ML17262A832

Proposed Tech Specs Re Snubber Visual Insp Schedule

ML17262A832
Person / Time
Site:	Ginna
Issue date:	04/23/1992
From:	ROCHESTER GAS & ELECTRIC CORP.
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ML17262A830	List: ML17262A828 ML17262A831 ML17262A832
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NUDOCS 9205060110
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ATTACHMENT ARevisetheTechnical Specification pagesasfollows:Remove3~1314.14-14.14-24..14-34.14-44.14-54..14-64.14-74.14-8Insert3%1314.14-14.14-24.14-34.14-44.14-54.14-64.14-74.14-84-.14-94.14-10'9205060110 920423PDRADOCK05000244PPDR 3.13SnubbersLimitinCondition for0eration3..13.1WithRCSconditions abovecoldshutdown, allsafety-related 3.13.2snubbersshallbeoperable.

Thisspecification doesnotapplytothosesnubbersinstalled onnonsafety-related systemsifthesnubberfailure,and,aresulting failureofthesupported.

nonsafety-related.

systemshowntobecausedbythatsnubberfailure,wouldhavenoadverseeffectonanysafety-related system.ActionWithoneormoresnubbersinoperable, within72hoursreplaceorrestoretheinoperable snubber(s) tooperablestatusand,performanengineering evaluation perSpecification 4.14.1fonthesupported.

component ordeclarethesupported systeminoperable and.followtheappropriate actionstatement forthatsystem.BasisSnubbersarerequiredtobeoperabletoensurethatthestructural integrity ofthereactorcoolantsystemandallothersafety-related systemsismaintained duringand.following aseismicorothereventinitiating dynamicloads.Snubbersmaybereplacedbyrigidstructural supports(bumpers) providedananalysisisperformed todemonstrate thatappropriate acceptance criteriaaresatisfied fordesignbasisseismicand.pipebreakeventsandprovidedthatthebumpersareinspected.

periodically inamannerappropriate forrigidstructural supports.

Amendment No.3~131Proposed 4.144.14.1SnubberSurveillance ReirementsEachsnubberrequiredbySpecification 3.13tobeOPERABLEshallbedemonstrated.

OPERABLEbytheperformance ofthefollowing inservice inspection programinadditiontotherequirements ofSpecification 4.2.a~Insection.esAsusedinthisspecification, "typeofsnubber"shallmeansnubbersofthesamedesignandmanufacturer.,

irrespective ofcapacity.

b.VisualInsectionscSnubbersarecategorized asinaccessible oraccessible duringreactoroperation.

Eachofthesecategories (inaccessible andaccessible) maybeinspected independently according tothescheduledetermine byTable4.14-1.Thevisualinspection intervalforeachtypeofsnubbershallbedetermined baseduponthecriteriaprovided.

inTable4.14-1.VisualXnsectionAccetanceCriteriaVisualinspections shallverifythat(1)thesnubberhasnovisibleindications ofdamageorimpairedOPERABILITY, (2)attachments tothefoundation orAmendment No.4.14-1Proposed supporting structure arefunctional, and(3)fasteners fortheattachment ofthesnubbertothecomponent andtothesnubberanchorage arefunctional.

Snubberswhichappearinoperable asaresultofvisualinspections shallbeclassified asunacceptable andmaybereclassified acceptable forthepurposeofestablishing thenextvisualinspection

interval, providedthat:(1)thecauseoftherejection isclearlyestablished andremediedforthatparticular snubberandforothersnubbers, irrespective oftypethatmaybegenerically susceptible; or(2)theaffectedsnubberisfunctionally tested.intheas-foundcondition anddetermined OPERABLEperSpecification 4.14.1e.Allsnubbersfoundconnected toaninoper-able commonhydraulic fluidreservoir shallbecountedasunacceptable fordetermining thenextinspection interval.

Areviewandevaluation shallbeperformed anddocumented tojustifycontinued operation withanunacceptable snubber.Ifcontinued operation cannotbejustified, thesnubbershallbedeclaredinoperable and.theACTIONrequirement shallbemet.Amendment No.374.14-2Proposed TABLE4.14-1SNUBBERVISUALINSPECTION INTERVALPopulation orCategoryNUMBEROFUNACCEPTABLE SNUBBERS(Ref.Note7)ColumnAColumnBColumnCExtendIntervalRepeatIntervalReduceInterval(Notes1and2)(Notes3and6)(Notes4and6)(Notes5and6)801001502003004005007501000orgreater122.029244056364878109Note1:Thenextvisualinspection intervalforasnubberpopulation orcategorysizeshallbedetermined baseduponthepreviousinspection intervalandthenumberofunacceptable snubbersfoundduringthatinterval.

