ML20077E889
| ML20077E889 | |
| Person / Time | |
|---|---|
| Site: | Summer  |
| Issue date: | 06/05/1991 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20077E879 | List: |
| References | |
| NUDOCS 9106110278 | |
| Download: ML20077E889 (2) | |
Text
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UNITED STATES 2
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WASHINof oN, D C 70%6 SAFETY EVALUATION BY THE Off!CE Of NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 99 TO FACILITY OPERATING LICENSE NO. NPT-12 SOUTH CAROLINA ELECTRIC & GAS COMPANY ud1H CAROLINA PUBLIC SERVICE AUTHORITY VIRGIL C. SUMMER NUCLEAR STATION, UNIT N0. 1 DOCKET NO. 50-395
1.0 INTRODUCTION
By letter dated February 4,1991, as supplemented March 27, 1991, South Crirolina Electric & Gas Company submitted a request for a change to the Virgil C. Summer Nuclear Station, Unit No.1 (Summer Station), Technical Specifications (Ts).
The proposed change would separate the loss of offsite power (LOOP) test from i
the 24-hour load test in order to obtain more flexible outage scheduling and to avoid unnecessary cycling of the emergency diesel generator (EDG). The hot restart capability of the EDG would still be demonstrated by bringing the l'DG to a full-load stabilized operating temperature before initiating the LOOP test. The March 27, 1991, supplement renumbered a surveillance requirement (SR) and did not affect the staff's finding of no significant hazards considera-tion.
2.0 EVALUATION Existing Summer Station TS SR 4.8.1.1.2.g.7.d requires that a simulated LOOP test per SR 4.8.1.1.2.g 4.b be performed within 5 minutes following completion of the diesel generator 24-hour load test. The purpose of performing the LOOP test rcquirement within 5 minutes of the 24-hour performance test is to o eure diesel generator hot restart capability at full-load operating temperat,e l
conditions. The present SR 4.8.1.1.2.g 7.d includes in it the performance of the LOOP test after each 24-hour load test.
These tests are required at least once per 18 months.
The licensee has proposed to delete the simulated LOOP test requirement from SR 4.8.1.1.2.g.7.d. and instead has proposed to add the simulated LOOP test requirement in new SR 4.8.1.1.2.g.14 The new SR will include a requirement for stabilization of full-load operating temperature prior to conducting the simulated LOOP test.
This is similar to the existing requirements.
The licensee states that past operating experience has demonstrated that oper-ation of the emergency diesel generators under loads of 4150 to 4250 KW results in the diesel generator reaching full load temperatura in less than 1-hour, and that this temperature remains essentially constant throughout the 24-hour run period.
Based on the above mentioned information (i.e. only a 1-hour warmup period is required at rated load in order to achieve a stabilized operating m oc11oD70 910605 GOR ADfX U 0500(0 5 r.
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-2 temperature), the licensee has stated that it is not necessary to couple the simulated LOOP test to the diesel generator 24-hour load test.
In addition, this existing requirement to schedule the stimulated LOOP test within 5 minutes of completing the 24-hour load test reduces flexibility, leads to unnecessary cycling of the emergency diesel generators and creates the potential for critical path scheduling complications and delays.
The staff agrees with the licensee that there is no technical basis to specify that the stimulated LOOP test start within 5 minutes of the completion of the 24-hour load test as long as this test is conducted when the EDG has achieved a stabilized operating temperature.
Therefore, the licensee's proposed change to conduct the simulated LOOP test independent of the diesel generator 24-hour load test per new SR 4.8.1.1.2.g.14 is found acceptable.
3.0 STATE CONSULTATION
In accordance with the Commission's regulations the South Carolina State l
official was notified of the proposed issuance of the amendment.
The State i
official had no comments.
4.0 ENVIRONMENTAL CONSIDERATION
The amendnient changes a requirement with respect to installation or use of a i
facility component located within the restricted area as defined in 10 CFR i
Part 20 and changes surveillance requirements.
The NRC 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 occupa-tional radiation exposure.
The Commission has previously issued a proposed finding that the amendment involves no significant hazards consideration, and there has been no public comment on such finding (56 FR 9385).
Accordingly, the amendment meets the eli i
forth in 10 CFR 51.22(c)(9)gibility criteria for categorical exclusion set Pursuant to 10 CFR 51.22(b) no environmental impact statement or environment:al assessment need be prepareo in onnection with the issudnce of the: daendfient.
i 5.0 CONCLUS10,J The Commission has concluded, based on the consir.erations discussed above, tnot:
(1) there is reasonable assurance that the health and safety of the l
public will not be endangered by operation in the proDosed nann s'
activities will be conducted in compliance with the canniss % 't r. r" r i i
and (3) the issuance of the amendment will not be inin;ical to the common i
defense and security or to the health and safety of the public.
Principal Contributor:
R. Jenkins i
nate: June 5, 1991 l
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