2)(iii) 20.2203(a)(2)(iv) 20.2203(a)(3)(i) 20.2203(a)(3)(ii) 20.2203(a)(4) 50.36(c)(1) 50.36(c)(2)
LICENSEECONTACTFORTHISLER(12)50.73(a)(2)(ii) 50.73(a)(2)(iii) 50.73(a)(2)(iv) 50.73(a)(2)(v) 50.73(a)(2)(vii) 50,73(a)(2)(x) 73.71OTHERSpeo/YinAbstractbetorvornNRCForm3SSA NAMEMs.BrendaW.O'ourke,Compliance EngineerTELEPHONE NUMBER0ndrrdeAreaCode)(616)465-5901x2604COMPLETEONELINEFOREACHCOMPONENT FAILUREDESCRIBED INTHISREPORT13CAUSESYSTEMCOMPONNTMAIJUFACTUR RREPORTABLE TOEPIXCAUSESYSTEMCOMPONENT MANUFACTURER REPORTABLE TOEPIXSUPPLEMENTAL REPORTEXPECTED14YESIIYescomleteEXPECTEDSUBMISSION DATEXEXPECTEDSUBMISSION DATE15MONTHDAYYEARAbstract(Limitto1400spaces,I.e.~approximately 15single-spaced typewritten lines)(16)OnMay21,1999,duringanEnvironmental Qualification (EQ)programself-assessment, preliminary reviewidentified thatthecontainment highrangeradiation monitors(HRRM)maynotbeenvironmentally qualified towithstand theeffectsofaLossofCoolantAccident(LOCA).Theself-assessment foundthatD.C.Cook'sevaluation ofNRCInformation Notice(IN)97-45,"Environmental Qualification Deficiency forCablesandContainment Penetration Pigtails,"
failedtoadequately addressthesusceptibility ofthecontainment HRRMstomoistureintrusion.
IN'97-45identified thatelectrical signalcablesandconnectors foundinHRRMsaresensitive tomoistureexposureeffects,suchasfromaLOCAorpipebreakevent.Industryeventshaveidentified thatmoistureintrusion intothecablejacketandconnectors hasresultedinerraticindication ofradiation levelsandlossofHRRMfunction.
Basedoncontinued evaluation oftheEQdeficiencies, theUnit1and2HRRMsweredeclaredinoperable onJuly16,1999.Theapparentcausewasinadequate designcontrol.InresponsetoNRCIN89-63,adesignchangetotheHRRMsystemaddeddrainagefeaturestoseveralcomponents.
However,theEQrequirement thattheHRRMsystembeleaktight againstpossiblemoistureintrusion wasnotconsidered.
Apermanent solutionforthesusceptibility oftheHRRMstomoistureintrusion willbedeveloped tosupportHRRMoperability inModes1-4.Optionsforthepermanent solutionarecurrently underreviewandthemethodselectedwillbeimplemented priortoMode4foreachunit.Anevaluation oftheas-builtconfiguration forotherlowsignalcurrentapplication EQequipment isalsobeingperformed toidentifyotherelectrical equipment thatmaybesusceptible tomoistureintrusion duetoaLOCAand/orpipebreakcondition.
Thisevaluation willbecompleted bySeptember 30,1999.Thiscondition hasminimalsafetysignificance duetotheavailability ofalternate post-accident radiation monitoring instrumentation.
'3)'T)08240285 3)'T)08'PDRADOCK050003i5SPDR  


