ML13324A824
| ML13324A824 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 03/26/1986 |
| From: | Medford M Southern California Edison Co |
| To: | Lear G Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8603310121 | |
| Download: ML13324A824 (2) | |
Text
Southem California Edison Company P. 0. BOX 800 2244 WALNUT GROVE AVENUE ROSEMEAD. CALIFORNIA 91770 M.O.MEDFORD TELEPHONE MANAGER, NUCLEAR LICENSING (818)302-1749 March 26, 1986 Director, Office of Nuclear Reactor Regulation Attention:
G. E. Lear, Director PWR Project Directorate No. 1 U. S. Nuclear Regulatory Commission Washington, D.C.
20555 Gentlemen:
Subject:
Docket No. 50-206 Impact of Safety Injection/Feedwater Pumps Check Valve Replacement on Amendment Application No. 132 San Onofre Nuclear Generating Station Unit 1
Reference:
Letter, Robert Dietch, SCE, to H. R. Denton, NRC, dated November 20, 1985 The referenced letter proposed changes to San Onofre Unit 1 Technical Specifications (T.S.) 4.2.3 "Safety Injection Hydraulic Valve Testing" and 4.2.1 "Safety Injection and Containment Spray System Periodic Testing." The changes would eliminate the once every 92 day surveillance of the Safety Injection System (SIS) per T.S. 4.2.3 and add a specification of an acceptable actuation time for the SIS hydraulic valves in T.S. 4.2.1.
The 92 day surveillance requirement was added following modifications to the SIS in 1981.
One of the modifications performed at that time was the addition of a hole and notch in the SI/feedwater pumps check valves. These were added to allow pressure decay in the space between the check valves and the SIS hydraulic valves once the SI/feedwater pumps had been tripped during a postulated safety injection event.
In view of actions being taken as a result of the November 21, 1985 water hammer event, the NRC Staff has questioned whether these actions will affect the bases for the proposed changes to the Technical Specifications.
The purpose of this letter is to respond to the Staff's question.
Due to the November 21, 1985 event, SCE is, among other things, replacing certain check valves in the feedwater system. Included in this replacement are the two check valves on the SI/feedwater pumps discharges.
Since the design of these check valves is essential to successful SIS operation, special attention is being given to assure the pressure relieving 83603310121 8360326 PDR ADOCK 05000206
~O S
Mr. G.
March 26, 1986 function of these valves is maintained. Therefore, NRC review and approval of the proposed Technical Specifications should not be affected by the new check valve modifications.
If there are any questions, please contact me.
Very truly yours, cc:
- 3. B. Martin, NRC Region V, Regional Administrator F. R. Huey, USNRC Senior Resident Inspector, Units 1, 2 and 3 J. 0. Ward, California Department of Health Services