ML17347B024

LER 89-004-00:on 890210,reactor Trip Occurred.Caused by Defective Procedure During Steam Generator Protection Channel Testing.Procedure OP 14004.1 Revised to Correct errors.W/890313 Ltr

ML17347B024
Person / Time
Site:	Turkey Point
Issue date:	03/13/1989
From:	Conway W, Mowrey C FLORIDA POWER & LIGHT CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
L-89-92, LER-89-004, LER-89-4, NUDOCS 8903230293
Download: ML17347B024 (6)

Text

AC CELE RATED DI St'RIBUTI ON DEMON STRATI O'.i SYSTEM REGULATOR NFORMATION DISTRIBUTION S EM (RIDS)

ACCESSION NBR:8903230293 DOC.DATE: 89/03/13 NOTARIZED: NO DOCKET FACIL:50'-250 Turkey Point Plant, Unit 3, Florida Power and Light C 05000250 AUTH. NAME AUTHOR AFFILIATION MOWREYgC. Florida Power & Light Co.

CONWAY,W.F. Florida Power & Light Co.

RECIP.NAME RECIPIENT AFFILIATION

SUBJECT:

LER 89-004-00:on 890210,reactor trip due to defective procedure during steam generator protection channel testing.

W/8 ltr.

DISTRIBUTION CODE: IE22D TITLE: 50.73 Licensee Event Report (LER),

COPIES RECEIVED:LTR + ENCL Inci ent Rpt,+etc.

SIZE:

NOTES:

RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD2-2 LA 1 1 PD2-2 PD 1 1 EDISON,G 1 1 INTERNAL: ACRS MICHELSON 1 1 ACRS MOELLER 2 2 ACRS WYLIE 1 1 AEOD/DOA 1 1 AEOD/DSP/TPAB ARM/DCTS/DAB NRR/DEST/ADE 8H 1

1 1

1 1

1 AEOD/ROAB/DSP DEDRO NRR/DEST/ADS 7E 1,

2 1

2 1

0 NRR/DEST/CEB 8H 1 1 NRR/DEST/ESB 8D 1 1 NRR/DEST/ICSB 7 1 1 NRR/DEST/MEB 9H 1 1 NRR/DEST/MTB 9H 1 1 NRR/DEST/PSB 8D 1 1 p~

NRR/DEST/RSB 8E 1 1 NRR/DEST/SGB 8D 1 1 NRR/DLPQ/HFB 10 1 1 NRR/DLPQ/QAB 10 1 1 NRR/DOEA/EAB 11 1 1 NRR/DREP/RAB 10 1 1 NRR/DREP/RPB 10 2 2 NRR/DRIS/SIB 9A 1 1 NUDOCS-ABSTRACT 1 1 1 1 RES/DSIR/EIB 1 1 RES/DSR/'PRA'B 1 1 RGN2 FILE 01 1 1 EXTERNAL EG&G WILLIAMSg S 4 4 FORD BLDG HOYgA 1 1 H ST LOBBY WARD 1 1 LPDR 1 1 NRC PDR 1 1 NSIC MAYS,G 1 1 NSIC MURPHYiG.A 1 1 NCTE K) ALL "RZDS" RECIPIENIS'IZASE HELP US 10 REDUCE HASTE CGHIACT '%HE DOCUKWZ CXKIROL DESKS RDCM Pl-37 (EXT. 20079) KO )KZMIMXR YOUR K@K HEN DZSTBIBVX'ZQN LISTS FOR DOC(METIS Y0U DON'T NEED!

0'OTAL NUMBER OF COPIES REQUIRED: LTTR 45 ENCL 44

NRC Form 345 UA. NUCLEAR REOULATORY CONSCISSION 1903) APPROVED OMS NO. 31500101 EXPIRES: S/31/44 LICENSEE EVENT REPORT ILER)

FACILITY NAME (I I DOCKET NUMSER (1) PA Turkey Point Unit 3 p 5 p p p 2 5 0 q pF 0 3 Reactor Trap Due o Defective procetlure During Steam Generator Protection-Channel Testing EVENT DATf. (Sl LER NUMSER IS) REPORT DATE (7) OTHER FACILITIES INVOLVED (4)

