05000361/LER-1982-099, Forwards LER 82-099/01T-0.Detailed Event Analysis Submitted

Forwards LER 82-099/01T-0.Detailed Event Analysis Submitted

ML20063P303
Person / Time
Site:	San Onofre
Issue date:	09/27/1982
From:	Ray H SOUTHERN CALIFORNIA EDISON CO.
To:	Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
Shared Package
ML20063P304	List: 05000361/LER-1982-099, Forwards LER 82-099/01T-0.Detailed Event Analysis Submitted 05000361/LER-1982-099-01, /01T-0:on 820913,Train a Control Room Emergency Air Cleanup Sys Failed to Start After Receiving Spurious Toxic Gas Isolation Signal.Caused by Improper Positioning of Kirk Key on Breaker 2BO418 of Fan E418
References
NUDOCS 8210130269
Download: ML20063P303 (2)

LER-1982-099, Forwards LER 82-099/01T-0.Detailed Event Analysis Submitted

Event date:
Report date:
3611982099R00 - NRC Website

text

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j' N.B. RAY TELEPHONE September 27, 1982 U. S. Nuclear Regulatory Commission Office of Inspection and Enforcement Region V 1450 Maria Lane, Suite 210 Walnut Creek, California 94596-5368 Attention:

Mr. R. H. Engelken, Regional Administrator

Dear Sir:

Subject: Docket No. 50-361 14-day Follow-up Report Licensee Event Report No.82-099 San Onofre Nuclear Generating Station, Unit 2

Reference:

Letter, H.B. Ray (SCE) to R.H. Engel ken (NRC),

dated September 14, 1982 The referenced letter provided you with confirmation of our prompt notification of your of fice of a reportable occurrence involving Limiting Condition for Operations (LCO's) 3.7.5 and 3.0.3 on the Control Room Emergency Air Cleanup System (CREACUS).

Pursuant to Technical Specification 6.9.1.12.b, this letter provides the required follow-up report and completed Licensee Event Report (LER) form for this occurrence.

On September 13, 1982 at 1213, while in Mode 2, a spurious Toxic Gas isolation signal on Train A CREACUS occurred. Train A of the CREACUS did not start automatically nor could it be started manually. Similarly, attempts to start Train B manually were not successful and, at 1230, having exceeded the limits of LCO 3.7.5, Section 3.0.3 of the Technical Specification became governing, allowing one hour before a shutdown /cooldown was required.

An investigation revealed that the failure of Train A to start was caused by the kirk key on breaker 2B0418 of fan E418 which was positioned half-way toward its normally closed position, consequently, Train A could not be energized.

Operability of Train A was established at 1302 by repositioning the kirk key in the breaker to its locked closed position. The 42 minute period of inoperability of both CREACUS trains was within the time constraint oi LCO 3.0.3 and plant cooldown was not initiated.

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R. H. Engelken September 27, 1982 Inoperability of Train B was ' attributable to damper 2HV9703 which would not position properly. Operability of Train B was established on September 13, 1982 at 1350 by continual cycling of this isolation damper. A specific cause could not be established, _the, damper worked properly.during the cycling and, therefore, no further corrective measures are planned.

With regard to the Train A problem, additional corrective measures

' included a revision of Operating Instruction S023-3-2.27 to direct operator!s attention to proper kirk key positioning. Further, we are evaluating the feasibility of installing indicating lights to assure positive kirk key positioning. No schedule for these measures has yet been established.

.No event requiring CREACUS operation occurred during the time both trains were Inoperable and, hence, publIc health and safety were not affected.

If there are any questions regarding the above, please contact me.

Sincerely,

/b

/

Enclosure:

LER 82-099 cc:

A. E. Chaf fee (US NRC Resident inspector San Onofre Unit 2)

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