05000206/LER-1981-026, Forwards LER 81-026/01T-0.Detailed Event Analysis Submitted

Forwards LER 81-026/01T-0.Detailed Event Analysis Submitted

ML20033A308
Person / Time
Site:	San Onofre
Issue date:	11/16/1981
From:	Ray H SOUTHERN CALIFORNIA EDISON CO.
To:	Engeleken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML20033A309	List: 05000206/LER-1981-026, Forwards LER 81-026/01T-0.Detailed Event Analysis Submitted 05000206/LER-1981-026-01, /01T-0:on 811102 Vol of Water in Refueling Water Storage Tank Fell Below Tech Spec When recirculation-to- Condenser Valve Water CV-36 Failed to Close,Allowing 15,000 Gallons of Refueling to Be Pumped Into Condenser
References
NUDOCS 8111250158
Download: ML20033A308 (2)

LER-1981-026, Forwards LER 81-026/01T-0.Detailed Event Analysis Submitted

Event date:
Report date:
2061981026R00 - NRC Website

text

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a REC 8VED IGC Southern California Edison Compang g 79 p p p WE S AN ONOFRE NUCLE AR GENER ATING ST A TION P.O. BOX 128 S AN C LEMENTE. C ALIFORNI A 92672 Q#]

l H. B. R AY TELEPMo t November 16, 1981

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Office of Inspecticn and Enforcement NOV24 4

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Region V 1450 Maria Lane, Suite 210 i yM'jprela Walnut Creek, California 94596-5368 4/.

Attention: Mr. R. H. Engelken, Director

/(f f-N DOCKET No. 50-206 SAN ON0FRE-UNIT 1

Dear Sir:

This letter provides the follow up report describing a reportable occurrence involving a minimum flow valve in the Safety Injection System. Submittal is in accordance with the reporting requirements stipulated in Section 5.9.2 of Appendix A to the Provisional Operating License DPR-13. This occurrence was ' initially reported by our letter of November 2,1981.

In conjunction with the testing of the Safety Injection Hydraulic valves several cycles of Safety Injection initiation were performed. While in Mooe three during the final Hot Safety Injection System Test, CV-36, a valve in the recirculation line to the condenser, failed to close, resulting in 15,000 gallons of refueling water being pumped into the condenser.

As a result, the volume of water in the refu? ling water storage tank fell below technical specification requirements. Volume was restored within two hours. We are continuing evaluation of the effect on Safety Injection System performance had this failure occurred during an actual LOCA.

The valve is operated by a pneumatic cylinder. A Safety Injection signal overrides the normal minimum flow controller by actuating solenoid dump valves. One of these solenoid valves was found to have its pneumatic connections made to the wrong ports. This was verified from the manufactur-ers connection diagrams; and confirmed from the connections to properly operating valves of the same type in the plant. This situation had previously resulted in a slow closing response and, finally a complete failure to close. The pneumatic lines were reconnected properly, and CV-36 was tested satisfactorily prior to plant startup.

gfY 8111250158 8111 ~

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l U. S. Nuclear Regulatory Commission If you should require additional information, please contact me.

Sincerely,

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Enclosure: Licensee Event Report 81-026 cc:

U. S. Nuclear Regulatory Commission Office of Inspection and Enforcement U. S. Nuclear Regulatory Commission Office of Management Information & Program Control (MIPC)

Institute of Nuclear Power Operations L. F. Miller (USNRC San Onofre Unit 1 Resident Inspector)