ML20005E488

Responds to Generic Ltr 89-10 Re motor-operated Valve Testing & Surveillance.Listed Actions Will Be Performed in Order to Meet Recommendations of Generic Ltr

ML20005E488
Person / Time
Site:	Prairie Island
Issue date:	12/28/1989
From:	Parker T NORTHERN STATES POWER CO.
To:	Office of Nuclear Reactor Regulation
References
GL-89-10, NUDOCS 9001080011
Download: ML20005E488 (2)

Text

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414 Nicollet Mall Minneapolis. Minnesota 554011927 Telephone (612) 330 5500,

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' December 28, 1989 3

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Director of Nuclear Reactor Regulation

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U,S Nuclear Regulatory Commission

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'RIE ISLAND NUCLEAR GENERATING PIANT

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Dock,t.Nos. 50 282 License Nos. DPR-42 50-306 DPR-60 s

Response to NRC' Generic Letter 89-10 Motor-operated Valve Testinn and Surveillance

'The purpose of this-1'etter is to respond to Generic Letter 89 10.

lThe Prairiri Island motor cperated valve (MOV) program will implement the

- recommendations of Generic Letter 89-10 within the schedule proposed by 4

.tho' letter. The. majority of the recommendations already exist in the program, but some. refinements will.need to be made.

T The major, difference between the. program implemented for Bulletin 85-03 and the upgraded program recommended by Generic Letter 89-10 is a change

.in diagnosticLequipment. The new equipment can' accurately determine stem thrust:for each MOV in both the open and close directions, thus' eliminating a large unknown factor relating to stem friction.

In-house procedures are being. developed and technicians are being trained on the use of this diagnostic equipment.

To meet the recommendations of Generic Letter 89-10, the following will be, performed:

1 a.

The design basis for each MOV is being established and documented.

The' methodology used to determira maximum differential pressures j

' is ide,- Mcal to that used for Bulletin 85 03.

The method is very consern cive, often specifying pressures that are not testable.

Some refineinent may be needed for these extreme cases.

This design basis reviev will be conipleted within the one year specified in the letter.

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Northem States Power Company December 28, 1989 Page 2 b.-

ALreview and update of the Prairie Island Motor Operated Valve Program, Procedure H5, will be performed.

The program was initially established in response to Bulletin 85 03 and it has subsequently _been expanded to cover all safety related MOVs. The program needs strengthening in the areas of differential pressure testing criteria and post maintenance testing with enhanced diagnostics.

These program changes will be completed within the one year specified in the Generic Letter.

c.

Degraded voltage conditions need to be addressed in a two-stage process due to the installation of two new safeguards diesel generators at Prairie Island. The first stage, used to address the interim period until the new diesel generators are installed, will use a worst case enveloping approach to assure MOV performance.

The second stage, which will address the completed

' diesel generator configuration, will evaluate each MOV individually to assure MOV performance.

The first stage will be completed within the one year specified in the letter.

The second stage will be completed in parallel with'the diesel generator schedule (less than 5 years).

d.

Differential pressure testing will be performed to the extent practicabic.

It is recognized that a small group of valves cannot safely be tested at full design basis conditions. Justification for'not testing these valves as well as alternate verification of l

the correct switch settings will be documented.

e.

Overall implementation of the items associated with design basis reviews, analyses, verifications, tests and inspections will be completed within the 5-year time period stipulated in the Generic Letter. MOVs will be prioritized by their safety

significance and scheduled accordingly.

Please contact us if y..

require additional information related to the Generic Letter.

Thomas M Parker Manager Nuclear Support Services J,

c: Regional Administrator - Region III, NRC Senior Resident Inspector, NRC NRR Project Manager, NRC C Charnoff

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