ML20084E281

AO 50-244/74-03:on 740214,containment Purge & Exhaust Dampers Failed to Maintain Leakage Rates within Specified Levels.Repairs to Dampers Will Be Completed

ML20084E281
Person / Time
Site:	Ginna
Issue date:	02/15/1974
From:	Platt C ROCHESTER GAS & ELECTRIC CORP.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20084E279	List: ML20084E273 ML20084E281
References
AO-50-244-74-03, AO-50-244-74-3, NUDOCS 8304150006
Download: ML20084E281 (1)

Text

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Mr. James P. O'Reilly, Director Directorate of Regulatory Operations

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U. S. Atomic Energy Commission 9.h 'h gD 631 Park Avenue /, ^[4 6' King of Prussia, Pennsylvania 19406  % . /

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Subject:

Abnormal Occurrence 74-3: Failure of one or more components of an engineered safety feature or plant protection system that causes or threatens to cause the feature or system to be incapable of performing its intended function.

R. E. Ginna Nuclear Power Plant, Unit No.1 Docket No. 50-244 .

Dear Mr. O'Reilly:

During a pressure decay test of the containment purge supply and exhaust damper volumes to determine leakage of the dampers, an excessive leakage rate was obtained from both the supply and exhaust test volumes.

In each case the test volume is established by two closed 48 inch diameter dampers, one inside the containment vessel and the other immed-lately outside of the containment vessel.

Pressure decay from each of the test volumes showed a pressure loss of 2 psig/ min. which is approximately 79,000 cc/ min. leakage rate from each test volume, for a total leakage rate of approximately 158,000 cc/ min.

Technical Specifications allow local leakage to be .45 Lp, which is equivalent to a volumetric rate of 17,200 cc/ min. @ 60 psig. With the test volume pressurhed with air to 60 psig, an inspection was made of the dampers insido containment. Air leakage from cach damper was audible at one location between the damper and "O" ring seat. Application of soap solution showed other smaller leakage paths . The outside damper of each test volume will be visually inspected as soon as possible. Preliminary indications are that the majority of air loss from each test volume is into.

the containment vessel and therefore this leakage does not provide a direct and sizable air flow path between the containment volume and outside

, atmosphere.

The plant has been shut down since January 1,1974 ~for repairs to the turbine resulting from a broken turbine blade. Adjuntments or repairs will be completed to ensure that the dampers are within the Technical Specification limits prior to refueling, b

kDOC 05 $4 \ $. Verypqly yours, g S PDR ( '

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?WY J C. E. Pliitt, Superinterjdcht. .

f.* gd xc: Mr. J. F. O' Leary , .Ginna Sta gg ,yg. ,

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