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| {{#Wiki_filter:CATEGORY1~REGULARLY INFORMATION DISTRIBUTIOF%YSTEM (RIDS)p)*ACCESSION NBR:9802110012 DOC.DATE: | | {{#Wiki_filter:CATEGORY 1~REGULARLY INFORMATION DISTRIBUTIOF%YSTEM (RIDS)p)*ACCESSION NBR:9802110012 DOC.DATE: 98/02/03 NOTARIZED: |
| 98/02/03NOTARIZED: | | NO FACIL:50-335 St.Lucie Plant, Unit 1, Florida Power&Light Co.AUTH.NAME AUTHOR AFFILIATION FREiIXFER,K.W. |
| NOFACIL:50-335 St.LuciePlant,Unit1,FloridaPower&LightCo.AUTH.NAMEAUTHORAFFILIATION FREiIXFER,K.W.
| | Florida Power&Light Co.-STALL,J.A. |
| FloridaPower&LightCo.-STALL,J.A.
| | Florida Power&Light Co.RECIP.NAME RECIPIENT AFFILIATION DOCKET¹05000335 |
| FloridaPower&LightCo.RECIP.NAME RECIPIENT AFFILIATION DOCKET¹05000335
| |
|
| |
|
| ==SUBJECT:== | | ==SUBJECT:== |
| LER98-001-00:on 980104,inadvertent RPSactuation occurredduetopersonnel error.Causedbyprocedural inadequacies
| | LER 98-001-00:on 980104,inadvertent RPS actuation occurred due to personnel error.Caused by procedural inadequacies |
| &,inadequate self-checking by.licensedutilitypersonnel. | | &, inadequate self-checking by.licensed utility personnel. |
| PlacardshavebeenplacedinCRs.W/980203 ltr.DISTRIBUTION CODE:IE22TCOPIESRECEIVED:LTR ENCLSIZE:TITLE:50.73/50.9 LicenseeEventReport(LER),IncidentRpt,etc.NOTES:'CRECIPIENT IDCODE/NAME PD2-3PDINTERNAL:
| | Placards have been placed in CRs.W/980203 ltr.DISTRIBUTION CODE: IE22T COPIES RECEIVED:LTR ENCL SIZE: TITLE: 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc.NOTES: 'C RECIPIENT ID CODE/NAME PD2-3 PD INTERNAL: ACRS AEOD/S PD/RRAB NRR/DE/ECGB NRR/DE/EMEB NRR/DRCH/HICB NRR/DRCH/HQMB NRR/DSSA/SPLB RES/DET/EIB EXTERNAL: L ST LOBBY WARD NOAC POORE,W.NRC PDR COPIES LTTR ENCL 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 RECIPIENT ID CODE/NAME WIENS,L.Cg NRR DE EELB NRR/DRCH/HHFB NRR/DRCH/HOLB NRR/DRPM/PECB NRR/DSSA/SRXB RGN2 FILE Ol LITCO BRYCE,J H NOAC QUEENER,DS NUDOCS FULL TXT COPIES LTTR ENCL 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 NOTE TO ALL"RIDS" RECIPIENTS: |
| ACRSAEOD/SPD/RRABNRR/DE/ECGB NRR/DE/EMEB NRR/DRCH/HICB NRR/DRCH/HQMB NRR/DSSA/SPLB RES/DET/EIB EXTERNAL:
| | PLEASE HELP US TO REDUCE WASTE.TO HAVE YOUR NAME OR ORGANIZATION REMOVED FROM DISTRIBUTION LIST>>OR REDUCE THE NUMBER OF COPIES RECEIVED BY YOU OR YOUR ORGANIZATION, CONTACT THE DOCUMENT CONTROI DESK (DCD)ON EXTENSION 415-2083 FULL TEXT CONVERSION REQUIRED TOTAL NUMBER OF COPIES REQUIRED: LTTR 25 ENCL 25 Florida Power&Light Company, 6351 S.Ocean Drive, Jensen Beach, FL 34957 February 3, 1998 L-98-018 10 CFR 50.73 U.S.Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C.20555 Re: St.Lucie Unit 1 Docket No.50-335 Reportable Event: 98-001 Date of Event: January 4, 1998 Inadvertent RPS Actuation Due to Personnel Error The attached Licensee Event Report is being submitted pursuant to the requirements of 10 CFR 50.73.Very truly yours, J.A.Stall Vice President St.Lucie Plant JAS/KWF Attachment cc: Regional Administrator, USNRC, Region II Senior Resident Inspector, USNRC, St.Lucie Plant'ir802ii0012 |
| LSTLOBBYWARDNOACPOORE,W.NRCPDRCOPIESLTTRENCL111111111111111111111111RECIPIENT IDCODE/NAME WIENS,L.CgNRRDEEELBNRR/DRCH/HHFB NRR/DRCH/HOLB NRR/DRPM/PECB NRR/DSSA/SRXB RGN2FILEOlLITCOBRYCE,JHNOACQUEENER,DS NUDOCSFULLTXTCOPIESLTTRENCL112211111111111111111111NOTETOALL"RIDS"RECIPIENTS:
| | 'rr80203 PDR ADQCK 05000335 8 PDR llllllllllllllllllllllllll llllllllllll an FPL Group company NRC FORM 366 (4.9e)U.S.NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)(See reverse for required number of digits/characters for each biock)APPROVED SV OMB No.S(60<0(O4 EXARES 04/30/S S ESTIMATED BURDEN PER RESPONSE TO COMPLY WITH THIS MANDATOR INFORMATION COLLECTION REOUEST: 60.0 HRS.REPORTED LESSON LEARNED ARE INCORPORATED INTO THE UCENSING PROCESS AND FE BACK TO INDUSTRY.FORWARD COMMENTS REGARDING BURDEN ESTIMAT TO THE INFORMATION AND RECORDS MANAGEMENT BRANCH (TW F33(US.NUCLEAR REGIAATORY COMMISSION, WASHINGTON, DC 20666ENO I AND TO THE PAPERWORK REDUCTION PROJECT (3(600104I, OFRCE 0 MANAGEMENT AND BUDGET, WASHINGTON, DC 20603.FACIUTY NAME UI ST LUCIE UNIT 1 TITLE (4I Inadvertent RPS Actuation Due to Personnel Error DOCKET NINVIB(R (2(05000335 PAGE (SI 1 OF4 DAY YEAR 4 98 YEAR SEOUENTIAL REVISION MONTH NUMBER NUMBER 98,-001-0 OAY YEAR 3 98 FACIUTY NAME FACIUTY NAME DOCKET NUMBER 05000 DOCKETNUMBER 05000 OPERATINQ MODE (9)POWER LEVEL l10)20.2201 (b)20.2203 (a)(2)6)20.2203{a) |
| PLEASEHELPUSTOREDUCEWASTE.TOHAVEYOURNAMEORORGANIZATION REMOVEDFROMDISTRIBUTION LIST>>ORREDUCETHENUMBEROFCOPIESRECEIVEDBYYOUORYOURORGANIZATION, CONTACTTHEDOCUMENTCONTROIDESK(DCD)ONEXTENSION 415-2083FULLTEXTCONVERSION REQUIREDTOTALNUMBEROFCOPIESREQUIRED:
| | (2)(iii)20.2203 (a)(2)(iv)20.2203(a) l2)(v)20.2203(a) |
| LTTR25ENCL25 FloridaPower&LightCompany,6351S.OceanDrive,JensenBeach,FL34957February3,1998L-98-01810CFR50.73U.S.NuclearRegulatory Commission Attn:DocumentControlDeskWashington, D.C.20555Re:St.LucieUnit1DocketNo.50-335Reportable Event:98-001DateofEvent:January4,1998Inadvertent RPSActuation DuetoPersonnel ErrorTheattachedLicenseeEventReportisbeingsubmitted pursuanttotherequirements of10CFR50.73.Verytrulyyours,J.A.StallVicePresident St.LuciePlantJAS/KWFAttachment cc:RegionalAdministrator, USNRC,RegionIISeniorResidentInspector, USNRC,St.LuciePlant'ir802ii0012
| | (3)(ii)50.36(c)(1)50.36(c)(2)50.73(a)l2){i)50.73(a)(2)(iii)50.73(a){2){v)50.73(a)(2)(vii) 50.73{0)l2)(viii)73.71 OTHER Specify In Abstract below or in NRC Form 366A NAME K.W.Frehafer, Licensing Engineer TELEPHONE NUMBER Src(vde Arta Codel (561)468-4284 CAUSE SYSTEM COMPONENT MANUFACTURER REPORTABLE TO NPRDS CAUSE SYSTEM COMPONENT MANUFACTURER To NPRDS JC N/A N/A N/A YES{It yes, complete EXPECTED SUBMISSION DATE).X No EXPECTED SUBMISSION DATE (15)MONTH OAY YEAR ABSTRACT (Umit to 1400 spaces, l.e., approximately 15 single-spaced tYpewritten lines)(16)On January 4, 1998, Unit 1 was at zero percent power, in Mode 3, with pressurizer pressure less than 1750 psig.A reactor plant heatup to normal operating temperature and pressure following refueling was in progress.The reactor trip breakers were closed and all reactor control element assemblies were fully inserted.The operators were directed to remove the zero power mode bypass keys for each channel of the reactor protection system once the fourth reactor coolant pump was started.The reactor trip breakers opened immediately after the reactor protection system'C'hannel zero power mode bypass was unbypassed. |
| 'rr80203PDRADQCK050003358PDRllllllllllllllllllllllllll llllllllllll anFPLGroupcompany NRCFORM366(4.9e)U.S.NUCLEARREGULATORY COMMISSION LICENSEEEVENTREPORT(LER)(Seereverseforrequirednumberofdigits/characters foreachbiock)APPROVEDSVOMBNo.S(60<0(O4 EXARES04/30/SSESTIMATED BURDENPERRESPONSETOCOMPLYWITHTHISMANDATORINFORMATION COLLECTION REOUEST:60.0HRS.REPORTEDLESSONLEARNEDAREINCORPORATED INTOTHEUCENSINGPROCESSANDFEBACKTOINDUSTRY. | | This event was caused by procedural inadequacies and inadequate self-checking by licensed utility personnel. |
| FORWARDCOMMENTSREGARDING BURDENESTIMATTOTHEINFORMATION ANDRECORDSMANAGEMENT BRANCH(TWF33(US.NUCLEARREGIAATORY COMMISSION, WASHINGTON, DC20666ENOIANDTOTHEPAPERWORK REDUCTION PROJECT(3(600104I, OFRCE0MANAGEMENT ANDBUDGET,WASHINGTON, DC20603.FACIUTYNAMEUISTLUCIEUNIT1TITLE(4IInadvertent RPSActuation DuetoPersonnel ErrorDOCKETNINVIB(R(2(05000335PAGE(SI1OF4DAYYEAR498YEARSEOUENTIAL REVISIONMONTHNUMBERNUMBER98,-001-0OAYYEAR398FACIUTYNAMEFACIUTYNAMEDOCKETNUMBER05000DOCKETNUMBER 05000OPERATINQ MODE(9)POWERLEVELl10)20.2201(b)20.2203(a)(2)6)20.2203{a)
| | The procedure did not address plant conditions necessary to ensure the reactor protection system thermal marginflow pressure trip setpoint was below actual system pressure when the zero power mode bypass keys were operated.During the event, plant conditions would have set the thermal margin/low pressure trip setpoint at 1887 psia, and actual reactor coolant system pressure was approximately 1740 psia when the reactor protection system zero power mode bypass was unbypassed. |
| (2)(iii)20.2203(a)(2)(iv)20.2203(a) l2)(v)20.2203(a) | | Additionally, the operator continued with the unbypassing of the zero power mode bypass and did not give the crew time to review the validity of the alarms and ensure all conditions were satisfactory prior to completing the procedure. |
| (3)(ii)50.36(c)(1)50.36(c)(2)50.73(a)l2){i)50.73(a)(2)(iii)50.73(a){2){v)50.73(a)(2)(vii) 50.73{0)l2)(viii)73.71OTHERSpecifyInAbstractbeloworinNRCForm366ANAMEK.W.Frehafer, Licensing EngineerTELEPHONE NUMBERSrc(vdeArtaCodel(561)468-4284CAUSESYSTEMCOMPONENT MANUFACTURER REPORTABLE TONPRDSCAUSESYSTEMCOMPONENT MANUFACTURER ToNPRDSJCN/AN/AN/AYES{Ityes,completeEXPECTEDSUBMISSION DATE).XNoEXPECTEDSUBMISSION DATE(15)MONTHOAYYEARABSTRACT(Umitto1400spaces,l.e.,approximately 15single-spaced tYpewritten lines)(16)OnJanuary4,1998,Unit1wasatzeropercentpower,inMode3,withpressurizer pressurelessthan1750psig.Areactorplantheatuptonormaloperating temperature andpressurefollowing refueling wasinprogress. | | Corrective actions included procedural enhancements, counseling the operator, and crew briefings on the event.NRC FORM 366{4.9S) |
| Thereactortripbreakerswereclosedandallreactorcontrolelementassemblies werefullyinserted.
