ML20214C336
| ML20214C336 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 11/12/1986 |
| From: | Berry K CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| References | |
| IEB-86-003, IEB-86-3, NUDOCS 8611210069 | |
| Download: ML20214C336 (3) | |
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5 h clear Licensing messars -ra General Offees: 1945 West Parnall Road. Jackson, MI 49201. (517) 788-1636 November 12, 1986 James G Keppler, Administrator Region III US Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, IL 60137 DOCKET 50-255 - LICENSE DPR PALISADES PLANT -
RESPONSE TO IE BULLETIN 86-03 Potential Failure of Multiple ECCS Pumps Due to Single Failure of Air-Operated Valve in Minimum Flow Recirculation Line described a design deficiency at the Point Beach Plant related to the failure mode of two series air-operated valves in a common recirculation header for safety injection pumps. Required Action Item 3 of the Bulletin requested a written report identifying whether or not this problem exists at Palisades, and if so, justification for cortinued operation and a description of any short-term modifications required.
Our review of the Palisades ECCS has determined that Palisades does not have this problem. Palisades utilizes a minimum flow header with two series isolation valves to the refueling water tank that close after recirculation actuation. This flow header, as originally construct ad and operated through Fuel Cycle One, had the isolation valve fail closed on loss of power. During review of Fuel Cycle Two, the minimum flow valves were identified as a source of " undesirable function" failure.
Changes described in our letter from Ralph B Sewell to R A Purple of NRC dated April 7, 1976, were implemented prior to Cycle Two startup (May 9, 1976).
Presently the valves which are each powered from a separate bus fail open on j
loss of power. The valves fail "as is" on loss of air.
i During the recent Safety System Functional Inspection (exit interview on October 24, 1986) reviewers had a concern that these valves (CV-3027 and CV-3056) which are supplied by a single safety-grade high-pressure air source
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might not close after recirculation actuation due to a single failure of the 8611210069 861112 ~
PDR ADOCK 05000255 G
PDR NOV 17 W OC1186-0182-NLO2 II
4 Administrator, Region III 2
Palisades Plant Response to IEB 86-03 November 12, 1986 air system. Although this concern is still open, the postulated situation does not cause failure of the ECCS.
- :aw- -,
Kenneth W Berry Director, Nuclear Licensing CC Director, Office of Nuclear Reactor Regulation Director, Office of Inspection and Enforcement NRC Resident Inspector - Palisades l
OC1186-0182-NLO2 1
Administrator, Region III 3
Palisades Plant Response to IEB 86-03 November 12, 1986 CONSUMERS POWER COMPANY Palisades Plant Docket 50-255 - License DPR-20 RESPONSE TO IE BULLETIN At the request of the Commission and pursuant to the Atomic Energy Act of 1954 and the Energy Reorganization Act of 1974, as amended, and the Commission's Rule and Regulations thereunder, Consumers Power Company submits our response to IE Bulletin 86-03 dated October 8, 1986, entitled, Potential Failure of Multiple ECCS Pumps Due to Single Failure of Air-Operated Valve in Minimum Flow Recirculation Line."
Consumers Power Company's response is dated November 12, 1986.
CONSUMERS POWER COMPANY By-
'~7/
/u saA F V Buckman, Vice Pres Nuclear Operations Sworn and subscribed to before me this 12th day of November, 1986.
12 ALLA Elaine E Buehrer,TNotary Public Jackson County My commission expires October 31, 1989 OC1186-0182-NLO2
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