ML20041E949
| ML20041E949 | |
| Person / Time | |
|---|---|
| Site: | Brunswick  |
| Issue date: | 03/05/1982 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20041E948 | List: |
| References | |
| NUDOCS 8203160004 | |
| Download: ML20041E949 (2) | |
Text
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p>* "'W;jg, UNITED STATES p,
NUCLEAR REGULATORY COMMISSION g
.p W ASHINGTON, D. C. 20555 4, +... * #
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NO. 46 TO FACILITY LICENSE N0. DPR-71 AND AMENDMENT N0. 69 TO FACILITY LICENSE NO. DPR-62 CAROLINA POWER & LIGHT COMPANY BRUNSWICK STEAM ELECTRIC PLANT, UNITS 1 AND 2 DOCKET N05. 50-325 AND 50-324 Author: J. Van Vliet I.
INTRODUCTION By letter dated February 3, 1982, Carolina Power & Light Company (Licensee) requested an amendment to the Brunswick Units 1 and 2 Operating Licenses.
The proposed amendments would extend certain surveillance intervals to allow required testing to be performed during the upcoming Brunswick Unit 2 refueling outage. The tests involve 18-month surveillance normally performed during refueling outages. The licensee provided supplemental information under a February 25, 1982 submittal.
II.
BACKGROUND AND DISCUSSION TFa licensee's request for an extension of certain surveillance intervals was submitted as a result of extended in-cycle maintenance outages on the Brunswick units. These outages have acted to delay the refuelings such that the Brunswick Unit 2 refueling outage is currently not scheduled to begin prior tc _xpiration of certain surveillance intervals. The licensee has determined that system load requirements will necessitate maintaining Brunswick Unit 2 in service until its refueling outage scheduled to begin prior to May 1,1982. The licensee has thus determined that the optimum alternative is to complete all of these surveillance requirements during the upcoming refueling outage.
The licensee's submittal included information demonstrating that the systems involved have a record of satisfactory performance on the first attempt during the most recent tests, as well as a satisfactory record of earlier tests.
The licensee has also performed a safety analysis and concluded that extending these surveillance intervals will not impact:
(1) The probability of occurrence or consequences of an accident or malfunction of equipment important to safety previously evaluated in the Final Safety Analysis Report (FSAR); (2) the 8203160004 820305 PDR ADOCK 05000324 P
2 possibility of creation of an accident or malfunction of a different type than any previously evaltated in the FSAR; and (3) the margin of safety as defined in the bases for Technical Specifications.
III.
EVALUATION i
The NRC staff's requirement for 18-month surveillance intervals was established to coincide and be consistent with nominal cycle lengths.
Technical Specification Section 4.0.2, in recognition of the need for operational flexibility because of scheduling and performance considera-tions, establishes maximum time intervals within which surveillance requirements shall be parformed.
Section 4.0.2 stipulates that:
(1) the maximum allowable extension shall not exceed 25% of the surveillance interval and (2) the total maximum combined time interval for any three consecutive surveillance intervals shall not exceed 3.25 times the specified surveillance intervals. The licensee is proposing to temporarily expand the maximum allowable extension of Section 4.0.2 for certain surveillance requirements without altering the requirement addressing the three consecutive surveillance time intervals.
To judge the acceptability of extending the required surveillance intervals, we have categorized the specific system surveillances into two cases.
Case 1 addresses those surveillance requirements for which the time interval is to be extended by seven days or less.
Case 2 addresses those surveillance requirements for which the time interval is to be extended by eight days or more.
Case 1 addresses surveillance interval extensions of seven days or less for diesel generator load tests and certain isolation actuation instrumentation channel calibrations. The extensions requested by the licensee, when considered with respect to the presently required surveillance interval of 550 days, becomes essentially insignificant.
For this reason we conclude that the extensions will not dearade the reliability.of'the systems in question and are, therefore, acceptable.
Case 2 addresses surveillance interval extensions of tight days or more for tests of the re=ctor protection system (RPS) position switch, automatic depressurization system (ADS) logic, turbine control valve (TCV) fast (iosure, reactor vessel low water levcl #1, and RPS logic.
The requested extensions range from 23 days for the ADS logic tests to 56 days for the RPS logic tests. To evaluate these extensions, we considered the history of previous tests results, the length of the proposed extensions, and whether or not the extensions, if granted, could result in exceeding the
.Section 4.0.2 requirement that three consecutive tests be performed within 3.25 times the surveillance interval.
For the TCV fast closure and reactor vessel low water level #1 tests, we also assessed whether or not the proposed extensions would exceed the requirement to test each logic train every 36 months, and each channel every 72 months.
3 l
The length of the proposed extensions ranges from 4% to 10% beyond the 25% surveillance interval extension permitted by Section 4.0.2.
Considering that the surveillance intervals were initially established generically such that they coincide with nominal refueling cycles, we do not consider the requested extensions of up to 10% to be unreasonable.
Providing further support for this position is the fact that none of the extensions, if granted, would result in exceeding the three consecutive test time interval requirement.
Additionally, the TCV fast closure and reactor vessel low water level #1 tests have other surveillance interval requirements which require testing each logic function every 36 months and each channel every 72 months.
Our review has shown that implementing the proposed extensions will not result in exceeding either the channel or logic surveillance interval requirements for these tests.
The licensee has provided information showing that, for each test in question, the previous test was satisfactory on the first attempt ar.d that each test also has a history of satisfactory results.
Thus it wems reasonable to conclude that the probability of an undetected failure occurring during the test extension periods is very low.
Therefore, for the reasons cited above, we find the proposed extensions acceptable.
The licensee has proposed to implement the extensions, in part, by a license condition for Brunswick Unit 2 that prohibits operating in modes 1, 2, or 3 after May 1, 1982. This will require the plant to be in either mode 4 or mode 5 (cold shutdown or refueling) until the tests are complete.
Because operating modes 4 and 5 do not require these tests to assure plant safety, we find this implementation approach to be -acceptable.
IV.
ENVIRONMENTAL CONSIDERATION We have determined that the amendments do not authorize a change in effluent types or total amounts nor an increase in power level and will not result in any significant environmental impact.
Having made this determination, we have further concluded that the amendments involve an. action which is insignificant from the standpoint of enviornmental impact and pursuant to 10 CFR 151.5(d)(4) that an environmental impact statement, negative declaration, or environmental impact appraisal need not be prepared in connection with the issuance of the amendments.
V.
CONCLUSION We have concluded, based on the considerations discussed above, that:
(1) because the amendments do not involve a significant increase in the probability or consequences of accidents previously considered and do not involve a significant decrease in a safety margin, the amendments do not involve a significant hazards consideration, (2) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, and (3) such a.ctivities will be conducted in compliance with the Commission's regulations and the issuance of the amendments will not be inimical to the common defense and security or to the health and safety of the public.
Dated: March 5,1982