ML20206P242

Special Rept:On 981219,number 12 Hydrogen Monitoring Sys (Hms) Was Declared Inoperable When Operators Closed Valve 201.2-601.Caused by Indeterminate Failure of Valve 201.2-71. Supplemental Rept Will Be Submitted After Valve Is Repaired

ML20206P242
Person / Time
Site:	Nine Mile Point
Issue date:	12/30/1998
From:	Terry C NIAGARA MOHAWK POWER CORP.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NMP1L-1397, NUDOCS 9901110046
Download: ML20206P242 (2)

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NiagarahMohawk' Phone: 315.349.7263 Me$ident Fax; 315.349.4753 Nuclear Safety and Assessment and Support t

December 30,1998 NMPIL 1397 m

~ U. S. Nuclear Regulatory Commission

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- Attn: Document Control Desk Washington, DC 20555 RE: Nine Mile Point Unit 1 -

Docket No. 50-220 DPR-63

Subject:

Special Report Gentlemen:

In accordance with Nine Mile Point Unit 1 (NMPI) Technical Specification (TS) Table 3.6.11-2, " Accident Monitoring Instrumentation," Action Statement 4.a, Niagara Mohawk "

Power Corporation (NMPC) is submitting the following Special Report concerning the

inoperability of #12 Containment Hydrogen Monitoring System (HMS).

i Desedation of Event. $

On December 19,1998, at approximately 1515 hours0.0175 days <br />0.421 hours <br />0.0025 weeks <br />5.764575e-4 months <br />, with the reactor mode switch in the h

"RUN" position during normal operation, NMP1 operators declared the #12 HMS inoperable when they closed valve 201.2-601, which isolated #12 HMS. Check valve 201.2-71 failed reverse flow testing, which required operators to close valve 201.2-601 per TS 3.3.4,

" Primary Containment Isolation Valves."

raun of Event -

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Maintenance personnel have not yet determined the cause of the failure of check valve 201.2-

71. Maintenance personnel are developing a plan to repair the check valve including determination of the cause of failure. A supplement to this Special Report will be submitted after the valve is repaired. _

9901110046 991230 .

, Lycoming, New Yod 13093-0063

• www.nimo.com

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l Cometive Acdons Corrective actions will be developed when the cause of check valve 201.2-71 failure is determined and will be provided in a supplement to this Special Report, l

Very truly yours, j 1

l Carl D. Terry Vice President Nuclear Safety Assessment and Support CDT/GJG/ kap l

xc: Mr. H. J. Miller, Regional Administrator, Region I Mr. G. K. Hunegs, Senior Resident Inspector 1 Records Management j l

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