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{{#Wiki_filter:REACTORCOOLASYSTEMSURVEILLANCEREOUIRENENTSContinued5.Oefectmeansanimperfectionofsuchseveritythatitexceedstheplugginglimit.Atubecontainingadefectisdefective.Anytubewhichdoesnotpermitthepassageoftheeddy-currentinspectionprobeshallbedeemedadefectivetube.L.whichthetubeshallberemovedfromservicebecauseitmaybecomeunserviceablepriortothenextinspectionandisequalto40&fthenominaltubewallthickness.7.UnserviceabledescribestheconditionofatubeifitIstructuralintegrityintheeventofanOperatingBasisEarthquake,aloss-of-coolantaccident,orasteamlineorfeedwaterlinebreakasspecifiedin4.4.5.3.c,above,S.TubeInspectionmeansaninspectionofthesteamgeneratortubefromthepointofentry(hotlegside)completelyaroundtheU-bendtothetopsupportofthecoldleg.b.ThesteamgeneratorshallbedeterminedOPERABLEaftercompletingthecorrespondingactions(plugalltubesexceedingtheplugginglimitandalltubescontainingthrough-wa11cracks)requiredbyTable4.4-2.4.4.5.5Reportsa~Followingeachinserviceinspectionofsteamgeneratortubes,thenumberoftubespluggedineachsteamgeneratorshallbereportedtotheCoomissionwithin15days.b.ThecompleteresultsofthesteamgeneratortubeinserviceinspectionshallbeincludedintheAnnualOperatingReportfortheperiodinwhichthisinspectionwascompleted.Thisreportshallinclude:1.Numberandextentoftubesinspected.2.Locationandpercentofwall-thicknesspenetrationforeachindicationofanimperfection.3.Identificationoftubesplugged.ammo000338IPDR'ST.LUCIE-UNIT1860609022idp8PDRADOCK0p3/44-8~Cyc/e>llmr~g~s/o~~;~,ovMud~~~//q<p/~c4d.J/cp<o4~v~"8'p'C<4d<<)~uF.  
{{#Wiki_filter:REACTORCOOLASYSTEMSURVEILLANCE REOUIRENENTS Continued 5.Oefectmeansanimperfection ofsuchseveritythatitexceedstheplugginglimit.Atubecontaining adefectisdefective.
~~Attachment2St.LucieUnit1DocketNos.50-335EmergencyLicenseAmendmentSteamGeneratorPluinLimitSAFETYEVALUATIONThreesteamgeneratortubeswereremovedfromtheAsteamgeneratorofSt.LucieUnit1(PSL-1)duringtheOctober-December1985outage.ThesewerethensenttoBRWforexaminationinordertobettercharacterizetheeddycurrent(ET)indicationsnotedduringthe1980and1985exams.ThesummaryofthelaboratoryworkanditscorrelationtothefieldETresultsareshownontheattachedtable.Thepresenceofgrainboundarydegradationintheformofintergrannularattack(IGA)withsomestresscorrosioncracking(SCC)causedareviewofallthe1985ETdata,andahistoricalreviewofapopulationofdefects,DistortedSupportSignals(DSS)andUndefinedSignals(UDS)aswellas1980-1985pluggedtubes.Additionally,asampleofgreaterthan50%ofdistortedsignalswerecomparedtothe1980datatoassessgrowth.UsingtheBdcWresultsasanindicatortheresultsofthe1985ETexamrevealedthepresenceofseventeenindicationshavingdepth,OOFo.TheseindicationshadtypicallybeenclassifiedaseitherDSSorUDS.WhiledirectcomparisonsofpreviousETdataaredifficultduetotheuseofdifferingequipmentandtechniques,thefollowingconclusionscanbereached:a)Thereisnosignificantchangeinindicationdepthorsignalamplitudebetweenthe1980and1985data.b)Indicationscanbeidentifiedincertaintubesasearlyas1981inthemajorityofcases.Asmallnumbercanbetrackedto1979.TheindustrydataonIGA/SCCdemonstratesthatthetubematerialbelowthesurfaceareaofuniformlydegradedIGA/SCCremainssoundanddoesnotsufferfromincipientdegradationinthegrainboundaries.TestshaveshownthattubeswithIGAwillsustainpressuredifferentialssubstantiallygreaterthanpredictedduringtheworstcasedesignbasisaccident(MSLB)priortoburst.Testinghasalsoshownthatthroughwallcracksof1inchinlengthleakbeforebreak.InordertoverifytheindustryresultsforPSL-l,samplesoftubingwereobtainedfromCEforthepurposeofleakratetesting.ThetestsrunatChattanoogausedthru-wallcracksof3/8",15/16",andIYi"inlengthfortheleak-before-breaktest.TheresultsdemonstratethattheleakageofthroughwallcracksofthesizeseenonPSL-1postMainSteamLineBreak(MSLB)are  
Anytubewhichdoesnotpermitthepassageoftheeddy-current inspection probeshallbedeemedadefective tube.L.whichthetubeshallberemovedfromservicebecauseitmaybecomeunserviceable priortothenextinspection andisequalto40&fthenominaltubewallthickness.
