ML20236U778
| ML20236U778 | |
| Person / Time | |
|---|---|
| Site: | Humboldt Bay, Rancho Seco |
| Issue date: | 08/04/1975 |
| From: | Jennifer Davis, Galen Smith, Thornburg H NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| To: | |
| References | |
| PN-75-064, PN-75-64, NUDOCS 9807310040 | |
| Download: ML20236U778 (1) | |
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PRELIMINARY NOTIFICATION - NOT FOR PUBLIC DISCLOSURE August 4, 1975 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE --PN-75-64
{5ee,aeaV This preliminary notification constitutes EARLY notice of events of a
l FOSSIBLE safety or public interest significance.
The information presented is as initially received without verification or evaluation and is basically all that is known by OIE staff as of 11:30 a.m. on the date of this notification.
IT SHOULD BE SPECIFICALLY NOTED THAT THIS NOTIFICATION MAY CONTAIN INFORMATION THAT LATER MAY BE DETERMINED TO l
BE INACCURATE OR INCONSISTENT.
I AN OFFICE OF INSPECTION AND ENFORCEMENT l
NOTIFICATION OF AN INCIDENT OR OCCURRENCE (BLUE SHEET) SUBSEQUENTLY WILL BE ISSUED IF WARRANTED.
.. Facility: Rancho Seco Sacramento Municipal Utility District Humbolt Bay j
Pacific Gas and Electric Company
Subject:
~
An earthquake registering 5.7 on the Richter scale at the University of California, Berkeley, and 6.4 at the California Institute of Tech-nology, Pasadena, occurred in the vicinity of Oroville, California, at 4 :20 p.m. (EDT), August 1,1975.
Oroville is approximately 70 miles north of the Rancho Seco facility. The control room seismic, readout at Rancho Seco indicated a ground acceleration of between.050g and g
.065g Visual examination of the facility (presently shutdown for turbine repair) revealed no damage.. All control room functions remained normal. Detailed analysis of the recorded seismic data
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vill be performed by the licensee.
l Humbolt Bay Nuclear Power Plant located approximately 160 miles northwest of Oroville reported no indication of ground motion.
The Regional Offi'ce reported that actually a series of 10 earthquakes registering greater than 4 on the Richter scale occurred on August I and 2, 1975.
)
Although neither the Region nor the licensees made press releases, there was extensive coverage in the press and on TV of the quake l
and the minor damage that occurred at Oroville.
/
Region V (Walnut Creek, California) received notification of this g
occurrence by telephone from Ron Col ~ombo of SMUD at 4:40 p.m.(EDT)
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on August 1, 1975.
o Contact.FGHSmith,15'x7261 HDThornburg, IE x7353 JGDavis, IE x7541 ~
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Distribution:
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'1 Chairman Anders Commissioner Mason S. J. Chilk, SECY
$e Commissioner Gilinsky Commissioner Rowden G. F. Murphy, JCAE
@ M Commissioner Kennedy C. C. Kammerer, CA mg d $
L. V. Gossick, EDO D. F. Knuth, IE J. A. Harris, PA
, (,d@ M B. C. Rusche, NRR H. H. Brown, ISP T. J. McTiernan, AIA PLE K. R. Chapman, NMSS H. K. Shapar, ELD Transmitted: P Bldg J2l#E ; H Ste2l66 ; MNBB 3 h ;
Lugeg I
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PRELIMINARY NOTIFICATION - NOT FOR PUBLIC DISCLOSURE j