SEQUENTIAL jrx OAY YEAR FACILITYNAMES DOCKET NUMBER(3)

MONTH DAY YEAR YEAR NVMSEII rN NUM445 MONTH N/A 0 5 0 0 0 0 2 10 89 89 0 4 00 03 13 89 0 5 0 0 0 THIS REPORT IS SUSMITTED PURSVANT TO THE REOVIREMENTS OF 10 CFR (): ICSsck ons or more of ms INlorffnpl I'Ill OPERATINO MODE (4) 20.S02(4) 20.405(c) 50.734) (1l(hl 73.7101) 20A05(c)(1)(I) SODS(c) (ll 50,734)(2)(r) 73.71(c) 000 20A05(c) (I l(4) 50.34(cl(2) 50.73(s) 12)(r4) OTHER ISpcclfy in Asrtrect trcroe snd ln text, HIIC Form 20.405(sin((SII 50.734) (2) (II 50.734) (2)(rSII(A) 388AI 20A054) (()(h) 50.734) l2)(4) 50.73(sl(2)415)(S) 20.4054) (1)(r l 50.734)(2) (III) 50.73( ~ )(2)(x)

LICENSEE CONTACT FOR THIS LER (11)

NAME TELEPHONE NUMBER Craig IIIowrey, Regulation and Compliance Group 3V( 246 -69 71 COMPLE'TE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBEO IN THIS AEPORT 03)

MANUFAC. EPOATASLE

A)(cx+rro': MANUFAC. EPORTASL CAUSE SYSTEM COMPONENT CAUSE SYSI'EM COMPONENT TVAER TO NPADS TVRER TO NPADS n

r mrs SVPPLf MENTAL REPOA'7 EXPECTED (Isl MONTH DAY YEAR EXPECTED SVSMISSION DATE IISI YES III yrL complcrs EXPECTED SIIESIISSIDN DA PEI NO AssTAAcT (Limit ro ls00 Ipsccr, I.c., sppmximstcty fifteen Iinprscpscs typcwrtttrn tincrl (14)

On February 10, 1989, at 1151, with Unit 3 reactor critical at OX power (approximately 1 E -6 amps in the intermediate range) a reactor trip occurred . While performing procedure OP 14004.1 a bistable was placed in test causing the Reactor Protection System (EIIS:JC) to see power level greater than 10X, enabling the P-7 reactor trips. P-7 is a trip permissive, enabled whenever either reactor power or turbine power is greater than 10X. This, coincident with the turbine trip signal from the unlatched turbine, caused the reactor trip. The cause of the trip was a defective procedure in that the step which resulted in the trip was not identified as having the potential to cause a trip. A contributing cause was inadequate control of procedure replacements which allowed 'two applicable proc-edures to be in effect at the same time. An event response team was formed to determine root cause(s) and corrective actions . The old procedure was revised to correct the errors and was completed-to satisfy the surveillance requirement. The new procedures are being first-use verified, and work controls will be developed to ensure old procedures are cancelled in a timely manner.

8(7)032302'7)3 890313 PDR ADOCIE, 05000250 S PNU NRC Form 345 (9 83)

NRC Form 3ddA (983) U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER) TEXT CONTINUATION APPROVED OMB NO, 3)SOW)04 FACILITYNAME (11 DOCKET NUMBER l1)

LER NUMBER (d) PACE (3)

YEAR I@? sdovdNTIAL NVMddR ~pi: REVISION NVMddR Turkey Point Unit 3 0 5 0 0 0 250 8 9 004 0 0 02 OF 03 TEXT (If more efrece le rtuf)erL uee orfrflIHurefHRC Form 3EBA'Fl (17)

On February 10, 1989, at 1151, with Unit 3 critical at OX power(approximately 1 E -6 amps in the intermediate range), a reactor trip occurred. While performing procedure OP 14004.1, "Steam Generator Protection Channels Periodic Test", Unit 3 tripped when bistable BS-3-446-1 was placed in the test position in accordance with step 8.3.72 of the procedure . This caused the Reactor Protection System (EIIS:JC) to see a reactor power level of greater than 10X, enabling the P-7 reactor trips. P-7 is a trip permissive, enabled whenever either reactor power or turbine power is greater than 10X. The reactor then tripped due to the presence of the turbine trip signal (2/3 auto stop oil pressure). All systems functioned as designed; the plant was stabilized in Mode 3 (hot standby), and an Event Re-sponse Team (ERT) was convened to review the incident.