| | NRC FORM 366A I4.9S)LICENSEE EVENT REPORT (LER)TEXT CONTINUATION U.S.NUCLEAR REGULATORY COMMISSIO ST.LUCIE UNIT 1 05000335 YEAR SEQUENTIAL REVISION 98-001-0 2 OF 4 TEXT/if more spece is required, use eddidonel copies of NRC Form 36@A/I17]On January 4, 1998, Unit 1 was at zero percent power, in Mode 3, with pressurizer pressure less than 1750 psig.A reactor plant heatup to normal operating temperature and pressure following refueling was in progress in accordance with Normal Operating Procedure NOP-1-0030121,"Reactor Plant Heatup-Cold to Hot Standby." Reactor Coolant System (RCS)temperature was approximately 510'F and pressure was approximately 1700 psia.Reactor Trip Circuit Breakers (TCBs)[EIIS:JC:BKR] |
| Theoperators weredirectedtoremovethezeropowermodebypasskeysforeachchannelofthereactorprotection systemoncethefourthreactorcoolantpumpwasstarted.Thereactortripbreakersopenedimmediately afterthereactorprotection system'C'hannel zeropowermodebypasswasunbypassed.
| | were closed and all reactor Control Element Assemblies (CEAs)[EIIS:AA]were fully inserted.The fourth Reactor Coolant Pump (RCP)[EIIS:AB:P], 1A1, was successfully started in accordance with step 6.5.12 of the heatup procedure. |
| Thiseventwascausedbyprocedural inadequacies andinadequate self-checking bylicensedutilitypersonnel.
| | Step 6.5.13 directs an operator to remove the Zero Power Mode Bypass (ZPMB)[EIIS:JC:33] |
| Theprocedure didnotaddressplantconditions necessary toensurethereactorprotection systemthermalmarginflow pressuretripsetpointwasbelowactualsystempressurewhenthezeropowermodebypasskeyswereoperated.
| | keys for each channel of the Reactor Protection System (RPS)[EIIS:JC]once the fourth RCP is started.At 1050, the reactor operator turned the ZPMB key from bypass to off for RPS channel'A'nd the Thermal Margin/Low Pressure (TM/LP)trip locked in.The reactor operator continued ,with the procedure and turned the ZPMB key from bypass to off for RPS channels'B','C', and'D'n sequence.It was then noted that the TCBs had opened, and it was confirmed via the Sequence of Events Recorder (SOER)[EIIS:IQ]that the TCBs had opened immediately after RPS channel'C'as unbypassed. |
| Duringtheevent,plantconditions wouldhavesetthethermalmargin/low pressuretripsetpointat1887psia,andactualreactorcoolantsystempressurewasapproximately 1740psiawhenthereactorprotection systemzeropowermodebypasswasunbypassed.
| | The operators immediately returned the ZPMB keys back to the bypass position.This event was caused by procedural inadequacies in procedure NOP 1-0030121,"Reactor Plant Heatup-Cold to Hot Standby." Inadequate self-checking by licensed utility personnel contributed to this event.Procedure NOP 1-0030121,"Reactor Plant Heatup-Cold to Hot Standby," step 6.5.13, directs the operators to place the ZPMB key from bypass to off after the fourth RCP is started.However, the procedure did not address all trip functions potentially bypassed by the ZPMB key.The ZPMB switch is a key operated switch, one for each RPS channel.The ZPMB allows the RPS low flow and TM/LP trips to be bypassed for subcritical testing of control element drive mechanisms; This RPS bypass is automatically removed when reactor power level increases above one percent power.The low flow trip is provided to protect the core against Departure from Nucleate Boiling (DNB)in the event of a coolant flow decrease.The low flow trip is a function of measured differential. |
| Additionally, theoperatorcontinued withtheunbypassing ofthezeropowermodebypassanddidnotgivethecrewtimetoreviewthevalidityofthealarmsandensureallconditions weresatisfactory priortocompleting theprocedure. | | pressure across the steam generators and the number of operating RCPs.NRC FORM 366A (4-9S) y1 NRC FORM 366A I4.96)LICENSEE EVENT REPORT (LER)TEXT CONTINUATION U.S.NUCLEAR REGULATORY COMMISSIO ST.LUCIE UNIT 1 05000335 YEAR SEQUENTIAL REVISION 98-001-0 3 OF 4 TEXT llf more speceis required, use edditionel copies of fVRC Form 3MAI I17I CAUSE OF THE EVENT cont'd The TIVI/LP trip is provided for two purposes.The low pressurizer pressure portion of the trip functions to trip the reactor in the event of a loss of coolant accident.The thermal margin portion of the trip, in conjunction. |
| Corrective actionsincludedprocedural enhancements, counseling theoperator, andcrewbriefings ontheevent.NRCFORM366{4.9S) | | with the low reactor coolant flow trip, is designed to prevent the reactor core safety limit on DNB from being violated during anticipated operational occurrences. |
| NRCFORM366AI4.9S)LICENSEEEVENTREPORT(LER)TEXTCONTINUATION U.S.NUCLEARREGULATORY COMMISSIO ST.LUCIEUNIT105000335YEARSEQUENTIAL REVISION98-001-02OF4TEXT/ifmorespeceisrequired, useeddidonel copiesofNRCForm36@A/I17]OnJanuary4,1998,Unit1wasatzeropercentpower,inMode3,withpressurizer pressurelessthan1750psig.Areactorplantheatuptonormaloperating temperature andpressurefollowing refueling wasinprogressinaccordance withNormalOperating Procedure NOP-1-0030121, "ReactorPlantHeatup-ColdtoHotStandby."
| | The TM/LP trip setpoint is either a calculated pressure value based on RCS temperature, power and flow, or a minimum biased pressure value of 1887 psia.During the event, four RCPs were operating (ensuring that a low flow trip would not be present), but existing plant conditions set the TM/LP trip setpoint at the minimum biased pressure value of 1887 psia, The ZPMB keys were placed from bypass to off while RCS pressure was approximately 1740 psia, which resulted in the TM/LP trip and opening the reactor TCBs.Additionally, personnel error by the operator and operating crew resulted in not investigating the cause of the TM/LP alarms when they were received as the RPS channel ZPMB keys were sequentially placed from bypass to off.The operator continued with the procedure and did not give the crew time to review the validity of the alarms and ensure all conditions were satisfactory prior to completing the procedure. |
| ReactorCoolantSystem(RCS)temperature wasapproximately 510'Fandpressurewasapproximately 1700psia.ReactorTripCircuitBreakers(TCBs)[EIIS:JC:BKR]
| | The TCBs opened when the third RPS channel ZPMB key was placed from bypass to off, which completed the coincidence requirements for the TM/LP reactor trip.St.Lucie Plant management expectations for licensed operator response to unexpected control room alarms are that the licensed operator acknowledging the alarm announce the alarm to control room personnel as"unexpected," that control room activities stop to permit investigation of the alarm, and that actions are taken in accordance with plant alarm response procedures to determine the cause of the alarm.Such activities did not occur during this event.This event is reportable as a valid actuation of the RPS per 10 CFR 50.73(a)(2)(iv). |
| wereclosedandallreactorControlElementAssemblies (CEAs)[EIIS:AA]
| | Since removing the bypass from the ZPMB restored the capability of the TM/LP trip circuitry to respond to an RCS low pressure condition, this event is considered a valid RPS actuation based on actual plant conditions. |
| werefullyinserted.
