ML17263A330

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LER 93-003-00:on 930328,discovered Failures of Safeguard Svc Water Sys During Planned Maint.Caused by Design & Operating Environ.Replaced Affected Valves W/Qualified Spares.W/ 930720 Ltr
ML17263A330
Person / Time
Site: Ginna Constellation icon.png
Issue date: 07/20/1993
From: BACKUS W H
ROCHESTER GAS & ELECTRIC CORP.
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML17263A329 List:
References
LER-93-003, LER-93-3, NUDOCS 9307280206
Download: ML17263A330 (18)


Text

NRCFORM366~(64)9)FACILITYNAME(11US.NUCLEARREGULATORYCOMMISSIONLICENSEEEVENTREPORT(LER)inaNuclearPowerPlantAPPROVED0MBNO.31504))04EXPIRES'/30/92ESTIMATEDBURDENPERRESPONSETOCOMPLYWTHTHISINFORMATIONCOLLECTIONREOUESTI50.0HRS.FORWARDCOMMENTSREGARDINGBURDENESTIMATETOTHERECORDSANDREPORTSMANAGEMENTBRANCH(F630).U.S.NUCLEARREGULATORYCOMMISSION,WASHINGTON.DC20555,ANOTOTHEPAPERWORKREDUCTIONPROJECT(31500104).OFFICEOFMANAGEMENTANDBUDGET,WASHINGTON,DC20503,DOCKETNUMBER(2)PAGE050002441OF09DuringPlannedMaintenance,FailuresofSafeguardServiceHaterSystemHereDiscoveredREPORTDATE(7)LERNUMBER(6)EVENTDATE15)OTHFAFACILITIESINVOLVEDIS)MONTHDAYYEARYEARIP)y'..'SEOVENTIALNUMBERNUMBERRKVI)IONMONTHOAYYEARFACILITYNAMESDOCKETNUMBER(S)05000032833003007099305000OPERATINGMODE(9)POWERLFYEL00020A02(lr)20AOS(e)(1)(II20AOS(el(1)(9)20AOS(el())(ill)20AOS(el0)(lv)20AOS(el(1)(vl20.405(c)SOM(c)(1)50.36(c)l2)50.73(el(2)(ll50.73(s)(2)(9)50.73(s1(2)IIII)LICENSEECONTACTFOATHISLER(12)50.73(el(2)(lvl50,73(el(2)(v)50.73(e)l2)ivB)60.73(~)(2)(vill)(Al50.73le)(2)(villl(B)50.73(e)l2)(elTHISREPORTISSUBMITTEDPURSUANTTOTHERLOUIREMENTSOF10CFR():IChectoneormoreoltheIollowinpl(11)73.71(lr)73.71(e)OTHERISpecilyinAhttrecttrelowendInText,iVRCForm36$AIVoluntaryReportNAMEHesleyH.BackusTechnicalAssistanttotheOperationsManagerTELEPHONENUMBERAREACODE315524-4446COMPLETEONELINEFOREACHCOMPONENTFAILUREDESCRIBEDINTHISREPOAT(13)CAUSESYSTEMCOMPONENTMANUFACTUREREPORTABLETONPRDSe'.6cCAUSESYSTEMCOMPONENTMANUFAC-TUREREPORTABLEF~+~'I~+.TONPRDSBB1ISVC84YSUPPLEMENTALREPORTEXPECTED(14)EXPECTEDSUBMISSIONDATE(15)MONTHOAYYEARYESIIIym.COmpleteEXPECTEDSU84IISSIOIIDATEINOABSTRACTI(,lmlrto1400rpecet,Ie.,epproxlmetelyfilteenrlnple-specsrypewrittenliner)116)OnMarch28,1993atapproximately1200EST,withthereactorinthedefueledcondition,theMaintenanceDepartment,duringvalveimprovementprogrammaintenance,dis'coveredthattwomanuallyoperatedServiceWaterSystemValves,thatwererequiredtobeopenduringnormaloperation,werefailedintheclosedposition,andsomeisolationvalveshadexcessiveseatleakage.NoimmediateoperatoractionwasnecessarybecausethefailureswereidentifiedonoutofservicesectionsoftheServiceWaterSystem.Thecauseoftheseeventswasdeterminedtobepartlydueto'esignandpartlyduetotheoperatingenvironment.(ThiseventisNUREG-1022(B)and(X)causecodes).Correctiveactiontakenwastoreplacetheaffectedvalveswithqualifiedspares.Correctiveactionstopreventrecurrencearediscussedinsection(V)(B)ofthisreport.NRCForm366(669)9307280206930720"I(APDRADQCN05000244SPDR

