ML13310B063
| ML13310B063 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 10/31/1983 |
| From: | Krieger R SOUTHERN CALIFORNIA EDISON CO. |
| To: | Crutchfield D Office of Nuclear Reactor Regulation |
| References | |
| RTR-NUREG-0737, RTR-NUREG-737, TASK-02-01.C, TASK-2-1.C, TASK-3.D.3.4, TASK-RR, TASK-TM NUDOCS 8311090051 | |
| Download: ML13310B063 (2) | |
Text
Southern California Edison Company P.0 BOX 800 2244 WALNUT GROVE AVENUE ROSEMEAD, CALIFORNIA 91770 October 31, 1983 Director, Office of Nuclear Reactor Regulation Attention: Mr. 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-l.C, Potential Hazards Due to Nearby Transportation, Institutional, Industrial and Military Facilities San Onofre Nuclear Generating Station Unit 1
References:
- 1. Letter, W. A. Paulson, NRC, to R. Dietch, SCE, SEP Topic II-l.C, Potential Hazards Due to Nearby Transportation, Institutional, Industrial and Military Facilities, May 3, 1983
- 3. Letter, K. P. Baskin, SCE, to D. M. Crutchfield, NRC, Clarification of TMI Action Plan Requirements, April 13, 1981 Reference 1 provided the staff's final evaluation of SEP Topic II-1.C for San Onofre Nuclear Generating Station, Unit 1. The evaluation concluded that we met the current criteria with regard to risk to the plant from (1) nearby industrial facilities, (2) nearby military facilities (except for munitions shipments), (3) commercial shipping lines at sea, and (4) three nearby gas pipe lines. The evaluation also concluded that the probability of explosions due to accidents involving materials on both I-5 and the AT&SF railroad is about 4.5 x 10-6 per year, which exceeds current criteria of SRP 2.2.3, and the probability of a toxic gas cloud being swept into the control room air vent exceeds current criteria. Reference 1 requested that the shipment frequencies in the second paragraph of Section 5.2.2 be updated to assure that assumptions made in the calculations of the probability of explosions due to accidents on I-5 and the AT&SF railroad are accurate. It is the purpose of this letter to respond to the open items in the above discussed final evaluation for input to the Integrated Assessment.
9311090051 831031 1
PDR ADOCK 05000206 I
P PDR
Mr. D.
October 31, 1983 The calculated probability of explosions, due to accidents on 1-5 and the AT&SF railroad, exceeding 0.5 psi overpressure is 4.58 x 10-6 per year.
This was provided to you in our report "Analysis of Hazards for Rail and Highway Transportation Routes near the San Onofre Nuclear Generating Station Unit 1," submitted as an enclosure to Reference 2. As explicitly stated in that report and briefly stated in Reference 1, the analysis contains many conservatisms which allow the judgement that the actual probability is substantially lower than 4.58 x 10-6 per year. Accordingly, no modifications are planned.
The probability of a toxic gas cloud being swept into the control room exceeds current criteria.
However., this issue has been addressed by NUREG-0737, Item III.D.3.4 -
Control Room Habitability. As previously stated in Reference 3, the modifications to respond to this issue will be determined during the Integrated Assessment. Accordingly, they will be scheduled as part of the Integrated Living Schedule.
The request to revise the information in the second paragraph of Section 5.2.2 of the evaluation will be complied with when the information becomes available. The information is currently requested by the NRC as part of the Safety Evaluation Report related to the operation of San Onofre Nuclear Generating Station, Units 2 and 3, NUREG-0712, Supplement No. 2, Section 2.2.2 and required by San Onofre Units 2 and 3, Appendix A Technical Specification 6.9.1.14. The reporting frequency is identified to be once every 3 years, which requires a report to the NRC on the San Onofre Units 2 and 3 docket by February 17, 1985. Accordingly, when that information is made available to comply with the San Onofre Units 2 and 3 requirement, we will provide it to you on Docket No. 50-206 in compliance with the above discussed request.
Based upon the above discussion, we consider this topic resolved for San Onofre Nuclear Generating Station, Unit 1. If you have any questions, please let me know.
Very truly yours, R. W. Krieger Supervising Engineer San Onofre Unit 1 Licensing