ML20112G747
| ML20112G747 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 03/04/1985 |
| From: | Mangan C NIAGARA MOHAWK POWER CORP. |
| To: | Starostecki R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| (55(E)-85-03), (55(E)-85-3), (NMP2L-0356), (NMP2L-356), NMPEL-356), NUDOCS 8504010233 | |
| Download: ML20112G747 (2) | |
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a N3Mtine NIAGARA 000MAWK POWER CORPORAT10N/300 ERIE BOULEVARD WEST SYRACUSE. N.Y.13202/ TELEPHONE (315) 4741511 March 4,1985 (NMP2L 0356)
Mr. R. W. Starostecki, Director U. S. Nuclear Regulatory Comission Region I Division of Project and Resident Programs 631 Park Avenue King of Prussia, PA 19406 Re: Nine Mile Point - Unit 2 Docket No. 50-410
Dear Mr. Starostecki:
Enclosed is a final report, in accordance with 10CFR50.55(e), for the problem concerning ~ Category I motor operators inside a nonseismic structure.
This problem was reported via tel-con to W. Lazarus of your staff on January 31, 1985.
Very truly yours, M
C. V. Man n Vice President Nuclear Engineering and Licensing CVM/GG:cla (0797H) xc: Director of Inspection and Enforcement U. S. Nuclear Regulatory Commission Washington, DC 20555 R. A. Gram, NRC Resident Inspector Project File (2) 8504010233 850304 PDR ADOCK 05000410 1
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.r NIAGARA M0 HAWK POWER CORPORATION NINE MILE POINT - UNIT 2 DOCKET NO. 50-410 Final Report Concerning Category I Motor Operators Inside a Nonseismic Structure (55(e)-85-03)
Description of the Problem The problem concerns the Quality Assurance Category I motor operators, 2SWP*MOV30A and B and 2SWP*MOV77A and B located at the 285 foot elevation and 261 foot elevation, respectively.
The screenwell building roof is Quality Assurance Category II.
In addition, there is a nonseismic block wall near operators for valves 2SWP*MOV77A and B.
Analysis of Safety Implications The failure of the non-Category I structures could cause damage to the valve operators, thus rendering the safety-related valves inoperable.
Valves MOV77A and B are norm 111y closed.
If the normal flow path through the two screenbays is blocked, tio level switches in the service water pump bay will open these ~ valves to allow the required flow to bypass the travelling screens.
MOV30A and B are two motor-operated, rectangular rotary gate valves, arranged in series and normally open, located between the north shaft and the intake bay.
If the normal discharge tunnel, a non-Category I structure, becomes
' unavailable following a seismic event, these gates are designed to close and isolate the north intake shaft from the intake bay.
The north intake shaft and tunnel would then carry the discharge back to Lake Ontario.
Damage to the valve operators would prevent the valves / service water system from performing their safety functions.
Therefore, had thi s condition remained uncorrected, it could have adversely affected the safety of operations of the plant.
Corrective Action A housing will be provided to prevent any damage to the subject valve operators from the failure of non-Category I structures.
The design of the housing will be issued for construction by April 15, 1985