ML13324A839

Forwards Rev 1 to 01-0310-1435, San Onofre Generating Station Unit 1,10CFR50,App R,Section Iii.G Compliance Evaluation. Rev Incorporates Evaluation of Circuits for Which Field Walkdown Required

ML13324A839
Person / Time
Site:	San Onofre
Issue date:	04/23/1986
From:	Medford M Southern California Edison Co
To:	Lear G Office of Nuclear Reactor Regulation
Shared Package
ML13324A840	List: ML13324A839
References
TAC-64883 NUDOCS 8604250211
Download: ML13324A839 (2)

Text

49 7/7Z Southern California Edison Company P. 0. BOX 800 2244 WALNUT GROVE AVENUE ROSEMEAD, CALIFORNIA 91770 M.O.MEDFORD TELEPHONE MANAGER, NUCLEAR LICENSING (818) 302-1749 April 23, 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 Fire Protection Program Review San Onofre Nuclear Generating Station Unit 1 By letters to the Commission, dated October 4 and December 31, 1985, SCE committed to provide additional information regarding application of the safe shutdown requirements of section III.G of Appendix R to 10 CFR 50 to San Onofre Unit 1. In addition, as a result of meetings and telephone discussions between SCE and the NRC staff further information was requested.

The purpose of this letter is to provide the above described information, as requested by the NRC. Accordingly, provided as Enclosure I are the affected pages of Revision 1 to the III.G Compliance Evaluation.

Revision 1 incorporates the evaluation of circuits for which a field walkdown was required. The incorporation of these circuits does not impact the conclusions of the III.6 Evaluation, Revision 0, submitted October 4, 1985.

Also, the results of the high impedance fault analysis for 120 volt AC electrical systems has been completed and determined not to impact the III.G analysis.

The evaluation of the charging pump suction valve spurious operation continues under review. Any modifications identified to be necessary in order to mitigate the consequences of spurious charging pump suction valve operation will be complete prior to return to service and will be designed in compliance with 10 CFR 50 Appendix R Section III.6 requirements.

The III.G Compliance Evaluation and the affected fire area/zone evaluations will be updated to reflect this modification and the dedicated shutdown system upon completion of installation.

As requested by the NRC staff during the February 7, 1986 meeting, provided as Enclosure 2 is a copy of the dedicated shutdown repairs list.

These repairs may be necessary to achieve cold shutdown subsequent to an Appendix R fire in a fire zone requiring the use of the dedicated shutdown system. Since these repairs are necessary only for achieving cold shutdown, adequate time and manpower to perform these repairs will be available.

Procedures and operator training for the alternative and dedicated shutdown systems will be completed prior to return to service.

I 8604250211 860423 PDR ADOCK 05000206 F

PDR

Mr. G.

April 23, 1986 In response to an NRC reviewer's question, it is noted that the High-Low pressure interfaces identified in SCE's submittal dated June 30, 1982 were clarified and resolved in the October 4, 1985 submittal.

The resolution of these items are evaluated in Revision 0, of the 10 CFR 50, Appendix R, Section III.G Compliance Evaluation for San Onofre Unit 1 provided as an enclosure to that submittal.

Provided as Enclosure 3 is Revision 1 of the Request for Exemption from Section III.G.3 10 CFR 50 Appendix R for Containment Fire Area 1-CO.-(--10)-l.

Revision 1 incorporates a field design change resulting from difficulty encountered in routing Rockbestos cable for circuits TE-402A, TE-412A and TE-422A. Although this design change does not affect the Request for Exemption for this fire area, Revision 1 is provided for completeness.

Provided as Enclosures 4, 5 and 6 are Fire Area Evaluation 1-AB-14-35, Revision 0, Fire Zone Evaluation 1-YD-14-4D, Revision 1 and Request for Exemption from Section III.G.3 10 CFR 50 Appendix R for Yard Area Fire Zone 1-YD-14-4D, Revision 2 respectively. This information is provided to reflect a change in the routing of the cables for the train 1 charging pump G-8B and its associated support equipment. During field rerouting of these cables, it was identified that routing through fire zone 4C was not possible.

Therefore the cables were routed through fire zone 40.

The change in routing has been determined to not impact III.G compliance and Enclosures 4, 5 and 6 are provided for completeness.

The schedule for compliance with the III.G requirements is defined in NRC letter dated May 10, 1982, which granted the schedular exemption SCE requested. Based on this exemption, the date for completion of all modifications not associated with the Dedicated Shutdown System is startup from this outage.

The Dedicated Shutdown Equipment is required to be completed based on a calendar schedule which indicates a compliance date of April 30, 1986.

However, it is our understanding that the NRC has in the past considered the compliance date to occur at the end of an outage when the due date falls during the outage. Therefore, the compliance date for the Dedicated Shutdown System is also startup from this outage. All modifications, procedures and training associated with III.G compliance will therefore be completed prior to entering MODE 2 or compensatory measures in accordance with our proposed Technical Specifications will be in place.

If you have any questions, or desire additional information, please contact me.

Very truly yours, Enclosures cc:

F. R. Huey, Senior Resident Inspector