~CIlItI'C<<C,4'r,C.~4,,(.UIr~CI'lfCI<<W4"4I'4WI'<<'<<(('=lfn.wfl4aC('r,4c'((rg(<<"t'(I'W'r<<I<<fh,,If'"'I(~<<I*('<<(~X wellbelowthoseassumedintheSafetyEvaluation.TheseresultsareconservativeinthatthemaximumcracklengthseenatPSL-1isapproximatley.6".InadditionbursttestsrunonCEtubingfor3"long,fullycircumferentialIGAverifythatIGAat70FocouldwithstandovertwicetheMSLBpressuredifferentialpriortobursting.TheseresultsarealsoconservativeascomparedtoSt.LucieUnitl.Therefore,itcanbeconcludedthatPSL-1cancontinuetobesafelyoperatedduetothefollowing:1)TheIGA/SCCcanbedetectedandsizedthroughETmeans.Inaddition,theresultsofthehistoricaldatareviewdemonstratethattheattackhasoccurredearlyintheoperatinglifeoftheplant,andhasnotgrownsignificantlyduringthelatestcycle.ThatthecorrosionoccurredearlyintheoperatinglifeofSt.LucieUnit1isfurtherevidencedintheimprovementinsteamgeneratorwaterchemistrybeginningin1978.Furthermore,sincelate1982,theSt.LucieUnitshavebeenoperatingwithaverystringentsecondarywaterchemistrycontrolprogrambasedupontheEPRISteamGeneratorOwner'sGroup(SGOG)PWRSecondaryWaterChemistryGuidelines.Thisconclusioncanalsobesupportedbytheimprovementinsecondarywaterchemistrysincethe"adoptionofEPRIWaterChemistryGuidelines.2)BothFPLandindustrytestsdemonstratethatthroughwallcrackswillleakbeforebreak,andthatIGAaffectedtubeswillresistburstinguntilapressuremuchgreaterthanthePSLdesignbasisisreached.Therefore,apotentialproblemwillbedetectedpriortoitbecomingasafetyconcern,andthattheexistingconditionwillnotleadtoexceedingthedesignbasis.:cacMCI1:1 IIA 5/23/86PSL//11985R)STCUTIESTEAMCENERATCRMTAREVIBV"A"Gen.LineRow62829610612913715516286696977113960090110011070908502935657361515051610166595107065062921091091003238802580559Total13Total0 411v1lfI'J'(hl St.LucieUnit1EddCurrent-MetallorahCorrelationLocationSludgePile(120/12-2)1.3"ATSSludgePile(79/91-2)1.4"ATS4.4"ATStlEggCrate(59/95-4)02EggCrate(59/95-5)03EggCrate(120/12-7)FPLField41XUDS57%DSS29X82%Lab40X20X50%notseen25%80X8xl50%60X50%30X90XAr.tua10~eth30X16%42X52%13%72XOefect~AearaeceIG/TGSCCParallelA~i~I~~~~kslongestover1axiallengthacross360oftubecirc.0%ostover90IGAPATCH"axial"circ.1/2"xl/2naIGAPATCH"axial"circ..8"xl/2uaIGAPATCH(0.7axiax0.3circ.)IGAPATCH(04axiaIx0.3circ)IGA/TGSCCPARALLELaxialcracksinlanarea0.6"longestover2inchesaxialacross0.1"oftubecirc.
7.Unserviceable describes thecondition ofatubeifitIstructural integrity intheeventofanOperating BasisEarthquake, aloss-of-coolant
ATTACHMENT3NOSIGNIFICANTHAZARDSCONSIDERATIONDETERMINATIONThestandardsusedtoarriveatadeterminationthatarequestforamendmentinvolvesnosignificanthazardsconsiderationareincludedintheCommission'sregulations,10CFR50.92,whichstatesthatnosignificanthazardsconsiderationsareinvolvediftheoperationofthefacilityinaccordancewiththeproposedamendmentwouldnot(1)involveasignificantincreaseintheprobabilityorconsequencesofanaccidentpreviouslyevaluated;or(2)createthepossibilityofanewordifferentkindofaccidentfromanyaccidentpreviouslyevaluated;or(3)involveasignificantreductioninamarginofsafety.Eachstandardisdiscussedasfollows:(1)Operationofthefacilityinaccordancewiththeproposedamendmentwouldnotinvolveasignificantincreaseintheprobabilityorconsequencesofanaccidentpreviouslyevaluated.Theeventsofconcernforthisamendmentarethosewhichcouldpotentiallyleadtoasteamgeneratortuberuptureduringnormaloperationoraccidentconditions.RecentmetallurgicalanalysesoftubesamplesremovedfromaSt.LucieUnit1steamgeneratorduringthelate-1985refuelingoutageandanextensivereviewofeddy-currentdatafor100Foofthetubesinbothsteamgeneratorsindicatesthattheconditionofthetubeshasbeencharacterizedwithahighdegreeofconfidenceandthatthephenomenonofconcern(intergranularattack,orIGA)hasnotprogressedsignificantlyduringthelatestcycle.Furthermore,theeffectivetimeperiodoftheamendmentislimitedto30days.Thus,theuseofthemodifiedspecificationunderthesecircumstancesdoesnotinvolveasignificantincreaseintheprobabilityofoccurrenceofasteamgeneratortuberuptureeventoranyothereventpreviouslyevaluated.Inaddition,recentresultsofFPLandindustryleakratetestingindicatethatthrough-wallcrackswill"leakbeforebreak,"andthatIGA-affectedtubeswillmaintainintegritytoapressuregreaterthanthedesignbasispressureapplicableinthissituationtotheSt.LucieUnit1steamgenerators;therefore,theconsequencesofpreviouslyevaluatedaccidentsarenotsignificantlyincreasedbythisamendment.