ML13324A458
| ML13324A458 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 10/26/1984 |
| From: | Medford M SOUTHERN CALIFORNIA EDISON CO. |
| To: | Eisenhut D Office of Nuclear Reactor Regulation |
| References | |
| GL-84-15, TAC-55900, NUDOCS 8410300229 | |
| Download: ML13324A458 (3) | |
Text
Southern California Edison Company P. 0.
BOX 800 2244 WALNUT GROVE AVENUE ROSEMEAD. CALIFORNIA 91770 M.O. MEDFORD TELEPHONE MANAGER, NUCLEAR LICENSING October 26, 1984 (213) 5 72.1749 Director, Office of Nuclear Reactor Regulation Attention:
Mr. 0. G. Eisenhut, Director Division of Licensing U. S. Nuclear Regulatory Commission Washington, D.C.
20555 Gentlemen:
Subject:
Docket No. 50-206 NRC Generic Letter 84-15, Proposed Staff Actions to Improve and Maintain Diesel Generator Reliability San Onofre Nuclear Generating Station Unit 1
References:
A. NRC Generic Letter 84-15, dated July 2, 1984, Proposed Staff Actions to Improve and Maintain Diesel Generator Reliability B. Enclosure 28 to letter M. 0. Medford (SCE) to D. M. Crutchfield (NRC) dated June 29, 1984, Return to Service Requirements Regarding Transamerica Delaval Emergency Diesel Generators C. Letter, M. 0. Medford (SCE) to D. G. Elsenhut (NRC), dated October 1, 1984, San Onofre Nuclear Generating Station, Units 2 and 3 By Reference A, the NRC requested information from all licensees of operating reactors regarding the reliability of their emergency diesel generators. Specifically, the items covered by Reference A were the following:
- 1.
Licensees were requested to describe their current program to avoid cold fast start surveillance testing, or their intended actions to reduce cold fast start surveillance testing of diesel generators.
- 2.
Licensees were requested to furnish the current reliability data for each diesel generator at their plant(s), based on surveillance test data.
- 3.
Licensees were requested to describe their program, if any, for attaining and maintaining a reliability goal for their diesel generators and to compare it with the model program contained in Reference A.
8410300229 841026 PDR ADOCK 05000206 P
Mr. D..G. Eisenhut
-2 The information below provides our responses to Items 1, 2 and 3 above, relative to San Onofre Nuclear Generating Station, Unit 1.
- 1. Reduction in Number of Cold Fast Start Surveillance Tests for Diesel Generators The cooling water system for each of the San Onofre Unit 1 emergency diesel engines is designed such that it circulates heated water (140oF to 170 0F) drawn from a jacket water standpipe by means of a keep warm pump to keep the engine warm even when the engine is not running. In this way, stress and wear of the engine parts due to fast surveillance starts from ambient conditions are minimized.
For the monthly surveillance tests, the manufacturer's recommended preparatory actions, which include a brief prelubrication of the engine moving parts, are performed, in accordance with plant procedure S01-10-1.
In addition, neither the San Onofre Unit 1 Technical Specifications nor the plant procedures require testing of the diesel generators upon emergency core cooling equipment being declared inoperable. For these reasons, the concerns expressed by this item are not applicable to San Onofre Unit 1.
- 2. Diesel Generator Reliability Data San Onofre Unit 1 does not currently maintain a record of valid demands and failures in the manner outlined in Regulatory Guide 1.108, nor does it maintain a yearly data report for each diesel generator's reliability. However, chronological test data collected for the seven year period from April 1977 through April 1, 1984, in Reference B, indicate:
For diesel generator #1, 372 starts were performed with 5 malfunctions For diesel generator #2, 387 starts were performed with 4 malfunctions.
Reference B describes each malfunction, the date it occurred and the associated corrective action.
- 3.
Diesel Generator Reliability Improvement Program A reliability improvement program comparable to that described in NRC Generic Letter 84-15 presently does not exist for the San Onofre Unit 1 diesel generators.
However, all diesel engine surveillance tests and their successes or failures are tracked. In keeping with good operation and maintenance practices, analyses of failures and determinations of root causes of failures are carried out and documented in Station Incident reports. We will develop and implement a formal reliability improvement program for the San Onofre Unit 1 diesel generators.
The program is currently scheduled to be developed by April 1, 1985. At that time a comparison with the NRC's Generic Letter 84-15 will be prepared and forwarded to the NRC.
Mr. D.. G. Eisenhut
-3 If you have any questions concerning the above information, please let me know.
Subscribed on this =2b' day of 1984.
Respectfully submitted, SOUTHERN CALIFORNIA EDISON COMPANY By:
4r M. 0. Medford Manager of Nuc ear Licensing, Subscribed and sworn to before me thjs
~(A~Z day of OFFICIAL SEAL Lo
)C SALLY SEBO Notary Public i ar'd for the County of NOARYUeCCALIFORNIA Los Angeles, State of California My 0mm. expires APR 14, 1986 My Commission Expires:
cc:
USNRC Document Control Desk, Washington, D.C. 20555 A. E. Chaffee (USNRC Resident Inspector, San Onofre Units 1, 2 and 3)
J. B. Martin (Regional Administrator, Region V)