Snubbersmaybecategorized, basedupontheiraccessibility'uring poweroperation, asaccessible orinaccessible.

Thesecategories maybeexaminedseparately orjointly.However,thisdecisionmustbeAmendment No.4.14-3Proposed f

Note2:Note3:Note4:Note5:Note6:Note7:documented beforeanyinspection andshallbeusedasthebasisuponwhichtodetermine thenextinspection intervalforthatcategory.

Interpolation betweenpopulation orcategorysizesandthenumberofunacceptable snubbersispermissible.

UsenextlowerintegerforthevalueofthelimitforColumnsA,B,orCifthatintegerincludesafractional valueofunacceptable snubbersasdetermined byinterpolation.

Ifthenumberofunacceptable snubbersisequaltoorlessthanthenumberinColumnA,thenextinspection intervalmaybetwicethepreviousintervalbutnotgreaterthan48months.Ifthenumberofacceptable snubbersisequaltoorlessthanthenumberinColumnBbutgreaterthanthenumberinColumnA,thenextinspection intervalshallbethesameasthepreviousinterval.

Ifthenumberofunacceptable snubbersisequaltoorgreaterthanthenumberinColumnC,thenextinspection intervalshallbetwo-thirds ofthepreviousinterval.

However,ifthenumberofunacceptable snubbersislessthanthenumberinColumnCbutgreaterthanthenumberinColumnB,thenextintervalshallbereducedproportionally byinterpolation, thatis,thepreviousintervalshallbereducedbyafactorthatisone-third oftheratioofthedifference betweenthenumberofunacceptable snubbersfoundduringthepreviousintervalandthenumberinColumnBtothedifference inthenumbersinColumnBandC.Theprovisions ofSpecification Section4.0areapplicable forallinspection intervals uptoandincluding 48months.Todetermine thenextsurveillance

interval, anunacceptable snubbermaybereclassified asacceptable ifitcanbedemonstrated thatthesnubberisoperableinitsas-foundcondition byperformance ifafunctional testandifitsatisfies theacceptance criteriaforfunctional testing.Amendment No.4.14-4Proposed 04 4.14.1.dFunctional TestsAtleastonceper18monthsduringshutdown, arepresentative sample(atleast10-oofthesnubbersrequiredbySpecification 3.13)shallbefunctionally tested.eitherinplaceorinabenchtest.Foreachsnubberthatdoesnotmeetthefunctional testacceptance criteriaof.Specification 4.14.1e,anadditional 10%ofthesnubbersshallbefunctionally testeduntilnomorefailuresarefoundoruntilallsnubbershavebeenfunctionally tested.Therepresentative sampleselectedforfunctional testingshall,asfaraspractical, includethevariousconfigurations, operating environments, rangeofsizesandcapacities ofsnubbers.

Inadditiontotheregularsample,snubbersplacedinthesamelocations assnubberswhichfailedthepreviousfunctional testshallberetestedatthetimeofthenextfunctional test.Additionally, ifafailedsnubberhasbeenrepairedandreinstalled inanotherlocation, thatfailedsnubbershallalsoberetested.

Thesesnubbersshallnotbeincludedintheregularsample.Ifduringthefunctional testing,additional samplingisrequireddueto,failureofonlyonetypeofsnubber,thefunctional testingresultsshallbereviewedatthattimetodetermine ifadditional samplesshouldbelimitedtothetypeofsnubberwhichhasfailedthefunctional testing.Amendment No.4.14-5Proposed 4.14.1.e.

Functional TestAccetanceCriteriaThesnubberfunctional testshallverifythat:1)Activation (restraining action)isachievedwithinthespecified rangeinbothtensionandcompression; 2)Snubberbleed,orreleaseratewhererequired.,

ispresentinbothtensionand,compression, withinthespecified range;3)Whererequired, theforcerequiredtoinitiateormaintainmotionofthesnubberiswithinthespecified rangeinbothdirections oftravel;and4)Forsnubbersspecifically requirednottodisplaceundercontinuous load,theabilityofthesnubbertowithstand loadwithoutdisplacement isverified.