| | It was reported to the NRC as a four hour ENS notification at 1708 hours on January 5, 1998.The reactor was shutdown in Hot Standby prior to the event.Although the TCBs were opened by a valid RPS signal, the reactor trip signal did not result in any physical change to core reactivity because the CEAs were fully inserted prior to the trip signal.Therefore, this event had no impact to the health and safety of the public.NRC FOAM 388A I4.96) |
| ThefourthReactorCoolantPump(RCP)[EIIS:AB:P],
| | NRC FORM 366A I4-9SI LICENSEE EVENT REPORT (LER)TEXT CONTINUATION U.S.NUCLEAR REGULATORY COMMISSIO ST.LUCIE UNIT 1 05000335 YEAR SEQUENTIAL REVISION 98-001-0 4 OF 4 TEXT (If more speceis required, use eddilionel copies of ftVRC Rearm 366A j I17)2.Procedure changes to NOP 1-0030121 and NOP 2-0030121,"Reactor Plant Heatup-Cold to Hot Standby," were initiated to ensure that after the fourth RCP is started, the ZPMB bypass keys remain in bypass until pressure is greater than 1900 psia and no trips are present.i The operator was counseled, and the operator conducted briefings for each operating crew to describe the event in detail, including the seriousness of the event, the use of self checking, and the need for involvement from the operating crew when alarms are received.3.Placards have been placed in the control rooms that require either of the following conditions be met prior to placing the ZPMB keys from bypass to off: a)the reactor TCBS open, or b)the unit at normal operating temperature and pressure.None None NRC FORM 386A I4.95)}} |
| 1A1,wassuccessfully startedinaccordance withstep6.5.12oftheheatupprocedure. | |
| Step6.5.13directsanoperatortoremovetheZeroPowerModeBypass(ZPMB)[EIIS:JC:33]
| |
| keysforeachchanneloftheReactorProtection System(RPS)[EIIS:JC]
| |
| oncethefourthRCPisstarted.At1050,thereactoroperatorturnedtheZPMBkeyfrombypasstooffforRPSchannel'A'ndtheThermalMargin/Low Pressure(TM/LP)triplockedin.Thereactoroperatorcontinued
| |
| ,withtheprocedure andturnedtheZPMBkeyfrombypasstooffforRPSchannels'B','C',and'D'nsequence. | |
| ItwasthennotedthattheTCBshadopened,anditwasconfirmed viatheSequenceofEventsRecorder(SOER)[EIIS:IQ]
| |
| thattheTCBshadopenedimmediately afterRPSchannel'C'asunbypassed.
| |
| Theoperators immediately returnedtheZPMBkeysbacktothebypassposition.
| |
| Thiseventwascausedbyprocedural inadequacies inprocedure NOP1-0030121, "ReactorPlantHeatup-ColdtoHotStandby."
| |
| Inadequate self-checking bylicensedutilitypersonnel contributed tothisevent.Procedure NOP1-0030121, "ReactorPlantHeatup-ColdtoHotStandby," | |
| step6.5.13,directstheoperators toplacetheZPMBkeyfrombypasstooffafterthefourthRCPisstarted.However,theprocedure didnotaddressalltripfunctions potentially bypassedbytheZPMBkey.TheZPMBswitchisakeyoperatedswitch,oneforeachRPSchannel.TheZPMBallowstheRPSlowflowandTM/LPtripstobebypassedforsubcritical testingofcontrolelementdrivemechanisms; ThisRPSbypassisautomatically removedwhenreactorpowerlevelincreases aboveonepercentpower.ThelowflowtripisprovidedtoprotectthecoreagainstDeparture fromNucleateBoiling(DNB)intheeventofacoolantflowdecrease.
| |
| Thelowflowtripisafunctionofmeasureddifferential.
| |
| pressureacrossthesteamgenerators andthenumberofoperating RCPs.NRCFORM366A(4-9S) y1 NRCFORM366AI4.96)LICENSEEEVENTREPORT(LER)TEXTCONTINUATION U.S.NUCLEARREGULATORY COMMISSIO ST.LUCIEUNIT105000335YEARSEQUENTIAL REVISION98-001-03OF4TEXTllfmorespeceisrequired, useedditionel copiesoffVRCForm3MAII17ICAUSEOFTHEEVENTcont'dTheTIVI/LPtripisprovidedfortwopurposes.
| |
| Thelowpressurizer pressureportionofthetripfunctions totripthereactorintheeventofalossofcoolantaccident.
| |
| Thethermalmarginportionofthetrip,inconjunction.
| |
| withthelowreactorcoolantflowtrip,isdesignedtopreventthereactorcoresafetylimitonDNBfrombeingviolatedduringanticipated operational occurrences.
| |
| TheTM/LPtripsetpointiseitheracalculated pressurevaluebasedonRCStemperature, powerandflow,oraminimumbiasedpressurevalueof1887psia.Duringtheevent,fourRCPswereoperating (ensuring thatalowflowtripwouldnotbepresent),
| |
| butexistingplantconditions settheTM/LPtripsetpointattheminimumbiasedpressurevalueof1887psia,TheZPMBkeyswereplacedfrombypasstooffwhileRCSpressurewasapproximately 1740psia,whichresultedintheTM/LPtripandopeningthereactorTCBs.Additionally, personnel errorbytheoperatorandoperating crewresultedinnotinvestigating thecauseoftheTM/LPalarmswhentheywerereceivedastheRPSchannelZPMBkeysweresequentially placedfrombypasstooff.Theoperatorcontinued withtheprocedure anddidnotgivethecrewtimetoreviewthevalidityofthealarmsandensureallconditions weresatisfactory priortocompleting theprocedure.
| |
| TheTCBsopenedwhenthethirdRPSchannelZPMBkeywasplacedfrombypasstooff,whichcompleted thecoincidence requirements fortheTM/LPreactortrip.St.LuciePlantmanagement expectations forlicensedoperatorresponsetounexpected controlroomalarmsarethatthelicensedoperatoracknowledging thealarmannouncethealarmtocontrolroompersonnel as"unexpected,"
| |
| thatcontrolroomactivities stoptopermitinvestigation ofthealarm,andthatactionsaretakeninaccordance withplantalarmresponseprocedures todetermine thecauseofthealarm.Suchactivities didnotoccurduringthisevent.Thiseventisreportable asavalidactuation oftheRPSper10CFR50.73(a)(2)(iv).
| |
| SinceremovingthebypassfromtheZPMBrestoredthecapability oftheTM/LPtripcircuitry torespondtoanRCSlowpressurecondition, thiseventisconsidered avalidRPSactuation basedonactualplantconditions.
| |
| ItwasreportedtotheNRCasafourhourENSnotification at1708hoursonJanuary5,1998.ThereactorwasshutdowninHotStandbypriortotheevent.AlthoughtheTCBswereopenedbyavalidRPSsignal,thereactortripsignaldidnotresultinanyphysicalchangetocorereactivity becausetheCEAswerefullyinsertedpriortothetripsignal.Therefore, thiseventhadnoimpacttothehealthandsafetyofthepublic.NRCFOAM388AI4.96)
| |
| NRCFORM366AI4-9SILICENSEEEVENTREPORT(LER)TEXTCONTINUATION U.S.NUCLEARREGULATORY COMMISSIO ST.LUCIEUNIT105000335YEARSEQUENTIAL REVISION98-001-04OF4TEXT(Ifmorespeceisrequired, useeddilionel copiesofftVRCRearm366AjI17)2.Procedure changestoNOP1-0030121 andNOP2-0030121, "ReactorPlantHeatup-ColdtoHotStandby,"
| |
| wereinitiated toensurethatafterthefourthRCPisstarted,theZPMBbypasskeysremaininbypassuntilpressureisgreaterthan1900psiaandnotripsarepresent.iTheoperatorwascounseled, andtheoperatorconducted briefings foreachoperating crewtodescribetheeventindetail,including theseriousness oftheevent,theuseofselfchecking, andtheneedforinvolvement fromtheoperating crewwhenalarmsarereceived.
