ML13316B355
| ML13316B355 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 05/08/1989 |
| From: | Trammell C Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML13316B354 | List: |
| References | |
| NUDOCS 8905120094 | |
| Download: ML13316B355 (3) | |
Text
7590-01 UNITED STATES NUCLEAR REGULATORY COMMISSION SOUTHERN CALIFORNIA EDISON COMPANY SAN DIEGO GAS AND ELECTRIC COMPANY DOCKET NO. 50-206 SAN ONOFRE NUCLEAR GENERATING STATION, UNIT NO. 1 ENVIRONMENTAL ASSESSMENT AND FINDING OFNO SIGNIFICANT IMPACT The U.S. Nuclear Regulatory Commission (the Commission) is considering issuance of an amendment to Provisional Operating License No. DPR-13 issued to Southern California Edison Company, et al., (the licensee), for operation of San Onofre Nuclear Generating Station, Unit No. 1, located in San Diego County, California.
ENVIRONMENTAL ASSESSMENT Identification of Proposed Action: The proposed amendment is a request to provide both neutron and loose-parts monitoring of the reactor vessel internals in light of a recent finding that three of the bolts attaching the bottom of the thermal shield to the reactor vessel are broken. Neutron monitoring would provide information on vibration of the thermal shield. The amendment provides for reporting any exceedance of acceptance criteria and shutdown if the last flexure (upper thermal shield support device) is determined to have broken.
The amendment also provides for a mid-cycle inspection of the thermal shield.
The NRC staff has concluded that the monitoring program and mid-cycle inspection will provide adequate compensation for the degraded fasteners during the next operating cycle. The thermal shield attachment mechanism will be fully repaired at the end of the cycle, which coincides with the required 10-year inservice inspection.
PDR ADOC DCIPDC
2 The Need for the Proposed Action: The proposed amendment is required to provide for monitoring and inspecting the condition of the reactor vessel thermal shield.
Environmental Impacts of the Proposed Action: The proposed action would not involve a significant change in the probability or consequences of any accident previously evaluated. The NRC staff has evaluated the proposed amendment and has determined that operation with degraded fasteners is acceptable. If
-further degradation should occur the thermal shield could shift.position but.
not in such a way as to cause fuel damage. Consequently, any radiological releases resulting from an accident would not be significantly greater than previously determined. The proposed amendment does not otherwise affect routine radiological plant effluents. Therefore, the Commission concludes that there are no significant radiological environmental impacts associated with the proposed amendment. The Commission also concludes that the proposed action will not result in a significant increase in individual or cumulative occupational radiation exposure.
With regard to nonradiological impacts, the proposed amendment does not affect nonradiological plant effluents and has no other environmental impact.
Therefore, the Commission concludes that there are no significant nonradiological environmental impacts associated with the proposed amendment.
The Notice of Consideration of Issuance of Amendment and Opportunity for Hearing in connection with this action was published in the Federal Register on March 2, 1989 (54 FR 8854). No request for hearing or petition for leave to intervene was filed following this notice.
Alternatives to the-Proposed Action:
Because the Commission has concluded that there are no significant environmental impacts associated with the
-3 proposed action, there is no need to examine alternatives to the proposed action.
Alternative Use of-Resources: This action does not involve the use of resources not previously considered in connection with the Final Environmental Statement related to operation of San Onofre Nuclear Generating Station, Unit 1, dated October 1973.
Agencies and Persons Consulted: The NRC staff has reviewed the licensee's request that supports the proposed amendment. The NRC staff did not consult other agencies or persons.
FINDING OF NO SIGNIFICANT IMPACT The Commission has determined not to prepare an environmental impact statement for the proposed amendment.
Based upon the foregoing environmental assessment, the Commission concludes that the proposed action will not have a significant effect on the quality of the humdn environment.
-4 For further details with respect to this action, see the application for amendment dated February 17, 1989, as supplemented March 21 and 23, and May 3, 1989. These are available for public inspection at the Commission's Public Document Room, 2120 L Street, N.W., Washington, D.C., and at the General Library, University of California, P.O. Box 19557, Irvine, California 92713.
Dated at Rockville, Maryland, this 8th day of flay 1989.
FOR THE NUCLEAR REGULATORY COMMISSION Charles M. Trammell, Senior Project Manager Project Directorate V Division of Reactor Projects - III, IV, V and Special Projects Office of Nuclear Reactor Regulation