NRCFOAM366A(SJ)9)US.NUCLEARREGULATOAYCOMMISSIONLICENSEEETREPORT(LER)TEXTCONTINUATIONAPPROVEDOMSNO.31500(0(5XPIAES:4/30/92IMATEOSURDENPERRESPONSETOCOMPLYWTHTHISINFORMATIONCOLLECTIONREQUEST:50.0HRS.FORWARDCOMMENTSREGARDINGBURDENESTIMATETOTHERECORDSANDREPORTSMANAGEMENTSAANCH(P430).(J.S.NUCLEARREGULATORYCOMMISSION.WASHINGTON.OC20555,ANOTO1HEPAPERWORKREDUCTIONPROJECT(3(5001041.OFFICEOFMANAGEMENTANDBUDGET,WASHINGTON,DC20503.FACILITYNAMEll)DOCKETNUMBER(2)L'ERNUMSER(5)PAGE(31R.E.GonnaNuc1earPowerP1antTEXT///maree/reae/en/JI/urer/Iree////ane~HRCFarm355A3/((2)os000244YEARgg93SEOUENTIAINUMSER003REVISIONNUMSER0002OF0XaZ-ZVENTPupaCONDITIONSTheplantwasintheCold/RefuelingShutdownmodewiththereactorinthedefueledcondition.PhaseFive(5)oftheValveImprovementProgram(VIP)wasinprogresswithmajoremphasisontheServiceWaterSystemvalves.Normalvalvedegradationhadbeenobservedintheprevious4phasesoftheVIP.DuringPhaseFive,amoreseriousdegradedconditionwasdiscoveredforCraneModel101XUvalves.Thefollowingisalistingoftherecentproblemsexper-iencedwiththeseCraneModel101XUvalves:0May1990:FirstfailureofaCraneModel101XUvalvewasidentified.Thisfailurewasinanon-safetyrelatedapplication,andwasdocumentedonWorkRequest/TroubleReport(WR/TR)g9000910forServiceWaterSystemvalve4675(ServiceWaterInletIsolationValvetoMainGeneratorHydrogenSideandAirSideSealOilCoolers).0April1991:IndicationofapossiblesecondfailureofaCraneModel101XUvalvewasidentified.Thispossiblefailure,alsoinanon-safetyrelatedapplication,wasdocumentedonWR/TRf9100754forServiceWaterSystemvalve4690(ServiceWaterInletBlockValvetoTurbineLubeOilCooler"B").September1991:.AfterseveraltroubleshootingeffortsasfollowuptoWR/TRf9100754,radiographyofvalve4690,documentedonWR/TRf9122140,confirmsfailureofvalve4690.0April1992:Duringdisassemblyandrepairofvalve4690,thefailuremodeisdeterminedtobethesamefailuremodeasforvalve4675.NRCForm366A(689)I

NRCFORM366A(SJ)9)IAS.NUCLEARREGULATORYCOMMISSIONLICENSEEETREPORT(LER)TEXTCONTINUATIONAPPROVEDOMBNO.3'15001046XPIRES:6/30/92IMATEDBURDENPERRESPONSETOCOMPLYWTHTHISINFORMATIONCOLLECTIONREQUEST:50.0HRS.FORWARDCOMMENTSREGARDINGBURDENESTIMATETOTHERECORDSANDREPORTSMANAGEMENTBRANCH(F430),U.S.NUCLEARREGULATORYCOMMISSION,WASHINGTON,OC20555,ANDTO1HEPAPERWORKREDUCTIONPROJECT(3(500(04).OFFICEOFMANAGEMENTANOBUDGET,WASHINGTON,OC20503.FACILITYNAME(11DOCKETNUMBER(2)LERNUMBER(SlPAGE(3)YEARg@SEQUENTIALNUMSERn.S"REV(SION~/.