(2)Useofthemodifiedspecificationwouldnotcreatethepossibilityofanewordifferentkindofaccidentfromanyaccidentpreviouslyevaluated.TheevaluationperformedbyCE,ofsteamgeneratortubeswithgreaterdegradationthanthatpresentatPSL1,ensuresthatthismodificationwillnotcreatethepossibilityofanewordifferentkindofaccidentfromanyaccidentpreviouslyevaluated.  
: accident, orasteamlineorfeedwater linebreakasspecified in4.4.5.3.c, above,S.TubeInspection meansaninspection ofthesteamgenerator tubefromthepointofentry(hotlegside)completely aroundtheU-bendtothetopsupportofthecoldleg.b.Thesteamgenerator shallbedetermined OPERABLEaftercompleting thecorresponding actions(plugalltubesexceeding theplugginglimitandalltubescontaining through-wa11 cracks)requiredbyTable4.4-2.4.4.5.5Reportsa~Following eachinservice inspection ofsteamgenerator tubes,thenumberoftubespluggedineachsteamgenerator shallbereportedtotheCoomission within15days.b.Thecompleteresultsofthesteamgenerator tubeinservice inspection shallbeincludedintheAnnualOperating Reportfortheperiodinwhichthisinspection wascompleted.
'L4Vg,(~lK'laUIA 4~Q~~(3)Useofthemodifiedspecificationwouldnotinvolveasignificantreductioninamarginofsafety.Industry'datahasdemonstratedthattubematerialbelowtheareaofuniformlydegradedIGAremainssound,andtestshaveshownthattubeswithIGAwillsustain,differentialpressuressubstantiallygreaterthanthosepredictedduringdesignbasisaccidents.ThelimitingstressconditionfortubesarethoserequirementsofRegulatoryGuide1.121whichcallsfortubingtobeabletowithstandthreetimesnormaloperatingdifferentialpressurewithoutbursting.Sixteenoftheseventeendefectsmeetthisrequirement.Theseventeenthhasasafetyfactorofapproximately2.75.TestsspecifictoFPLhavebeenconductedtoverifythattheleak-before-breakconceptappliestotheSt.LucieUnit1steamgeneratorsandthatpotentialproblemswillbedetectedbeforetheybecomesignificantsafetyconcerns.Thus,useofthemodifiedspecification,especiallyoveralimited30-daytimeperiod,doesnotinvolveasignificantreductioninamarginofsafetyinthattheASMESectionIIICodelimits(NB-3225)arenotsurpassed,andthattherequirementsofRegulatoryGuide1.121aremetbyalldefectswiththeexceptionofonewhichhasaslightlyreducedmarginofsafety.Basedonourcompilationofareliableandconservativeeddy-currentdatabase,ourdeterminationthatIGAisprogressingataslowrateofgrowth,theapplicabilityoftheleak-before-breakconcept,andtheshort-terminterimnatureofthemodifiedspecification(asdescribedabove),wehavedeterminedthattheamendmentrequestdoesnot(1)involveasignificantincreaseintheprobabilityorconsequencesofanaccidentpreviouslyevaluated,(2)createtheprobabilityofanewordifferentkindofaccidentfromanyaccidentpreviouslyevaluated,or(3)involveasignificantreductioninamarginofsafety;andthereforedoesnotinvolveasignificanthazardsconsideration.  
Thisreportshallinclude:1.Numberandextentoftubesinspected.
2.Locationandpercentofwall-thickness penetration foreachindication ofanimperfection.
3.Identification oftubesplugged.ammo000338IPDR'ST.LUCIE-UNIT1860609022idp 8PDRADOCK0p3/44-8~Cyc/e>llmr~g~s/o~~;~,ovMud~~~//q<p/~c4d.J/cp<o4~v~"8'p'C<4d<<)
~uF.  
~~Attachment 2St.LucieUnit1DocketNos.50-335Emergency LicenseAmendment SteamGenerator PluinLimitSAFETYEVALUATION Threesteamgenerator tubeswereremovedfromtheAsteamgenerator ofSt.LucieUnit1(PSL-1)duringtheOctober-December 1985outage.ThesewerethensenttoBRWforexamination inordertobettercharacterize theeddycurrent(ET)indications notedduringthe1980and1985exams.Thesummaryofthelaboratory workanditscorrelation tothefieldETresultsareshownontheattachedtable.Thepresenceofgrainboundarydegradation intheformofintergrannular attack(IGA)withsomestresscorrosion cracking(SCC)causedareviewofallthe1985ETdata,andahistorical reviewofapopulation ofdefects,Distorted SupportSignals(DSS)andUndefined Signals(UDS)aswellas1980-1985 pluggedtubes.Additionally, asampleofgreaterthan50%ofdistorted signalswerecomparedtothe1980datatoassessgrowth.UsingtheBdcWresultsasanindicator theresultsofthe1985ETexamrevealedthepresenceofseventeen indications havingdepth,OOFo.
