ML20236U778

From kanterella
Revision as of 19:48, 19 February 2021 by StriderTol (talk | contribs) (StriderTol Bot insert)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to navigation Jump to search
PN-75-064:an Earthquake Registering 5.7 on Richter Scale at Univ of California,Berkeley & 6.4 at California Institute of Technology,Pasadena,Occurred in Vicinity of Oroville,Ca on 750801
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)


Text

--

c pff yw q p 7 py);tjza l

PRELIMINARY NOTIFICATION - NOT FOR PUBLIC DISCLOSURE August 4, 1975 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE --PN-75-64 a

{5ee,aeaV This preliminary notification constitutes EARLY notice of events of 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 l

NOTIFICATION MAY CONTAIN INFORMATION THAT LATER MAY BE DETERMINED TO BE INACCURATE OR INCONSISTENT. AN OFFICE OF INSPECTION AND ENFORCEMENT I 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:

Earthquake ~

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

.a remained normal. Detailed analysis of the recorded seismic data

( 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 occurrence by telephone from Ron Col ~ombo of SMUD at 4:40 p.m.(EDT) g on August 1, 1975. --

(

o Contact.FGHSmith,15'x7261 HDThornburg, IE x7353 JGDavis, IE x7541 ~ .d 8 m x4 Distribution: J- '1 f ' '

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 PRELIMINARY NOTIFICATION - NOT FOR PUBLIC DISCLOSURE j