| |
| 3.Placardshavebeenplacedinthecontrolroomsthatrequireeitherofthefollowing conditions bemetpriortoplacingtheZPMBkeysfrombypasstooff:a)thereactorTCBSopen,orb)theunitatnormaloperating temperature andpressure. | |
| NoneNoneNRCFORM386AI4.95)}}
| |
|
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Category:LICENSEE EVENT REPORT (SEE ALSO AO
MONTHYEARML17241A4891999-10-0707 October 1999 LER 99-004-00:on 990912,noted That MSSV Surveillance Was Outside of TS Requirements.Caused by Setpoint Drift.Subject MSSVs Are Being Refurbished & Retested Prior to Unit Startup from SL1-16 Refueling Outage.With 991007 Ltr ML17241A4111999-07-16016 July 1999 LER 99-007-00:on 990610,unplanned Cooldown Transient Occurred Due to Personnel Error.Trained & Briefed Personnel & Revised Procedures.With 990716 Ltr ML17241A4031999-07-0606 July 1999 LER 99-006-00:on 990605,sub-critical Reactor Trip Occurred Due to Inadvertent MSIV Opening.Caused by Personnel Error. Provided Operation Supervision Instruction to Operating Crews,Stand Down Meetings & Operator Aids.With 990706 Ltr ML17241A4041999-07-0606 July 1999 LER 99-005-00:on 990604,CEA Drop Resulted in Manual Reactor Trip.Caused by Procedural Inadequacies.Procedure Changes Are Planned to Correct Lack of Procedural Guidance for CEA Subgroup Power Switch Replacement.With 990706 Ltr ML17241A3941999-06-30030 June 1999 LER 99-004-01:on 990415,as Found Cycle 10 Psv Setpoints Were Outside TS Limits.Caused by Manufacturing Process Defect. All Three Psvs Were Replaced with pre-tested Valves During Cycle 11 Refueling Outage.With 990630 Ltr ML17241A3551999-06-0404 June 1999 LER 99-002-00:on 990505,both Trains of Safety Injection Actuation Were Blocked During Surveillance.Caused by Procedure Error.Procedure Revised.With 990604 Ltr ML17241A3321999-05-17017 May 1999 LER 99-004-00:on 990415,determined That as Found Cycle 10 Psv Setpoints Outside TS Limits.Root Cause Under Investigation.Psvs Replaced with pe-tested Valves During Cycle 11 ML17241A3271999-05-0606 May 1999 LER 99-003-00:on 990406,ECCS Suction Header Leak Resulted in Both ECCS Trains Being Inoperable & Entry Into TS 3.0.3. Caused by Chloride Induced OD Stress Corrosion Cracking of Piping.Made Code Repairs & Coated Piping.With 990506 Ltr ML17229B0791999-04-0707 April 1999 LER 99-001-00:on 990309,discovered Inadequate Design & IST SRs for Iodine Removal Sys (Irs).Caused by Original Design Inadequacies & Personnel Error.Naoh Tank Vent Valve V07233 Was Tagged Open.With 990407 Ltr ML17229B0801999-04-0707 April 1999 LER 99-002-00:on 990311,SG ECT Error Caused Operation with Condition Prohibited by Ts.Caused by Deficiencies in Data Analysis Guideline Instructions.Licensee Will Change Data Analysis Guidelines for Lead Analysts.With 990407 Ltr ML17229B0541999-03-10010 March 1999 LER 99-001-00:on 990211,inadequate TS SRs for SIT & SDC Isolation Valves Were Noted.Caused by Failure to Correctly Implement TS Srs.Submitted LAR to Align Required TS SR with Design Bases Requirements Being Verified.With 990310 Ltr ML17229A9901999-01-20020 January 1999 LER 98-009-00:on 981223,noted That Facility Operated Outside of Design Basis.Caused by non-conservative MSLB Analysis Inputs.Will Review SR Component Differences Between Units & Will re-baseline LTOP Analysis.With 990120 Ltr ML17229A9821999-01-0404 January 1999 LER 98-010-00:on 981207,RCS Boron Sample Frequency Required by Ts,Was Exceeded by Twelve Minutes.Caused by Personnel Error.Equipment Clearance Order Was Lifted to Draw Required Sample & Operations Procedure Was Changed.With 990104 Ltr ML17229A9611998-12-22022 December 1998 LER 97-002-01:on 981204,containment Sump Debris Screen Was Not IAW Design.Caused by Inadequate C/As for Sump Screen Anamolies.All Identified Sump Screen Deficiencies Were Dispositioned &/Or Repaired.With 981222 Ltr ML17229A9561998-12-15015 December 1998 LER 98-008-00:on 981118,missed TS SG U Tube Insp.Caused by Encoding Errors While Using Remote Positioning Fixtures.All SG Tube Surveyed.With 981215 Ltr ML17229A9301998-11-25025 November 1998 LER 98-005-01:on 980807,discovered That New MOV Methodology Caused Past PORV Block Valve Operability Problem.Caused by Inadequacies in Original Vendor MOV Methodology.Planned Valve Mods Will Be Implemented During Cycle 11 1998 Outage ML17229A9021998-11-0404 November 1998 LER 98-008-00:on 981008,inadequate Reactor Protection Sys Trip Bypass TS Was Noted.Caused by Poorly Worded Ts. Submitted LAR to Clarify Power Requirements for High Rate of Power Trips.With 981104 Ltr ML17229A8771998-10-14014 October 1998 LER 98-006-00:on 980918,inadvertent Afas Actuation Was Noted.Caused by Degradation of Multiple Afas Power Supplies. Replaced Afas Power Supplies & Revised Procedures.With 981014 Ltr ML17229A8761998-10-14014 October 1998 LER 98-007-00:on 980918,identified Discrepancies Between Fire Protection Design Requirements & Field Conditions. Caused by Inadequate Translation & Implementation of Fire Protection Requirements.Procedures Revised.With 981014 Ltr ML17229A8511998-09-0202 September 1998 LER 98-005-00:on 980807,discovered That PORV Margins Were Insufficient to Accommodate Addl Conservatism.Caused by Inadequacies in Original Vendor MOV Methodology.Will Implement Planned Valve Actuator mods.W/980902 Ltr ML17229A8201998-07-29029 July 1998 LER 98-007-00:on 980630,inadequate Procedure May Have Resulted in SBO Recovery Complications.Caused by Inadequate Procedures.Attached Caution Tags to Appropriate Control switches.W/980729 Ltr ML17229A7411998-05-28028 May 1998 LER 98-004-00:on 980430,discovered Waste Gas Decay Tank Operation W/O Available Oxygen Analyzers,Which Is Prohibited by Ts.Caused by Inadequate Licensee Review of License Amend. Oxygen Analyzer recalibrated.W/980528 Ltr ML17229A7381998-05-21021 May 1998 LER 98-006-00:on 980421,missed EDG Fuel Oil Sample Surveillance Was Noted.Caused by Personnel Error.Revised Fuel Oil Sampling Service Purchase Order & Revised Site procedure.W/980521 Ltr ML17229A7011998-04-27027 April 1998 LER 98-003-00:on 980326,discovered Containment Pressure Instrumentation Design Single Failure Vulnerability.Caused by Inadequate Design by Personnel Error.Removed RPS & ESFAS Containment Pressure Bypass Keys immediately.W/980427 Ltr ML17229A6761998-04-0202 April 1998 LER 98-005-00:on 980305,identified Two Conditions That Were Outside App R Design Bases.Caused by Design Oversight During Development of Original App R Safe SD Design.Established 30 Minute Roving Fire Watches & Provided training.W/980402 Ltr ML17229A6731998-03-26026 March 1998 LER 98-002-00:on 980224,radiation Monitor Surveillance Inadequacies Led to Operating of Facility Prohibited by Tss. Caused by Congnitive Personnel Error.Permanent Procedure Changes Were implemented.W/980326 Ltr ML17229A6551998-03-0505 March 1998 LER 98-001-00:on 980206,high/low Pressure Shutdown Cooling Interface Was Noted Outside App R Design Bases.Caused by Personnel Error.Addl Guidance Was Provided to Engineering Dept personnel.W/980305 Ltr ML17229A6281998-02-19019 February 1998 LER 98-004-00:on 980121,emergency Lighting Outside App R Design Bases Occurred.Caused by Congnitive Personnel Error During Translation of App R Section Iii.Procedures Onop 1 & 2 ONP-100.01 Were Issued for Use on 980206.W/980219 Ltr ML17229A6211998-02-0909 February 1998 LER 98-003-00:on 980110,manual Rt Due to DEH Leak at Turbine Test Block Was Noted.Caused by o-ring Extrusion.Shortened Bolts by About 0.125 & Reinstalled at Correct Torque values.W/980209 Ltr ML17229A6191998-02-0404 February 1998 LER 98-002-00:on 980105,CIS Bistable in Bypass Resulted in Condition Prohibited by Tss.Caused by Personnel Error. Radiation Monitor Was Restored to service.W/980204 Ltr ML17229A6161998-02-0303 February 1998 LER 98-001-00:on 980104,inadvertent RPS Actuation Occurred Due to Personnel Error.Caused by Procedural Inadequacies & Inadequate self-checking by Licensed Utility Personnel. Placards Have Been Placed in CRs.W/980203 Ltr ML17229A6051998-01-27027 January 1998 LER 97-010-01:on 971027,inadvertent Core Alteration Prohibited by TSs Were Noted Due to Stuck Cea.Caused by Personnel Error.Cea #24 Was Dislodged & Transferred to Spent Pool for insp.W/980127 Ltr ML17229A5501997-12-0505 December 1997 LER 97-008-00:on 971107,inadequate CR Ventilation Surveillance Resulted in Condition Prohibited by Ts.Caused by non-cognitive Personnel Error.Operating Procedure 2-1900050 Was revised.W/971205 Ltr ML17309A9091997-12-0202 December 1997 LER 97-011-00:on 971102,non-conservative RAS Set Point Resulted in Operation Prohibited by Ts.Caused by Inadequate Set Point & Instrument Loop Scaling