Theseindications hadtypically beenclassified aseitherDSSorUDS.Whiledirectcomparisons ofpreviousETdataaredifficultduetotheuseofdifferingequipment andtechniques, thefollowing conclusions canbereached:a)Thereisnosignificant changeinindication depthorsignalamplitude betweenthe1980and1985data.b)Indications canbeidentified incertaintubesasearlyas1981inthemajorityofcases.Asmallnumbercanbetrackedto1979.TheindustrydataonIGA/SCCdemonstrates thatthetubematerialbelowthesurfaceareaofuniformly degradedIGA/SCCremainssoundanddoesnotsufferfromincipient degradation inthegrainboundaries.
TestshaveshownthattubeswithIGAwillsustainpressuredifferentials substantially greaterthanpredicted duringtheworstcasedesignbasisaccident(MSLB)priortoburst.Testinghasalsoshownthatthroughwallcracksof1inchinlengthleakbeforebreak.InordertoverifytheindustryresultsforPSL-l,samplesoftubingwereobtainedfromCEforthepurposeofleakratetesting.ThetestsrunatChattanooga usedthru-wall cracksof3/8",15/16",andIYi"inlengthfortheleak-before-break test.Theresultsdemonstrate thattheleakageofthroughwallcracksofthesizeseenonPSL-1postMainSteamLineBreak(MSLB)are  
~CIlItI'C<<C,4'r,C.~4,,(.UIr~CI'lfCI<<W4"4I'4WI'<<'<<(('=lfn.wfl4aC('r,4c'((rg(<<"t'(I'W'r<<I<<fh,,If'"'I(~<<I*('<<(~X wellbelowthoseassumedintheSafetyEvaluation.
Theseresultsareconservative inthatthemaximumcracklengthseenatPSL-1isapproximatley
.6".InadditionbursttestsrunonCEtubingfor3"long,fullycircumferential IGAverifythatIGAat70Focouldwithstand overtwicetheMSLBpressuredifferential priortobursting.
Theseresultsarealsoconservative ascomparedtoSt.LucieUnitl.Therefore, itcanbeconcluded thatPSL-1cancontinuetobesafelyoperatedduetothefollowing:
1)TheIGA/SCCcanbedetectedandsizedthroughETmeans.Inaddition, theresultsofthehistorical datareviewdemonstrate thattheattackhasoccurredearlyintheoperating lifeoftheplant,andhasnotgrownsignificantly duringthelatestcycle.Thatthecorrosion occurredearlyintheoperating lifeofSt.LucieUnit1isfurtherevidenced intheimprovement insteamgenerator waterchemistry beginning in1978.Furthermore, sincelate1982,theSt.LucieUnitshavebeenoperating withaverystringent secondary waterchemistry controlprogrambasedupontheEPRISteamGenerator Owner'sGroup(SGOG)PWRSecondary WaterChemistry Guidelines.
Thisconclusion canalsobesupported bytheimprovement insecondary waterchemistry sincethe"adoption ofEPRIWaterChemistry Guidelines.
2)BothFPLandindustrytestsdemonstrate thatthroughwallcrackswillleakbeforebreak,andthatIGAaffectedtubeswillresistburstinguntilapressuremuchgreaterthanthePSLdesignbasisisreached.Therefore, apotential problemwillbedetectedpriortoitbecomingasafetyconcern,andthattheexistingcondition willnotleadtoexceeding thedesignbasis.:cacMCI1:1 IIA 5/23/86PSL//11985R)STCUTIESTEAMCENERATCR MTAREVIBV"A"Gen.LineRow62829610612913715516286696977113960090110011070908502935657361515051610166595107065062921091091003238802580559Total13Total0 411v1lfI'J'(hl St.LucieUnit1EddCurrent-MetallorahCorrelation LocationSludgePile(120/12-2) 1.3"ATSSludgePile(79/91-2) 1.4"ATS4.4"ATStlEggCrate(59/95-4)02EggCrate(59/95-5) 03EggCrate(120/12-7)
FPLField41XUDS57%DSS29X82%Lab40X20X50%notseen25%80X8xl50%60X50%30X90XAr.tua10~eth30X16%42X52%13%72XOefect~Aearaece IG/TGSCCParallelA~i~I~~~~kslongestover1axiallengthacross360oftubecirc.0%ostover90IGAPATCH"axial"circ.1/2"xl/2na IGAPATCH"axial"circ..8"xl/2ua IGAPATCH(0.7axiax0.3circ.)IGAPATCH(04axiaIx0.3circ)IGA/TGSCCPARALLELaxialcracksinlanarea0.6"longestover2inchesaxialacross0.1"oftubecirc.