NRCFORM366AU.s.NUCLEARREGULATORYCOMMISSION(6-1998)LICENSEEEVENTREPORT(LER)TEXTCONTINUATIONFACILITYNAME(1)CookNuclearPlantUnit1DOCKETNUMBER(2)05000-315YEARLERNUMBER(6)SEQUENTIALNUMBERREVISIONNUMBERPAGE(3)2of4TEXT(lfmorespaceisrequired,useadCh'tionalcopiesofNRCForm(366A)(17)ConditionsPriortoEventUnit1wasinMode5,ColdShutdownUnit2wasinMode5,ColdShutdown1999-01900DescritionofEventOnMay21,1999,duringanEnvironmentalQualification(EQ)programself-assessment,preliminaryreviewidentifiedthattheRadiationMonitoringSystem's(RMS)[EIIS:IL]Victoreencontainmenthighrangeradiationmonitors(HRRM)maynotbeenvironmentallyqualifiedtowithstandtheeffectsofaLossofCoolantAccident(LOCA).Theself-assessmentfoundthatD.C.Cook'sevaluationofNRCInformationNotice(IN)97-45,"EnvironmentalQualificationDeficiencyforCablesandContainmentPenetrationPigtails,"failedtoadequatelyaddressthesusceptibilityofthecontainmentHRRMstomoistureintrusion.IN97-45identifiedthatelectricalsignalcables[EIIS:CBL1]andconnectors[EIIS:CON]foundinHRRMsaresensitivetomoistureexposureeffects,suchasfromaLOCAorpipebreakevent.Industryeventshaveidentifiedthatmoistureintrusionintothecablejacketandconnectorscanresultinerraticindicationofradiationlevelsincontainment.Inaddition,Supplement1toIN97-45identifiedthatHRRMshaveexperiencedsignificantpositiveandnegativecurrentflowasaresultofinducedcurrentsinRockbestoscoaxialsignalcableswhenexposedtohightemperaturetransientconditions.Asaresult,thedetectionfunctionoftheHRRMswouldbeimpacted.RecentevaluationoftheHRRMEQdeficienciesidentifiedthatinresponsetoNRCIN89-63,"PossibleSubmergenceofElectricalCircuitsLocatedAbovetheFloodLevelBecauseofWaterIntrusionandLackofDrainage,"D.C.Cookaddeddrainagefeatures(e.g.,weepholesandslitsinsealtiteflexconduit)totheHRRMelectricalenclosures(conduitandjunctionboxes[EIIS:JBX])incontainment.However,thisresultedinanon-leaktightHRRMconfiguration,potentiallyexposingthemoisturesensitivecomponentstoLOCAconditions.Basedonaboveinformation,itwasconcludedthattheUnit1and2HRRMswouldnotbecapableofperformingtheirintendeddesignfunction.Asaresult,onJuly16,1999,theHRRMsweredeclaredinoperableat1558hours.CauseofEventTheapparentcausewasinadequatedesigncontrol.InresponsetoNRCIN89-63,adesignchangetotheHRRMsystemaddeddrainagefeaturestoseveralcomponents.However,theEQrequirementthattheHRRMsystembeleaktightagainstpossiblemoistureintrusionwasnotconsidered.SubsequentopportunitiestoidentifythisconditionweremissedduringD.C.Cook'sevaluationofIN97-45anditssupplement.TheconcernsidentifiedintheInformationNoticeweredeterminednottobeapplicabletoD.C.CookbecausetheHRRMsuseBrandRexsignalcablingversusRockbestoscablingasdescribedinIN97-45.AnalsisofEventThisLERisbeingsubmittedinaccordancewiththerequirementsof10CFR50.73(a)(2)(i)(B)foraconditionprohibitedbyplantTechnicalSpecifications.TS3.3.3.1requiresthecontainmentHRRMstobeoperableinModes1-4.UFSARSection11.3,statesthattheRadiationMonitoringSystemisdesignedtoperformtwobasicfunctions:1)warnofanyradiationhazardswhichmightdevelop,and2)giveearlywarningwhichmightleadtoaradiationhazardorplantdamage.TheRMSinstrumentsarelocatedatselectedpointsinandaroundtheplanttodetect,compute,andrecordradiationlevels.ThecomponentsoftheRMSaredesignedtooperateduringallexpectedenvironmentalconditionsfornormaloperation,andspecificcomponentsaredesignedtooperateduringadverseoraccidentconditions.ThesubjectradiationmonitorsincludetheVictoreencontainmenthighrangeradiationmonitors(1-VRA-1310/1410and2-VRA-2310/2410)whichprovideindicationofcontainmentradiationlevelsduringpost-LOCAconditionsandareutilizedinassessingpossiblecoredamage.NRCFORM366A(6-1998)
NRCFORM366AU.s.NUCLEARREGULATORY COMMISSION (6-1998)LICENSEEEVENTREPORT(LER)TEXTCONTINUATION FACILITYNAME(1)CookNuclearPlantUnit1DOCKETNUMBER(2) 05000-315 YEARLERNUMBER(6)SEQUENTIAL NUMBERREVISIONNUMBERPAGE(3)2of4TEXT(lfmorespaceisrequired, useadCh'tional copiesofNRCForm(366A)(17)Conditions PriortoEventUnit1wasinMode5,ColdShutdownUnit2wasinMode5,ColdShutdown1999-01900DescritionofEventOnMay21,1999,duringanEnvironmental Qualification (EQ)programself-assessment, preliminary reviewidentified thattheRadiation Monitoring System's(RMS)[EIIS:IL]
NRCFORM366AU.s.NUCLEARREGULATORYCOMMISSION(6-1998)LICENSEEEVENTREPORT(LER)TEXTCONTINUATIONFACILITYNAME(1)CookNuclearPlantUnit1OOCKETNUMBER(2)05000-315YEAR1999LERNUMBER(6)SEQUENTIALNUMBER019REVISIONNUMBER00PAGE(3)3of4TEXT(ifmorespaceisrequired,useaddi(tonalcopiesofNRCForm(366A)(17)AtypicalHRRMconsistsofadetector,associatedBrandRextriaxialcabling,conduit,junctionboxesandAmphenolconnectors.Amphenolconnectorsarelocatedatthepenetrationpigtailsandotherelectricalcableconnections,andatajunctionboxlocatedatthetopofthecontainmentpenetrationflood-uptubes.EachAmphenolconnectorisenclosedinaRaychembootseal,withtheassociateddetectorcablingcontainedwithinaconduitsystem.ThejunctionboxandconduitsystemcontainweepholeswhichwereaddedinresponsetoNRCIN89-63.EQtestingperformedbyVictoreenin1978experiencednumerousfailuresinattemptingtoqualifyaconnectorassemblyforin-containmentLOCAuse.TheonlydocumentedsuccessfulsimulatedLOCAtestingwasforcableandconnectorsthatwereenclosedinleaktightconduits.Thisconfigurationpreventsmoistureintrusionintothecableandconnectorsduringpost-LOCAconditions.NRCIN97-45,identifiedpotentialEQdeficienciesassociatedwithRockbestoscoaxialcablesandAmphenolconnectorsusedincontainmentHRRMsystems.SubsequentvendorEQtestingconcludedthatmoisturecouldpermeatetheHRRMcoaxialcablejacketduringpLOCAandcausepartialshortingofthemonitorsignalattheconnectors.BecauseofthesmallsignalcurrentoutputfromtheHRRMs(nominallypico-amperes),partialshortingofthesignalcouldresultinlossofHRRMfunction.Inaddition,Supplement1identifiedthatHRRMscablingissusceptibletothermally-inducedcurrentsasaresultofextremetemperaturetransients.Thermally-inducedcurrentshavebeenfoundtoimpacttheaccuracyoftheHRRMs.EIn1990,drainagefeatureswereaddedtoD.C.Cook'sHRRMsysteminresponsetoNRCIN89-63.IndustryconcernswereidentifiedregardingthelackofdrainageholesincontainmentelectricalenclosuresthatmaybecomesubmergedduringaLOCAevent.Withouttheappropriatedrainage,watercouldcollectinsidetheenclosuresandcauseshortingoftheelectricalcomponentscontainedintheenclosures.AlthoughD.C.Cook'sHRRMconduitsystemcontainsweepholes,themoistureintrusionpotentialofthesubjectconnectorsismuchmorelimitedthanthatdescribedintheVictoreentestreportsandNRCIN97-45.Inthesetests,thecoaxialcableandsealedconnectorsweredirectlyexposedtosteamandsprayconditions,whereasD.C.Cook'scableandsealedconnectorsarecontainedwithinaconduitsystem.Becauseoftheadditionalprotectiongivenbytheconduitsystem,themaximumamountofmoisturethatcouldpotentiallycomeincontactwiththeconnectorsislimitedbytheinternalfreeairspaceoftheconduit.DuringtheincreasingcontainmentpressureportionofaLOCAtransient,thesteamwouldfilltheconduit,displacingtheairinsidetheconduitandresultinthetrappedsteamcondensingonthecoldercableandconduitinternalwalls.Thisamountofmoistureintrusionismuchmorelimitedthanwouldoccurinanopensystem(i.e.,withnoconduitenclosure).ThedesignfunctionofthecontainmentHRRMsistoprovideoperatorswithpost-LOCAindicationofcontainmentradiationlevelswhicharealsoutilizedinassessingpossiblecoredamage.AlthoughtheidentifiedEQdeficienciescouldrendertheHRRMsinoperablefollowingaLOCA,alternativemeansofperformingthismonitoringfunctionexistthroughotherpost-accidentmonitoringinstrumentation.Thisincludesthepost-accidentmonitoringsystemandthepost-accidentgrabsamplepalletinaccordancewithplantemergencyprocedures.Basedontheaboveinformation,theidentifiedconditionhasminimalsafetysignificanceduetotheavailabilityofalternatepost-accidentradiationmonitoringinstrumentation.CorrectiveActionsApermanentsolutionforthesusceptibilityoftheHRRMstomoistureintrusionwillbedevelopedtosupportHRRMoperabilityinModes1-4.OptionsforthepermanentsolutionarecurrentlyunderreviewandwillbeimplementedpriortoMode4foreachunit.Anevaluationoftheas-builtconfigurationforotherlowsignalcurrentapplicationEQequipmentisbeingperformedtoidentifyotheradditionalelectricalequipmentthatmaybesusceptibletomoistureintrusionduetoaLOCAorpipebreakcondition.TheevaluationwillincludeareviewofthecurrentEQProgramdocumentationregardingrequirementsforNRCFORM366A(6-1998)
Victoreen containment highrangeradiation monitors(HRRM)maynotbeenvironmentally qualified towithstand theeffectsofaLossofCoolantAccident(LOCA).Theself-assessment foundthatD.C.Cook'sevaluation ofNRCInformation Notice(IN)97-45,"Environmental Qualification Deficiency forCablesandContainment Penetration Pigtails,"
NRCFORM366AU.S.NUCLEARREGULATORYCOMMISSION(6-1998)LICENSEEEVENTREPORT(LER)TEXTCONTINUATIONFACILITYNAME(1)CookNuclearPlantUnit1DOCKETNUMBER(2)05000-315YEAR1999LERNUMBER(6)SEQUENTIALNUMBER019REVISIONNUMBER00PAGE(3)4of4TEXT(lfmorespaceisrequired,useadditionalcopiesofNRCEorm(366A)(17)leaktightelectricalenclosures.ThisevaluationwillbecompletedbySeptember30,1999.Basedonresultsoftheevaluation,appropriatecorrectiveactionswillbetakentoaddressanyidentifiedEQdiscrepancies.AEP:NRC:1260GH,"EnforcementActions98-150,98-151,98-152and98-186ReplytoNoticeOfViolationOctober13,1998",datedMarch19,1999,respondedtoidentifiedprogrammaticweaknessesintheplantDesignandLicensingBasisandtheTrainingandQualificationofpersonnel.TheEngineeringLeadershipPlanestablishesaconfigurationmanagementprogramtocontrolplantdesignandanewdesigncontrolprocess,whichincludesdesignverification,designdocumentcontrol,vendortechnicaldocumentationcontrolandtestingofdesignchanges.AspartoftheRestarteffort,animprovedoperatingexperienceprogramisbeingdeveloped.Inaddition,theExpandedSystemReadinessReviewprojectteamsareevaluatingoperatingexperienceinformationtoassesswhetherapplicableindustry'issueshavebeenadequatelyaddressedforapplicabilitytoD.C.Cook.PreviousSimilarEventsNoneNRCFORM366A(6-1998)}}
failedtoadequately addressthesusceptibility ofthecontainment HRRMstomoistureintrusion.
IN97-45identified thatelectrical signalcables[EIIS:CBL1]
andconnectors
[EIIS:CON]
foundinHRRMsaresensitive tomoistureexposureeffects,suchasfromaLOCAorpipebreakevent.Industryeventshaveidentified thatmoistureintrusion intothecablejacketandconnectors canresultinerraticindication ofradiation levelsincontainment.
Inaddition, Supplement 1toIN97-45identified thatHRRMshaveexperienced significant positiveandnegativecurrentflowasaresultofinducedcurrentsinRockbestos coaxialsignalcableswhenexposedtohightemperature transient conditions.
Asaresult,thedetection functionoftheHRRMswouldbeimpacted.
Recentevaluation oftheHRRMEQdeficiencies identified thatinresponsetoNRCIN89-63,"Possible Submergence ofElectrical CircuitsLocatedAbovetheFloodLevelBecauseofWaterIntrusion andLackofDrainage,"
D.C.Cookaddeddrainagefeatures(e.g.,weepholesandslitsinsealtiteflexconduit)totheHRRMelectrical enclosures (conduitandjunctionboxes[EIIS:JBX])
incontainment.
However,thisresultedinanon-leaktight HRRMconfiguration, potentially exposingthemoisturesensitive components toLOCAconditions.
Basedonaboveinformation, itwasconcluded thattheUnit1and2HRRMswouldnotbecapableofperforming theirintendeddesignfunction.
Asaresult,onJuly16,1999,theHRRMsweredeclaredinoperable at1558hours.CauseofEventTheapparentcausewasinadequate designcontrol.InresponsetoNRCIN89-63,adesignchangetotheHRRMsystemaddeddrainagefeaturestoseveralcomponents.
However,theEQrequirement thattheHRRMsystembeleaktight againstpossiblemoistureintrusion wasnotconsidered.
Subsequent opportunities toidentifythiscondition weremissedduringD.C.Cook'sevaluation ofIN97-45anditssupplement.
Theconcernsidentified intheInformation Noticeweredetermined nottobeapplicable toD.C.CookbecausetheHRRMsuseBrandRexsignalcablingversusRockbestos cablingasdescribed inIN97-45.AnalsisofEventThisLERisbeingsubmitted inaccordance withtherequirements of10CFR50.73(a)(2)(i)(B) foracondition prohibited byplantTechnical Specifications.
TS3.3.3.1requiresthecontainment HRRMstobeoperableinModes1-4.UFSARSection11.3,statesthattheRadiation Monitoring Systemisdesignedtoperformtwobasicfunctions:
