ML13330B132
| ML13330B132 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 11/05/1986 |
| From: | Novak T Office of Nuclear Reactor Regulation |
| To: | Baskin K Southern California Edison Co |
| References | |
| TAC-63297 NUDOCS 8611110481 | |
| Download: ML13330B132 (5) | |
Text
Docket No.:
50-206 Mr. Kenneth P. Baskin, Vice President Nuclear Engineering Safety and Licensing Department Southern California Edison Company 2244 Walnut Grove Avenue P.O. Box 800 Rosemead, California 91770
Dear Mr. Baskin:
Reference:
Letter dated October 14, 1986, M. 0. Medford (SCE) to G. E. Lear (NRC)
Re:
San Onofre Nuclear Generating Station, Unit 1 (SONGS-1)
In the referenced letter, Southern California Edison Company reported its intention to make significant changes to two commitments previously made to the NRC.
In submittals dated April 8, 1986 and May 1, 1986 you committed to implement a modification to enhance the availability of the second source of offsite power at SONGS-1. However, your October 14, 1986 letter stated that the results of a cost-benefit study had determined that the installation of an additional immediate access source of offsite power could not be justified based on the minimal improvements in safety which it would provide. The NRC staff approval for facility restart after the November 21, 1985 loss-of-offsite power/water hammer event considered your implementation of this long-term plant improvement. Thus, the staff will evaluate your new position before determining whether or not it is acceptable for long-term operation.
Our review of this issue is ongoing.
You also stated in the Enclosure to the referenced letter that studies had concluded that the addition of new feedwater pumps and the dedication of the existing pumps to the safety injection function had likewise been determined not to be cost beneficial.
You committed to submit a comprehensive report on this issue to the NRC staff by November 1986.
8611110481 861105 PDR ADOCK 05000206 P
~18 On September 3, 1981, both trains of the SONGS-1 safety injection system were found to be inoperable due to the common-mode failure of switchover valves HV-851 A and B. In response to these failures, Southern California Edison's submittal of October 16, 1981 detailed a three-phase program to resolve the issue. Phase 1 of the program consisted of interim modifications including valve cavity venting and trip and restart of the feedwater pumps to reduce the differential pressure across the valves during the switchover operation.
Phase 2 consisted of intermediate-term replacement of valves HV-851 A and B, HV-852 A and B, HV-853 A and B, and HV-854 A and B with new valves designed such that cavity venting and trip/restart of the feedwater pumps was not required. Phase 3 consisted of an evaluation of the unique SONGS-1 safety injection system to determine if a major long-term redesign was warranted.
The NRC Safety Evaluation dated November 5, 1981 allowed restart of the facility in accordance with your proposed program and schedules. On September 28, 1982 you informed the NRC staff of the decision to pursue the Phase 3 redesign by adding a set of new feedwater pumps, thus allowing the current feedwater/safety injection pumps to be dedicated to the safety injection function. Consequently, you cancelled the order for the Phase 2 replacement valves. The installation of the new feedwater pumps was incorporated into your proposed Integrated Living Schedule for implementation during the Cycle 10 outage (now expected in early 1988).
By letter dated March 29, 1984, the NRC approved this implementation schedule for long-term safety injection upgrades.
The NRC staff has determined that your October 14, 1986 submittal, which states that a dedicated safety injection system is not cost-beneficial, is a significant departure from the long-term commitments found acceptable by the staff when your facility was allowed to restart in 1981.
Please ensure that your November 1986 submittal adequately addresses this i'ssue.
