ML20154K984

Forwards Final Rev to License Change Application 127.Reason for Change Expanded to Describe Design in Greater Detail & to Address Relevance of Previously Issued Guidance on Availability of Component Cooling Water for Reactor Pump

ML20154K984
Person / Time
Site:	Trojan File:Portland General Electric icon.png
Issue date:	03/05/1986
From:	Withers B PORTLAND GENERAL ELECTRIC CO.
To:	Varga S Office of Nuclear Reactor Regulation
References
TAC-60017, NUDOCS 8603110365
Download: ML20154K984 (2)

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- um P ernald Gerier-d MW 1

E Rut D. Wms Vce Presdxt March 5, 1986-Trojan Nuclear Plant Docket 50-344 License NPF-1 Director of Nuclear Reactor Regulation ATTN: Mr. Steven A. Varga Director, PWR-A Project Directorate No. 3 U.S. Nuclear Regulatory Connaission Washington DC 20555

Dear Sir:

License Change Application 127 Pursuant to our previous discussions concerning License Change Application (LCA) 127, attached you will find our final agreed-upon revision to this LCA. The " Reason for Change" has been expanded to: (1) describe the Trojan design in greater detail, and (2) address the relevance of previously issued NRC and Westinghouse guidance on the subject of availability of component cooling water for the reactor coolant pumps.

Sincerely,

^^

A Bart D. Withers Vice President Nuclear Attachment c: Mr. Lynn Frank, Director State of Oregon Department of Energy Mr. Michael J. Sykes i Chairman of County Conunissioners

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8603110365 860305 PDR ADOCK 05000344 P PDR 121 SW Earrco 94e. Fteard %n 97204

e LCA 127 Revision 1 REASON FOR CHANGE Surveillance Requirement 4.7.3.1.c presently requires operability of automatic CCW valves to be demonstrated by ". . . . a safety injection test signal". However, the automatic CCW valves operate upon receipt of a containment isolation signal, not a safety injection signal. It can be seen from FSAR Figure 7.2-1 (Sheet 8 of 16) that a safety injection signal will initiate Containment isolation. Specifically, either a safety injection signal or a manually initiated Containment isolation signal will result in a Containment isolation signal which closes those valves in systems penetrating the Containment which are not necessary for accident mitigation, including the CCW valves. The Containment isolation signal is distinctly different from the safety injection signal.

Generic Letter 83-10d, " Resolution of TMI Action Item II.K.3.5, ' Automatic Trip of Reactor Coolant Pumps'", suggested that for some accidents, it might be advantageous to keep the reactor coolant pumps (RCPs) operating and that the final determination should be left to the licensee. PCE reviewed the NRC evaluation, participated in the Westinghouse Owners Group analysis effort, and determined that an automatic trip of RCPs for Trojan was not desirable. Guidance was provided to the operators in the Emergency Operating Procedures under which conditions the RCPs should be tripped and which they should be left running. PGE responded to the NRC Generic Letter by a letter dated April 22, 1983 (B. D. Withers to D. G. Eisenhut).

Subsequently, PGE's site-specific evaluation determined that, under certain conditions in which the RCPs should remain in operation, CCW to the RCPs would be isolated by a Containment isolation signal. Generic Letter 83-10d indicates that if cooling water for RCPs is terminated by Containment isolation, it should be assured that cooling water can be immediately restored. Standard Review Plan (SRP) Section 9.2.2 also acknowledges the importance of maintaining cooling water to the RCPs without relying on operator action. As a result, modifications were made to the Containment isolation signal to valves MO-3294, MO-3296, MO-3300, and MO-3320 causing them to automatically isolate only upon receipt of a containment isolation signal in coincidence with a low CCW surge tank level or upon receipt of a high-high containment pressure signal. This modification is consistent with the Westinghouse Standard NSSS Design Criteria which specifies that CCW should be terminated on a containment Isolation Phase B (high-high Containment pressure) signal.

Since Technical Specification 4.7.3.1.c was already in need of clarifica-tion, it was determined to make this specific change to reflect the modification. No change to the actual surveillance requirement, valves to be tested, or frequency is being made. Only clarification as to the actual source of isolation of certain CCW valves is being made.

CAZ/kal 5718k.286