1)warnofanyradiation hazardswhichmightdevelop,and2)giveearlywarningwhichmightleadtoaradiation hazardorplantdamage.TheRMSinstruments arelocatedatselectedpointsinandaroundtheplanttodetect,compute,andrecordradiation levels.Thecomponents oftheRMSaredesignedtooperateduringallexpectedenvironmental conditions fornormaloperation, andspecificcomponents aredesignedtooperateduringadverseoraccidentconditions.
Thesubjectradiation monitorsincludetheVictoreen containment highrangeradiation monitors(1-VRA-1310/1410 and2-VRA-2310/2410) whichprovideindication ofcontainment radiation levelsduringpost-LOCA conditions andareutilizedinassessing possiblecoredamage.NRCFORM366A(6-1998)
NRCFORM366AU.s.NUCLEARREGULATORY COMMISSION (6-1998)LICENSEEEVENTREPORT(LER)TEXTCONTINUATION FACILITYNAME(1)CookNuclearPlantUnit1OOCKETNUMBER(2) 05000-315 YEAR1999LERNUMBER(6)SEQUENTIAL NUMBER019REVISIONNUMBER00PAGE(3)3of4TEXT(ifmorespaceisrequired, useaddi(tonal copiesofNRCForm(366A)(17)AtypicalHRRMconsistsofadetector, associated BrandRextriaxialcabling,conduit,junctionboxesandAmphenolconnectors.
Amphenolconnectors arelocatedatthepenetration pigtailsandotherelectrical cableconnections, andatajunctionboxlocatedatthetopofthecontainment penetration flood-uptubes.EachAmphenolconnector isenclosedinaRaychembootseal,withtheassociated detectorcablingcontained withinaconduitsystem.ThejunctionboxandconduitsystemcontainweepholeswhichwereaddedinresponsetoNRCIN89-63.EQtestingperformed byVictoreen in1978experienced numerousfailuresinattempting toqualifyaconnector assemblyforin-containment LOCAuse.Theonlydocumented successful simulated LOCAtestingwasforcableandconnectors thatwereenclosedinleaktight conduits.
Thisconfiguration preventsmoistureintrusion intothecableandconnectors duringpost-LOCA conditions.
NRCIN97-45,identified potential EQdeficiencies associated withRockbestos coaxialcablesandAmphenolconnectors usedincontainment HRRMsystems.Subsequent vendorEQtestingconcluded thatmoisturecouldpermeatetheHRRMcoaxialcablejacketduringpLOCAandcausepartialshortingofthemonitorsignalattheconnectors.
BecauseofthesmallsignalcurrentoutputfromtheHRRMs(nominally pico-amperes),
partialshortingofthesignalcouldresultinlossofHRRMfunction.
Inaddition, Supplement 1identified thatHRRMscablingissusceptible tothermally-inducedcurrentsasaresultofextremetemperature transients.
Thermally-induced currentshavebeenfoundtoimpacttheaccuracyoftheHRRMs.EIn1990,drainagefeatureswereaddedtoD.C.Cook'sHRRMsysteminresponsetoNRCIN89-63.Industryconcernswereidentified regarding thelackofdrainageholesincontainment electrical enclosures thatmaybecomesubmerged duringaLOCAevent.Withouttheappropriate
: drainage, watercouldcollectinsidetheenclosures andcauseshortingoftheelectrical components contained intheenclosures.
AlthoughD.C.Cook'sHRRMconduitsystemcontainsweepholes,themoistureintrusion potential ofthesubjectconnectors ismuchmorelimitedthanthatdescribed intheVictoreen testreportsandNRCIN97-45.Inthesetests,thecoaxialcableandsealedconnectors weredirectlyexposedtosteamandsprayconditions, whereasD.C.Cook'scableandsealedconnectors arecontained withinaconduitsystem.Becauseoftheadditional protection givenbytheconduitsystem,themaximumamountofmoisturethatcouldpotentially comeincontactwiththeconnectors islimitedbytheinternalfreeairspaceoftheconduit.Duringtheincreasing containment pressureportionofaLOCAtransient, thesteamwouldfilltheconduit,displacing theairinsidetheconduitandresultinthetrappedsteamcondensing onthecoldercableandconduitinternalwalls.Thisamountofmoistureintrusion ismuchmorelimitedthanwouldoccurinanopensystem(i.e.,withnoconduitenclosure).
Thedesignfunctionofthecontainment HRRMsistoprovideoperators withpost-LOCA indication ofcontainment radiation levelswhicharealsoutilizedinassessing possiblecoredamage.Althoughtheidentified EQdeficiencies couldrendertheHRRMsinoperable following aLOCA,alternative meansofperforming thismonitoring functionexistthroughotherpost-accidentmonitoring instrumentation.
Thisincludesthepost-accident monitoring systemandthepost-accident grabsamplepalletinaccordance withplantemergency procedures.
Basedontheaboveinformation, theidentified condition hasminimalsafetysignificance duetotheavailability ofalternate post-accident radiation monitoring instrumentation.
Corrective ActionsApermanent solutionforthesusceptibility oftheHRRMstomoistureintrusion willbedeveloped tosupportHRRMoperability inModes1-4.Optionsforthepermanent solutionarecurrently underreviewandwillbeimplemented priortoMode4foreachunit.Anevaluation oftheas-builtconfiguration forotherlowsignalcurrentapplication EQequipment isbeingperformed toidentifyotheradditional electrical equipment thatmaybesusceptible tomoistureintrusion duetoaLOCAorpipebreakcondition.
Theevaluation willincludeareviewofthecurrentEQProgramdocumentation regarding requirements forNRCFORM366A(6-1998)
NRCFORM366AU.S.NUCLEARREGULATORY COMMISSION (6-1998)LICENSEEEVENTREPORT(LER)TEXTCONTINUATION FACILITYNAME(1)CookNuclearPlantUnit1DOCKETNUMBER(2) 05000-315 YEAR1999LERNUMBER(6)SEQUENTIAL NUMBER019REVISIONNUMBER00PAGE(3)4of4TEXT(lfmorespaceisrequired, useadditional copiesofNRCEorm(366A)(17)leaktight electrical enclosures.
Thisevaluation willbecompleted bySeptember 30,1999.Basedonresultsoftheevaluation, appropriate corrective actionswillbetakentoaddressanyidentified EQdiscrepancies.
AEP:NRC:1260GH, "Enforcement Actions98-150,98-151,98-152and98-186ReplytoNoticeOfViolation October13,1998",datedMarch19,1999,responded toidentified programmatic weaknesses intheplantDesignandLicensing BasisandtheTrainingandQualification ofpersonnel.
TheEngineering Leadership Planestablishes aconfiguration management programtocontrolplantdesignandanewdesigncontrolprocess,whichincludesdesignverification, designdocumentcontrol,vendortechnical documentation controlandtestingofdesignchanges.AspartoftheRestarteffort,animprovedoperating experience programisbeingdeveloped.
Inaddition, theExpandedSystemReadiness Reviewprojectteamsareevaluating operating experience information toassesswhetherapplicable industry'issues havebeenadequately addressed forapplicability toD.C.Cook.PreviousSimilarEventsNoneNRCFORM366A(6-1998)}}

