ML13317A688
| ML13317A688 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 10/08/1981 |
| From: | Moody W Southern California Edison Co |
| To: | Crutchfield D Office of Nuclear Reactor Regulation |
| References | |
| TASK-02-03.B1, TASK-2-3.B1, TASK-RR NUDOCS 8110150418 | |
| Download: ML13317A688 (2) | |
Text
Southern California Edison Company P. 0. BOX 800 2244 WALNUT GROVE AVENUE ROSEMEAD. CALIFORNIA 91770 W. C. MOODY TELEPHONES MANAGER, NUCLEAR LICENSING (213) 572.1817 October 8, 1981 (213) 572-1806 CT14 1981 s Director, Office of Nuclear Reactor Regulation Attention: D. M. Crutchfield, Chief Operating Reactors Branch No. 5 Division of Licensing U. S. Nuclear Regulatory Commission Washington, D.C.
20555 Gentlemen:
Subject:
Docket No. 50-206 SEP Topic II-3.B.1 San Onofre Nuclear Generating Station Unit 1 Your letter of June 12, 1981, forwarded the draft evaluation for SEP Topic II-3.B.1, Ability of Operating Plants to Cope with Design Basis Flooding. Your letter requested that we review the facts upon which the staff has based its evaluation. The results of our review as well as additional comments on your assessment are provided as an enclosure to this letter.
Delay of submittal of this information has been discussed with the NRC staff.
If you have any questions regarding the enclosed, please let me know.
Very truly yours, Enclosure 8110
Enclosure SCE Comments on SEP Topic II-3.B.1 San Onofre Unit 1
- 1. The NRC's evaluation indicates that there are no existing emergency plans for San Onofre Unit 1 that relate to flooding from external sources.
This is not correct.
Emergency instruction S01-1.6.2, Tsunami Warning, identifies actions required in the event of a tsunami.
- 2. The NRC's evaluation is based on the statement "one method of protecting a plant against postulated floods is by implementing appropriate technical specifications and emergency procedures."
While this may be true for some plants for some flooding conditions, this is not appropriate for San Onofre Unit 1. The need for or adequacy of emergency procedures or technical specifications cannot be assessed without first determining the design basis flooding conditions at the plant and evaluating the effects of such conditions on the plant.
In order to meet NRC requirements with respect to design basis flooding at San Onofre Unit 1, SCE has spent over 5 million dollars on plant modifications related to flood protection. These modifications include a wall north of the plant which diverts flood water through a diversion basin to the intake structure, curbs and grading to divert precipitation away from safety related structures and into a new yard sump, and a berm east of the plant to divert flood water away from the plant site. Without these modifications, based on the calculated design basis flood conditions, there is no technical specification or emergency procedure which could adequately protect the plant.
In view of the above considerations, the evaluation of this topic should not be completed until after completion of SEP Topics II-3.A, Hydrologic Description, 11-3.B, Flooding Potential and Protection Requirements, and III-3.A, Effects of High Water Level on Structures.