ML20249B510

PNO-76-105:on 760617,7,000 Gallons of Water Leaked to Containment from 3/8 Inch Flexible Pressure Hose in RCS Pressure Transmitter Line.Appears That Operators Failed to Respond to Sump Pump Alarms & Addl Pump Operation

ML20249B510
Person / Time
Site:	Beaver Valley
Issue date:	06/18/1976
From:	Dreher F, Roy G, Thompson D NRC OFFICE OF INSPECTION & ENFORCEMENT (IE)
To:
References
PNO-76-105, NUDOCS 9806230243
Download: ML20249B510 (1)

Text

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• PRELIMINARY NOTIFEC1 TION Juns 18, 1976 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE--PNO-76-105

_This preliminary notification constitutes EARLY notice of an event of POSSIBLE safety or public interest significance. The information presented is as initially received without verification or evaluation and is basically all that is known by IE staff on this date.

Facility: Beaver Valley 1 (DN 50-334)

Duquesne Light Company

Subject:

REACTOR COOLANT SYSTEM (RCS) LEAK TO COITIAINMENT During the period from 9:00 a.m. to 12:00 midnight on June 17, 1976, 7000 gallons of water leaked to Containment from a 3/8 inch flexible pressure hose in 3 Reactor Coolant System pressure transmitter line.

. The flexible hose was inserted in place of a portion of 1/2 inch solid line after hot functional testing to reduce vibration at the trans-mitter. The operators failed to recognize the leak until 7:22 p.m. due, in part, to varying loads and temperature changes that affected the system water inventory and to the low radioactivity level of the reactor coolant. The reactor was operating in a test phase at power levels up a to 28 percent. It appears the operators failed to respond to sump pump alarms and to additional pump operation.

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Containment inspection, cleanup, and resolution of any instrument or mechanical problems caused by the water are in progress. The flexible hose is being replaced with solid tubing of original design.

Media interest is expected. The Commonwealth of Pennsylvania has been informed. A press release is not planned.

Region I, NRC, Philadelphia, PA received notification of this occurrence 9j by telephone from the Chief Engineer at 11:50 a.m., June 18, 1976. NRC:I Inspectors are enroute to the site to review the event itself and evaluate

, the performance of the relatively new crew. 4 F

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Contact:

FADreher, IE x27261 GWRoy, IE x27261 DThompson, IE x27541 t

Distribution:

Chairman Rowden Commissioner Mason S. J. Chilk, SECY l i Commissioner Gilinsky C. C. Kammerer, CA G. F. Murphy, JCAE l Commissioner Kennedy L. V. Gossick, EDO E. Volgenau, OIE J. A. Harris, PA

B. C. Rusche, NRR J. La Fleur, ISP T. J. McTiernan, AIA K. R. Chapman, NMSS H. K. Shapar, ELD Transmitted

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