Revision as of 09:11, 29 June 2018

LER 99-019-00:on 990716,noted Victoreen Containment Hrrms Not Environmentally Qualified to Withstand post-LOCA Conditions.Caused by Inadequate Design Control.Reviewing Options to Support Hrrms Operability in Modes 1-4
ML17326A091
Person / Time
Site: Cook American Electric Power icon.png
Issue date: 08/16/1999
From: OROURKE B W
AMERICAN ELECTRIC POWER CO., INC.
To:
Shared Package
ML17326A090 List:
References
LER-99-019, NUDOCS 9908240285
Download: ML17326A091 (5)


Text

NRCForm366U.S.NUCLEARREGULATORY COMMISSION (6-1996)LICENSEEEVENTREPORT(LER)(Seereverseforrequirednumberofdigits/characters foreachblock)APPROVEOBY0MBNO.3(504)104 EXPIRES05/30/2001 ESTPAATED SVRDENPERRESPONSETOCOMPLYWITHTI43MANDATORY eIFORMATION COLLECTION REOVEST:500HRS.REPORTEDLESSONSLEARNEDAREerCORPORATED trfoTHELICENSINO PROCESSANOFEDSACKTOINDVSTRYFORWARDCOIVFAENTS REOARDINO SVRDENESTSJATETOTHEeIFORMATKNI ANORECORDSMANAGEMENT SRANCHIT%FaaxV.SNVCLEARREOIAATORY COLSJISSIOH.

