ML19207C067

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Responds to IE Bulletins 79-01 & 79-01A.Informs of Electrical Equipment Unqualified for Intended Svc.Suspect Devices Are Asco Containment Isolation Solenoid Valves. Qualified Components Are on Order. Er
ML19207C067
Person / Time
Site: Pilgrim
Issue date: 08/28/1979
From: Andognini G
BOSTON EDISON CO.
To: Eisenhut D
Office of Nuclear Reactor Regulation
References
79-171, NUDOCS 7909060403
Download: ML19207C067 (2)


Text

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BOSTON EDISON COMPANY GENERAL oFFICEE B00 BOYLSTON STREET BOSTON. M ASEACNuSETTs o2199 August 28, 1979 G. CARL ANDDGNIN8 SUPERIHTENDENT NUCLE AR OPERATIONS DEPARTMENT BECo. Ltr. #79-171 Mr. D. Eisenhut, Director Division of Operating Reactors Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Co= mission Washington, DC 20555 License No. DPR-35 Docket No. 50-293 Environmental Qualification of Class IE Equipment Reporting of Uncualified Equipment

Reference:

(a) IE Bulletin 79-01 (b) IE Bulletin 79-01A

Dear Sir:

Pursuant to the reporting requirements of References (a) and (b), this letter serves to inform you of the identification of certain electrical equipment at Boston Edison's Pilgrim Station Unit #1, which, based upon the location of the equipment, has been identified as unqualified for the service intended.

'The suspect devices are ASCo solenoid valves (Model HT 8320A22) whose safety related function is to de-energize to a fail-safe state, initiating a primary containment isolation of drywell floor and equipment drain sump effluent lines.

The valves providing isolation, (AO's 70llA&B and 7017A&B) are all located out-side primary containment in the torus compartment.

Boston Edison Company has reviewed the environmental functional limitations of the currently installed solenoid valves with "ASC0" and has identified a situation where potential failure of the solenoid valve internal elastomer materials could occur. This failure would be due to the total integrated doses that are anticipated within the torus compartment following a LOCA incident. The solenoid valve, in this mechanically-failed condition, could possibly reapply instrument air to the isolation valves, causing them to open.

Continued plant operation is justified on the basis that alternate controls and isolation equipment are readily accessible to adequately isolate drvwell sump effluent lines. In addition, any leakage that might carry over prior to the implementation of alternate isolation methods would be contained in a Radiation Waste Process Building, which is designed to process the liquid waste material. Also, any resultant plant airborne activity would be immed-fately detected thereby notifying the operator of this situation. g 1

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BOSTON EDISON COMPANY t

August 28, 1979 Director Page Two Boston Edison has qualified replacement solenoid valves on order; however, due to the industry-wide demand, we do not expect delivery for approximately eight (8) weeks.

Following receipt of the qualified solenoid valves, installation will be implemented at the next scheduled plant outage. We trust that this informa-tion is responsive to the concerns outlined in References (a) and (b).

If you have any questions or comments, please do not hesitate to contact us.

Very truly yours,

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cc: Mr. Boyce H. Grier Office of Inspection and Enforcement Region I U.S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, PA 19406

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