ML20031H441
| ML20031H441 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 10/14/1981 |
| From: | Curran J SOUTHERN CALIFORNIA EDISON CO. |
| To: | Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| References | |
| 10CFR-050.55E, 10CFR-50.55E, IEB-80-06, IEB-80-6, NUDOCS 8110270483 | |
| Download: ML20031H441 (2) | |
Text
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Docket Nos. 50-361/362-v F
50 5$(e) Report 8
f.
Southern California Edison Company b
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Lo-P. O. BOX 800 2244 WALNUT GROVE AVENUE ROSEMEAD CALIFORNI A 917 70 J. M. CU R R AN og,wong October 14, 1981 i"""'
..~......u.u n.uu...c.
e ib,N Mr. R. H. Engelken, Director
/S Office of Inspection and Enforcement
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O U. S. Nuclear Regulatory Commission U{
Region V
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OCTg O 798A ~
Suite 202, Walnut Creek Plaza
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1990 North California Boulevard Walnut Creek, California 94506 b-
Dear Mr. Engelken:
I' Subj ect:
Engineered Safety Features Actuation System (ESFAS)
San Onofre Nuclear Generating Station, Units 2 and 3
Reference:
IE Bulletin No. 80-06 By letter dated September 15, 1981.we notified you of a condition discovered in system testing which we con-sidered to be potentially reportable in accordance with 10CFR50.55(e).
The system testing was conducted as a response to the referenced IE Bulletin.
The-condition discovered con-cerned certain stfety-related equipment which did not remain in the emergency mode when the ESFAS signal was reset./
In subsequent evaluations and review of all the ESF system elementary diagrams, we concluded that the concerns expressed in the referenced bulletin were not valid for the San Onofre Units 2 and 3 design.
At no time is the protective system action compromised upon reset of an emergency actua-tion signal.
With the exception of the volume control tank (VCT) outlet valve, all changes in compment operating modes are consistent with the desired operatirg mode of the system following safety signal reset.
Upon race ting the safety signal (SIAS), the volume control tank outlet valve will reopen if tank level is normal and the valve control system is in the automatic mode.
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._4 Mr. R. H. Engelken 2-October 14, 1981 We will revise the emergency procedures to require the VCT outlet valve to be placed in the manual mode prior to safety signal reset as an interim corrective measure.
The~
design of the VCT outlet valve circuitry will be revised during the first refueling to preclude the valve from changing position upon safety signal reset.
It is concluded that no significant deficiency exists in Engineered Safety Features Actuation System and is therefore not re. portable in accordance with 10CFR50.55(e).
If you have any questions regarding this matter we would be pleased to discuss them with you at your convenience.
Sincerely,
. h.
cc:
Dr. L. T. Papay A. E. Chaffee (NRC, San Onofre Units 2 and 3) i i
m m
.