(NUMBERR.E.GinnaNuclearPowerPlantTEXT/l/macopooo/Jneo/oN/oooad/6ono/HRC%%dnn35643/(12)05000244930030003OF09DESCRIPTIONOFEVENTA.DATESANDAPPROXIMATETIMESOPMAZOROCCURRENCES:oMarch28,1993,1200EST:Eventdateandtime.oMarch28,1993,1200EST:Discoverydateandtime.EVENT:OnMarch28,1993at;approximately1200EST,withthereactorinthedefueledcondition,theMaintenanceDepartmentwasperformingPhaseFive(5)oftheVIP.Asincludedinthe1993VIP,ServiceWaterSystemvalve4669(ServiceWaterInlettoEmergencyDieselGenerators"A"and"B"Crosstie)(safetyrelated)wastoberefurbishedandServiceWatervalve4738(ServiceWaterLoop"B"RootValvetoAuxiliaryBuildingMotorCoolers)(safety'related)wastobereplaced.Valve4738wasplannedforreplacement,vicerefurbishment,duetounavailabilityofrepairparts.Whentheinternalsofthevalveswereexposed,theexistingconditionsrevealedthatthevalvediskhadseparatedfromitsvalvestem.Bothvalvediskswerefoundintheclosedpositionwiththeirstemsseparatedfromthediskandfullyretracted.Thisfailuremodeisundetectableundernormaloperationandwithexistingroutineperiodictesting,.duetoparallelflowpaths.(Thenormalatpowerconditionforthesevalvesis"lockedopen").AlsoduringPhaseFive(5)oftheVIP,specialperformancetestsidentifiedotherServiceWaterSystemvalveswithunexpectedlyhighleakagepastthevalveseatwiththevalveintheclosedposition.Thesevalvesperformanisolationfunction,andthisleakagedegradedtheirisolationcapabilities.NRCForm366A(SJI9) t NRCFORM368A(689)US.NUCLEARREGULATORYCOMMISSIONLICENSEEETREPORT(LER)TEXTCONTINUATIONAPPROVEDOMBNO.3)500104EXPI8ES:E/30/92IMATEDBURDENPERRESPONSETOCOMPLYWTHTHISIFORMATIONCOLLECTIONREOUESTI50J)HRS.FORWARDCOMMENTSREGARDINGBURDENESTIMATETOTHERECORDSANDREPORTSMANAGEMENTBRANCH(F430).U.S.NUCLEARREGULATORYCOMMISSION,WASHINGTON,DC20555,ANDTO1HEPAPERWORKREDUCTIONPROJECT(31504)04).OFFICEOFMANAGEMENTANDBUDGET,WASHINGTON,DC20503.FACII.ITYNAME(I)DOCKETNUMBER(2)YEARLERNUMBER(6)SEQVENTIAI.NVMSE8REVISIONNUMSERPAGE(3)R.E.GinnaNuclearPowerPlantTEXT///moree/Noe/eteqoka/,weaf//I/ona///RCFomI38848/(17losooo2449300300P40FP9C.XNOPERABLESTRUCTUE&SFCOMPONENTSFORSYSTEMSTHATCONTRXBUTEDTOTHEEVENT:D.None.OTHERSYSTEMSORSECONDARYFUNCTIONSAFFECTED:CraneModel101XUvalvesarealsoinstalledintheComponentCoolingWater(CCW)andAuxiliaryFeedwaterSystems.SeeSection(V)(B)formoredetailonvalvesinthesesystems.E.METHODOFDXSCOVERY:TheseeventswerediscoveredduringplannedVIPmaintenanceforthe.1993AnnualOutage.F.OPERATORACTION:As'thesewerecomponentfailuresidentifiedonoutofservicesectionsoftheServiceWaterSystem,noimmediateoperatoractionwasnecessary.GSAFETYSYSTEMRESPONSES:None.XXXCAUSEOR&TENTA.XMMEDXATECAUSETheimmediatecauseofvalves4738and4669heingunknowinglyintheclosedpositionwasduetoaseparationofthevalvediskfromthevalvestem.Theimmediatecauseofexcessiveleakagewasduetothegeneraldeteriorationofisolationvalves.NRCForm388A(689)