WASHNOTON.

OC20555000I, ANOTOTHEPAPERWORK REDVCTION PROJECT(3I500IDII OFFCEOFScrNAOEMENT ANDSVOOETWASHrNOTONi DC20500FACILITYNAME(1)CookNuclearPlantUnit1DOCKETNUMBER(2) 05000-315 PAOE(3)1of4TITLE(4)Victoreen Containment HighRangeRadiation MonitorsNotEnvironmentally Qualified toWithstand Post-LOCA Conditions EVENTDATE(5)LERNUMBER(6)REPORTDATE(7)OTHERFACILITIES INVOLVED(8)MONTHDAY0716YEAR1999YEARSEQUENTIAL NUMBER1999-019REVISIONNUMBER00MONTH08DAY16YEAR1999FACILITYNAMED.C.Cook-Unit2FACILITYNAMEDOCKETNUMBER05000-316 DOCKETNUMBEROPERATING MODE(9)THISREPORTISSUBMITTED PURSUANTTOTHEREQUIREMENTS OF10CFRIi:(Checkoneormor20.2201(b)20.2203(a)(2)(v) 50.73(a)(2)(i) e)(11)50.73(a)(2)(viii)

POWERLEVEL(10)020.2203(a)(1) 20.2203(a)(2)(i) 20.2203(a)(2)(ii) 20.2203(a)(2)(iii) 20.2203(a)(2)(iv) 20.2203(a)(3)(i) 20.2203(a)(3)(ii) 20.2203(a)(4) 50.36(c)(1) 50.36(c)(2)

LICENSEECONTACTFORTHISLER(12)50.73(a)(2)(ii) 50.73(a)(2)(iii) 50.73(a)(2)(iv) 50.73(a)(2)(v) 50.73(a)(2)(vii) 50,73(a)(2)(x) 73.71OTHERSpeo/YinAbstractbetorvornNRCForm3SSA NAMEMs.BrendaW.O'ourke,Compliance EngineerTELEPHONE NUMBER0ndrrdeAreaCode)(616)465-5901x2604COMPLETEONELINEFOREACHCOMPONENT FAILUREDESCRIBED INTHISREPORT13CAUSESYSTEMCOMPONNTMAIJUFACTUR RREPORTABLE TOEPIXCAUSESYSTEMCOMPONENT MANUFACTURER REPORTABLE TOEPIXSUPPLEMENTAL REPORTEXPECTED14YESIIYescomleteEXPECTEDSUBMISSION DATEXEXPECTEDSUBMISSION DATE15MONTHDAYYEARAbstract(Limitto1400spaces,I.e.~approximately 15single-spaced typewritten lines)(16)OnMay21,1999,duringanEnvironmental Qualification (EQ)programself-assessment, preliminary reviewidentified thatthecontainment highrangeradiation monitors(HRRM)maynotbeenvironmentally qualified towithstand theeffectsofaLossofCoolantAccident(LOCA).Theself-assessment foundthatD.C.Cook'sevaluation ofNRCInformation Notice(IN)97-45,"Environmental Qualification Deficiency forCablesandContainment Penetration Pigtails,"

failedtoadequately addressthesusceptibility ofthecontainment HRRMstomoistureintrusion.

IN'97-45identified thatelectrical signalcablesandconnectors foundinHRRMsaresensitive tomoistureexposureeffects,suchasfromaLOCAorpipebreakevent.Industryeventshaveidentified thatmoistureintrusion intothecablejacketandconnectors hasresultedinerraticindication ofradiation levelsandlossofHRRMfunction.

Basedoncontinued evaluation oftheEQdeficiencies, theUnit1and2HRRMsweredeclaredinoperable onJuly16,1999.Theapparentcausewasinadequate designcontrol.InresponsetoNRCIN89-63,adesignchangetotheHRRMsystemaddeddrainagefeaturestoseveralcomponents.

However,theEQrequirement thattheHRRMsystembeleaktight againstpossiblemoistureintrusion wasnotconsidered.

Apermanent solutionforthesusceptibility oftheHRRMstomoistureintrusion willbedeveloped tosupportHRRMoperability inModes1-4.Optionsforthepermanent solutionarecurrently underreviewandthemethodselectedwillbeimplemented priortoMode4foreachunit.Anevaluation oftheas-builtconfiguration forotherlowsignalcurrentapplication EQequipment isalsobeingperformed toidentifyotherelectrical equipment thatmaybesusceptible tomoistureintrusion duetoaLOCAand/orpipebreakcondition.

Thisevaluation willbecompleted bySeptember 30,1999.Thiscondition hasminimalsafetysignificance duetotheavailability ofalternate post-accident radiation monitoring instrumentation.

