05000361/LER-1982-087, Forwards LER 82-087/03L-0.Detailed Event Analysis Submitted

Forwards LER 82-087/03L-0.Detailed Event Analysis Submitted

ML20065B218
Person / Time
Site:	San Onofre
Issue date:	09/03/1982
From:	Ray H SOUTHERN CALIFORNIA EDISON CO.
To:	Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
Shared Package
ML20065B220	List: 05000361/LER-1982-087, Forwards LER 82-087/03L-0.Detailed Event Analysis Submitted 05000361/LER-1982-087-03, /03L-0:on 820806,atmospheric Dump Valve 2HV-8419 Failed Closed & Declared Inoperable During Performance of Low Power Physics Testing.Caused by Broken Spool Piece at Junction of Air & Nitrogen Backup Lines.Piece Replaced
References
NUDOCS 8209140300
Download: ML20065B218 (2)

LER-1982-087, Forwards LER 82-087/03L-0.Detailed Event Analysis Submitted

Event date:
Report date:
3611982087R00 - NRC Website

text

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Yn Southern California Edison Company

$ 15 m,

S AN ONOFRE NUC L E AR GENER A TING S T A TION

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P.O. BOE 125 S A N C L EME N T E, C A LIFO R NI A 92672 s u 0o N i, A N September 3, 1982 j,'?,'[,",,'l, G.

U. S. Nuclear Regulatory Commission Office of inspection and Enforcement Region V 1450 Maria Lane, Suite 210 Walnut Creek, Cali f ornia 9 4596-5368 Attention:

fir. R. H. Engelken, Regional Administrator w

Dear Sir:

Subject: Docket No. 50-361 30-Day Report Licensee Event Report No.82-087 San Onof re Nuclear Generating Station, Unit 2 This submittal is in accordance with the reporting requ: ements of Section 6.9.1.13b of Appendix A to Facil ity Operating License NPF-10.

It describes a reportable condition involving Limiting Condition for Operation (LCO) 3.6.3 associated with containmeni isolation valves.

On August 6, 1982, while in Mode 2 during performance of low power physics testing, atmosphere dump valve 2HV-8419 was discovered to have failed closed.

The valve was declared inoperable at 1720 and LCO 3.6.3 Action Statement c was initiated.

As required by this Action Statement, the penetration was isolated by securing manual block valve 8"-231-C-129 in the closed position.

Subsequent investigation revealed that the valve failed due to a broken spool piece at the junction of the instrument air and the nitrogen backup lines. These lines provide motive force for valve modulation.

The valve was returned to service at 2040 on August 6, 1982 after replacing the spool piece and recharging the nitrogen backup tank.

Since this line is not subject to substantial stress from system operation, the failure is presumed to have occurred due to nearby construction activity and is considered an isolated occurrence.

Further corrective action is not deemed necessary.

8209140300 820903 PDR ADOCK 05000361 S

PDR

~[E-24 EA -316

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a R. H. EngeIken September 3, 1982 Since the valve failed in the conservative direction as designed, there was no impact on health and safety of piant personnel or the publIc.

Sincerely, fd

/

Enclosure:

LER 82-087 cc:

A. E. Chaf fee (USNRC Resident inspector, San Onof re Unit 2)

U. S. Nuclear Regulatory Commission Office of Inspection and Enforcement U. S. Nuclear Regulatory Commission Office of Management Information and Program Control Institute of Nuclear Power Operations