Process.Revised ESFAS Functional Tp W/Proper Set point.W/971202 Ltr ML17229A5391997-11-26026 November 1997 LER 97-010-00:on 971027,inadvertant Core Alteration Prohibited by TS Occurred.Caused by CEA Failure to Detach from Ugs.Safety Evaluation Was Performed & Procedural Rev Made to Continue Upper Guide Structure move.W/971126 Ltr ML17229A5151997-11-0707 November 1997 LER 97-007-00:on 971008,inoperable Containment Cooling Fan Resulted in Operation of Facility Outside Design Basis. Caused by non-cognitive Personnel Error.Ccs Operation Was Revised & Issued on 971013.W/971107 Ltr ML17229A4991997-10-17017 October 1997 LER 97-009-00:on 970917,inoperable PORV Block Valve Resulted in Operation Prohibited by Tech Specs Occurred.Caused by Plant GL 89-10 Program Plan to Review Plant Manager Action Item Sys.Porv Block Valve V-1403 restored.W/971017 Ltr ML17309A9011997-08-27027 August 1997 LER 97-008-00:on 970728,mechanical Fire Penetrations Were Inoperable & Outside App R Design Bases.Caused by Seal Mfg Not Providing Formal Documentation for Installed Seals. Modified Inoperable Fire penetrations.W/970827 Ltr ML17229A4311997-07-29029 July 1997 LER 97-006-00:on 970630,discovered Inadequate Testing of Engineered Safety Features Subgroup Relays.Caused by Inadequacy in Implementing TS Requirements in Surveillance Procedures.Revised Surveillance procedures.W/970729 Ltr ML17229A4241997-07-25025 July 1997 LER 97-005-00:on 970625,discovered That Hot Shutdown Control Panel Shutdown Cooling Flow indicator,FI-3306 Inoperable. Caused by Weakness in Work Order & Procedure Used to Repair FI-3306.Section Meeting W/I&C Planners held.W/970725 Ltr ML17229A3971997-07-11011 July 1997 LER 97-004-00:on 970611,discovered Incorrect Original Cable Tray Fire Stop Assembly Installation Was Outside App R Design Basis.Caused by Personnel Error.Hourly Fire Watch Patrols Will Be posted.W/970711 Ltr ML17229A3871997-06-19019 June 1997 LER 97-003-00:on 970521,determined Required Post Maint Open Stroke Test for Valve V3245,2B2 SIT Discharge Check Valve, Had Not Been Performed.Caused by Personnel Error.Procedure revised.W/970619 Ltr ML17229A3841997-06-17017 June 1997 LER 97-002-00:on 970518,containment Sump Debris Screen Was Not IAW Design Due to Gaps in Screen Encl.Performed SER to Document Containment Sump Design requirements.W/970617 Ltr ML17229A3751997-06-0202 June 1997 LER 97-006-00:on 970501,operation Was Prohibited by TS Due to Inadequately Tested Degraded Voltage Sys.Revised Unit 1 ESFAS Surveillance Test procedure.W/970602 Ltr ML17229A3611997-05-29029 May 1997 LER 97-007-00:on 970502,reactor Coolant Pump Oil Collection Sys Was Outside App R Design Bases.Identified Leak Sites Were Repaired & Mods to RCP Oil Collection Sys to Capture Any Future Leakage from areas.W/970529 Ltr ML17229A3491997-05-21021 May 1997 LER 97-001-00:on 970423,containment Isolation Actuation Occurred.Caused by Increased Radiation Levels During Removal of Upper Guide Structure.Proper Actuation of Containment Isolation Components Was verified.W/970521 Ltr ML17229A3441997-05-13013 May 1997 LER 97-005-00:on 970419,reactor Was Shutdown Due to Reactor Coolant Pressure Boundary Leakage.Hot Cracking Was Caused by Weld Contamination.Repairs to RCPB Were Completed & 1A SDC Train Was Restored to Svc ML17229A3141997-04-30030 April 1997 LER 97-004-00:on 970402,refueling Machine Was Operating in Manner Prohibited by TS Due to Original Design of Refueling Machine Bypass Feature Conflicting W/Ts Requirements. Eliminated Overload Cut Off Limit bypass.W/970430 Ltr ML17229A2951997-03-31031 March 1997 LER 97-003-00:on 970304,automatic Rt Resulted from Loss of Electrical Power to 1A2 Rc Pump.Rcp Breaker Was Replaced & Pump Was Returned to svc.W/970331 Ltr ML17229A2721997-03-21021 March 1997 LER 97-002-00:on 970221,operation in Excess of Max Rated Thermal Power Occurred Due to Digital Data Processing Sys (Ddps) Calorimetric Error.Verified Acceptable Performance of Ddps Functions & Reviewed Software mods.W/970321 Ltr 1999-07-06
[Table view] Category:RO)
MONTHYEARML17241A4891999-10-0707 October 1999 LER 99-004-00:on 990912,noted That MSSV Surveillance Was Outside of TS Requirements.Caused by Setpoint Drift.Subject MSSVs Are Being Refurbished & Retested Prior to Unit Startup from SL1-16 Refueling Outage.With 991007 Ltr ML17241A4111999-07-16016 July 1999 LER 99-007-00:on 990610,unplanned Cooldown Transient Occurred Due to Personnel Error.Trained & Briefed Personnel & Revised Procedures.With 990716 Ltr ML17241A4031999-07-0606 July 1999 LER 99-006-00:on 990605,sub-critical Reactor Trip Occurred Due to Inadvertent MSIV Opening.Caused by Personnel Error. Provided Operation Supervision Instruction to Operating Crews,Stand Down Meetings & Operator Aids.With 990706 Ltr ML17241A4041999-07-0606 July 1999 LER 99-005-00:on 990604,CEA Drop Resulted in Manual Reactor Trip.Caused by Procedural Inadequacies.Procedure Changes Are Planned to Correct Lack of Procedural Guidance for CEA Subgroup Power Switch Replacement.With 990706 Ltr ML17241A3941999-06-30030 June 1999 LER 99-004-01:on 990415,as Found Cycle 10 Psv Setpoints Were Outside TS Limits.Caused by Manufacturing Process Defect. All Three Psvs Were Replaced with pre-tested Valves During Cycle 11 Refueling Outage.With 990630 Ltr ML17241A3551999-06-0404 June 1999 LER 99-002-00:on 990505,both Trains of Safety Injection Actuation Were Blocked During Surveillance.Caused by Procedure Error.Procedure Revised.With 990604 Ltr ML17241A3321999-05-17017 May 1999 LER 99-004-00:on 990415,determined That as Found Cycle 10 Psv Setpoints Outside TS Limits.Root Cause Under Investigation.Psvs Replaced with pe-tested Valves During Cycle 11 ML17241A3271999-05-0606 May 1999 LER 99-003-00:on 990406,ECCS Suction Header Leak Resulted in Both ECCS Trains Being Inoperable & Entry Into TS 3.0.3. Caused by Chloride Induced OD Stress Corrosion Cracking of Piping.Made Code Repairs & Coated Piping.With 990506 Ltr ML17229B0791999-04-0707 April 1999 LER 99-001-00:on 990309,discovered Inadequate Design & IST SRs for Iodine Removal Sys (Irs).Caused by Original Design Inadequacies & Personnel Error.Naoh Tank Vent Valve V07233 Was Tagged Open.With 990407 Ltr ML17229B0801999-04-0707 April 1999 LER 99-002-00:on 990311,SG ECT Error Caused Operation with Condition Prohibited by Ts.Caused by Deficiencies in Data Analysis Guideline Instructions.Licensee Will Change Data Analysis Guidelines for Lead Analysts.With 990407 Ltr ML17229B0541999-03-10010 March 1999 LER 99-001-00:on 990211,inadequate TS SRs for SIT & SDC Isolation Valves Were Noted.Caused by Failure to Correctly Implement TS Srs.Submitted LAR to Align Required TS SR with Design Bases Requirements Being Verified.With 990310 Ltr ML17229A9901999-01-20020 January 1999 LER 98-009-00:on 981223,noted That Facility Operated Outside of Design Basis.Caused by non-conservative MSLB Analysis Inputs.Will Review SR Component Differences Between Units & Will re-baseline LTOP Analysis.With 990120 Ltr ML17229A9821999-01-0404 January 1999 LER 98-010-00:on 981207,RCS Boron Sample Frequency Required by Ts,Was Exceeded by Twelve Minutes.Caused by Personnel Error.Equipment Clearance Order Was Lifted to Draw Required Sample & Operations Procedure Was Changed.With 990104 Ltr ML17229A9611998-12-22022 December 1998 LER 97-002-01:on 981204,containment Sump Debris Screen Was Not IAW Design.Caused by Inadequate C/As for Sump Screen Anamolies.All Identified Sump Screen Deficiencies Were Dispositioned &/Or Repaired.With 981222 Ltr ML17229A9561998-12-15015 December 1998 LER 98-008-00:on 981118,missed TS SG U Tube Insp.Caused by Encoding Errors While Using Remote Positioning Fixtures.All SG Tube Surveyed.With 981215 Ltr ML17229A9301998-11-25025 November 1998 LER 98-005-01:on 980807,discovered That New MOV Methodology Caused Past PORV Block Valve Operability Problem.Caused by Inadequacies in Original Vendor MOV Methodology.Planned Valve Mods Will Be Implemented During Cycle 11 1998 Outage ML17229A9021998-11-0404 November 1998 LER 98-008-00:on 981008,inadequate Reactor Protection Sys Trip Bypass TS Was Noted.Caused by Poorly Worded Ts. Submitted LAR to Clarify Power Requirements for High Rate of Power Trips.With 981104 Ltr ML17229A8771998-10-14014 October 1998 LER 98-006-00:on 980918,inadvertent Afas Actuation Was Noted.Caused by Degradation of Multiple Afas Power Supplies. Replaced Afas Power Supplies & Revised Procedures.With 981014 Ltr ML17229A8761998-10-14014 October 1998 LER 98-007-00:on 980918,identified Discrepancies Between Fire Protection Design Requirements & Field Conditions. Caused by Inadequate Translation & Implementation of