ML13331A313
| ML13331A313 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 03/16/1989 |
| From: | Nandy F SOUTHERN CALIFORNIA EDISON CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| IEB-88-010, IEB-88-10, NUDOCS 8903210107 | |
| Download: ML13331A313 (3) | |
Text
Southern California Edison Company.
P. 0. BOX 800 2244 WALNUT GROVE AVENUE ROSEMEAD. CALIFORNIA 91770 F
R.NANDY TELEPHONE MANAGER OF NUCLEAR LICENSING March 16, 1989 (818) 302-1896 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555 Gentlemen:
Subject:
Docket No. 50-206 NRC Bulletin 88-10, "Non-Conforming Molded Case Circuit Breakers" San Onofre Nuclear Generating Station Unit 1 The purpose of this letter is to notify the NRC of a situation at San Onofre Unit 1 that is not explicitly addressed in NRC Bulletin 88-10. Although SCE will apply the requirements of the bulletin to this non-addressed condition, SCE considers that NRC management should be notified of this situation prior to receipt of our complete Bulletin 88-10 report. A description follows.
By letter dated November 27, 1988, the NRC issued Bulletin 88-10, "Non-Conforming Molded Case Circuit Breakers."
The bulletin requires, among other things, that if a circuit breaker (CB) installed in safety related applications must be replaced, it must be replaced with a CB that conforms with the requirements of Action Item 7 of the bulletin. Item 7 requires that breakers installed in the plant in safety related applications after August 1, 1988 must be:
a) Manufactured and procured from a circuit breaker manufacturer (CBM) under a 10 CFR 50, Appendix B program; or b) Procured from a CBM or others with verifiable traceability to the CBM, in compliance with applicable industry standards, and upgraded to safety related by the licensee or others using an acceptable dedication program.
If CB's that would satisfy the requirements of Action Item 7 are not available, the bulletin allows for the use of CB's that have been tested in accordance with Attachment I of the bulletin. However, the bulletin only specifically addresses testing of warehouse breakers as an option to the requirements of Action Item 7 if more than 80% of CB's purchased after August 1, 1988 are verifiable as traceable to the CBM (Action 3) or as replacements for installed CB's that cannot be traced to a CBM (Action 5).
6
'~.I
Document Control Desk
-2 The bulletin does not specifically address the use of non-traceable warehouse CB's that pass the testing requirements of Attachment I if less than 80% of the warehouse spares are traceable. Additionally, the bulletin requires that CB's installed after August 1, 1988 meet only the requirements specified in Action 7. However, the bulletin does not specifically address the addition to existing busses of CB's that are no longer available from the CBM or replacement of installed, obsolete CB's replaced for reasons (e.g., damaged breakers) other than the result of Actions 3 and 5 of the bulletin.
San Onofre Unit 1 has identified the need to replace 5 breakers in safety related applications prior to restart following the current outage. An additional 4 breakers are needed to replace other in plant spares used during this outage. These breakers are Westinghouse "E" series breakers and are no longer in production.
SCE has twelve spare "E" series Westinghouse breakers in warehouse stock that are not traceable to the CBM and were purchased during 1977-1978 as non-safety related. SCE has already determined that San Onofre has less than 80% CB traceability. SCE plans to test these breakers in accordance with the requirements of NRC Bulletin 88-10, Attachment I, upgrade these breakers to safety related using our existing upgrade procedure and install them in Unit 1. This situation is not explicitly covered in NRC Butteti n88-T-i n-that the-replacementCB'swere manufactured prior to August 1, 1983. However, SCE believes the approach tobe consistent with the replacement of breakers allowed by Actions 3 and 5 of the bulletin. SCE also considers it prudent to inform the NRC of the following related information regarding these breakers:
- 1) The replacement breakers were manufactured and purchased as non-safety related.
- 2) They may have been purchased from one of the known suppliers of refurbished breakers. (These replacement breakers are a riveted design which makes tampering much more difficult and less likely.)
- 3) Substitute breakers identified by the original equipment manufacturer do not fit existing panels.
For the situation described above, SCE considers our most prudent option to be replacement of the subject breakers from existing warehouse stock that have been tested in accordance with the requirements of Attachment I to the bulletin. SCE believes that the testing prescribed in Attachment I of the bulletin in conjunction with the engineering evaluation required by SCE's stock upgrade program more than adequately addresses the concerns of the NRC relative to CB performance and is considered acceptable. This letter is being submitted for information purposes.
Document Control Desk
-3 SCE will provide the NRC with the required response to NRC Bulletin 88-10 by April 1, 1989 under separate cover.
If you have any questions or comments, please contact me.
Very truly your cc: J. B. Martin, Regional Administrator, NRC Region V F. R. Huey, NRC Senior Resident Inspector, San Onofre Units 1, 2 and 3