ATTACHMENT 3NOSIGNIFICANT HAZARDSCONSIDERATION DETERMINATION Thestandards usedtoarriveatadetermination thatarequestforamendment involvesnosignificant hazardsconsideration areincludedintheCommission's regulations, 10CFR50.92,whichstatesthatnosignificant hazardsconsiderations areinvolvediftheoperation ofthefacilityinaccordance withtheproposedamendment wouldnot(1)involveasignificant increaseintheprobability orconsequences ofanaccidentpreviously evaluated; or(2)createthepossibility ofanewordifferent kindofaccidentfromanyaccidentpreviously evaluated; or(3)involveasignificant reduction inamarginofsafety.Eachstandardisdiscussed asfollows:(1)Operation ofthefacilityinaccordance withtheproposedamendment wouldnotinvolveasignificant increaseintheprobability orconsequences ofanaccidentpreviously evaluated.
Theeventsofconcernforthisamendment arethosewhichcouldpotentially leadtoasteamgenerator tuberuptureduringnormaloperation oraccidentconditions.
Recentmetallurgical analysesoftubesamplesremovedfromaSt.LucieUnit1steamgenerator duringthelate-1985 refueling outageandanextensive reviewofeddy-current datafor100Foofthetubesinbothsteamgenerators indicates thatthecondition ofthetubeshasbeencharacterized withahighdegreeofconfidence andthatthephenomenon ofconcern(intergranular attack,orIGA)hasnotprogressed significantly duringthelatestcycle.Furthermore, theeffective timeperiodoftheamendment islimitedto30days.Thus,theuseofthemodifiedspecification underthesecircumstances doesnotinvolveasignificant increaseintheprobability ofoccurrence ofasteamgenerator tuberuptureeventoranyothereventpreviously evaluated.
Inaddition, recentresultsofFPLandindustryleakratetestingindicatethatthrough-wall crackswill"leakbeforebreak,"andthatIGA-affected tubeswillmaintainintegrity toapressuregreaterthanthedesignbasispressureapplicable inthissituation totheSt.LucieUnit1steamgenerators; therefore, theconsequences ofpreviously evaluated accidents arenotsignificantly increased bythisamendment.
(2)Useofthemodifiedspecification wouldnotcreatethepossibility ofanewordifferent kindofaccidentfromanyaccidentpreviously evaluated.
Theevaluation performed byCE,ofsteamgenerator tubeswithgreaterdegradation thanthatpresentatPSL1,ensuresthatthismodification willnotcreatethepossibility ofanewordifferent kindofaccidentfromanyaccidentpreviously evaluated.  
'L4Vg,(~lK'laUIA 4~Q~~(3)Useofthemodifiedspecification wouldnotinvolveasignificant reduction inamarginofsafety.Industry'datahasdemonstrated thattubematerialbelowtheareaofuniformly degradedIGAremainssound,andtestshaveshownthattubeswithIGAwillsustain,differential pressures substantially greaterthanthosepredicted duringdesignbasisaccidents.
Thelimitingstresscondition fortubesarethoserequirements ofRegulatory Guide1.121whichcallsfortubingtobeabletowithstand threetimesnormaloperating differential pressurewithoutbursting.
Sixteenoftheseventeen defectsmeetthisrequirement.
Theseventeenth hasasafetyfactorofapproximately 2.75.TestsspecifictoFPLhavebeenconducted toverifythattheleak-before-breakconceptappliestotheSt.LucieUnit1steamgenerators andthatpotential problemswillbedetectedbeforetheybecomesignificant safetyconcerns.
Thus,useofthemodifiedspecification, especially overalimited30-daytimeperiod,doesnotinvolveasignificant reduction inamarginofsafetyinthattheASMESectionIIICodelimits(NB-3225) arenotsurpassed, andthattherequirements ofRegulatory Guide1.121aremetbyalldefectswiththeexception ofonewhichhasaslightlyreducedmarginofsafety.Basedonourcompilation ofareliableandconservative eddy-current database,ourdetermination thatIGAisprogressing ataslowrateofgrowth,theapplicability oftheleak-before-break concept,andtheshort-term interimnatureofthemodifiedspecification (asdescribed above),wehavedetermined thattheamendment requestdoesnot(1)involveasignificantincreaseintheprobability orconsequences ofanaccidentpreviously evaluated, (2)createtheprobability ofanewordifferent kindofaccidentfromanyaccidentpreviously evaluated, or(3)involveasignificant reduction inamarginofsafety;andtherefore doesnotinvolveasignificant hazardsconsideration.  
~/~~~\J4eI(~'AII}}
~/~~~\J4eI(~'AII}}

