05000270/LER-1979-009, Forwards LER 79-009/01T-0

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Forwards LER 79-009/01T-0
ML20125B703
Person / Time
Site: Oconee Duke Energy icon.png
Issue date: 12/21/1979
From: Parker W
DUKE POWER CO.
To: James O'Reilly
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML20125B706 List:
References
NUDOCS 7912270503
Download: ML20125B703 (2)


LER-2079-009, Forwards LER 79-009/01T-0
Event date:
Report date:
2702079009R00 - NRC Website

text

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' DUKE POWER COMPANY Powen Dust.nixo 422 SocTn Cauwen STazzT, Cruat.oTTE, N. C. asa4a j wrLuAu o. PA R et C R, J R

< cr aamo ~e December 21, 1979 it c -e~r *at ma 5 ca. Pamceo~ 3' 3- ac e J

-i Mr. James P. O'Reilly, Director U.S. Nuclear Regulatory Commission Region II 101 :trietta Street, Suite 3100 Atlant1. GA 30303 Re: Oconee 2 Docket No. 50-270 I

Dear Mr. O'Reilly:

Please find attached Reportable Occurrence Report R0-270/79-9. This report is sube.itted pursuant to Oconee Nuclear Station Technical Specification 6.6.2.1.a(2), which concerns operatloc with a carameter subject to a limiting cc: :1: ion for operation less conservati're than the least :enservative aspect of the 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.

i Very truly yours,

. L W William O. Parker, Jr. #

SRL/sch Attachment ec: Director, Office of Management Information and Program Control 90002;50 t 3k ["Ik

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DUKE POWER COMPANY Oconee Unit 2 Report Number: R0-270/79-9 Report Date: December 21, 1979

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Occurrence Date: December 9, 1979 cu eu m es[_bb..  ;$

Facility: Oconee 2, Seneca, South Carelina Identification of Occurrence: HPI Suction Valves Rendered Inoperable Conditions Prior to Occurrence: 99% Full Power Description of Occurrence:

On December 9, 1979, during performance of annual preventive maintenance f ar Engineered Safeguards (ES) valves, valves 2HP-24 and 2HP-25, the Oconee 2 hiah pressure injection (HPI) suction valves fren the borated water storace tank (Cis'ST) were rendered inonerable briefly. The limit switches for the equi-

. lent valves for 'cenc a 1, which was in cold shutdown, were to have been

.le aned, but the limit cwi;:S assemblies for the Ccenee _ valves, which :re

' ec md nea rby , w re i na.i"er t en t h re=cved and cleaned. Cor.tr:1 r- wr o nn; c'rserved err a:ic cesition indication, first for valve 2HP-24, and then for valve 2HP-25, and it was determined that the limit switenes fer tne vrong valves were being cleaned. Each valve was inoperable #or no more than 15 minutes, and oniv one valve was out of service ut a time. Both valves were tested to

/erify proper operation.

imiront Ca u s < r# currenc2

'lalves 2HP-24 and 21'P-25 were rendered inoperable when their limi: swit:h assemblies were inadvertently removed. The valves are located in the same general area as the equivalent Oconee 1 valves, resulting in the confusian.

Analysis of Occurrence:

Valves 2HP-24 and 2HP-25 are located in the redundant lines from the BWST providing suction for the HPI pumps. Only one valve was inoperable at a time, so the BL.'ST was always available to supply HPI suction if required. In addition, the letdcwn storaze tank was available as a source of water. Houever, Oconee Nuclear Station Technical Specification 3.3.2.5 requires that ES valves be operable when a unit's reactor coolant system is heated above 350 F. Therefore, this incident must be reported pursuant to Technical Specification 6.6.2.1.a(2),

although it is considered to be of no significance with respect to safe operation, and the health and safety of the public were not affected.

Corrective Action:

The immediate corrective action was to reinstall the valves' limit switches. The valves were then tested to verify operability. The personnel responsible for the error have been counselled and disciplined appropriately. In. order to preclude the occurrence of a similar incident, maintenance procedures will be evaluated and revised to include placing a tag on components subject te maintenance or repair whose associated electrical breakers or switches have been tag 6ed out.90 0