ML20117N435
| ML20117N435 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 04/30/1985 |
| From: | Mangan C NIAGARA MOHAWK POWER CORP. |
| To: | Starostecki R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| (55(E)-84-09), (55(E)-84-9), (NMP2L-0394), (NMP2L-394), NUDOCS 8505170530 | |
| Download: ML20117N435 (2) | |
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NIAGARA 000lfAWK POWER CORPORAT10N/300 ERIE BOULEVARD WEST, SYRACUSE. N.Y.13202/ TELEPHONE (315) 4741511 i
April 30, 1985 (NMP2L0394)
Mr. R. W. Starostecki, Director U.S. Nuclear Regulatory Commission Region,I Division of Reactor Projects 631 Park Avenue King of Prussia 19406 Re: Nine Mile Point - Unit 2 Docket No. 50410
Dear Mr. Starosteckt:
Enclosed is a final report, in accordance with 10CFR50.55(e), for the problem concerning a hydraulic trantient for pump restart in the service water sys tem.
This problem was reported via tel-con to S. Collins of your staff on February 15, 1984.
An interim report was submitted via our letter dated March 14,1984 Very truly yours, M
C. V. Manga Vice President Nuclear Engineering and Licensing i
CVM/GG/cla i
xc: Director of Inspection and Enforcement 4
U.S. Nuclear Regulatory Commission Washington, DC 20555 R. A. Gramm, NRC Senior Resident Inspector l
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a NIAGARA MOHAWK POWER CORPORATION NINE MILE POINT - UNIT 2 DOCKET NO. 50-410 Final Report for a Problem Concerning Hydraulic Transient for Pump Restart (55(e) 09)
Description of the Problem The hydraulic transient for pump restart was not considered in the service water piping system analysis.
As a result of problems in some operating plants, this condition was initially addressed by the Nuclear Regulatory Comission in NUREG 0582.
Analysis of Safety Implications A detailed investigation of the effects of a pump restart on pipe and pipe support stresses for the service water system was not performed.
It is possible that a pump restart could increase the pipe or support stresses to a magnitude high enough to render the system inoperable.
Therefore, this condition could have adversely affected the safety of operations of the plant.
Corrective Actions The loadings from the hydraulic transient for pump restart are being included in the pipe stress analysis and the pipe support reconciliation effort for the affected Category I service water piping system.
It should be noted that the project as-built stress reconciliation program takes into account all changes in design / layout since the initial piping system analysis.
Therefore, if this analysis indicates a modification is required, it may not be possible to identify the specific change or changes that caused the need fcr the modification.
The stress reconciliation prograr will be complettM by January 20, 1986.