Fire Protection Requirements.Procedures Revised.With 981014 Ltr ML17229A8511998-09-0202 September 1998 LER 98-005-00:on 980807,discovered That PORV Margins Were Insufficient to Accommodate Addl Conservatism.Caused by Inadequacies in Original Vendor MOV Methodology.Will Implement Planned Valve Actuator mods.W/980902 Ltr ML17229A8201998-07-29029 July 1998 LER 98-007-00:on 980630,inadequate Procedure May Have Resulted in SBO Recovery Complications.Caused by Inadequate Procedures.Attached Caution Tags to Appropriate Control switches.W/980729 Ltr ML17229A7411998-05-28028 May 1998 LER 98-004-00:on 980430,discovered Waste Gas Decay Tank Operation W/O Available Oxygen Analyzers,Which Is Prohibited by Ts.Caused by Inadequate Licensee Review of License Amend. Oxygen Analyzer recalibrated.W/980528 Ltr ML17229A7381998-05-21021 May 1998 LER 98-006-00:on 980421,missed EDG Fuel Oil Sample Surveillance Was Noted.Caused by Personnel Error.Revised Fuel Oil Sampling Service Purchase Order & Revised Site procedure.W/980521 Ltr ML17229A7011998-04-27027 April 1998 LER 98-003-00:on 980326,discovered Containment Pressure Instrumentation Design Single Failure Vulnerability.Caused by Inadequate Design by Personnel Error.Removed RPS & ESFAS Containment Pressure Bypass Keys immediately.W/980427 Ltr ML17229A6761998-04-0202 April 1998 LER 98-005-00:on 980305,identified Two Conditions That Were Outside App R Design Bases.Caused by Design Oversight During Development of Original App R Safe SD Design.Established 30 Minute Roving Fire Watches & Provided training.W/980402 Ltr ML17229A6731998-03-26026 March 1998 LER 98-002-00:on 980224,radiation Monitor Surveillance Inadequacies Led to Operating of Facility Prohibited by Tss. Caused by Congnitive Personnel Error.Permanent Procedure Changes Were implemented.W/980326 Ltr ML17229A6551998-03-0505 March 1998 LER 98-001-00:on 980206,high/low Pressure Shutdown Cooling Interface Was Noted Outside App R Design Bases.Caused by Personnel Error.Addl Guidance Was Provided to Engineering Dept personnel.W/980305 Ltr ML17229A6281998-02-19019 February 1998 LER 98-004-00:on 980121,emergency Lighting Outside App R Design Bases Occurred.Caused by Congnitive Personnel Error During Translation of App R Section Iii.Procedures Onop 1 & 2 ONP-100.01 Were Issued for Use on 980206.W/980219 Ltr ML17229A6211998-02-0909 February 1998 LER 98-003-00:on 980110,manual Rt Due to DEH Leak at Turbine Test Block Was Noted.Caused by o-ring Extrusion.Shortened Bolts by About 0.125 & Reinstalled at Correct Torque values.W/980209 Ltr ML17229A6191998-02-0404 February 1998 LER 98-002-00:on 980105,CIS Bistable in Bypass Resulted in Condition Prohibited by Tss.Caused by Personnel Error. Radiation Monitor Was Restored to service.W/980204 Ltr ML17229A6161998-02-0303 February 1998 LER 98-001-00:on 980104,inadvertent RPS Actuation Occurred Due to Personnel Error.Caused by Procedural Inadequacies & Inadequate self-checking by Licensed Utility Personnel. Placards Have Been Placed in CRs.W/980203 Ltr ML17229A6051998-01-27027 January 1998 LER 97-010-01:on 971027,inadvertent Core Alteration Prohibited by TSs Were Noted Due to Stuck Cea.Caused by Personnel Error.Cea #24 Was Dislodged & Transferred to Spent Pool for insp.W/980127 Ltr ML17229A5501997-12-0505 December 1997 LER 97-008-00:on 971107,inadequate CR Ventilation Surveillance Resulted in Condition Prohibited by Ts.Caused by non-cognitive Personnel Error.Operating Procedure 2-1900050 Was revised.W/971205 Ltr ML17309A9091997-12-0202 December 1997 LER 97-011-00:on 971102,non-conservative RAS Set Point Resulted in Operation Prohibited by Ts.Caused by Inadequate Set Point & Instrument Loop Scaling Process.Revised ESFAS Functional Tp W/Proper Set point.W/971202 Ltr ML17229A5391997-11-26026 November 1997 LER 97-010-00:on 971027,inadvertant Core Alteration Prohibited by TS Occurred.Caused by CEA Failure to Detach from Ugs.Safety Evaluation Was Performed & Procedural Rev Made to Continue Upper Guide Structure move.W/971126 Ltr ML17229A5151997-11-0707 November 1997 LER 97-007-00:on 971008,inoperable Containment Cooling Fan Resulted in Operation of Facility Outside Design Basis. Caused by non-cognitive Personnel Error.Ccs Operation Was Revised & Issued on 971013.W/971107 Ltr ML17229A4991997-10-17017 October 1997 LER 97-009-00:on 970917,inoperable PORV Block Valve Resulted in Operation Prohibited by Tech Specs Occurred.Caused by Plant GL 89-10 Program Plan to Review Plant Manager Action Item Sys.Porv Block Valve V-1403 restored.W/971017 Ltr ML17309A9011997-08-27027 August 1997 LER 97-008-00:on 970728,mechanical Fire Penetrations Were Inoperable & Outside App R Design Bases.Caused by Seal Mfg Not Providing Formal Documentation for Installed Seals. Modified Inoperable Fire penetrations.W/970827 Ltr ML17229A4311997-07-29029 July 1997 LER 97-006-00:on 970630,discovered Inadequate Testing of Engineered Safety Features Subgroup Relays.Caused by Inadequacy in Implementing TS Requirements in Surveillance Procedures.Revised Surveillance procedures.W/970729 Ltr ML17229A4241997-07-25025 July 1997 LER 97-005-00:on 970625,discovered That Hot Shutdown Control Panel Shutdown Cooling Flow indicator,FI-3306 Inoperable. Caused by Weakness in Work Order & Procedure Used to Repair FI-3306.Section Meeting W/I&C Planners held.W/970725 Ltr ML17229A3971997-07-11011 July 1997 LER 97-004-00:on 970611,discovered Incorrect Original Cable Tray Fire Stop Assembly Installation Was Outside App R Design Basis.Caused by Personnel Error.Hourly Fire Watch Patrols Will Be posted.W/970711 Ltr ML17229A3871997-06-19019 June 1997 LER 97-003-00:on 970521,determined Required Post Maint Open Stroke Test for Valve V3245,2B2 SIT Discharge Check Valve, Had Not Been Performed.Caused by Personnel Error.Procedure revised.W/970619 Ltr ML17229A3841997-06-17017 June 1997 LER 97-002-00:on 970518,containment Sump Debris Screen Was Not IAW Design Due to Gaps in Screen Encl.Performed SER to Document Containment Sump Design requirements.W/970617 Ltr ML17229A3751997-06-0202 June 1997 LER 97-006-00:on 970501,operation Was Prohibited by TS Due to Inadequately Tested Degraded Voltage Sys.Revised Unit 1 ESFAS Surveillance Test procedure.W/970602 Ltr ML17229A3611997-05-29029 May 1997 LER 97-007-00:on 970502,reactor Coolant Pump Oil Collection Sys Was Outside App R Design Bases.Identified Leak Sites Were Repaired & Mods to RCP Oil Collection Sys to Capture Any Future Leakage from areas.W/970529 Ltr ML17229A3491997-05-21021 May 1997 LER 97-001-00:on 970423,containment Isolation Actuation Occurred.Caused by Increased Radiation Levels During Removal of Upper Guide Structure.Proper Actuation of Containment Isolation Components Was verified.W/970521 Ltr ML17229A3441997-05-13013 May 1997 LER 97-005-00:on 970419,reactor Was Shutdown Due to Reactor Coolant Pressure Boundary Leakage.Hot Cracking Was Caused by Weld Contamination.Repairs to RCPB Were Completed & 1A SDC Train Was Restored to Svc ML17229A3141997-04-30030 April 1997 LER 97-004-00:on 970402,refueling Machine Was Operating in Manner Prohibited by TS Due to Original Design of Refueling Machine Bypass Feature Conflicting W/Ts Requirements. Eliminated Overload Cut Off Limit bypass.W/970430 Ltr ML17229A2951997-03-31031 March 1997 LER 97-003-00:on 970304,automatic Rt Resulted from Loss of Electrical Power to 1A2 Rc Pump.Rcp Breaker Was Replaced & Pump Was Returned to svc.W/970331 Ltr ML17229A2721997-03-21021 March 1997 LER 97-002-00:on 970221,operation in Excess of Max Rated Thermal Power Occurred Due to Digital Data Processing Sys (Ddps) Calorimetric Error.Verified Acceptable Performance of Ddps Functions & Reviewed Software mods.W/970321 Ltr 1999-07-06