CAUSE OF EVENT The ERT investigation into the event determined that the primary cause of the event was procedural inadequacy in that the caution regarding the potential for a reactor trip listed wrong applicable step numbers, was not placed directly before the applicable steps, and was generally confusing. Specifically the caution stated that it applies to steps 8.3.76 through 8.4.84 whereas it actually applies to steps 8.3.72 through 8.4.84. Additionally it was placed immediately preceding step 8.3.71 rather than immediately preceding step 8.3.72.

A contributing factor was that two applicable procedures, OP 14004.1 and 3-SMI-071.4, were in effect at the same time . As part of Turkey Point s Procedure Upgrade Programe procedure OP 14004.1 was to be replaced by 3-SMI-071.4, and six other new procedures.

Plant policy allows continued use of the old procedure until the new procedure(s) have been first-use verified by a successful performance in the field. Although these new procedures had been approved and issued, they were not currently in use because they had not received their first-use test. New procedure 3"SMI-071.4 was written such that, had it been used, this trip would probably not have occurred.

Since the 'seven new procedures had not been completed, the plant s schedule of surveillances still listed OP 14004.1 as the surveillance procedure.

ANALYSIS OF EVENT A post-trip review was performed to assess the proper operation of safety-related equipment . The review established that there was no thermodynamic response to the trip and that plant parameters responded as, expected . Other than the automatic initiation'f the reactor trip, there were no manual or automatic NRC FORM 3ddA 1983)

NRC Form 3EEA U.S. NUCLEAR REOULATORY COMMISSION (8 83)

LICENSEE EVENT REPORT (LER) TEXT CONTINUATION APPROVED OMS NO. 319)W)OO EXPIRES: 8/31/88 FACILITY NAME (I) DOCKET NUMSER (3) LER NUMSER (81 PACE (3)

YEAR SEOUENTIAL REvlslorr Ng NUMSER IIUMEER Turkey Point Unit 3 o 6 o o o 8 9 004 00 03 OF 0 3 TEXT llfmore F/Mce ir r/I//rked, ere odd/dooo/ HRC %%drm 3R(A'F/ (17) reactor protection system or engineered safety features actuations. Based on the above, the health and safety of the public were not affected.

CORRECTIVE ACTIOHS

1) An ERT was formed to review the event and determine the root cause and corrective actions')

Procedure OP 14004.1 was revised to correct the errors, and the procedure was completed to satisfy the surveillance requirement .

3) The first-use test of the seven new replacement procedures will be performed and OP 14004.1 will be cancelled (six of the seven new procedures have been successfully completed on Unit 3). This action will be completed in time to sup-port the restart of Unit 4, presently scheduled for April 8, 1989.

4) Work controls will be developed to ensure old procedures are cancelled in a timely manner after new upgrade procedures are approved. This action will be completed by June 1, 1989.

ADDITIONAL I1(IPORMhTION Similar occurrences; LER 251-88-010 describes a reactor trip due to personnel error during the performance of OP 14004.1, and LER 250-86-030 describes a reactor trip and safety injection due to inadequate planning of postmaintenance testing associated with OP 14004.1.

NRC FORM 3EEA ISS3)

P.O. Box 14000, Juno Beech, FL 33408.0420 MARCH 1 tI 1989 L-89-92 10 CFR 50.73 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D. C. 20555 Gentlemen:

Re: Turkey Point Unit 3 Docket Nos. 50-250 Reportable Event: 250-89-04 Date of Event: February 10, 1989 Reactor Trip Due to Defective Procedure Durin Steam Generator Protection Channel Testin The attached Licensee Event Report (LER) is being submitted pursuant to the requirements of 10 CFR 50.73 to provide notification of the subject event.

Very truly yours, W. F. ay

@ Senior 'ce President Nuclear WFC/RHF/gp Attachment cc: Stewart D. Ebneter, Regional Administrator, Region IX, USNRC Senior Resident Inspector, USNRC, Turkey Point Plant

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