ML17228B368

From kanterella
Revision as of 15:53, 29 June 2018 by StriderTol (talk | contribs) (Created page by program invented by StriderTol)
Jump to navigation Jump to search
Responds to Violations Noted in Insp Repts 50-335/95-20 & 50-389/95-20.Corrective Actions:Multidiscipline Team Established to Perform Comprehensive Review of Nuclear safety-related Relief Valve Lift & Blowdown Settings
ML17228B368
Person / Time
Site: Saint Lucie  NextEra Energy icon.png
Issue date: 12/19/1995
From: GOLDBERG J H
FLORIDA POWER & LIGHT CO.
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
L-95-333, NUDOCS 9512260055
Download: ML17228B368 (7)


See also: IR 05000335/1995020

Text

LXAMAXEA(ACCELERATED

RIDSPROCESSIiC

REGULATORY

INFORMATION

DISTRIBUTION

SYSTEM(RIDS)CESSIONNBR:9512260055

DOC.DATE:95/12/19NOTARIZED:

NOFACIL:50-335

St.LuciePlant,Unit1,FloridaPower&LightCo.50-389St.LuciePlant,Unit2,FloridaPower&LightCo.AUTH.NAMEAUTHORAFFILIATION

GOLDBERG,J.H.

FloridaPower&LightCo.RECIP.NAME

RECIPIENT

AFFILIATION

DocumentControlBranch(Document

ControlDesk)SUBJECT:Respondstoviolations

notedininsprepts50-335/95-20

50-389/95-20.Corrective

actions:multidiscipline

teamestablished

toperformcomprehensive

reviewofnuclearsafety-related

reliefvalvelift&blowdownsettings.

DISTRIEDTION

CODE:IEOIDCOPIESRECEIVED:LTR

IENCLgSIZE:TITLE:General(50Dkt)-InspRept/Notice

ofVioTation

ResponseNOTES:DOCKET0500033505000389RECIPIENT

IDCODE/NAME

PD2-1PDINTERNAL:

ACRSAEOD/SPD/RAB

DEDRONRR/DISP/PIPB

NRR/DRPM/PECB

NUDOCS-ABSTRACT

OGC/HDS3EXTERNAL:

LITCOBRYCE,JH'RCPDRCOPIESLTTRENCL11221111111111111111RECIPIENT

IDCODE/NAME

NORRIS,JAEOD/DEIB

AEOTCLECERNCTP/HHFBNRR/DRPM/PERB

OEDIRRGN2FILE01NOACCOPIESLTTRENCL111111111111111111VOTETOALL"RIDS"RECIPIEY'TS:PLEASEHELPUSTOREDUCEiVASTE!COYTACTTHE

DOCL'ifEYT

COYTROLDESK.ROOMPl-37(EXT.504.2083)TOELIXIIiATE5'OI.'RiAiIEFROilDISTRIBUTIOY

LISTSI'ORDOCI.'MEi'I'S

YOUDOi"I'ELIDIOTALNUMBEROFCOPIESREQUIRED:

LTTR20ENCL20

FloridaPower5LightCompany,P.O.Box128,FortPierce,FL34954-0128

FPLDEC191995L-95-33310CFR2.201U.S.NuclearRegulatory

Commission

Attn:DocumentControlDeskWashington,

D.'.20555Re:St.LucieUnits1and2DocketNo.50-335and50-389ReplytoNoticeofViolation

IninR-2-EA-222FloridaPowerandLightCompany(FPL)hasreviewedthesubject,noticeofviolation

issuedonNovember28,1995.Pursuantto10CFR2.201,theresponseisattached.

OnDecember1,1995,theNRCseniorresidentinspector

forSt.LucienotifiedFPLthattheresponsetothisnoticeofviolation

wasnotrequiredtobesubmitted

underoathoraffirmation

asoriginally

requested

'bythenoticeofviolation.

Verytrulyyours,J.H.oldbergPresident

-NuclearDivisionJHG/GRMAttachment

cc:StewartD.Ebneter,RegionalAdministrator,

USNRCRegionIISeniorResidentInspector,

USNRC,St.LuciePlantQf>P;~rVit~r9512260055

951219PDRADDCK050003359PDRanFPLGroupcompany

Re:St.LucieUnits1and2DocketNo.50-335and50-389ReplytoNoticeofViolation

InsecinRe-20Violation

EA5-22210CFR50,AppendixB,Criterion

XVI,"Corrective

Actions,"

requires,

inpart,thatmeasuresbeestablished

toassurethatconditions

adversetoqualityarepromptlyidentified

andcorrected.

Contrarytotheabove,conditions

adversetoquality,involving

reliefvalvesetpointandblowdownvalues,identified

onFebruary20,March2,andMarch10,1995,didnotreceivepromptcorrective

actionsandledtoarepeatofpreviously

identified

problemsonAugust10,1995,whenUnit1reliefvalveV-3439liftedandfailedtoreseatwithoutoperatorintervention.

Thesubjecteventresultedinapproximately

4000gallonsofreactorcoolantaccumulating

intheUnit1pipetunnel.Evaluations

performed

afterthiseventrevealedtheneedtoreplace,orestablish

newsetpoints

for,severalreliefvalvesinsafetysystemsinbothunits.ThisisaSeverityLevelIVviolation

(Supplement

I).FPLRne1.Thereasonfortheviolation:

Theseriesofreliefvalveeventsthatoccurredinearly1995tookplaceindifferent

plantsystemsandinvolvedbothSt.LucieUnit1andUnit2.Initialplanteffortstocorrecttheseindividual

planteventswerefocusedonsolvingtheplantsystemcontrolproblemsthatledtothepressuretransients

causingtheseriesofreliefvalveactuation.

