ML19210C680

Forwards LER 79-048/03L-0

ML19210C680
Person / Time
Site:	Fort Saint Vrain
Issue date:	11/09/1979
From:	Warembourg D PUBLIC SERVICE CO. OF COLORADO
To:	Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML19210C681	List: ML19210C680 ML19210C685
References
P-79269, NUDOCS 7911190421
Download: ML19210C680 (3)

Text

, 1~ public service company ce cdonde j 16805 Weld County Road 191/2, Platteville, Colorado 80651 L__d .

November 9,1979 Fort S t. Vrain-Unit No.1 P-79269 Mr. Karl V. Seyfrit, Director Nuclear Regulatory Cor=1ssion Region IV Office of Inspection and Enforcement 611 Ryan Plaza Drive Suite 1000 Arlington, Texas 76012 REF: Facility Operating License No. DPR-34 Docket No. f 0-267

Dear Mr. Seyfrit:

Enclosed please find a cupy of Reportable Occurrence Report No. 50-267/79-48/03-L-0, Final, submitted per the requirements of Ter huical Specification AC 7.5.2(b)2.

Also, please find enclosed one copy of the Licensee Event Report for Reportable Occurrence Report No. 50-26 7/ 79-48/03-L-0.

Very truly yours, Ow 4Jo -

Don Warembourg

/w Manager, Nuclear Production DW/alk cc: Director, MIPC 7

T 7 91119 " p2/

. REPORT DATE: November 9,1979 REPORTABLE OLCURRENCE 79-48 ISSUE O OCCURRENCE DATE: October 11, 1979 Page 1 of 2 FORT ST. VRAIN NUCLEAR GENERATING STATION PUBLIC SERVICE COMPANY OF COLORADO 16805 WELD COUNTY ROAD 19 1/2 PLATTEVILLE, COLORADO 80651 REPORT NO. 50-267/ 79-48/03-L-0 Final IDENTIFICATION OF OCCURRENCE:

At 0900 hours0.0104 days <br />0.25 hours <br />0.00149 weeks <br />3.4245e-4 months <br /> on October 11, 1979, with the plant operating at approximately 60% thermal power and 172 MWe, "B" station battery set was removed from ser-vice. The battery was returned to service at 0830 hours0.00961 days <br />0.231 hours <br />0.00137 weeks <br />3.15815e-4 months <br /> on October 12, 1979.

This period of time constitutes operation under a degraded mode permitted by LCO 4.6.1(e) and is reportable per Fort St. Vrain Technical Specification AC

7. 5. 2 (b) 2.

EVENT DESCRIPTION:

On September 27, 1979, persoanel performing the quarterly station battery sur-veillance observed that one of the 60 cells of "B" station battery had a low specific gravity. The bad cell did not significantly affect total battery out-put, and the battery itself remained operable. At 0900 hours0.0104 days <br />0.25 hours <br />0.00149 weeks <br />3.4245e-4 months <br /> on October 11, 1979, the battery was de-energized and removed from service in order to repair the faulty cell. During the time the battery was out of service, the second s tation battery remained operable. Attempts to charge the cell were unsuccess-ful, and it was eventually removed from the battery and shipped to the manu-facturer for repair or replacement. Engineering evaluation indicated that the battery will still meet the criteria required for operability without this cell.

The period of time for which the battery was out of service for removal of the faulty cell constitutes operation in a degraded mode permitted by LCO 4.6.l(e).

CAUSE DES CRIFrION:

The degraded mode operation referenced in this report occurred as a result of removing "B" battery from service to j umper a faulty cell. During the quarterly s urveillance , the cell was observed to have low specific gravity due to normal use over a period of time.

CORRECTIVE ACTION:

The inoperable cell was removed from the battery and sent out for repair. The battery was returned to service within the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> period allowed by LCO 4.6.1 and remains operable with the cell removed.

No further corrective action is anticipated or required. i354 356

REPORTABLE OCCURRENCE 79-48 ISSUE O Page 2 of 2 -

Prepared by: ec/w soc [/

Cathy C. Jiirsch Technical Services Technician Reviewed by: '

. W. CAhm

/ Technical Services Supervisor Reviewed by:

Frank M. Mathie Operations Manager Approved by: m h b Don Warembourg g/

Manager, Nuclear Production 1354-357