ML13316B065
| ML13316B065 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 08/17/1988 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML13316B063 | List: |
| References | |
| GL-84-15, TAC-60369, NUDOCS 8808260195 | |
| Download: ML13316B065 (4) | |
Text
P7o UNITED STATES 0
NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT N0.106TO PROVISIONAL OPERATING LICENSE NO. DPR-13 SOUTHERN CALIFORNIA EDISON COMPANY SAN DIEGO GAS AND ELECTRIC COMPANY SAN ONOFRE NUCLEAR GENERATING STATION, UNIT NO. 1 DOCKET NO. 50-206 Introduction By letter dated December 19, 1985 Southern California Edison Company requested changes to the San Onofre Nuclear Generating Station Unit 1 Technical Specifications (Proposed Change No. 148) with the stated purpose of incorporating into the Technical Specifications the recommendations of Generic Letter 84-15 regarding actions to improve and maintain emergency diesel generator reliability. Also, a change to the Basis section of the Technical Specifications was requested regarding the addition of a fourth San Diego Gas & Electric Company high voltage line as an offsite power source. Additional information was supplied with regard to this change by Southern California Edison Company letter dated April 28, 1987. Following is the staff's evaluation of the requested changes:
Evaluation
- 1. Action Statement 3.7.I.B.1 This action statement specifies the required actions for inoper ability of one of the required offsite circuits. The statement originally required that the diesel generators be tested within one hour and at least once per eight hours thereafter following the loss of the offsite circuit. This has been changed so that the diesel generators only have to be tested once within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> following the loss of the offsite circuit. We find this change consistent with the intent of Generic Letter 84-15 to improve and maintain diesel generator reliability by reducing excessive diesel generator testing.
Because this change should result in increased availability of the diesel generators and therefore increased safety of the plant we find it acceptable.
- 2. Action Statement 3.7.I.B.2 This action statement specifies the required actions for inoperability of one diesel generator. As in the above action statement 3.7.I.B.1 the requirement to test the remaining operable diesel generator within
- 38808260195 880)817 PDR ADOCK 05000206 P
-2 one hour and at least once per eight hours thereafter has been deleted, and a requirement to test the diesel generator once within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> has been substituted. This change is acceptable as previously stated in the above action statement 3.7.I.B.1.
Additionally, the licensee has proposed a seven day out-of-service (LCO) action statement for diesel generator inoperability in lieu of the current technical specification requirement of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. Together with the longer out-of-service interval, the licensee has proposed in a new footnote to this action statement that the aggregate of the combined out of service times for the two diesel generators (exclusive of plant operation in Modes 5 and 6) during any consecutive 365-day period shall not exceed 800 hours0.00926 days <br />0.222 hours <br />0.00132 weeks <br />3.044e-4 months <br /> without notification to the NRC.
The staff presently does not have a regulatory basis for accepting changes related to allowable cumulative inoperability limits and increased LCOs for diesel generators. The basis for acceptance of these changes would have to be developed and processed through the staff's generic review process with ultimate approval by the Committee to Review Generic Requirements (CRGR).
For this reason we do not approve these two changes to the technical specifications at this time. Our Office of Nuclear Regulatory Research has been forwarded a copy of the request for consideration.
- 3. Action Statement 3.7.I.B.3 This action statement specifies the required actions for inoperability of one offsite circuit and one diesel generator. The requirement to test the remaining operable diesel generator within one hour and at least once per eight hours thereafter has been deleted, and a require ment to test the diesel generator once within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> has been substi tuted. This test once within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> as compared to the previous two action statements which required a test of the operable diesel generators once within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is reasonable in light of the increased number of power sources out of service (two versus one) and the resulting need to more quickly determine the availability of the remaining power sources. We find this change consistent with the intent of Generic Letter 84-15 to improve and maintain diesel generator reliability by reducing excessive diesel generator testing. Because this change should result in increased availability of the diesel generators and therefore increased safety of the plant, we find it acceptable.
As in the previous action statement 3.7.I.B.2, the licensee has proposed a seven day LCO for diesel generator inoperability and an 800 hour0.00926 days <br />0.222 hours <br />0.00132 weeks <br />3.044e-4 months <br /> total out-of-service time in any 365-day period for both diesel generators.
As explained above, the staff presently does not have a regulatory basis for accepting changes related to allowable cumulative inoperability limits and increased LCOs for diesel generators. The basis for acceptance of these changes would have to be developed and processed through the staff's generic review process with ultimate approval by the CRGR.
-3 For this reason we do not approve these two changes to the technical specifications at this time. As in Item 2 above, our Office of Nuclear Regulatory Research has been forwarded a copy of the request for consideration.
- 4. Action Statement 3.7.I.B.4 This action statement specifies the required actions for inoperability of two offsite circuits. As in the previous action statement, 3.7.I.B.3, the requirement to test the operable diesel generators within one hour and at least once per eight hours thereafter has been deleted, and a requirement to test the diesel generators once within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> has been substituted. We find this change consistent with the intent of Generic Letter 84-15 to improve and maintain diesel generator reliability by reducing excessive diesel generator testing. Because this change should result in increased availability of the diesel generators and therefore increased safety of the plant, we find it acceptable.
- 5. Action Statement 3.7.I.B.5 This action statement specifies the required actions for inoperability of two diesel generators. The proposed action statement contains the longer LCO of seven days to restore both diesel generators to operable status in lieu of the current required LCO of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. It also references the footnote limiting to 800 hours0.00926 days <br />0.222 hours <br />0.00132 weeks <br />3.044e-4 months <br /> the total out-of-service time in any 365-day period for both diesel generators. The staff presently does not have a regulatory basis for accepting changes related to allowable cumulative inoperability limits and increased LCOs for diesel generators. The basis for acceptance of these changes would have to be developed and processed through the staff's generic review process with ultimate approval by the CRGR. For this reason we do not approve these two changes to the technical specifications at this time. As in Items 2 and 3 above, our Office of Nuclear Regulatory Research has been forwarded a copy of the request for consideration.
- 6. Basis to Technical Specification 3.7 The first two paragraphs of the Basis to Technical Specification 3.7 have been revised to reflect the fact that four (instead of three)
San Diego Gas and Electric Company (SDG&E) high voltage lines presently serve San Onofre. By letter dated April 28, 1987 the licensee provided information that the load capacity of the fourth line is the same as for the original three, and the physical independence of the two required offsite power systems at San Onofre is not affected by the additional fourth line. Because the existing San Onofre Unit 1 Technical Specification allows any one of the three original SDG&E high voltage lines to serve as one of the offsite power sources to San Onofre Unit 1, and because the additional fourth SDG&E line is
-4 equivalent to any of these other three lines in terms of capacity and independence, we find that this new line is also acceptable as an offsite power source to San Onofre Unit 1. This change is therefore acceptable.
- 7. Environmental Consideration This amendment involves changes in surveillance requirements. The staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite and that there is no significant increase in individual or cumulative occupational radi ation exposure. The Commission has previously issued a proposed finding that this amendment involves no significant hazards consider ation and there has been no public comment on such finding. According ly, this amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the issuance of this amendment.
- 8. Conclusion We have concluded, based on the considerations discussed above, that:
(1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations and (3) the issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor: J. Lazevnick Dated: August 17, 1988