ML20128Q326

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Responds to Requesting That Plant File Written Jco & Engineering Analysis for Equipment That Did Not Meet EQ Requirements,Iaw GL 91-18
ML20128Q326
Person / Time
Site: Maine Yankee
Issue date: 10/03/1996
From: Shirley Ann Jackson, The Chairman
NRC COMMISSION (OCM)
To: Christine K, Christine P
AFFILIATION NOT ASSIGNED
Shared Package
ML20128Q330 List:
References
GL-91-18, NUDOCS 9610210032
Download: ML20128Q326 (2)


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October 3, 1996 CHAmMAN Kris L. Christine and Peter C. Christine P.O. Box 12 Alna, Maine 04535

Dear Ms. & Mr. Christine:

I am responding to your letter dated August 3,1996, in which you asked whether Maine Yankee would file a written justification for continued operation (JCO) and an engineering analysis for equipment that did not meet the environmental qualification (EQ) requirements, in accordance with Generic Letter (GL) 91-18, "Information to Licensees Regarding The NRC Inspection Manual Sections on Resolution of Degraded and Nonconforming Conditions and on Operability," before receiving NRC's approval for restart.

In fact, Maine Yankee did prepare a JC0 for those items which could not be relocated to avoid submersion after a loss of coolant accident (LOCA).

The JC0 included, referenced, and/or referred to engineering analyses, which, like the JC0, are retained at the plant.

Formal NRC approval was not required for Maine Yankee 1

to restart the plant; however, NRC understood that the utility would not proceed to restart until both Maine Yankee and the NRC were satisfied that the plant was ready to resume operation.

The NRC reviewed Maine Yankee's actions prior to restart and concluded that they were ap'propriate and are consistent with NRC guidance in GL 91-18 and GL 88-07, " Modified Enforcement Policy Relating to 10 CFR 50.49, ' Environmental Qualification of Electrical Equipment 1

Important to Safety for Nuclear Power Plants.'"

l Generic Letter 91-18 indicates that environmental qualification issues are addressed using GL 88-07, dated April 7, 1988.

Generic Letter 88-07 does not l

require the licensee to file a JC0 with the NRC when unqualified equipment is i

identified; however, it notes that written justification for continued l

operation is to be available for NRC review.

Maine Yankee and the NRC staff conducted independent reviews of tne recently identified problem prior to restart. As a result of the Independent Safety Assessment Team's questions pertaining to electric components important to l

safety that could become submerged following a postulated LOCA, Maine Yankee j

in July 1996 performed a walkdown of electric equipment requiring EQ inside the reactor containment and identified 30 items that could become fully or partially submerged post-LOCA. Most of the items, which included such equipment as Rosemount level transmitters and pigtails (cable), valve Dp l

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2 position switches and pigtails, and Rockbestos cable, are for post-accident monitoring (Regulatory Guide 1.97, " Instrumentation for Light-Water-Cooled Nuclear Power Plants to Assess Plant and Environs Conditions During and Following an Accident," items). About one half of the 30 items are in the steam generator level indication instrument loops. The remaining items are

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used for valve position indication.

As a result, Maine Yankee relocated some i

instruments and developed a JC0 in accordance with GL 88-07 for the others.

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i An NRC inspection was conducted from August 6 to August 9, 1996, to review Maine Yankee's corrective actions in response to the electric equipment submergence issue and Maine Yankee's JC0 for those items that would remain j

submerged after a LOCA for which EQ could not be established.

The inspection i

concluded that Maine Yankee had properly provided a justification in Maine Yankee document DBS No.96-044, " Design Basis Screen to Assess the Results of Submergence on EQ Components on the -2 ft. Elevation of the Reactor Containment and Review the Impact of their Submergence on Nuclear Safety,"

Revision 1, dated August 8, 1996.

This justification was reviewed by the NRC during the inspection and was determined to be acceptable.

If you have any additional questions in this matter, please contact Mr. Richard J. Conte, Chief, Reactor Projects Branch No. 5 in our Region I office at (610) 337-5183.

Sincerely, Shirley Ann Jackson