NRCFORM388A((W)9)US.NUCLEARREGULATORYCOMMISSIONLICENSEEEITREPORTILER)TEXTCONTINUATIONAPPROVED0MBNO.31504104EXPIRES:4/30/92IMATEDBURDENPERRESPONSETOCOMPLYWTHTHISINFORMATIONCOLLECTIONREQUEST:508)HRS.FORWARDCOMMENTSREGARDINGBURDENESTIMATETOTHERECORDSANDREPORTSMANAGEMENTBRANCH(P4)30),U.S.NUCLEARREGULATORYCOMMISSION,WASHINGTON,DC20555,ANDTO1HEPAPERWORKREDUCTIONPROJECT(31504104).OFFICEOFMANAGEMENTANDBUDGET,WASHINGTON,DC20503.FACILITYNAMEI'I)DOCKETNUMBER(2)YEARLERNUMBER(8)SEQUENTIAL3<(NUMBERIuyREVISIONNVMERPAGE(3)R.f.GinnaNuclearPowerPlantTEXT///Ruuo4pooobnoduled,uooeI/cNone/N/ICFoun3%43/l)T)osooo244930030005O"09B.INTERMEDIATECAUSE:Thestemanddiskofvalves4738and4669hadseparatedduetoavarietyofcorrosioneffects.Isolationvalvedeteriorationwasduetoavarietyoffactors,includingcorrosion,wastage,andenvironmen-talconditions,resultinginvalvesnotfullyisola-ting.ROOTCAUSE.Theunderlyingcauseofthecorrosioneffectsonvalves4738and4669wasduetotheuseofdissimilarmetalsinthemanufactureofthestemanddisk,combinedwithprolongedexposuretorawservicewateranddifferentialaerationcell(concentrationcell)corrosionduetostagnantconditionssurroundingtheteeslotareainthevalvebonnet.Theunderlyingcauseofthevalvesnotfullyisolatingwasduetoprolongedexposuretotheerosiveandcorrosiveeffectsofrawservicewater.ANALYSISOPEVENTTheseeventsarebeingvoluntarilyreportedusingtheguidanceofNUREG-1022(LicenseeEventReportSystem),andSupplement1toNUREG-1022.WhilethesafetysignificanceofthesespecificeventsdoesnotrequiresubmittalofaLicenseeEventReport,thesetypesofdegradationcouldbesafety-significantatotherplants,dependingonthevalveapplications.ThisreportisintendedtoalertotherutilitiesandtheNRCofproblemsinapplicationswherecorrosioncanoccurbetweenthevalvestemanddisk,inrawwaterapplications,andofthepotentialfordegradationofisolationcapabilitiesduetovalvedeterioration.Theseeventsarerelatedto,butdonotmeet,thereportingrequirementsof10CFR50.73,item(s)(2)(v)and(a)(2)(vi);whichrequiresreportingofconditions,"thatalonecouldhavepreventedthefulfillmentofthesafetyfunction",butwhere,"individualcomponentfailuresneednotbereported".NRCForm388A(889)

NRCFORM366A(64)9)UB.NUCLEARREGULATORYCOMMISSIONLLICENSEEETREPORT(LER)TEXTCONTINUATIONAPPROVEDOMBNO.31500104EXPIRES:4/30/92IMATEDBURDENPERRESPONSETOCOMPLYWTHTHISINFORMATIONCOLLECTIONREQUEST:60.0HRS.FORWARDCOMMENTSREGARDINGBURDENESTIMATETOTHERECORDSANDREPORTSMANAGEMENTBRANCH(P4)30),U.S.NUCLEARREGULATORYCOMMISSION,WASHINGTON,OC20555,ANDTO1HEPAPERWORKREDUCTIONPROJECT(31504))04).OFFICEOFMANAGEMENTANDBUDGET,WASHINGTON,OC20503.FACILITYNAME(IlDOCKETNUMBER(2)YEARLERNUMBER(6):"'jSEQUENTIAL'..':jPIIEYIEIONN'UMBErlN?ArrUM66rlPAGE(3)R.E.GinnaNuclearPowerPlantTEXT///mare4/ra>>/4rer/rr/rerLIree/I/orre/HRCAvm36643)(17)p5ppp2449300300060F09Anassessmentwasperformedconsideringboththesafetyconsequencesandimplicationsofthiseventwiththe.followingresultsandconclusions:Aspartofthisassessment,anevaluationwasperformedconcerningtheServiceWaterSystemoperability,priortothe1993AnnualOutage,duetotheeffectsofServiceWaterSystemvalveleakagefromthevalvesdesignedtoisolatethenon-essentialservicewaterduringanaccidentwithlossofoffsitepowerandduetotheeffectsofthetwofailedcloseessentialservicewatercrosstievalves.Theevaluationconsidered3accidents(i.e.ContainmentIntegrity,LossOfCoolantAccident(LOCA)andLOCARecirculation)usingthefollowingassumptions:oTotalservicewaterisolationvalveleakageofapproximately1100gpm,basedonadetailedresultsof.specialperformancetestsconductedduringthe1993outage.oOneservicewaterpumpoperating.oSinglefailureofthe"A"EmergencyDieselGenerator.oLossofoffsitepower.Basedontheaboveassumptionsthemainthrustoftheevaluationwastoinvestigatewhethertheidentifiedvalvefailuresandleakagecouldhaveadverselyimpactednuclearsafetyduetochangingtheservicewaterflowtothecriticalcomponentsforrequiredaccidentcooling.ThecriticalcomponentsconsideredweretheEmergencyDieselGeneratorCoolers,theContainmentRecirculationFanCoolingCoils,theContainmentRecirculationFanMotorCoolersandduringtherecirculationphaseoftheaccident,theComponentCoolingWaterheatexchangers.Conclusionsfromtheaboveevaluationindicatethatallcriticalcomponentflowswereacceptable.NRCForm366A(689)

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NACFOAM366A(669)US.NUCLEARREGULATORYCOMMISSIONLICENSEEETREPORTILERITEXTCONTINUATIONAPPROVEDOMBNO.31500104EXPIRES:E/30/92IMATEDBURDENPERRESPONSETOCOMPLYWTHTHISINFORMATIONCOLLECTIONREQUEST:50A)HAS.FORWARDCOMMENTSREGARDINGBURDENESTIMATETOTHERECORDSANDREPORTSMANAGEMENTBRANCH(P430),U.S.NUCLEARREGULATORYCOMMISSION.WASHINGTON,DC20555.ANDTO1HEPAPERWORKREDUCTIONPROJECT(31504104),OFFICEOFMANAGEMENTANDBUDGET,WASHINGTON,OC20503.FACILITYNAME(1)DOCKETNUMBER(2)YEARLERNUMBER(5)SEQUENTIALNVMERREVISIONNUMBERPAGE(3)R.E.GinnaNuclearPowerPlantTEXT//Imacspace/tmgv/nnt,IIsPada//I/one/NRCFnmI3//549/(17)osooo244930030007OF09ThepotentialforinterruptionofServiceWaterflowtotheSafetyInjection(SI)pumpthrustbearingswasevalu-ated.ThisevaluationdeterminedthatflowfromtheredundantServiceWaterlinetotheSIpumpswasadequateusingtheassumptionoutlinedabove.Basedontheabove,itcanbeconcludedthatthepublic'shealthandsafetywasassuredatalltimes.V.CORRECTIVEACTIONA.ACTIONTAKENTORETURNAFFECTEDSYSTEMSTOPRE-EVENTNORMALSTATUS:ThefailedCraneModel101XUServiceWatervalveswerereplacedwithqualifiedsparesofadifferentdesignandmaterialcomposition,weretestedsatis-factorilyandwerereturnedtoservice.OtherdegradedServiceWatervalveswerealsoreplacedwithqualifiedspares.B.ACTIONTAKENORPLANNEDTOPREVENTRECURRENCE.AspartoftheVIPandtopreventrecurrenceoftheServiceWaterSystemvalvefailures,allotherCraneModel101XUvalvesintheServiceWatersystemwereassessedforfunctionalityandthosevalvewarrantingreplacementwerereplacedduringthe1993AnnualOutage.Inaddition,selectedCraneModel101XUvalvesintheCCWandAuxiliaryFeedwaterSystemswereinspected,withsatisfactoryresults.NRCFonII366A(669)

