ML13331B161
| ML13331B161 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 04/05/1989 |
| From: | Trammell C Office of Nuclear Reactor Regulation |
| To: | Baskin K Southern California Edison Co |
| References | |
| TAC-59138 NUDOCS 8904130400 | |
| Download: ML13331B161 (5) | |
Text
April 5, 1989 Docket No.: 50-206 DISTRIBUTION Docket Fi le NRC & LPDRs CTrammell (2)
Mr. Kenneth P. Baskin MVirgilio Vice President JLee Southern California Edison Company OGC-White Flint 2244 Walnut Grove Avenue PD5 Plant File Post Office Box 800 EJordan Rosemead, California 91770 BGrimes ACRS (10)
LTran
Dear Mr. Baskin:
ANolan (EG&G)
SUBJECT:
PLANT-SPECIFIC ATWS MITIGATION SYSTEM ACTUATION CIRCUITRY (TAC NO. 59138)
Re:
San Onofre Nuclear Generating Station, Unit No. 1 In reviewing your letter of October 21, 1988 relating to the above subject, we have determined that the additional information identified in the enclosure is needed to complete our review. In order to maintain our review schedule, your response is requested within 30 days of your receipt of this letter.
The reporting and/or recordkeeping requirements contained in this letter affect fewer than ten respondents; therefore, OMB clearance is not required under Pub. L.96-511.
Please contact us if you should have any questions regarding this request.
Sincerely,
/s/
Charles M. Trammell, Senior Project Manager Project Directorate V Division of Reactor Projects - III, IV, V and Special Projects
Enclosure:
Request for Additional Information cc: w/enclosure:
See next page
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- pJ% REGQ UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 ApriT 5, 1989 Docket No.: 50-206 Mr. Kenneth P. Baskin Vice President Southern California Edison Company 2244 Walnut Grove Avenue Post Office Box 800 Rosemead, California 91770
Dear Mr. Baskin:
SUBJECT:
PLANT-SPECIFIC ATWS MITIGATION SYSTEM ACTUATION CIRCUITRY (TAC NO. 59138)
Re: San Onofre Nuclear Generating Station, Unit No. 1 In reviewing your letter of October 21, 1988 relating to the above subject, we have determined that the additional information identified in the enclosure is needed to complete our review. In order to maintain our review schedule, your response is requested within 30 days of your receipt of this letter.
The reporting and/or recordkeeping requirements contained in this letter affect fewer than ten respondents; therefore, OMB clearance is not required under Pub. L.96-511.
Please contact us if you should have any questions regarding this request.
Sincerely, Charles M. Trammell, Senior Project Manager Project Directorate V Division of Reactor Projects -
- III, IV, V and Special Projects
Enclosure:
Request for Additional Information cc: w/enclosure:
See next page
Mr. Kenneth P. Baskin San Onofre Nuclear Generating Southern California Edison Company Station, Unit No. 1 cc Charles R. Kocher, Assistant Mr. Paul Szalinski, Chief General Counsel Radiological Health Branch James Beoletto, Esquire State Department of Health Southern California Edison Company Services Post Office Box 800 714 P Street, Office Bldg. #,8 Rosemead, California 91770 Sacramento, California 95814 David R. Pigott Orrick, Herrington & Sutcliffe 600 Montgomery Street San Francisco, California 94111 Mr. Robert G. Lacy Manager, Nuclear San Diego Gas & Electric Company P. 0. Box 1831 San Diego, California 92112 Resident Inspector/San Onofre NPS U.S. NRC P. 0. Box 4329 San Clemente, California 92672 Mayor City of San Clemente San Clemente, California 92672 Chairman Board of Supervisors County of San Diego 1600 Pacific Highway Room 335 San Diego, California 92101 Director Energy Facilities Siting Division Energy Resources Conservation &
Development Commission 1516 - 9th Strebt.
Sacramento, California 95814 Regional Administrator, Region V U.S. Nuclear Regulatory Commission 1450 Maria Lane, Suite 210 Walnut Creek, California 94596
ENCLOSURE SAN ONOFRE NUCLEAR GENERATION STATION, UNIT 1 COMPLIANCE WITH ATWS RULE 10CFR 50.62 REQUEST FOR ADDITIONAL INFORMATION The following list of comments/questions were developed from the review of the licensee's submittal of October 21, 1988, which is the response to a request for information dated May 31, 1988. The additional information is needed in order to continue or to close out the review.
- 1. In response to questions on the isolation devices used in the SPDS and ATWS circuits, the submittal states "credit is taken for circuit overcurrent protective devices."
The staff finds this position to be unacceptable. The isolation device when used in safety-related applications is required to function alone in protecting the safety-related circuits from voltage/current faults that originate in the associated non-safety related side of the isolator. However, the staff encourages the use of overcurrent protective devices in these isolator circuits to limit fault currents and to serve as a backup to a fully qualified isolator, as necessary.
Therefore, the staff finds the licensee's response, in this instance, to be incomplete, and requests a response to Question No. 2, Section B of our previous request for additional information with details that address the information requested.
-2
- 2. In response to questions on the qualification of isolation devices used in ATWS modifications, the staff does not consider the CCC Model 8N13 relay to be sufficiently qualified for service in related ATWS circuits. Successful Hypot tests and dielectric strength tests alone are not sufficient to conclude that the Class IE to non-Class,IE isolator will successfully withstand the challenge of the maximum credible fault (MCF) voltage/current that could originate in the non-safety side of the isolation device.
For this reason, the staff requests the licensee to provide additional detail to answer Question No. 3, Section B of our previous request for additional information regarding MCF testing of the CCC Model 8N13 relay.
- 3. The DTT must be diverse from the RTS. The DTT isolators being a part of the DTT must also be diverse from the RTS isolation relays. The staff's SER approving the WCAP only gives credit for the non-diverse input isolators that are associated with the input sensors and their signals.
Credit is not given for the non-diversity of any other isolators associated with ATWS.
The licensee should qualify an isolator for use in the DTT that is diverse from the isolators used in the RPS.
- 4. The electrical and physical separation of power between AFAS-Trn "B"/DTT from the RPS is not clear from the data provided. DWG 5146828-25 does not address the DTT power source nor does it show the tie-in for the 125 VDC Bus 2.,.Breakers 8-11B26 and 8-12B26 are not shown. Please provide the necessary information.