ML20151U484

PNO-77-057:on 770415,inside Containment Instrument Air Supply Was Lost,With Reactor Operating at 100% Power.Reactor Expected to Be Shutdown Approx 10 Days to Insp & Replace RCP Seals

ML20151U484
Person / Time
Site:	Saint Lucie
Issue date:	04/18/1977
From:	Dreher F, Roy G, Thompson D NRC OFFICE OF INSPECTION & ENFORCEMENT (IE)
To:
References
PNO-77-057, PNO-77-57, NUDOCS 9809110019
Download: ML20151U484 (1)

Text

Oc y .

~ l wu3 PRELIMINARY NOTIFICATION .

April 18, 1977 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE--PN0-77-57 s

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: St. Lucie Unit No.1 Florida Power and Light Company

Subject:

REACTOR SHUTDOWN DUE TO LOSS OF INSTRUMENT AIR WITH SUBSEQUENi DAMAGE TO REACTOR COOLANT PUMP (RCP) SEALS At 3:39 p.m. on April 15, 1977, with the reactor operating at 100 percent power, inside containment instrument air supply was lost. As a result, Reactor Coolant Pump (RCP) seal water injection flow and component cooling water to the RCP thermal barrier were lost due to the air-operated valves i closing. In addition, the pressurizer spray valve, Reactor Coolant System

(RCS)letdownvalveandquenchtankdrainvalveclosed. The reactor was

>! manually tripped. Outside instrument air supply was valved into contain-

ment. However, RCP seal damage was indicated by high differential pressures

, on the seals and the decision was made not to restart any of the four RCP's.

Cooldown was by the natural circulation method to 290 degrees Fahrenheit,

• which was achieved at 1:50 a.m. on April 16. At 290 degrees Fahrenheit, the .

' shutdown cooling system was placed in service. FP&L reported that there was no degradation of the reactor coolant system (RCS) boundary, 'no loss of coolant into containment, or radioactive release to the environment.

The Reactor is expected to be shutdown approximately 10 days to inspect and replace RCP seals.

Region II contacted the local newsmedia near St. Lucie and FP&L has responded to local media inquiries. _ _ , .

J Region II received notification of this occurrence via telephone at . l 1130 hours0.0131 days <br />0.314 hours <br />0.00187 weeks <br />4.29965e-4 months <br /> on Saturday, April 16, 1977, o j i

Contact:

FADreher, IE x27261 GWRoy, IE x27261 DThompson, IE x27541 _. i g ou ,

Distribution: Transmitted H St //NY# ' l Chairman Rowden C. C. Kammerer, CA G. F. Murphy, JCAE '

Commissioner Gilinsky S. J. Chilk, SECY H. H. Whiteside, SCHR H. R. Myers, hCEE Transmitted: MNBB N Fd A . P Bl dg M Q /A* - SS Bldg /// N# -

i L. V. Gossick, ED0 B. C. Rusche, NRR K. R. Chapman, NMSS

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l l S. H. Hanauer, ED0 H. K. Shapar ELD i J. A. Harris, PA ,

j W. G. Mcdonald, MIPC Luge (MAIL) E. Volgenau. IE I R. G. Ryan, OSP T. J. McTiernan, 0IA Region g // : f 6 j

t 9809110019 770418 i PDR I8:E .

i PNG-77-057 PDR j 2 . . ~ o