EI' NRCFORM366A(64)9)US.NUCLEARREGULATORYCOMMISSIONLICENSEEETREPORT(LER)'EXTCONTINUATIONAPPROVEDOMBNO.31500104EXPIRES:4/30/92IMATEDBURDENPERRESPONSETOCOMPLYWTHTHISINFORMATIONCOLLECTIONREOUEST:50JIHRS.FORWARDCOMMENTSREGARDINGBURDENESTIMATETOTHERECORDSANDREPORTSMANAGEMENTBRANCH(P430),U.S.NUCLEARREGULATORYCOMMISSION,WASHINGTON,DC20555,ANDTOTHEPAPERWORKREDUCTIONPROJECT(31500104),OFFICEOFMANAGEMENTANDBUDGET,WASHINGTON.DC20503.FACILITYNAME(1)DOCKETNUMBER(2)YEARLERNUMBERIS)SEOVENTIAL??X%NUMBER'4?".REYlSIONNVMSEIIPAGE(3)R.E.GInnaNuclearPowerPlantTEXT///mme4/Joco/4nqukat,uoo//I/ooo/N/ICFoon3664'4/I)7)osooo244930030008OF0AspartoftheVIPandtopreventrecurrenceoftheServiceWaterSystemvalvetypefailures,allremainingCraneModel101XUvalvesintheServiceWaterSystemarescheduledtoberefurbishedorreplacedduringthe1994AnnualOutage.Inaddition,remainingCraneModel101XUvalvesintheCCWandAuxiliaryFeedwaterSystemswillbeinspectedin1994.Iftheinspectionresultswarrantrefurbishmentorreplacement,thevalveswillbereplaced.AsaresultoftestsperformedontheServiceWaterSystem,thescopeofmaintenancewasincreased,andotherServiceWaterSystemvalveswerealsoinspectedduringthe1993Outage.Valvesfoundtobeexcessivelydeterioratedwerereplaced,andothervalveswererefurbished,ifwarranted.Inspection/refurbishm-ent/replacementwillcontinueduringthe1994and1995AnnualOutages.BasedontheresultsoftheVIPinspection/refur-bishment/replacement,apreventativemaintenancefrequency,forvalvesintheServiceWaterSystem,willbeestablishedaspartoftheReliabilityCenteredMaintenanceprocess.ADDITIONALINFORMATIONFAILEDCOMPONENTS:ThefailedCraneModel101XUvalvesweremanufacturedbyCraneCompany.B.PREVIOUSLERsONSIMILARLRG94TS:AsimilarLEReventhistoricalsearchwasconductedwiththefollowingresults:NodocumentationofsimilarLEReventswiththesamerootcauseatGinnaNuclearPowerPlantcouldbeidentified.NRCForm366A(669)

NRCFORM368A(889)US.NUCLEARREGULATORYCOMMISSIONLICENSEEETREPORT(LER)TEXTCONTINUATIONAPPROVEOOM6NO.3)500)086xpIREs:8/30/92IMATEDBURDENPERRESPONSETOCOMPLYWTHTHISINFORMATIONCOLLECTIONREOUEST:50.0HRS.FORWARDCOMMENTSREGARDINGBURDENESTIMATETOTHERECORDSANOREPORTSMANAGEMENTBRANCH(M)30),U.S.NUCLEARREGULATORYCOMMISSION,WASHINGTON.OC20555,ANDTO1MEPAPERWORKREDUCTIONPROJECT(31600'l04),OFFICEOFMANAGEMENTANDBUDGET,WASHINGTON,OC20503.FACILITYNAME(1)DOCKETNUMBER(2)YEARLERNUMBER(8)jXB>SEQUENTIALyN(NVMSSR~@NVMSSIIPAGE(3)R.E.GinnaNuclearPowerPlantTEXT///maree/reoe/emr/rrka/weaA////one//r/RCFomr38683/(17)osooo2443-03-0009OF0C.SPECIALCOMMENTS:TheindustrywasinformedofthesefailuresviaNuclearNetworkonApril8,1993.AreportofcomponentfailureswillbesubmittedtotheNPRDSSystem.Thesefailuresmayalsobeundetectableatotherplants,undernormaloperationandwithexistingroutineperiodictesting,duetoparallelflowpaths.FailuresatGinnawereonlydetectedduringvalvedisassemblyand/orreplacement,orasaresultofspecialperformancetests.Otherutilitiesmaywanttoconsiderthebenefitsofenhancedtestingormaintenanceevaluationstodetectthesetypesoffailures.NRCForm388A(689)