Revision as of 17:04, 29 June 2018

Proposed Changes to Tech Specs,Temporarily Modifying Plugging Limit Requirements to Permit Power Operation W/Some Steam Generator Tubes Exceeding Plugging Limits
ML17216A571
Person / Time
Site: Saint Lucie NextEra Energy icon.png
Issue date: 05/30/1986
From:
FLORIDA POWER & LIGHT CO.
To:
Shared Package
ML17216A569 List:
References
NUDOCS 8606090226
Download: ML17216A571 (12)
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Text

REACTORCOOLASYSTEMSURVEILLANCE REOUIRENENTS Continued 5.Oefectmeansanimperfection ofsuchseveritythatitexceedstheplugginglimit.Atubecontaining adefectisdefective.

Anytubewhichdoesnotpermitthepassageoftheeddy-current inspection probeshallbedeemedadefective tube.L.whichthetubeshallberemovedfromservicebecauseitmaybecomeunserviceable priortothenextinspection andisequalto40&fthenominaltubewallthickness.

7.Unserviceable describes thecondition ofatubeifitIstructural integrity intheeventofanOperating BasisEarthquake, aloss-of-coolant

accident, orasteamlineorfeedwater linebreakasspecified in4.4.5.3.c, above,S.TubeInspection meansaninspection ofthesteamgenerator tubefromthepointofentry(hotlegside)completely aroundtheU-bendtothetopsupportofthecoldleg.b.Thesteamgenerator shallbedetermined OPERABLEaftercompleting thecorresponding actions(plugalltubesexceeding theplugginglimitandalltubescontaining through-wa11 cracks)requiredbyTable4.4-2.4.4.5.5Reportsa~Following eachinservice inspection ofsteamgenerator tubes,thenumberoftubespluggedineachsteamgenerator shallbereportedtotheCoomission within15days.b.Thecompleteresultsofthesteamgenerator tubeinservice inspection shallbeincludedintheAnnualOperating Reportfortheperiodinwhichthisinspection wascompleted.

Thisreportshallinclude:1.Numberandextentoftubesinspected.

2.Locationandpercentofwall-thickness penetration foreachindication ofanimperfection.

3.Identification oftubesplugged.ammo000338IPDR'ST.LUCIE-UNIT1860609022idp 8PDRADOCK0p3/44-8~Cyc/e>llmr~g~s/o~~;~,ovMud~~~//q<p/~c4d.J/cp<o4~v~"8'p'C<4d<<)

~uF.

~~Attachment 2St.LucieUnit1DocketNos.50-335Emergency LicenseAmendment SteamGenerator PluinLimitSAFETYEVALUATION Threesteamgenerator tubeswereremovedfromtheAsteamgenerator ofSt.LucieUnit1(PSL-1)duringtheOctober-December 1985outage.ThesewerethensenttoBRWforexamination inordertobettercharacterize theeddycurrent(ET)indications notedduringthe1980and1985exams.Thesummaryofthelaboratory workanditscorrelation tothefieldETresultsareshownontheattachedtable.Thepresenceofgrainboundarydegradation intheformofintergrannular attack(IGA)withsomestresscorrosion cracking(SCC)causedareviewofallthe1985ETdata,andahistorical reviewofapopulation ofdefects,Distorted SupportSignals(DSS)andUndefined Signals(UDS)aswellas1980-1985 pluggedtubes.Additionally, asampleofgreaterthan50%ofdistorted signalswerecomparedtothe1980datatoassessgrowth.UsingtheBdcWresultsasanindicator theresultsofthe1985ETexamrevealedthepresenceofseventeen indications havingdepth,OOFo.

