ML20082V144
| ML20082V144 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 09/06/1991 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20082V136 | List: |
| References | |
| GL-90-09, GL-90-9, NUDOCS 9109230128 | |
| Download: ML20082V144 (3) | |
Text
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SAFETY EVALUATION SY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 66 TO FACILITY OPERATING LICENSE N0. DPR-80 AND AMENDMENT NO. 65 TO FACILITY OPERATING LICENSE N0. DPR-82 PACIFIC GAS AND ELECTRIC COMPANY DIABLO CANYON NUCLEAR POWER PLANT, UNIT NOS. 1 AND 2 DOCKET NOS. 50-275 AND 50-323
1.0 INTRODUCTION
By letter dated March 18, 1991, as supplemented by letter dated May 3,1991, Pacific Gas and Electric Company (PG&E or the licensee) requested amendments to Facility Operating License DPR-80 and DPR-82 for Diablo Canyon Units 1 and 2, respectively.
The amendment application is designated License Amendment Request LAR 91-02.
The amendments change the combined Diablo Canyon technical specifications (TS) by revising TS 3/4.7.7.1, " Snubbers," and the associated Bases to make the snubber visual inspection intervals and corrective actions conform to the recommendations of Generic Letter (Gi ) 90-09, " Alternative Requirements for Snubber Visual Inspection Intervals and Corrective Actions,"
issued on December 11, 1990.
2.0 E VAL L'ATION The snubber visual examination schedule in the previous TS was based on the permissible number of inoperable snubbers found during the visual examination.
Because the previous snubber visual examination schedule was based only on the absolute number of inoperable snubbers found during the visual examinations irrespective of the total population of snubbers, licensees with a large snubber population find the visual examination schedule excessively restrictive. The purpose of the alternative visual examination schedule is to allow the licensee to perform visual examinations and corrective actions during plant outages without reduction of the confidence level provided by the l
previous visual examination schedule. The revised visual examination schedule specifies the permissible number of inoperable snubbers for various snubber populations. The basic examination interval is the normal fuel cycle, up to 24 months. This interval may be extended to as long as twice the fuel cycle or reduced to as small as two-thirds of the fuel cycle depending on the number of unacceptable snubbers found during the visual examination. The i
examination interval may vary by plus or minus 25 percent to coincide with the actual outage.
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9109230128 910906 ADOCK OSO g 5 PDR P
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o... In the event one or more snubbers are found inoperable during a visual examination, the Limiting Conditions for Operation (LCOs) in the previous TS required the licensee to restore or replace the inoperable snubber (s) to operable status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or declare the attached system inoperable and follow the appropriate action statement for that system. This LC0 will remain in the amended TS. However, the permissible number of inoperable snubber (s) and the subsequent visual examination interval will now be determined in accordance with the new visual examination schedule given in Table 1 of GL 90-09. As nuted in the guidance in GL 90-09 for this line item TS improvement, certain corrective actions may have to be perforred depending on the number of inoperable snubbers found. All requirements for corrective actions and evaluations associated with the use of visual examination schedule and stated in footnotes 1 through 7 of GL 90-09 have been included in the TS.
In sumary, the licensee has proposed changes to TS 3/4.7.7.1, " Snubbers,"
that are consistent with the guidance provided in GL 90-09 for the replacement of the snubber visual examination schedule with Table 1 (including footnotes 1 through 7) of GL 90-09.
On the basis of its review of this m6tter, the NRC staff finds that the proposed changes to the Diablo Canyon TS are acceptable.
3.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Californie State official was notified of the proposed issuance of these amn.dments.
The State official had no coments.
4.0 ENVIRONMENTAL CONSIDERATION
These amendments involve changes with respect to the installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 and change surveillance requirements.
The staff has determined that the amendments involve 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 radiation exposure. The Comission has previously issued a proposed finding that the amendments involve no significant hazards consideration and there has been no public coment on such finding (56 FR 22471). Accor dingly, these amendments meet t 5e eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). The basis for this determination is that the new snubber visual examination schedule will pennit the licensee to perform visual examinations and corrective action during outages, resulting in a decreose in individual or cun;ulative occupational radiation exposure.
Pursuant to 10 CFR 51.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the issuance of these amendments.
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5.0 CONCLUSION
The Commission has proposed to determine that these amendments involve no significant hazards consideration. The proposed determination was published in the federal Register on May 15, 1991 at 56 FR 22471.
No public comments or requests for hearing were received.
The NRC staff has 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, and (t) such activities will be conducted in compliance with the Commission's regulations, and the issuance of these amendments will not be inimical to the common defense and security or to the health and safety of the public.
Principa1 Contributors:
J. Rajan H. Rood Dated:
September 6, 1991 i
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