Testingmethodsmaybeusedtomeasureparameters indirectly orparameters otherthanthosespecified ifthoseresultscanbecorrelated tothespecified parameters throughestablished methods.Functional TestFailureAnalsisAnanalysisshallbemadeofeachfailuretomeetthefunctional testacceptance criteriatodetermine thecauseofthefailure.TheresultsofthisanalysisAmendment No.34.14-6Proposed shallbeused,ifapplicable, inselecting snubberstobetestedinanefforttodetermine theoperability ofothersnubbers, irrespective oftype,whichmaybesubjecttothesamefailuremode.Forthespecificcaseofasnubberselectedforfunctional testingwhicheitherfailstoactivateorfailstomove,i.e.,frozen-in-place,the.causewillbeevaluated and,ifcausedbymanufacturer ordesigndeficiency, allsnubbersofthesametypesubjecttothesamedefectshallbefunctionally testedorevaluated inamannertoensuretheiroperability.

Anytestingperformed aspartofthisrequirement shallbeindependent oftherequirements statedinSpecification 4.14.1dforsnubbersnotmeetingthefunctional testacceptance criteria.

Foranysnubbersfoundinoperable, anengineering evaluation shallbeperformed onthecomponents towhichtheinoperable snubbersareattached.

Thepurposeofthisengineering evaluation shallbetodetermine ifthecomponents towhichtheinoperable snubbersareattachedwereadversely affectedbytheinoperability ofthesnubbersinordertoensurethatthecomponent remainscapableofmeetingthedesignedservice.Amendment No.4.14-7Proposed 4.14.1.gSnubberSealServiceLifeMonitorin Thesealservicelifeofhydraulic snubbersshallbemonitored.

andsealsreplacedasrequiredtoensurethattheservicelifeisnotexceededbetweensurveillance inspections duringaperiodwhenthesnubberisrequiredtobeoperable.

Thesealreplacements shallbedocumented andthedocumentation shallberetainedinaccordance withTechnical Specification 6.10.2.BasisSnubbersareprovidedtoensurethatthestructural integrity ofthereactorcoolantsystemandallothersafetyrelatedsystemsismaintained duringandfollowing aseismicorothereventinitiating dynamicloads.Thevisualinspection frequency isbasedonthenumberofunacceptable snubbersfoundduringtheprevious'nspection inproportion tothesizesofthevarioussnubberpopulations orcategories.

Asnubberis-considered unacceptable ifitfailstheacceptance criteriadelineated bySpecification 4.14.1.c.

Thevisualinspection intervalisbaseduponthepreviousinspection intervalandmaybeaslongastwofuelcycles,nottoexceed48months,depending onthenumberofunacceptable snubbersfoundduringthepreviousvisualinspection.

Amendment No.4.14-8Proposed

ttUnacceptable snubbersshallbeevaluated todetermine iftheyareinoperable.

Forinoperable snubberstheapplicable actionrequirements shallbemet.Whenasnubberisfoundinoperable, anengineering evaluation ofthesupported component isperformed inordertodetermine ifanysafety-related component orsystemhasbeenadversely affected.

bytheinoperability ofthesnubber.Thisevaluation isinadditiontothedetermination ofthesnubbermodeoffailure.Theengineering evaluation shalldetermine whetherornotthesnubberfailurehasimpartedasignificant effectonorcauseddegradation ofthesupported component orsystem,toensuretheyremaincapableofmeetingthedesigned, service.Whenthecauseoftherejection ofasnubberisclearlyestablished..

and,remediedforthatsnubberandforanyothersnubbersthatmaybegenerically susceptible, andverifiedbyinservice functional testing,thatsnubbermaybeexemptedfrombeingcountedasinoperable.

Generically susceptible snubbersarethosewhichareofaspecificmakeormodelandhavethesamedesignfeaturesdirectlyrelatedtothesnubberrejectedorarethosewhicharesimilarly locatedorexposedtothesameenvironmental conditions suchastemperature, radiation, and.vibration.

Todetermine thenextsurveillance

interval, anunacceptable snubbermaybereclassified asacceptable ifitcanbedemonstrated thatthesnubberisoperableinitsas-foundcondition byperformance ofafunctional testandifitsatisfies theacceptance criteriaforfunctional testing.Amendment No.4.14-9Proposed Toprovideassurance ofsnubberfunctional reliability, arepresentative sampleoftheinstalled snubberswillbefunctionally testedduringplantshutdowns atlessthanorequalto18monthintervals.