Theseindications hadtypically beenclassified aseitherDSSorUDS.Whiledirectcomparisons ofpreviousETdataaredifficultduetotheuseofdifferingequipment andtechniques, thefollowing conclusions canbereached:a)Thereisnosignificant changeinindication depthorsignalamplitude betweenthe1980and1985data.b)Indications canbeidentified incertaintubesasearlyas1981inthemajorityofcases.Asmallnumbercanbetrackedto1979.TheindustrydataonIGA/SCCdemonstrates thatthetubematerialbelowthesurfaceareaofuniformly degradedIGA/SCCremainssoundanddoesnotsufferfromincipient degradation inthegrainboundaries.

TestshaveshownthattubeswithIGAwillsustainpressuredifferentials substantially greaterthanpredicted duringtheworstcasedesignbasisaccident(MSLB)priortoburst.Testinghasalsoshownthatthroughwallcracksof1inchinlengthleakbeforebreak.InordertoverifytheindustryresultsforPSL-l,samplesoftubingwereobtainedfromCEforthepurposeofleakratetesting.ThetestsrunatChattanooga usedthru-wall cracksof3/8",15/16",andIYi"inlengthfortheleak-before-break test.Theresultsdemonstrate thattheleakageofthroughwallcracksofthesizeseenonPSL-1postMainSteamLineBreak(MSLB)are

~CIlItI'C<<C,4'r,C.~4,,(.UIr~CI'lfCI<<W4"4I'4WI'<<'<<(('=lfn.wfl4aC('r,4c'((rg(<<"t'(I'W'r<<I<<fh,,If'"'I(~<<I*('<<(~X wellbelowthoseassumedintheSafetyEvaluation.

Theseresultsareconservative inthatthemaximumcracklengthseenatPSL-1isapproximatley

.6".InadditionbursttestsrunonCEtubingfor3"long,fullycircumferential IGAverifythatIGAat70Focouldwithstand overtwicetheMSLBpressuredifferential priortobursting.

Theseresultsarealsoconservative ascomparedtoSt.LucieUnitl.Therefore, itcanbeconcluded thatPSL-1cancontinuetobesafelyoperatedduetothefollowing:

1)TheIGA/SCCcanbedetectedandsizedthroughETmeans.Inaddition, theresultsofthehistorical datareviewdemonstrate thattheattackhasoccurredearlyintheoperating lifeoftheplant,andhasnotgrownsignificantly duringthelatestcycle.Thatthecorrosion occurredearlyintheoperating lifeofSt.LucieUnit1isfurtherevidenced intheimprovement insteamgenerator waterchemistry beginning in1978.Furthermore, sincelate1982,theSt.LucieUnitshavebeenoperating withaverystringent secondary waterchemistry controlprogrambasedupontheEPRISteamGenerator Owner'sGroup(SGOG)PWRSecondary WaterChemistry Guidelines.

Thisconclusion canalsobesupported bytheimprovement insecondary waterchemistry sincethe"adoption ofEPRIWaterChemistry Guidelines.

2)BothFPLandindustrytestsdemonstrate thatthroughwallcrackswillleakbeforebreak,andthatIGAaffectedtubeswillresistburstinguntilapressuremuchgreaterthanthePSLdesignbasisisreached.Therefore, apotential problemwillbedetectedpriortoitbecomingasafetyconcern,andthattheexistingcondition willnotleadtoexceeding thedesignbasis.:cacMCI1:1 IIA 5/23/86PSL//11985R)STCUTIESTEAMCENERATCR MTAREVIBV"A"Gen.LineRow62829610612913715516286696977113960090110011070908502935657361515051610166595107065062921091091003238802580559Total13Total0 411v1lfI'J'(hl St.LucieUnit1EddCurrent-MetallorahCorrelation LocationSludgePile(120/12-2) 1.3"ATSSludgePile(79/91-2) 1.4"ATS4.4"ATStlEggCrate(59/95-4)02EggCrate(59/95-5) 03EggCrate(120/12-7)

FPLField41XUDS57%DSS29X82%Lab40X20X50%notseen25%80X8xl50%60X50%30X90XAr.tua10~eth30X16%42X52%13%72XOefect~Aearaece IG/TGSCCParallelA~i~I~~~~kslongestover1axiallengthacross360oftubecirc.0%ostover90IGAPATCH"axial"circ.1/2"xl/2na IGAPATCH"axial"circ..8"xl/2ua IGAPATCH(0.7axiax0.3circ.)IGAPATCH(04axiaIx0.3circ)IGA/TGSCCPARALLELaxialcracksinlanarea0.6"longestover2inchesaxialacross0.1"oftubecirc.