Sincerely, Original signed by Thomas M. Novak, Acting Director Division of PWR Licensing-A
- SEE PREVIOUS CONCURRENCE Office:
PM/PAD#1 PD/PAD#1 RSB AD/PWR-A PWR-A Surname: *RDudley
- GLear
- CBerlinger
- ERossi XF7V Date:
11/03/86 11/03/86 11/04/86 11/04/86 1//786
-2 On September 3, 1981, both trains of the SONGS-1 safety injection system were found to be inoperable due to the common-mode failure of switchover valves HV-851 A and B. In response to these failures, Southern California Edis6on's submittal of October 16, 1981 detailed a three-phase program to resolve the issue. Phase 1 of the program consisted of interim modificatio including valve cavity venting and trip and restart of the feedwater p ps to reduce the differential pressure across the valves during the switcho r operation.
Phase 2 consisted of intermediate-term replacement of va es HV-851 A and B, HV-852 A and B, HV-853 A and B, and HV-854 A and B wi new valves designed such that cavity venting and trip/restart of the fe water pumps was not required. Phase 3 consisted of an evaluation of te unique SONGS-1 safety injection system to determine if a major long-te redesign was warranted.
The NRC Safety Evaluation dated November 5, 81 allowed restart of the facility in accordance with your proposed p ogram and schedules. On September 28, 1982 you informed the NRC s ff of the decision to pursue the Phase 3 redesign by adding a set of new eedwater pumps, thus allowing the current feedwater/safety injection pum to be dedicated to the safety injection function. Consequently, yo cancelled the order for the Phase 2 replacement valves. The installatio of the new feedwater pumps was incorporated into your proposed In grated Living Schedule for implementation during the Cycle 10 outage (now e ected in early 1988).
By letter dated March 29, 1984, the NRC approved this implementation schedule for long-term safety injection upgrades.
The NRC staff has determined hat your October 14, 1986 submittal, which states that a dedicated saf y injection system is not cost-beneficial, is a significant departure from the long-term commitments found acceptable by the staff when your facility as allowed to restart in 1981.
Thus, the staff cannot accept your new 1 ng-term position unless a thorough analysis of and justification for the r liability of your safety injection system is provided for our review. Plea e ensure that your November 1986 submittal adequately addresses these issu s.
Sincerely, Thomas M. Novak, Acting Director Division of PWR Licensing-A Office:
PPRSB WR-A Surname: RDudley Gear CBerlinger ERossi TNovak Date:
1/ /86 1/
/86 C
/
/86 10/ /786 10/
/86
Mr. Kenneth P. Baskin San Onofre Nuclear Generating Southern California Edison Company Station, Unit No. 1 cc Charles R. Kocher, Assistant Joseph 0. Ward, Chief General Counsel Radiological Health Branch James Beoletto, Esquire State Department of Health Southern California Edison Company Services Post Office Box 800 714 P Street, Office Bldg. 8 Rosemead, California 91770 Sacramento, California 95814 David R. Pigott Mr. Hans Kaspar, Executive Director Orrick, Herrington & Sutcliffe Marine Review Committee, Inc.
600 Montgomery Street 531 Encinitas Boulevard, Suite 105 San Francisco, California 94111 Encinitas, California 92024 Mr. Stephen B. Allman Ann C. Vasques, Chief San Diego Gas & Electric Company Radiological Programs Division P. 0. Box 1831 Governor's Office of Emergency Svcs.
San Diego, California 92112 State of California 2800 Meadowview Road Sacramento, CA 95832 Resident Inspector/San Onofre NPS c/o U.S. NRC P. 0. Box 4329 San Clemente, California 92672 Mayor City of San Clemente San Clemente, California 92672 Chairman Board of Supervisors County of San Diego San Diego, California 92101 Director Energy Facilities Siting Division Energy Resources Conservation &
Development Commission 1516 - 9th Street Sacramento, California 95814 Regional Administrator, Region V U.S. Nuclear Regulatory Commission 1450 Maria Lane Walnut Creek, California 94596
OV 5 1986 Distribution Copies:
Docket Files NRC PDR Local PDR PAD#1 r/f PAD#1 p/f TNovak, Actg. DD NThompson, DHFT OGC-Bethesda Eordan BGrimes JPartlow GLear PShuttleworth RDudley ACRS (10)
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