Observedfailuresofthesesamplesnubbersshallrequirefunctional testingofadditional units.Hydraulic snubbersandmechanical snubbersmayeachbetreatedasadifferent entityfortheabovesurveillance programs.

Theservicelifeofasnubberisevaluated viamanufacturer inputandengineering information throughconsideration ofthesnubberserviceconditions andfunctional designrequirements.

Theonly'snubbercomponents withservicelivesnotexpectedtoexceedplantlifearesealsand,o-ringsfabricated fromcertainsealmaterials.

Therefore, asealreplacement programisrequiredtomonitorsnubbersealando-ringservicelifetoassuresnubberoperability isnotdegradedduetoexceeding component servicelife.Amendment No.4.14-10Proposed ATTACHMENT BDESCRIPTION Theproposedamendment redefines thesnubbervisualinspection schedulepursuanttoguidancecontained inGenericLetter90-09.ThecurrentformatofSpecification 4.14.1willalsobemodifiedtoparalleltheformatdelineated inthemodelcontained.

inGenericLetter90-09.Therefore, someeditorial changes,inadditiontochangestothebasis,weremadetoensureconsistency.

Thecurrentschedule, described inTechnical Specification 4.14.1a,isbasedonlyonthenumberofinoperable snubbersfoundduringthepreviousinspection, irrespective ofthesizeofthesnubberpopulation.

Thecurrentinspection intervalisbasedonafuelcycleofupto18months,withamaximumallowable extension nottoexceed25percentofthespecified surveillance interval.

Theinspection intervaldependsonthenumberofunacceptable snubbersfoundduringthepreviousvisualinspection.

Thealternative inspection

schedule, described inGenericLetter90-09,isbasedonthenumberofunacceptable snubbersfoundduringthepreviousinspection inproportion tothesizesofvarioussnubberpopulations orcategories.

Asnubberisconsidered unacceptable, inbothcases,ifitfailstheacceptance criteriaofthevisualinspection.

Thealternative inspection intervalisbasedonafuelcycleofupto24monthsand.maybeaslongastwofuelcycles,or48monthsforplantswithotherfuelcyclesdepending onthenumberofunacceptable snubbersfoundduringtheprevious.

visualinspection.

SYSTEMSANDCOMPONENTS AFFECTEDSafety-Related Hydraulic andMechanical SnubbersSAFETYFUNCTIONOFAFFECTEDSYSTEMSANDCOMPONENTS ThesafetyfunctionofSurveillance Requirement 4.14.1a(visualinspection reguirement),

istoensurethatnoobservable deficiencies existwithanysnubberinstallation thatwouldrenderasnubberinoperable.

Snubbersarerequiredtoensurethatthestructural integrity ofthereactorcoolantsystemandallothersafetyrelatedsystemsismaintained duringandfollowing aseismicevent.Snubbers, ordynamicrestraints, areusedtorestrainpipingorequipment duringseismiceventsortransient loads,yettheyallowrelatively unrestrained.

movementofthepiping/component duringnormalheatuporcooldownoperations.

EFFECTSONSAFETYSnubberinservice inspection requirements consistofvisualinspection andfunctional testing.Visualinspection isintendedtodetectpotential impairedoperability causedbyleakage,corrosion ordegradation duetoenvironmental exposure.

Functional testingtypically involvesremovingthesnubberandtestingonaspecifically-designed teststandtoverifyitsabilitytooperatewithinspecified performance limits.Ingeneral,functional testingisintendedtoprovidea95-oconfidence level,that90to100percentofthesnubbersareoperablewithinacceptable limits.Theperformance ofthevisualinspection isaseparateprocesswhichiscomplimentary tothefunctional testingprogramandprovidesadditional confidence insnubberoperability.

