ML20028E093

Forwards LER 82-020/03L-0.Detailed Event Analysis Encl

ML20028E093
Person / Time
Site:	Oconee
Issue date:	01/13/1983
From:	Tucker H DUKE POWER CO.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML20028E094	List: ML20028E093 ML20028E099
References
NUDOCS 8301200341
Download: ML20028E093 (3)

Text

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DUKE POWER GOMPAhT P.O. DOX 33180 CHAMLOTTE, N.C. 28242 II AL II. TUC4ER . TELEPHONE 4'NE PRESIDwNT ) oMNI

.m u. - *== January 13, 1983 ._

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Mr. James P. O'Reilly, Regional Administrator Q N U. S. Nuclear Regulatory Commission .

Region 11 3

101 Marietta Street, Suite 3100 ,7 Atlanta, Georgia 30303 ,.

Re: Oconee Nuclear Station Docket No. 50-269

Dear Mr. O'Reilly:

Please find attached Reportable Occurrence Report R0-269/82-20. This report is submitted pursuant to Oconee Nuclear Station Technical Specification 6.6.2.1.b(2) which concerns operation in a degraded mode permitted by a limiting condition for operation, and describes an incident which is considered to be of no significance with respect to its effect on the health and safety of the public.

Very truly yours,

$. M l,lfg Hal B. Tucker 1

JCP/php

! Attachment cc: Document Control Desk U. S. Nuclear Regulatory Commission Washington, D. C. 20555 Mr. W. T. Orders NRC Resident Inspector j Oconee Nuclear Station INP0 Records Center Suite 1500 1100 Circle 75 Parkway Atlanta, Georgia 30339 i

Mr. E. L. Conner, Jr.

Office of Nuclear Reactor Regulation 1

U. S. Nuclear Regulatory Commission

, Washington, D. C. 20555 1

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Duke Power Company Oconee Nuclear Station Report Number: R0-269/82-20 Report Date: January 13, 1983 Occurrence Date: December 14, 1982 Facility: Oconee Unit 1, Seneca, South Carolina Identification of Occurrence: The Turbine Driven Emergency Feedwater Pump and the "A" Motor Driven Emergency Feedwater Pump were both technically inoperable for less than one minute.

Conditions Prior to Occurrence: 100% FP Description of Occurrence:

On December 15, 1982, while maintenance work was being performed, the turbine driven emergency feedwater pump (EFWP) lost automatic start capability when f power was lost to its auxiliary oil pump. Power was lost to the auxiliary  !

oil pump while the IPA and IFB 125/250 volt d.c. (direct current) system batteries were being returned to service (power to the oil pump is supplied by this system). At this same time, the 1A motor driven EFWP waa in manual for testing purposes.

Therefore, at 0936 hours0.0108 days <br />0.26 hours <br />0.00155 weeks <br />3.56148e-4 months <br /> both the Unit 1 turbine driven and the 1A motor driven EFWPs were incapable of automatic actuation for approximately 60 seconds.

Since neither pump was capable of automatic actuation for this time period, they are considered to have been inoperable. This placed Unit 1 in a degraded mode per Technical Specification 3.4 and is reportable per Technical Specifica-tion 6.6.2.lb(2).

Apparent Cause of Occurrence:

The cause of this occurrence was due to defective procedures. Newly rewritten restoration to service procedures were being performed for the first time for both the Unit 1 PA and PB batteries. Due to wording that was unclear, and instructions for steps that were later found to be unnecessary, the PB tie breakers were opened. This caused power loss to the PN and N buses; thus, the auxiliary oil pump to the turbine driven EFWP lost power.

Analysis of Occurrence:

The 1A motor driven and turbine driven EFWPs were considered to be inoperable only because they could not automatically start. Both pumps were inoperable at once for approximately 60 seconds. The likelihood of needing EFW during any given 60 second period with the unit at power is low. The Control Room Operators knew that the 1A motor driven EFWP was in manual and could have put the pump back in automatic had emergency feedwater been needed. Also, the IB

EFWP was in automatic during this incident so it would have automatically started. If necest.ary, the turbine driven EFWP could havs been started at the pump. The hea".th and safety of the public were not jeopardized.

Corrective Action:

The immediate corrective action was to reclose the tie breakers between the IPB and 2PB batteries which restored power to the Unit 1 PN bus and N bus within 60 seconds. The person involved was counseled on the interpretation.

of the procedure. A change is planned for this procedure which should prevent recurrence of this event.

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