ATTACHMENT 3NOSIGNIFICANT HAZARDSCONSIDERATION DETERMINATION Thestandards usedtoarriveatadetermination thatarequestforamendment involvesnosignificant hazardsconsideration areincludedintheCommission's regulations, 10CFR50.92,whichstatesthatnosignificant hazardsconsiderations areinvolvediftheoperation ofthefacilityinaccordance withtheproposedamendment wouldnot(1)involveasignificant increaseintheprobability orconsequences ofanaccidentpreviously evaluated; or(2)createthepossibility ofanewordifferent kindofaccidentfromanyaccidentpreviously evaluated; or(3)involveasignificant reduction inamarginofsafety.Eachstandardisdiscussed asfollows:(1)Operation ofthefacilityinaccordance withtheproposedamendment wouldnotinvolveasignificant increaseintheprobability orconsequences ofanaccidentpreviously evaluated.

Theeventsofconcernforthisamendment arethosewhichcouldpotentially leadtoasteamgenerator tuberuptureduringnormaloperation oraccidentconditions.

Recentmetallurgical analysesoftubesamplesremovedfromaSt.LucieUnit1steamgenerator duringthelate-1985 refueling outageandanextensive reviewofeddy-current datafor100Foofthetubesinbothsteamgenerators indicates thatthecondition ofthetubeshasbeencharacterized withahighdegreeofconfidence andthatthephenomenon ofconcern(intergranular attack,orIGA)hasnotprogressed significantly duringthelatestcycle.Furthermore, theeffective timeperiodoftheamendment islimitedto30days.Thus,theuseofthemodifiedspecification underthesecircumstances doesnotinvolveasignificant increaseintheprobability ofoccurrence ofasteamgenerator tuberuptureeventoranyothereventpreviously evaluated.

Inaddition, recentresultsofFPLandindustryleakratetestingindicatethatthrough-wall crackswill"leakbeforebreak,"andthatIGA-affected tubeswillmaintainintegrity toapressuregreaterthanthedesignbasispressureapplicable inthissituation totheSt.LucieUnit1steamgenerators; therefore, theconsequences ofpreviously evaluated accidents arenotsignificantly increased bythisamendment.

(2)Useofthemodifiedspecification wouldnotcreatethepossibility ofanewordifferent kindofaccidentfromanyaccidentpreviously evaluated.

Theevaluation performed byCE,ofsteamgenerator tubeswithgreaterdegradation thanthatpresentatPSL1,ensuresthatthismodification willnotcreatethepossibility ofanewordifferent kindofaccidentfromanyaccidentpreviously evaluated.

'L4Vg,(~lK'laUIA 4~Q~~(3)Useofthemodifiedspecification wouldnotinvolveasignificant reduction inamarginofsafety.Industry'datahasdemonstrated thattubematerialbelowtheareaofuniformly degradedIGAremainssound,andtestshaveshownthattubeswithIGAwillsustain,differential pressures substantially greaterthanthosepredicted duringdesignbasisaccidents.

Thelimitingstresscondition fortubesarethoserequirements ofRegulatory Guide1.121whichcallsfortubingtobeabletowithstand threetimesnormaloperating differential pressurewithoutbursting.

Sixteenoftheseventeen defectsmeetthisrequirement.

Theseventeenth hasasafetyfactorofapproximately 2.75.TestsspecifictoFPLhavebeenconducted toverifythattheleak-before-breakconceptappliestotheSt.LucieUnit1steamgenerators andthatpotential problemswillbedetectedbeforetheybecomesignificant safetyconcerns.

Thus,useofthemodifiedspecification, especially overalimited30-daytimeperiod,doesnotinvolveasignificant reduction inamarginofsafetyinthattheASMESectionIIICodelimits(NB-3225) arenotsurpassed, andthattherequirements ofRegulatory Guide1.121aremetbyalldefectswiththeexception ofonewhichhasaslightlyreducedmarginofsafety.Basedonourcompilation ofareliableandconservative eddy-current database,ourdetermination thatIGAisprogressing ataslowrateofgrowth,theapplicability oftheleak-before-break concept,andtheshort-term interimnatureofthemodifiedspecification (asdescribed above),wehavedetermined thattheamendment requestdoesnot(1)involveasignificantincreaseintheprobability orconsequences ofanaccidentpreviously evaluated, (2)createtheprobability ofanewordifferent kindofaccidentfromanyaccidentpreviously evaluated, or(3)involveasignificant reduction inamarginofsafety;andtherefore doesnotinvolveasignificant hazardsconsideration.

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