ML17304A259

Special Rept 1-SR-88-005:fire Occurred in Auxiliary Transformer Resulting in Loss of Nonclass 1E Ac Power.Fire Extinquished & Notification of Unusual Event Terminated.When Bus Energized,Second Fire Started.Plant Remained Stable

ML17304A259
Person / Time
Site:	Palo Verde
Issue date:	07/11/1988
From:	Haynes J ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
1-SR-88-005, 1-SR-88-5, 192-00393-JGH-T, 192-393-JGH-T, NUDOCS 8807180242
Download: ML17304A259 (6)

Text

AC CELE RA'~'M 51 4 ~ MB0 i'l U~ DE M OPi STATION SYSTEM REGUL INFORMATION DISTRIBUTI 'vSTEM (RIDS)

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.ACCESSION NBR:8807180242 DOC.DATE: 88/07/ll NOTARIZED: NO DOCKET FACIL:STN-50-528 Palo Verde Nuclear Station, Unit 1, Arizona Publi 05000528 AUTH. NAME AUTHOR AFFILIATION HAYNES,J.G. Arizona Nuclear Power Project (formerly Arizona Public Serv RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)

SUBJECT:

Special rept 1-SR-88-005 re notification of unusual event due to fire in Unit 1 auxiliary transformer.

DISTRIBUTION CODE: IE22D COPIES RECEIVED:LTR + ENCL \

TITLE: 50.73 Licensee Event Report (LER), Incident Rpt, etc.

SIZE:

D NOTES:Standardized plant. 05000528 8

RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD5 LA 1 1 PD5 PD 1 1 LICITRAgE 1 1 DAVIS,M 1 1 INTERNAL: ACRS MICHELSON 1 1 ACRS MOELLER 2 2 AEOD/DOA 1 1 AEOD/DSP/NAS 1 1 AEOD/DSP/ROAB 2. 2 AEOD/DSP/TPAB 1 1 ARM/DCTS/DAB 1 1 DEDRO 1 1 NRR/DEST/ADS 7E 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 NRR/DEST/RSB 8E 1 1 NRR/DEST/SGB NRR/DLPQ/QAB NRR/DREP/RAB 8D 10 10 1

1 1

1 1

1 NRR/DLPQ/HFB 10 NRR/DOEA/EAB NRR/DREP/RPB 10 ll 1 1

2 1

1 2

NRR R.RS~IB 9A 1 1 NUDOCS-ABSTRACT 1 1 REG~~ 02 1 1 RES TELFORDgJ RES/DRPS DEPY "1 1 1 1

RES/DE/EIB 1 1 RGN5 FILE 01 1 1 EXTERNAL: EG&G WILLIAMSiS 4 4 FORD BLDG HOY,A 1 1 H ST LOBBY WARD 1 1 LPDR 1 1 NRC PDR 1 1 NSIC HARRISgJ 1 1 NSIC MAYSgG 1 1 NOTES: 1 1 TOTAL NUMBER OF COPIES REQUIRED: LTTR 47 ENCL 46

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Arizona Nuclear Power Project P.O. BOX 52034 ~ PHOENIX. ARIZONA 85072-2034 192-00393-JGH/TDS/OAJ July 11, 1988 U. S. Nuclear Regulatory Commission NRC Document Control Desk Washington, D.C. 20555

Subject:

Palo Verde Nuclear Generating Station (PVNGS)

Unit 1 Docket No. STN 50-528 (License No. NPF-41)

Special Report 1-SR-88-005 File: 88-020-404 Attached please find Special Report 1-SR-88-005 prepared and submitted pursuant to Emergency Plan Implementing Procedure -03. This report discusses a NOTIFICATION OF UNUSUAL EVENT due to a fire in the Unit 1 Auxiliary Transformer.

If you have any questions, please contact T. D. Shriver, Compliance Manager at (602) 393-2521.

Very tru y yours, yA J. G. Haynes Vice President Nuclear Production JGH/TDS/DAJ/kj Attachment cc: D. B. Karner (all w/a)

J. B. Martin T. J. Polich E. A. Licitra A. C. Gehr INPO Records Center R. T. Milstead C. F. Tedford F. L. Russo R. Godbehere R. Colson 8807f 8024'807f f "-'J R @DOCK 05000gg8 PNU

t Palo Verde Nuclear Generating Station Unit 1 Notification of Unusual Event Docket No. 50-528 License No. NPF-41 Special Report No. 1-SR-88-005 This Special Report is being provided pursuant to Emergency Plan Implementing Procedure (EPIP)-03 to report the declaration of a Notification of Unusual Event (NUE) for Palo Verde Unit 1. The NUE was declared pursuant to EPIP-02 as a result of a fire lasting longer than 10 minutes.

At approximately 1208 HST Palo Verde Unit 1 was operating in Mode 1 (POWER OPERATION) at approximately 100 percent power when a fire occurred in the Unit Auxiliary Transformer. The fire caused a loss of non-class 1E AC power which resulted in the Reactor Coolant Pumps (RCP's) being deenergized. The loss of power to the RCP's resulted in a reactor trip. All safety systems performed as designed. The Reactor was cooled via natural circulation following the loss of forced circulation. At approximately 1215 MST, an NUE was declared pursuant to EPIP-02 as a result of the fire in the Auxiliary Transformer. At approximately 1221 HST, the fire in the Auxiliary Transformer was extinguished and the NUE terminated.

At approximately 1303 HST, Operations personnel attempted to restore off-site power to a non-class 1E bus (IE-NAN-S02) in order to start RCP's. When the bus was energized, a second fire started. It was also recognized at this time that the degraded electrical conditions present as a result of the fire in the Auxiliary Transformer resulted in a condition wherein the NUE should not have been terminated. Therefore the NUE was re-declared at approximately 1303 HST (concurrent with the second fire). The fire in the non-class 1E bus was extinguished at approximately 1322 HST; however, Unit 1 remained in the NUE due to the degraded electrical conditions.

Throughout the event, the plant remained stable utilizing natural circulation to remove decay heat via the steam generators. The transient did not result in any challenges to fission product barriers, or result in any releases of radioactive materials.

After appropriate verifications had been made that a problem did not exist with the other non-class 1E bus (1E-NAN-S01) which supplies power to two of four RCP's, off-site power was restored to lE-NAN-S01 at approximately 1749 MST. As a conservative measure, Palo Verde management decided to remain in the NUE until an RCP was started restoring forced circulation. At approximately 0033 HST on July 7, 1988 RCP lA was started. At approximately 0102 HST the NUE was terminated. The duration of the NUE was approximately 13 hours1.50463e-4 days <br />0.00361 hours <br />2.149471e-5 weeks <br />4.9465e-6 months <br />.

The event continues to be evaluated, and a Licensee Event Report will be submitted within 30 days of the event to further describe this occurrence.