ML19256D010
| ML19256D010 | |
| Person / Time | |
|---|---|
| Site: | Rancho Seco |
| Issue date: | 07/02/1979 |
| From: | Klingler G NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| To: | |
| References | |
| PNO-79-206, NUDOCS 7910150853 | |
| Download: ML19256D010 (1) | |
Text
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PRELIMINARY N0_TIFICATION July 2,1979 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE- 'N0-79-206 This preliminary notification constitutes EARLY notice of an event of POSSIBLE safety or public interest significa7ce.
Tne information presented is as initially received without verification or evaluation and is basically all that is known by IE staf ' on this date.
FACILITY:
Sacramento Municipal Utility District Rancho Seco Nuclear Power Plant Docket No. 50-312 Sacramento, California
Subject:
AUTOMATIC PLANT SHUTDOWN FROM LOW POWER FOLLOWING TEST OF MANUAL CONTROL OF AUXILIARY FEEDWATER The Rancho Seco plant sustained an automatic shutdown from 15% power on July 1, 1979 at approximately 2:00 p.m.
The shutdown was initiated by high reactor coolant pressure when a 6-inch startup feedwater valve closed momentarily following successful demonstration of operator capability to assume manual control of the auxiliary feedwater system (AFS).
The feedwater system had been returned to integrated control system control just prior to the occurrence.
Subsequent to the unit trip, a 3/4-inch vent line in the auxiliary steam system was discovered to be broken.
The plant has been brought to a cold shutdown condition to repair the broken vent line.
Plant startup may be delayed by possible need to repair a broken baffle plate in the plant's oil-fired auxiliary boiler which is needed for plant heatup.
The licensee has notified the news media of this occurrence, and there has been local and San Francisco Bay Area coverage by radio, TV and newspapers.
Region V (San Francisco) inspectors were onsite at the time of the occurrance.
The Region V office was informed by an inspector onsite at 8:00 a.m. on July 2, 1979.
Contact:
G. Klingler IE, x28019 F. Nolan IE, x28019 S. Bryan IE, x28019 Distribution:
Transmitted H St Cnairman Hendrie Commissioner Bradford S. J. Chilk, SECY Cc=issioner Kennedy Commissioner Ahearne C. C. Kammerer, CA Commissioner Gilinsky ACRS (For Distribution)
Transmitted:
MNBB P. Bldg S'4d V. Stello, IE
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L. V. Gocsick, EDO H. R. Denton, NRR Region y H. L. Ornstein, EDO R. C. DeYoung, NRR J. J. Fouchard, PA R. J. Mattson, NRR N. M. Haller, MPA D. Vassallo, NRR (MAIL)
R. G. Ryan, OSP D. Eisenhut, NRR J. J. Cummings, 0IA H. K. Shapar, ELD SS Bldg R. Minogue, SD W. J. Dircks, NMSS gM b j
S. Levine, RES PRELIMINARY NOTIFICATION 7 91015 0 MF3 J
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