ML13317B327
| ML13317B327 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 03/29/1991 |
| From: | Nandy F SOUTHERN CALIFORNIA EDISON CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| REF-GTECI-099, REF-GTECI-NI, TASK-099, TASK-99, TASK-OR GL-88-17, GL-90-04, GL-90-4, NUDOCS 9104010379 | |
| Download: ML13317B327 (2) | |
Text
Southern California Edison Company 23 PARKER STREET IRVINE, CALIFORNIA 92718 F. R. NANDY TELEPHONE MANAGER, NUCLEAR LICENSING March 29, 1991 (714) 454-4504 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555 Gentlemen:
Subject:
Docket No. 50-206 Generic Safety Issue No. 99, RCS/RHR Suction Line Valve Interlock on PWRs San Onofre Nuclear Generating Station, Unit 1 This letter clarifies the applicability of generic safety issue (GSI) No. 99 to SONGS 1. GSI No. 99 addresses the inadvertent automatic closure of interlocked suction valves in the residual heat removal (RHR) system of PWRs when the RHR system is in use. Recent correspondence from the NRC implied that modifications to the RCS/RHR interlock system were to be implemented on SONGS 1 during the recent refueling outage. As discussed with our NRC project manager, Mr. John Bradfute, this is not the case.
Your letter of November 6, 1990, summarizing the status of various GSIs at SONGS 1, 2 and 3, identified GSI No. 99 as an open issue requiring certain modifications to be completed during the Cycle 11 refueling outage.
- However, unlike other PWRs, SONGS 1 does not have an automatic interlock feature associated with its RHR system. Consequently this concern of GSI No. 99 is not applicable to SONGS 1 and the issue should be considered closed.
The reference to plant modifications made in the NRC's letter was based on information provided in SCE's letter dated June 27, 1990. Our letter provided information on the status of various GSIs in response to an NRC request (Generic Letter (GL) 90-04, dated April 25, 1990).
The description of GSI No. 99 provided in the NRC's request indicated that the interlock issue was broadened to include concerns associated with mid-loop operation of the plant.
The description further indicated that these concerns were covered by GL 88-17, "Loss of Decay Heat Removal."
The information provided in our June 27, 1990 letter referred to certain Cycle 11 modifications to satisfy GL 88-17.
All of these modifications have been completed. However, no modifications col
-9104010379 910329 PDR ADOCK 05000206 PDR
.Document Control Desk
-2 were required as a result of the RHR valves interlock issue. The reference to the modifications related to GL 88-17 in our June 27, 1990 letter, was intended only for completeness of the status description.
If you have any questions, please call me.
Very truly yours, cc:
George Kalman, NRC Project Manager, San Onofre Unit 1 J. B. Martin, Regional Administrator, NRC Region V C. W. Caldwell, NRC Senior Resident Inspector, San Onofre Units 1, 2 & 3 C. D. Townsend, NRC Resident Inspector, San Onofre Unit 1