ML20154K381

Submits Listed Estimates for Evaluating Cost of Generic Ltr 88-03, Steam Binding of Auxiliary Feedwater Pumps

ML20154K381
Person / Time
Site:	Trojan File:Portland General Electric icon.png
Issue date:	05/24/1988
From:	Cockfield D PORTLAND GENERAL ELECTRIC CO.
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
GL-88-03, GL-88-3, IEB-85-001, IEB-85-1, TAC-67284, NUDOCS 8805310018
Download: ML20154K381 (3)

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- PortlandGeneralElectricCompany r - E David W. Cockfield Vice President. Nuclear May 24, 1988 Trojan Nuclear Plant Docket 50-344 Licenso NPF-1 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555

Dear Sir:

Generic Letter 88-03; Resolution of Generic Safety Issuo 93, "Steam Binding of Auxiliary Foodwater Pumps" The subject generic letter requested confirmation that the f u t ,,tng recommendations of U.S. Nuclear Regulatory Commission (NRC) Office of Inspection and Enforcement (IE) Bulletin 85-01 (October 29, 1985) are being followed and maintained.

1. Maintain procedures to monitor fluid conditions within the Auxiliary Feedwater (AFW) system each shift during times when the system is required to be operable. This monitoring should ensure that fluid temperature at the AFW pump discharge is maintained at about ambient levels.

2. Maintain procedures for recognizing steam binding and for restoring the AFW system to operable status, should steam binding occur.

On February 28, 1986, portland General Electric (PGE) responded to IE Bulletin 85-01 with the following list of actions being taken to precludo steam binding of the auxiliary feedwater ( AFW) pumps at the Trojan Nuclear Plant:

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1. The AFW System operating procedure was revised to require that the safety-related AFW pump dischargo piping be chocked for elevated temperatures approximately 5 minutes after each time a pump is stopped.

2. Operations personnel were trained on the possible causes and symptoms l of back-leakage through the AFW pumps, and on the aforementioned proceduro chaago.

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3. A routine operating test procedure was revised to require that pump discharge piping temperatures be monitored at least once each shift, and to prescribe follow-up actions in the event that elevated temperatures are identified.

4. The 18-month test procedure for the AFW System was revised to require performance of a full-system-pressure leak test for the second-off AFW pump discharge check valves.

5. Contact surface thermometers were installed on the AFW pump discharge piping during the 1986 refueling outage. The thermometers provide a means of identifying and recording the piping temperatures on a once-per-shift basis, with further evaluation required if elevated temperatures are found.

PGE's response to the IE Bulletin also indicated that, should steam binding of both safety-related AFW trains occur, the electric motor-driven AFW pump could be relied upon to supply foodwater to the steam generators. The electric AFW pump utilizes separate suction and discharge piping.

A monitoring program to prevent steam binding of the AFW pumps, which follows the recommendations of IE Bulletin 85-01, is being maintained at the Trojan Nuclear Plant. System temperatures (from the contaci thermometers) are recorded once each shift such that increasing trends, which would indicate possible check valve leakage, can be identified. If temperatures are found to exceed 120*F, the affected AFW pump is required to be vented. Operating procedures also require the discharge temperature of each AFW pump to be checked approximately 5 minutes after the pump is stoppod. These monitoring requirements address the IE Bulletin 85-01 recommendations summarized in Generic Letter 88-03, and are deemed adequate to recognize AFW System check valve back-leakage and prevent steam binding of the AFW pumps.

Concerning Item 4 of the February 28, 1986 PGE to NRC letter, the system pressure leak test was performed during the 1987 refueling outage. Because of the test configuration, the results were inconclusive. The testing periodicity fer check valves in the main and auxiliary feodwater systems has now been adjusted for consistency with In-Service Testing (IST) Program requirements. As noted in PGE's letter to the NRC of April 15, 1988, the four first-off AFW check valves from the main feedwater lines and the four msin feedwater check valves in the branch lines to the steam generators are now ocing leak tested, or disassembled for inspection, every two years.

I Pordand General MCoritxviy Document Control Desk May 24, 1988 Page 3 As requested in Generic Letter 88-03 the following estimates are provided for evaluating the cost of the Generic Letter.

1. Estimated staff time to perform the requested confirmation and any needed following actions: 1 man week

2. Staff time to prepare requested documentation: 1 man week, PGE will be pleased to provide additional information on this matter if needed.

Sincerely, r

l D. W. Cockfiel

! Vice Presiden Nuclear l

I Attachment Subscribed and sworn to before me this 24th day of May 1938.

fit ede T '~t Notary Public of Oregoni My Commission Expires: 4V drcef f /((/

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