Briefly,theseeventsarediscussed

below:ThecausesoftheUnit1andUnit2letdownevents(betweenJanuary23,1995andJuly8,1995)wereassociated

withletdownpressurecontrolproblems.

Thecorrective

actionswerefocusedontheletdownpressurecontrolvalveperformance.

ThecauseoftheUnit2component

coolingwaterreliefvalveactuation

event(February

17,1995)wasatestconfiguration

problem.AtthetimeoftheNRCinspection

forthesubjectinspection

report,asystemtransient

testwasbeingdeveloped

toevaluatetheconfiguration

problem.

l

ThecauseoftheUnit1shutdowncoolingsuctionreliefevent(February

27,1995)wasaflowinitiated

pressuretransient.

Thecorrective

actionwastheimplementation

ofaprocedure

changewhichmitigates

thepotential

forpressuretransients

whileplacingshutdowncoolinginservice.Longtermcorrective

actionsarediscussed

inparagraph

2.D.ThecauseoftheUnit1shutdowncoolingdischarge

relief(V3439)event(August10,1995)wasidentified

asadesignliftandblowdownsetpointproblem.Oncetherelieflifted,itdidnotreseatwithoutoperatorintervention

toisolatetheaffectedportionofthesystem.Thecorrective

actionsweretoreplacethevalveV3439andtoincreasethereliefvalveliftsetpointandtoreducetheblowdownsettingtherebyproviding

additional

operating

margin.Theseindividual

eventsdidnotappeartoshareacommonrootcauseandcorrective

actionstoresolvetheseindividual

problemswerepromptlyinitiated

byplantmanagement.

Agenericreliefvalvesetpointconcernwasidentified

bytheOperations

Supervisor

onMarch2,1995(following

theFebruary27,1995event),andwasassignedtoMechanical

Maintenance

forresolution.

BetweenMarchandAugustof1995,Maintenance

focusedondeveloping

threecorrective

actions:1)anewreliefvalvetestbench,2)revisions

tovalvetestprocedures,

and3)improvedmaintenance

training.

Maintenance

hadnotconsidered

adesignproblemwithreliefvalvesetpoints

and,therefore,

effortsweredirectedtowardverifying

thatthereliefvalvescouldbesetinaccordance

withplantdesign.Theunderlying

rootcausefortheseriesofreliefvalveevents-lackofdesignintegration

betweensystemoperating

pressures

andreliefvalvereseatpressures

-wasnotevidentuntiltheSt.LucieUnit1shutdowncoolingdischarge

reliefevent(August10,1995).Atthattime,theEngineering

Department

established

amulti-disciplined

teamtoinvestigate

safety-related

reliefvalveliftandreseatsettings.

TheSt.LucieActionRequest(STAR)processwasacontributing

factortothedelayinfindingtheunderlying

rootcauseoftheevents.TheSTARprocessreliedonseriesassignments

foractionsanddidnotlenditselftoparallelinvestigations

orcorrective

actions.Thecorrective

stepsthathaveorwillbetakenandtheresultsachieved:

A.Thecorrective

actionstakentoaddressthespecificproblemofsafetyrelatedreliefvalveliftandblowdownsettingsandcontrolofreliefvalvedesigninformation

wereprovidedintheUnit1LicenseeEventReport(LED)95-06,andatthepre-decisional

enforcement

conference

onNovember14,1995.

B.InAugust1995,amulti-discipline

teamwasestablished

toperformacomprehensive

reviewoftheSt.LucieUnit1andUnit2nuclearsafetyrelatedreliefvalveliftandblowdownsettings.

Theteamwascomposedofpersonnel

fromMaintenance,

Operations,

PlantSystemEcComponent

Engineering,

andNuclearEngineering.

Atotalof114reliefvalveswerereviewed(53forUnit1and61forUnit2)andtheirdesignsettingswereevaluated

relativetosystemoperating

andtransient

pressures.

Seventeen

ofthesevalvesrequiredadditional

analysis.

Corrective

actions,exceptasnotedin2.Dbelow,havebeentakentoincreasethemarginbetweensystemoperating

pressures

andthelift/reseat

setting,whereappropriate.

C.Unit1reliefvalvemodifications,

withtheexception

oftheshutdowncoolingsuctionoverpressure

reliefvalves,V3468andV3483,wereimplemented

priortotheOctober1995startup,following

theshutdownrelatedtoHurricane

Erin.D.Unit1shutdowncoolingsuctionoverpressure

reliefvalves,V3468andV3483,liftsettingswereadjustedtoimprovetheliftmarginpriortotheOctober1995startup.Withtheserevisedliftsettings,

shutdowncoolingcanbeinitiated

withoutchallenging

thesereliefvalves.TheliftandblowdownsettingswillbefurthermodifiedduringtheSpring1996refueling

outage.E.Unit2reliefvalvemodifications

wereimplemented

duringtheFall1995refueling

outage.3.Thecorrective

stepstakenorplannedtoavoidfurtherviolations:

~A.FPLMaintenance

Specification

SPEC-M-038,

SafetyRelatedReliefValveSetpoints

St.LucieUnits1and2,wasissuedinNovember1995toinstitutionalize

theresultsofthereliefvalvedesignreviewteam.B.TheSTARprocesswasmodifiedtofacilitate

paralleldepartment

assignments

fortheevaluation

andcorrection

ofdeficiencies.

4.Thedatewhenfullcompliance

willbeachieved:

A.TheSTARprocessprocedure

wasmodifiedinOctober1995.B.Fullcompliance

forthereliefvalvesettingswillbeachievedduringtheSpring1996refueling

outage.