ML13308B513
| ML13308B513 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 03/08/1973 |
| From: | Coe R SOUTHERN CALIFORNIA EDISON CO. |
| To: | US ATOMIC ENERGY COMMISSION (AEC) |
| References | |
| NUDOCS 8103060682 | |
| Download: ML13308B513 (3) | |
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Southern California Edison Company gCE P. 0. BOX 800 2244 WALNUT GROVE AVENUE ROSEMEAD, CALIFORNIA 91770 TELEPHONE ROBERT N. COE VICE
-N March 8,
1973 Deputy Director for Reactor Projects Directorate of Licensing U. S. Atomic Energy Commission 1717 "H" Street N. W.
Washington, D. C.
20545 TN Docket Number 50-206 San Onofre Unit 1 Earthquake of February 21, 1973
Dear Sir:
The following report describes an earthquake event as experienced at San Onofre Unit 1:
At 6:47 a.m. on February 21, 1973, a moderate earthquake was felt at San Onofre. No unusual condition resulted from the earthquake with the following exceptions:
- 1. The initiation of accelerograph instrumentationwhich monitors various plant equipment.
- 2. Vibration on the turbine Number 1 bearing increased from approximately.5 mil to 5.9 mils and returned to normal.
Procedures as outlined in applicable station instructions were conducted as follows:
- 1. A comprehensive physical inspection was made of all plant equipment, systems and buildings external to the containment and no unusual conditions found.
- 2. All control rods were exercised and operated normally.
- 3. No. 2 Diesel-Generator was tested and operated satisfactorily.
No. 1 Diesel-Generator was out of service for maintenance at the time.
- 4. The Reactor Coolant System leak rate test was performed and found normal.
ffDOCKETED UMAEC (o
MAR 141973 1728 REGULATORY IMAIL SECTION c,&T.
UO~fCERK
Docket Number 50-206 March 8, 1973
- 5. The sphere sump and reactor cavity pumps did not operate, indicating no increase in leakage rates to the containment.
- 6. The new fuel storage room and spent fuel pit were inspected and found normal.
- 7. No change was noted in reactor core reactivity.
- 8. Containment sphere particulate and gaseous radioactivity indications remained normal.
For your information, acceleration levels as recorded on the plant seismic sensors are included on Attachment 1.
Sincerely, ROBERT N. COE WDM/WGZ/mlh Attachment cc:
Director, Region V Regulatory Operations Office
SAN ONOFRE NUCLEAR GENERATING STATION ATTACHMENT 1 February 21, 1973 - Earthquake Location Measured in Units Sensor No.
Within Containment Orientation of Accelerat-ion (g's) 103-1 Refueling Deck Longitudinal
.003 Transversal
.004 Vertical
<.001 103-2 Grade-10 Elevation Longitudinal
.002 Transversal
.003 Vertical
.001 103-3 Top of Pressurizer Longitudinal
.015 Transversal
.010 Vertical 103-4 Reactor Coolant Longitudinal Pump 'B' Transversal Vertical 103L5
'B' Steam Generator Longitdiiall Transversal Vertical 103-6 Top of Containment Longitudinal
.006 Transversal
.005 Vertical
<.002 NOTES:
- Masked by background.
Recorder inoperative.
Repairs effected.