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARML17241A4891999-10-0707 October 1999 LER 99-004-00:on 990912,noted That MSSV Surveillance Was Outside of TS Requirements.Caused by Setpoint Drift.Subject MSSVs Are Being Refurbished & Retested Prior to Unit Startup from SL1-16 Refueling Outage.With 991007 Ltr ML17241A4951999-09-30030 September 1999 Monthly Operating Repts for Sept 1999 for St Lucie,Units 1 & 2.With 991014 Ltr ML17241A4741999-08-31031 August 1999 Rev 1 to PCM 99016, St Lucie Unit 1,Cycle 16 Colr. ML17241A4591999-08-31031 August 1999 Monthly Operating Repts for Aug 1999 for St Lucie,Units 1 & 2.With 990913 Ltr ML17241A4301999-07-31031 July 1999 Monthly Operating Repts for Jul 1999 for St Lucie Units 1 & 2.With 990805 Ltr ML17241A4111999-07-16016 July 1999 LER 99-007-00:on 990610,unplanned Cooldown Transient Occurred Due to Personnel Error.Trained & Briefed Personnel & Revised Procedures.With 990716 Ltr ML17241A4031999-07-0606 July 1999 LER 99-006-00:on 990605,sub-critical Reactor Trip Occurred Due to Inadvertent MSIV Opening.Caused by Personnel Error. Provided Operation Supervision Instruction to Operating Crews,Stand Down Meetings & Operator Aids.With 990706 Ltr ML17241A4041999-07-0606 July 1999 LER 99-005-00:on 990604,CEA Drop Resulted in Manual Reactor Trip.Caused by Procedural Inadequacies.Procedure Changes Are Planned to Correct Lack of Procedural Guidance for CEA Subgroup Power Switch Replacement.With 990706 Ltr ML17241A4091999-06-30030 June 1999 Monthly Operating Repts for June 1999 for St Lucie,Units 1 & 2.With 990712 Ltr ML17241A3941999-06-30030 June 1999 LER 99-004-01:on 990415,as Found Cycle 10 Psv Setpoints Were Outside TS Limits.Caused by Manufacturing Process Defect. All Three Psvs Were Replaced with pre-tested Valves During Cycle 11 Refueling Outage.With 990630 Ltr ML17355A3681999-06-30030 June 1999 Revised Update to Topical QA Rept, Dtd June 1999 ML17241A3551999-06-0404 June 1999 LER 99-002-00:on 990505,both Trains of Safety Injection Actuation Were Blocked During Surveillance.Caused by Procedure Error.Procedure Revised.With 990604 Ltr ML17241A3631999-05-31031 May 1999 Monthly Operating Repts for May 1999 for St Lucie Units 1 & 2.With 990610 Ltr ML17241A3321999-05-17017 May 1999 LER 99-004-00:on 990415,determined That as Found Cycle 10 Psv Setpoints Outside TS Limits.Root Cause Under Investigation.Psvs Replaced with pe-tested Valves During Cycle 11 ML17241A3271999-05-0606 May 1999 LER 99-003-00:on 990406,ECCS Suction Header Leak Resulted in Both ECCS Trains Being Inoperable & Entry Into TS 3.0.3. Caused by Chloride Induced OD Stress Corrosion Cracking of Piping.Made Code Repairs & Coated Piping.With 990506 Ltr ML17241A3331999-04-30030 April 1999 Monthly Operating Rept for Apr 1999 for St Lucie,Units 1 & 2.With 990517 Ltr ML17229B0801999-04-0707 April 1999 LER 99-002-00:on 990311,SG ECT Error Caused Operation with Condition Prohibited by Ts.Caused by Deficiencies in Data Analysis Guideline Instructions.Licensee Will Change Data Analysis Guidelines for Lead Analysts.With 990407 Ltr ML17229B0841999-04-0707 April 1999 Rev 2 to PSL-ENG-SEMS-98-102, Engineering Evaluation of ECCS Suction Lines. ML17229B0791999-04-0707 April 1999 LER 99-001-00:on 990309,discovered Inadequate Design & IST SRs for Iodine Removal Sys (Irs).Caused by Original Design Inadequacies & Personnel Error.Naoh Tank Vent Valve V07233 Was Tagged Open.With 990407 Ltr ML17229B0961999-03-31031 March 1999 Monthly Operating Repts for Mar 1999 for St Lucie,Units 1 & 2.With 990408 Ltr ML17229B0541999-03-10010 March 1999 LER 99-001-00:on 990211,inadequate TS SRs for SIT & SDC Isolation Valves Were Noted.Caused by Failure to Correctly Implement TS Srs.Submitted LAR to Align Required TS SR with Design Bases Requirements Being Verified.With 990310 Ltr ML17229B0461999-02-28028 February 1999 Monthly Operating Repts for Feb 1999 for St Lucie,Units 1 & 2.With 990310 Ltr ML17229B0051999-01-31031 January 1999 Monthly Operating Repts for Jan 1999 for St Lucie,Units 1 & 2.With 990211 Ltr ML17229A9901999-01-20020 January 1999 LER 98-009-00:on 981223,noted That Facility Operated Outside of Design Basis.Caused by non-conservative MSLB Analysis Inputs.Will Review SR Component Differences Between Units & Will re-baseline LTOP Analysis.With 990120 Ltr ML17229A9961999-01-14014 January 1999 SG Tube Inservice Insp Special Rept. ML17229A9821999-01-0404 January 1999 LER 98-010-00:on 981207,RCS Boron Sample Frequency Required by Ts,Was Exceeded by Twelve Minutes.Caused by Personnel Error.Equipment Clearance Order Was Lifted to Draw Required Sample & Operations Procedure Was Changed.With 990104 Ltr ML17229A9831998-12-31031 December 1998 Monthly Operating Repts for Dec 1998 for St Lucie,Units 1 & 2.With 990111 Ltr ML17229A9611998-12-22022 December 1998 LER 97-002-01:on 981204,containment Sump Debris Screen Was Not IAW Design.Caused by Inadequate C/As for Sump Screen Anamolies.All Identified Sump Screen Deficiencies Were Dispositioned &/Or Repaired.With 981222 Ltr ML17229A9561998-12-15015 December 1998 LER 98-008-00:on 981118,missed TS SG U Tube Insp.Caused by Encoding Errors While Using Remote Positioning Fixtures.All SG Tube Surveyed.With 981215 Ltr ML17241A3581998-12-0909 December 1998 Changes,Tests & Experiments Made as Allowed by 10CFR50.59 for Period of 970526-981209. ML17229A9421998-11-30030 November 1998 Monthly Operating Repts for Nov 1998 for St Lucie,Units 1 & 2.With 981215 Ltr ML17229A9301998-11-25025 November 1998 LER 98-005-01:on 980807,discovered That New MOV Methodology Caused Past PORV Block Valve Operability Problem.Caused by Inadequacies in Original Vendor MOV Methodology.Planned Valve Mods Will Be Implemented During Cycle 11 1998 Outage ML17229A9021998-11-0404 November 1998 LER 98-008-00:on 981008,inadequate Reactor Protection Sys Trip Bypass TS Was Noted.Caused by Poorly Worded Ts. Submitted LAR to Clarify Power Requirements for High Rate of Power Trips.With 981104 Ltr ML17241A4931998-11-0101 November 1998 Statement of Account for Period of 981101-990930 for Suntrust Bank,As Trustee for Florida Municipal Power Agency Nuclear Decommissioning Trust (St Lucie Project). ML17229A9051998-10-31031 October 1998 Monthly Operating Repts for Oct 1998 for St Lucie,Units 1 & 2.With 981110 Ltr ML17229A8871998-10-19019 October 1998 Part 21 Rept Re Potential Defect in Swagelok Stainless Steel Front Ferrule,Part Number SS-503-1 Which Was Machined with Improper Length.C/A Includes Insp Equipment That Will 100% Identify Short Length ML17229A8781998-10-19019 October 1998 Part 21 Rept Re Potential Defect in Swagelok Stainless Steel Front Ferrule,Part Number SS-503-1,which Was Machined with Improper Length.Insp Equipment That Will 100% Identify Short Length ML17229A8771998-10-14014 October 1998 LER 98-006-00:on 980918,inadvertent Afas Actuation Was Noted.Caused by Degradation of Multiple Afas Power Supplies. Replaced Afas Power Supplies & Revised Procedures.With 981014 Ltr ML17229A8761998-10-14014 October 1998 LER 98-007-00:on 980918,identified Discrepancies Between Fire Protection Design Requirements & Field Conditions. Caused by Inadequate Translation & Implementation of Fire Protection Requirements.Procedures Revised.With 981014 Ltr ML17229A8721998-09-30030 September 1998 Monthly Operating Repts for Sept 1998 for St Lucie Units 1 & 2.With 981009 Ltr ML17229A8511998-09-0202 September 1998 LER 98-005-00:on 980807,discovered That PORV Margins Were Insufficient to Accommodate Addl Conservatism.Caused by Inadequacies in Original Vendor MOV Methodology.Will Implement Planned Valve Actuator mods.W/980902 Ltr ML17229A8611998-08-31031 August 1998 Monthly Operating Repts for Aug 1998 for St Lucie,Units 1 & 2.With 980911 Ltr ML18066A2771998-08-13013 August 1998 Part 21 Rept Re Deficiency in CE Current Screening Methodology for Determining Limiting Fuel Assembly for Detailed PWR thermal-hydraulic Sa.Evaluations Were Performed for Affected Plants to Determine Effect of Deficiency ML17229A8481998-08-0707 August 1998 Rev 1 to PSL-ENG-SEFJ-98-013, St Lucie Unit 2,Cycle 10 Colr. ML17229A9461998-08-0707 August 1998 Rev 0 to PCM 98016, St Lucie Unit 2,Cycle 11 Colr. ML17229A8301998-07-31031 July 1998 Monthly Operating Repts for July 1998 for St Lucie,Units 1 & 2.W/980814 Ltr ML17229A8201998-07-29029 July 1998 LER 98-007-00:on 980630,inadequate Procedure May Have Resulted in SBO Recovery Complications.Caused by Inadequate Procedures.Attached Caution Tags to Appropriate Control switches.W/980729 Ltr ML17229A7981998-06-30030 June 1998 Monthly Operating Repts for June 1998 for St Lucie,Units 1 & 2.W/980713 Ltr ML17229A7701998-05-31031 May 1998 Monthly Operating Repts for May 1998 for St Lucie,Units 1 & 2.W/980612 Ltr ML17229A7411998-05-28028 May 1998 LER 98-004-00:on 980430,discovered Waste Gas Decay Tank Operation W/O Available Oxygen Analyzers,Which Is Prohibited by Ts.Caused by Inadequate Licensee Review of License Amend. Oxygen Analyzer recalibrated.W/980528 Ltr 1999-09-30
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CATEGORY 1~REGULARLY INFORMATION DISTRIBUTIOF%YSTEM (RIDS)p)*ACCESSION NBR:9802110012 DOC.DATE: 98/02/03 NOTARIZED:
NO FACIL:50-335 St.Lucie Plant, Unit 1, Florida Power&Light Co.AUTH.NAME AUTHOR AFFILIATION FREiIXFER,K.W.
Florida Power&Light Co.-STALL,J.A.
Florida Power&Light Co.RECIP.NAME RECIPIENT AFFILIATION DOCKET¹05000335
SUBJECT:
LER 98-001-00:on 980104,inadvertent RPS actuation occurred due to personnel error.Caused by procedural inadequacies
&, inadequate self-checking by.licensed utility personnel.