Rochester GasandElectricCorporation hascompareddatagathered.

onGinnaStation's hydraulic andmechanical snubberstothatreportedbyBrookhaven NationalLaboratory (BNL).TheBNLreportwaspreparedfortheCommission, "Development ofAlternative SnubberSurveillance Requirements:

Recommended InterimSnubberSurveillance Plan,"datedJune12,1989insupportofGenericLetter90-09.Themethodology presented intheBNLreportisthebasisforGenericLetter90-09.TheresultsofthedatagatheredonGinnaNuclearPowerStationcomparedfavorably tothedataevaluated byBNL.Theresults,forbothGinnaandBNL,showedthatthepercentfailureratesfoundforvisuallyexaminedandfunctionally testedsnubbersarelow.ThefailureratesforGinna'svisualexaminations alsocomparedfavorably tofunctionally testedsnubbers.

Thevisualinspections hadfailureratesof6.0%and4.0%forthehydraulic andmechanical snubbersrespectively.

Thecorresponding failureratewhensnubbersweresubjected toanactualtestwas2.2%.Theresultsdescribed abovearedocumented inGinnaSafetyEvaluation numberNSL-0000-SE004.

Thissafetyevaluation wasreviewedandapprovedbyGinna'sPlantOperations ReviewCommittee (PORC).Itisapparent, fromtheresultsforGinna,thatextending thevisualinspection intervalpursuanttotheguidancecontained inGenericLetter90-09isreasonable.

Itisemphasized that,basedonthereliability analysisforextension ofthevisualinspection intervalpresented intheBNLstudy,themaximumpermissible numberofinoperable snubberssatisfying thereliability criterion dependsonthegroupsizeandthefutureinspection period.Thus,thereduction inmarginofsafetyisconsidered tobeinsignificant.

Thisproposed.

amendment complieswiththesnubberreliability criterion thataminimumof90%ofthesnubbers(inthegroup)beoperableinthenextinspection period.Further,theproposedchangecomplieswiththeguidancecontained.

inGenericLetter90-09.

10CFR50.92 EVALUATION TheproposedchangeintheGinnaTechnical Specifications doesnotinvolveasignificant hazardconsideration.

Thebasisforthisdetermination isdocumented inGinnaSafetyEvaluation numberNSL-0000-SE004.Thissafetyevaluation wasreviewedandapprovedbyGinna'sPlantOperations ReviewCommittee (PORC).Thisevaluation confirmed.

thathistorical maintenance andsurveillance dataforsnubbersatGinnadoesnotinvalidate anextension totheexistinginspection

interval, i.e.RGGE'sexperience isconsistent withindustryexperience.

Furthersupportforthebasisfortheabovedetermination isasfollows:Thereisnosignificant increaseintheprobability orconsequences ofanaccidentpreviously evaluated becauseaccidentconditions andassumptions arenotaffectedbytheproposedTechnical Specification change.Theeffectontheavailability ofthesnubbersduetoanincreaseinthevisualinspection intervalhasbeenshowntobenegligible.

Further,functional testingaloneassures,witha95-oconfidence level,thatatleast90-oofthesnubbersareoperablewithoutanyvisualinspection, asassuredbyTechnical Specification 4.14.1c(changedto4.14.1dpertheproposed.

amendment).

Thiswillensurethatsystemreliability remainsessentially unchanged.

Furthermore,.

theproposedchangewillreducefutureoccupational radiation exposure.

Thepossibility ofanewordifferent kindofaccidentfromanyaccidentpreviously evaluated isnotcreated,.

Inmattersrelated.tonuclearsafety,allaccidents areboundedbypreviousanalysis.

Theproposedchangedoesnotadd.toormodifyanyequipment orsystemdesignnordoesitinvolveanychangesintheoperation of-anyplantsystem.Theabsenceofahardwarechangemeansthattheaccidentinitiators remainunaffected, sonouniqueaccidentprobability iscreated.Theproposedamendment doesnotinvolveasignificant reduction inthemarginofsafetyasdefined.inthebasisforanyTechnical Specification becausetheproposed:

amendment willcontinuetoensure,with95-oconfidence, thatatleast90percentofthesnubbersareoperable, asassuredbythecalculations reportedintheBNLreportwhichisthebasisforGenericLetter90-09.Therefore, thefunctionofthetotalpopulation ofsnubbersisreasonably assured.Equipment reliability willbemaintained.

andnoLimitingCondition forOperation (LCO)orLimitingSafetySystemSetpoint(LSSS)wouldbeaffected.

Thus,thereduction inmarginofsafetyisconsidered tobeinsignificant.

CONCLUSION Onthebasisoftheabove,RG&Ehasdetermined thattheamendment requestdoesnotinvolveasignificant hazardsconsideration.