'3)'T)08240285 3)'T)08'PDRADOCK050003i5SPDR

NRCFORM366AU.s.NUCLEARREGULATORY COMMISSION (6-1998)LICENSEEEVENTREPORT(LER)TEXTCONTINUATION FACILITYNAME(1)CookNuclearPlantUnit1DOCKETNUMBER(2) 05000-315 YEARLERNUMBER(6)SEQUENTIAL NUMBERREVISIONNUMBERPAGE(3)2of4TEXT(lfmorespaceisrequired, useadCh'tional copiesofNRCForm(366A)(17)Conditions PriortoEventUnit1wasinMode5,ColdShutdownUnit2wasinMode5,ColdShutdown1999-01900DescritionofEventOnMay21,1999,duringanEnvironmental Qualification (EQ)programself-assessment, preliminary reviewidentified thattheRadiation Monitoring System's(RMS)[EIIS:IL]

Victoreen containment highrangeradiation monitors(HRRM)maynotbeenvironmentally qualified towithstand theeffectsofaLossofCoolantAccident(LOCA).Theself-assessment foundthatD.C.Cook'sevaluation ofNRCInformation Notice(IN)97-45,"Environmental Qualification Deficiency forCablesandContainment Penetration Pigtails,"

failedtoadequately addressthesusceptibility ofthecontainment HRRMstomoistureintrusion.

IN97-45identified thatelectrical signalcables[EIIS:CBL1]

andconnectors

[EIIS:CON]

foundinHRRMsaresensitive tomoistureexposureeffects,suchasfromaLOCAorpipebreakevent.Industryeventshaveidentified thatmoistureintrusion intothecablejacketandconnectors canresultinerraticindication ofradiation levelsincontainment.

Inaddition, Supplement 1toIN97-45identified thatHRRMshaveexperienced significant positiveandnegativecurrentflowasaresultofinducedcurrentsinRockbestos coaxialsignalcableswhenexposedtohightemperature transient conditions.

Asaresult,thedetection functionoftheHRRMswouldbeimpacted.

Recentevaluation oftheHRRMEQdeficiencies identified thatinresponsetoNRCIN89-63,"Possible Submergence ofElectrical CircuitsLocatedAbovetheFloodLevelBecauseofWaterIntrusion andLackofDrainage,"

D.C.Cookaddeddrainagefeatures(e.g.,weepholesandslitsinsealtiteflexconduit)totheHRRMelectrical enclosures (conduitandjunctionboxes[EIIS:JBX])

incontainment.

However,thisresultedinanon-leaktight HRRMconfiguration, potentially exposingthemoisturesensitive components toLOCAconditions.

Basedonaboveinformation, itwasconcluded thattheUnit1and2HRRMswouldnotbecapableofperforming theirintendeddesignfunction.

Asaresult,onJuly16,1999,theHRRMsweredeclaredinoperable at1558hours.CauseofEventTheapparentcausewasinadequate designcontrol.InresponsetoNRCIN89-63,adesignchangetotheHRRMsystemaddeddrainagefeaturestoseveralcomponents.

However,theEQrequirement thattheHRRMsystembeleaktight againstpossiblemoistureintrusion wasnotconsidered.

Subsequent opportunities toidentifythiscondition weremissedduringD.C.Cook'sevaluation ofIN97-45anditssupplement.

Theconcernsidentified intheInformation Noticeweredetermined nottobeapplicable toD.C.CookbecausetheHRRMsuseBrandRexsignalcablingversusRockbestos cablingasdescribed inIN97-45.AnalsisofEventThisLERisbeingsubmitted inaccordance withtherequirements of10CFR50.73(a)(2)(i)(B) foracondition prohibited byplantTechnical Specifications.

TS3.3.3.1requiresthecontainment HRRMstobeoperableinModes1-4.UFSARSection11.3,statesthattheRadiation Monitoring Systemisdesignedtoperformtwobasicfunctions:

1)warnofanyradiation hazardswhichmightdevelop,and2)giveearlywarningwhichmightleadtoaradiation hazardorplantdamage.TheRMSinstruments arelocatedatselectedpointsinandaroundtheplanttodetect,compute,andrecordradiation levels.Thecomponents oftheRMSaredesignedtooperateduringallexpectedenvironmental conditions fornormaloperation, andspecificcomponents aredesignedtooperateduringadverseoraccidentconditions.

Thesubjectradiation monitorsincludetheVictoreen containment highrangeradiation monitors(1-VRA-1310/1410 and2-VRA-2310/2410) whichprovideindication ofcontainment radiation levelsduringpost-LOCA conditions andareutilizedinassessing possiblecoredamage.NRCFORM366A(6-1998)

NRCFORM366AU.s.NUCLEARREGULATORY COMMISSION (6-1998)LICENSEEEVENTREPORT(LER)TEXTCONTINUATION FACILITYNAME(1)CookNuclearPlantUnit1OOCKETNUMBER(2) 05000-315 YEAR1999LERNUMBER(6)SEQUENTIAL NUMBER019REVISIONNUMBER00PAGE(3)3of4TEXT(ifmorespaceisrequired, useaddi(tonal copiesofNRCForm(366A)(17)AtypicalHRRMconsistsofadetector, associated BrandRextriaxialcabling,conduit,junctionboxesandAmphenolconnectors.

Amphenolconnectors arelocatedatthepenetration pigtailsandotherelectrical cableconnections, andatajunctionboxlocatedatthetopofthecontainment penetration flood-uptubes.EachAmphenolconnector isenclosedinaRaychembootseal,withtheassociated detectorcablingcontained withinaconduitsystem.ThejunctionboxandconduitsystemcontainweepholeswhichwereaddedinresponsetoNRCIN89-63.EQtestingperformed byVictoreen in1978experienced numerousfailuresinattempting toqualifyaconnector assemblyforin-containment LOCAuse.Theonlydocumented successful simulated LOCAtestingwasforcableandconnectors thatwereenclosedinleaktight conduits.