Placards have been placed in CRs.W/980203 ltr.DISTRIBUTION CODE: IE22T COPIES RECEIVED:LTR ENCL SIZE: TITLE: 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc.NOTES: 'C RECIPIENT ID CODE/NAME PD2-3 PD INTERNAL: ACRS AEOD/S PD/RRAB NRR/DE/ECGB NRR/DE/EMEB NRR/DRCH/HICB NRR/DRCH/HQMB NRR/DSSA/SPLB RES/DET/EIB EXTERNAL: L ST LOBBY WARD NOAC POORE,W.NRC PDR COPIES LTTR ENCL 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 RECIPIENT ID CODE/NAME WIENS,L.Cg NRR DE EELB NRR/DRCH/HHFB NRR/DRCH/HOLB NRR/DRPM/PECB NRR/DSSA/SRXB RGN2 FILE Ol LITCO BRYCE,J H NOAC QUEENER,DS NUDOCS FULL TXT COPIES LTTR ENCL 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 NOTE TO ALL"RIDS" RECIPIENTS:
PLEASE HELP US TO REDUCE WASTE.TO HAVE YOUR NAME OR ORGANIZATION REMOVED FROM DISTRIBUTION LIST>>OR REDUCE THE NUMBER OF COPIES RECEIVED BY YOU OR YOUR ORGANIZATION, CONTACT THE DOCUMENT CONTROI DESK (DCD)ON EXTENSION 415-2083 FULL TEXT CONVERSION REQUIRED TOTAL NUMBER OF COPIES REQUIRED: LTTR 25 ENCL 25 Florida Power&Light Company, 6351 S.Ocean Drive, Jensen Beach, FL 34957 February 3, 1998 L-98-018 10 CFR 50.73 U.S.Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C.20555 Re: St.Lucie Unit 1 Docket No.50-335 Reportable Event: 98-001 Date of Event: January 4, 1998 Inadvertent RPS Actuation Due to Personnel Error The attached Licensee Event Report is being submitted pursuant to the requirements of 10 CFR 50.73.Very truly yours, J.A.Stall Vice President St.Lucie Plant JAS/KWF Attachment cc: Regional Administrator, USNRC, Region II Senior Resident Inspector, USNRC, St.Lucie Plant'ir802ii0012
'rr80203 PDR ADQCK 05000335 8 PDR llllllllllllllllllllllllll llllllllllll an FPL Group company NRC FORM 366 (4.9e)U.S.NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)(See reverse for required number of digits/characters for each biock)APPROVED SV OMB No.S(60<0(O4 EXARES 04/30/S S ESTIMATED BURDEN PER RESPONSE TO COMPLY WITH THIS MANDATOR INFORMATION COLLECTION REOUEST: 60.0 HRS.REPORTED LESSON LEARNED ARE INCORPORATED INTO THE UCENSING PROCESS AND FE BACK TO INDUSTRY.FORWARD COMMENTS REGARDING BURDEN ESTIMAT TO THE INFORMATION AND RECORDS MANAGEMENT BRANCH (TW F33(US.NUCLEAR REGIAATORY COMMISSION, WASHINGTON, DC 20666ENO I AND TO THE PAPERWORK REDUCTION PROJECT (3(600104I, OFRCE 0 MANAGEMENT AND BUDGET, WASHINGTON, DC 20603.FACIUTY NAME UI ST LUCIE UNIT 1 TITLE (4I Inadvertent RPS Actuation Due to Personnel Error DOCKET NINVIB(R (2(05000335 PAGE (SI 1 OF4 DAY YEAR 4 98 YEAR SEOUENTIAL REVISION MONTH NUMBER NUMBER 98,-001-0 OAY YEAR 3 98 FACIUTY NAME FACIUTY NAME DOCKET NUMBER 05000 DOCKETNUMBER 05000 OPERATINQ MODE (9)POWER LEVEL l10)20.2201 (b)20.2203 (a)(2)6)20.2203{a)
(2)(iii)20.2203 (a)(2)(iv)20.2203(a) l2)(v)20.2203(a)
(3)(ii)50.36(c)(1)50.36(c)(2)50.73(a)l2){i)50.73(a)(2)(iii)50.73(a){2){v)50.73(a)(2)(vii) 50.73{0)l2)(viii)73.71 OTHER Specify In Abstract below or in NRC Form 366A NAME K.W.Frehafer, Licensing Engineer TELEPHONE NUMBER Src(vde Arta Codel (561)468-4284 CAUSE SYSTEM COMPONENT MANUFACTURER REPORTABLE TO NPRDS CAUSE SYSTEM COMPONENT MANUFACTURER To NPRDS JC N/A N/A N/A YES{It yes, complete EXPECTED SUBMISSION DATE).X No EXPECTED SUBMISSION DATE (15)MONTH OAY YEAR ABSTRACT (Umit to 1400 spaces, l.e., approximately 15 single-spaced tYpewritten lines)(16)On January 4, 1998, Unit 1 was at zero percent power, in Mode 3, with pressurizer pressure less than 1750 psig.A reactor plant heatup to normal operating temperature and pressure following refueling was in progress.The reactor trip breakers were closed and all reactor control element assemblies were fully inserted.The operators were directed to remove the zero power mode bypass keys for each channel of the reactor protection system once the fourth reactor coolant pump was started.The reactor trip breakers opened immediately after the reactor protection system'C'hannel zero power mode bypass was unbypassed.
This event was caused by procedural inadequacies and inadequate self-checking by licensed utility personnel.
The procedure did not address plant conditions necessary to ensure the reactor protection system thermal marginflow pressure trip setpoint was below actual system pressure when the zero power mode bypass keys were operated.During the event, plant conditions would have set the thermal margin/low pressure trip setpoint at 1887 psia, and actual reactor coolant system pressure was approximately 1740 psia when the reactor protection system zero power mode bypass was unbypassed.
Additionally, the operator continued with the unbypassing of the zero power mode bypass and did not give the crew time to review the validity of the alarms and ensure all conditions were satisfactory prior to completing the procedure.
Corrective actions included procedural enhancements, counseling the operator, and crew briefings on the event.NRC FORM 366{4.9S)
NRC FORM 366A I4.9S)LICENSEE EVENT REPORT (LER)TEXT CONTINUATION U.S.NUCLEAR REGULATORY COMMISSIO ST.LUCIE UNIT 1 05000335 YEAR SEQUENTIAL REVISION 98-001-0 2 OF 4 TEXT/if more spece is required, use eddidonel copies of NRC Form 36@A/I17]On January 4, 1998, Unit 1 was at zero percent power, in Mode 3, with pressurizer pressure less than 1750 psig.A reactor plant heatup to normal operating temperature and pressure following refueling was in progress in accordance with Normal Operating Procedure NOP-1-0030121,"Reactor Plant Heatup-Cold to Hot Standby." Reactor Coolant System (RCS)temperature was approximately 510'F and pressure was approximately 1700 psia.Reactor Trip Circuit Breakers (TCBs)[EIIS:JC:BKR]
were closed and all reactor Control Element Assemblies (CEAs)[EIIS:AA]were fully inserted.The fourth Reactor Coolant Pump (RCP)[EIIS:AB:P], 1A1, was successfully started in accordance with step 6.5.12 of the heatup procedure.
Step 6.5.13 directs an operator to remove the Zero Power Mode Bypass (ZPMB)[EIIS:JC:33]
keys for each channel of the Reactor Protection System (RPS)[EIIS:JC]once the fourth RCP is started.At 1050, the reactor operator turned the ZPMB key from bypass to off for RPS channel'A'nd the Thermal Margin/Low Pressure (TM/LP)trip locked in.The reactor operator continued ,with the procedure and turned the ZPMB key from bypass to off for RPS channels'B','C', and'D'n sequence.It was then noted that the TCBs had opened, and it was confirmed via the Sequence of Events Recorder (SOER)[EIIS:IQ]that the TCBs had opened immediately after RPS channel'C'as unbypassed.
The operators immediately returned the ZPMB keys back to the bypass position.This event was caused by procedural inadequacies in procedure NOP 1-0030121,"Reactor Plant Heatup-Cold to Hot Standby." Inadequate self-checking by licensed utility personnel contributed to this event.Procedure NOP 1-0030121,"Reactor Plant Heatup-Cold to Hot Standby," step 6.5.13, directs the operators to place the ZPMB key from bypass to off after the fourth RCP is started.However, the procedure did not address all trip functions potentially bypassed by the ZPMB key.The ZPMB switch is a key operated switch, one for each RPS channel.The ZPMB allows the RPS low flow and TM/LP trips to be bypassed for subcritical testing of control element drive mechanisms; This RPS bypass is automatically removed when reactor power level increases above one percent power.The low flow trip is provided to protect the core against Departure from Nucleate Boiling (DNB)in the event of a coolant flow decrease.The low flow trip is a function of measured differential.
pressure across the steam generators and the number of operating RCPs.NRC FORM 366A (4-9S) y1 NRC FORM 366A I4.96)LICENSEE EVENT REPORT (LER)TEXT CONTINUATION U.S.NUCLEAR REGULATORY COMMISSIO ST.LUCIE UNIT 1 05000335 YEAR SEQUENTIAL REVISION 98-001-0 3 OF 4 TEXT llf more speceis required, use edditionel copies of fVRC Form 3MAI I17I CAUSE OF THE EVENT cont'd The TIVI/LP trip is provided for two purposes.The low pressurizer pressure portion of the trip functions to trip the reactor in the event of a loss of coolant accident.The thermal margin portion of the trip, in conjunction.
with the low reactor coolant flow trip, is designed to prevent the reactor core safety limit on DNB from being violated during anticipated operational occurrences.
The TM/LP trip setpoint is either a calculated pressure value based on RCS temperature, power and flow, or a minimum biased pressure value of 1887 psia.During the event, four RCPs were operating (ensuring that a low flow trip would not be present), but existing plant conditions set the TM/LP trip setpoint at the minimum biased pressure value of 1887 psia, The ZPMB keys were placed from bypass to off while RCS pressure was approximately 1740 psia, which resulted in the TM/LP trip and opening the reactor TCBs.Additionally, personnel error by the operator and operating crew resulted in not investigating the cause of the TM/LP alarms when they were received as the RPS channel ZPMB keys were sequentially placed from bypass to off.The operator continued with the procedure and did not give the crew time to review the validity of the alarms and ensure all conditions were satisfactory prior to completing the procedure.
The TCBs opened when the third RPS channel ZPMB key was placed from bypass to off, which completed the coincidence requirements for the TM/LP reactor trip.St.Lucie Plant management expectations for licensed operator response to unexpected control room alarms are that the licensed operator acknowledging the alarm announce the alarm to control room personnel as"unexpected," that control room activities stop to permit investigation of the alarm, and that actions are taken in accordance with plant alarm response procedures to determine the cause of the alarm.Such activities did not occur during this event.This event is reportable as a valid actuation of the RPS per 10 CFR 50.73(a)(2)(iv).
Since removing the bypass from the ZPMB restored the capability of the TM/LP trip circuitry to respond to an RCS low pressure condition, this event is considered a valid RPS actuation based on actual plant conditions.
It was reported to the NRC as a four hour ENS notification at 1708 hours0.0198 days <br />0.474 hours <br />0.00282 weeks <br />6.49894e-4 months <br /> on January 5, 1998.The reactor was shutdown in Hot Standby prior to the event.Although the TCBs were opened by a valid RPS signal, the reactor trip signal did not result in any physical change to core reactivity because the CEAs were fully inserted prior to the trip signal.Therefore, this event had no impact to the health and safety of the public.NRC FOAM 388A I4.96)
NRC FORM 366A I4-9SI LICENSEE EVENT REPORT (LER)TEXT CONTINUATION U.S.NUCLEAR REGULATORY COMMISSIO ST.LUCIE UNIT 1 05000335 YEAR SEQUENTIAL REVISION 98-001-0 4 OF 4 TEXT (If more speceis required, use eddilionel copies of ftVRC Rearm 366A j I17)2.Procedure changes to NOP 1-0030121 and NOP 2-0030121,"Reactor Plant Heatup-Cold to Hot Standby," were initiated to ensure that after the fourth RCP is started, the ZPMB bypass keys remain in bypass until pressure is greater than 1900 psia and no trips are present.i The operator was counseled, and the operator conducted briefings for each operating crew to describe the event in detail, including the seriousness of the event, the use of self checking, and the need for involvement from the operating crew when alarms are received.3.Placards have been placed in the control rooms that require either of the following conditions be met prior to placing the ZPMB keys from bypass to off: a)the reactor TCBS open, or b)the unit at normal operating temperature and pressure.None None NRC FORM 386A I4.95)