Thisconfiguration preventsmoistureintrusion intothecableandconnectors duringpost-LOCA conditions.

NRCIN97-45,identified potential EQdeficiencies associated withRockbestos coaxialcablesandAmphenolconnectors usedincontainment HRRMsystems.Subsequent vendorEQtestingconcluded thatmoisturecouldpermeatetheHRRMcoaxialcablejacketduringpLOCAandcausepartialshortingofthemonitorsignalattheconnectors.

BecauseofthesmallsignalcurrentoutputfromtheHRRMs(nominally pico-amperes),

partialshortingofthesignalcouldresultinlossofHRRMfunction.

Inaddition, Supplement 1identified thatHRRMscablingissusceptible tothermally-inducedcurrentsasaresultofextremetemperature transients.

Thermally-induced currentshavebeenfoundtoimpacttheaccuracyoftheHRRMs.EIn1990,drainagefeatureswereaddedtoD.C.Cook'sHRRMsysteminresponsetoNRCIN89-63.Industryconcernswereidentified regarding thelackofdrainageholesincontainment electrical enclosures thatmaybecomesubmerged duringaLOCAevent.Withouttheappropriate

drainage, watercouldcollectinsidetheenclosures andcauseshortingoftheelectrical components contained intheenclosures.

AlthoughD.C.Cook'sHRRMconduitsystemcontainsweepholes,themoistureintrusion potential ofthesubjectconnectors ismuchmorelimitedthanthatdescribed intheVictoreen testreportsandNRCIN97-45.Inthesetests,thecoaxialcableandsealedconnectors weredirectlyexposedtosteamandsprayconditions, whereasD.C.Cook'scableandsealedconnectors arecontained withinaconduitsystem.Becauseoftheadditional protection givenbytheconduitsystem,themaximumamountofmoisturethatcouldpotentially comeincontactwiththeconnectors islimitedbytheinternalfreeairspaceoftheconduit.Duringtheincreasing containment pressureportionofaLOCAtransient, thesteamwouldfilltheconduit,displacing theairinsidetheconduitandresultinthetrappedsteamcondensing onthecoldercableandconduitinternalwalls.Thisamountofmoistureintrusion ismuchmorelimitedthanwouldoccurinanopensystem(i.e.,withnoconduitenclosure).

Thedesignfunctionofthecontainment HRRMsistoprovideoperators withpost-LOCA indication ofcontainment radiation levelswhicharealsoutilizedinassessing possiblecoredamage.Althoughtheidentified EQdeficiencies couldrendertheHRRMsinoperable following aLOCA,alternative meansofperforming thismonitoring functionexistthroughotherpost-accidentmonitoring instrumentation.

Thisincludesthepost-accident monitoring systemandthepost-accident grabsamplepalletinaccordance withplantemergency procedures.

Basedontheaboveinformation, theidentified condition hasminimalsafetysignificance duetotheavailability ofalternate post-accident radiation monitoring instrumentation.

Corrective ActionsApermanent solutionforthesusceptibility oftheHRRMstomoistureintrusion willbedeveloped tosupportHRRMoperability inModes1-4.Optionsforthepermanent solutionarecurrently underreviewandwillbeimplemented priortoMode4foreachunit.Anevaluation oftheas-builtconfiguration forotherlowsignalcurrentapplication EQequipment isbeingperformed toidentifyotheradditional electrical equipment thatmaybesusceptible tomoistureintrusion duetoaLOCAorpipebreakcondition.

Theevaluation willincludeareviewofthecurrentEQProgramdocumentation regarding requirements forNRCFORM366A(6-1998)

NRCFORM366AU.S.NUCLEARREGULATORY COMMISSION (6-1998)LICENSEEEVENTREPORT(LER)TEXTCONTINUATION FACILITYNAME(1)CookNuclearPlantUnit1DOCKETNUMBER(2) 05000-315 YEAR1999LERNUMBER(6)SEQUENTIAL NUMBER019REVISIONNUMBER00PAGE(3)4of4TEXT(lfmorespaceisrequired, useadditional copiesofNRCEorm(366A)(17)leaktight electrical enclosures.

Thisevaluation willbecompleted bySeptember 30,1999.Basedonresultsoftheevaluation, appropriate corrective actionswillbetakentoaddressanyidentified EQdiscrepancies.

AEP:NRC:1260GH, "Enforcement Actions98-150,98-151,98-152and98-186ReplytoNoticeOfViolation October13,1998",datedMarch19,1999,responded toidentified programmatic weaknesses intheplantDesignandLicensing BasisandtheTrainingandQualification ofpersonnel.

TheEngineering Leadership Planestablishes aconfiguration management programtocontrolplantdesignandanewdesigncontrolprocess,whichincludesdesignverification, designdocumentcontrol,vendortechnical documentation controlandtestingofdesignchanges.AspartoftheRestarteffort,animprovedoperating experience programisbeingdeveloped.

Inaddition, theExpandedSystemReadiness Reviewprojectteamsareevaluating operating experience information toassesswhetherapplicable industry'issues havebeenadequately addressed forapplicability toD.C.Cook.PreviousSimilarEventsNoneNRCFORM366A(6-1998)