ML20235G260
| ML20235G260 | |
| Person / Time | |
|---|---|
| Site: | Brunswick  |
| Issue date: | 09/24/1987 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20235G230 | List: |
| References | |
| NUDOCS 8709290518 | |
| Download: ML20235G260 (2) | |
Text
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[4 UNITED STATES g
NUCLEAR REGULATORY COMMISSION ij WASHING TON. D. C. 20555
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NO.112 TO FACILITY OPERATING LICENSE NO. DPR-71 AND AMENDMENT N0.139 TO FACILITY OPERATING LICENSE N0. DPR-62 CAROLINA POWER & LIGHT COMPANY BRUNSWICK STEAM ELECTRIC PLANT, UNITS 1 AND 2 DOCKET NOS. 50-325 AND 50-324 l
1.0 INTRODUCTION
1; By letter of August 28, 1985, Carolina Power & Light Company (CP&L) requested arevisiontotheTechnicalSpecifications(TS)forBrunswickSteam I,'b Electric Plant, Units 1 and 2, which would change the power range over which I
the Rod Block Monitor (RBM) is required to be operable.
The affected l-specifications, for both Brunswick 1 and 2, are the " Applicability" statement I
of TS 3.1.4.3 (Rod Block Monitor) and notes for Tables 3.4.4-1 and 4.3.4-1 i
(concerning control rod withdrawal block instrumentation). These specifications currently require the RBM to be operational "when thermal power is greater than the preset power level of the RWM and RSCS" (Rod Worth Minimizer and Rod SequenceControlSystem). The requested change of August 28, 1985, was to replace the above statement with "when thermal power is greater than or equal to 35% of rated thermal power." As a result of discussions with the staff y
!7 concerning justification of the 35 percent power level, CP&L, in a letter dated May 15, 1987, submitted a revision to the original amendment request l:
of August 28, 1985. The revised proposed amendment would lower the RBM
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operability threshold to 30 percent of rated power.
2.0 EVALUATION
'i The single purpose of the RBM is the mitigation of the Rod Withdrawal Error (RWE)atpowereventb Critical Power Ratio (y blocking rod movement before the safety limit Minimum MCPR) is reached.
It is thus intended for use in the operating power region. The RSCS and RWM are intended solely for mitigation of the Rod Drop Accident (RDA), and are thus for use in the very low "zero" l
pcwer regions in which the RDA could be of significance. That region, based on General Electric and staff consultant analyses, is less than 10 percent power, although most TS, including those of Brunswick 1 and 2, currently require 20 percent power before deactivating the RSCS and the RWM.
j There is no significant technical need for the merging or overlap of these two regions. While a few plants still have TS requiring an overlap, like Brunswick's, most TS, including both older plants and recent )lants using l
standard TS format, do not. These plants generally require tie RWM (and RSCS, if they have it) up to 20 percent power and the RBM above 30 percent power.
Based on previous reviews going back many years, 30 percent power has been established as a reasonable and conservative minimum level for needed RWE mitigation.
The requirement for overlap, when unneeded, could be an l
operational inconvenience and could result in unnecessary delay in power ascent.
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1 The initial CP&L submittal of August 28, 1985,. requesting a 35 percent power-level to activate RBM turn on, led to a staff request for an analysis examining J
this increase over the standard approved. level of 30 percent power. CP&L decided it was more cost effective to alter the request to confonn to the standard rather than generating such a plant specific analysis for Brunswick. The resulting proposal, transmitted by letter dated May 15, 1987 - conforms
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to the standard TS in that an operability threshold for the RBM of 30
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percent power is requested.
i We have reviewed the reports submitted for the proposed changes to the j
L Brunswick 1 and 2 TS for the RBM operability region. Based on this review, the staff concludes that appropriate material was submitted and that the Technical Specification changes, as proposed by the May 15, 1987 submittal, are acceptable.
3.0 ENVIRONMENTAL CONSIDERATION
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These amendments change a requirement with respect to installation or j
ese of a facility component located ~ lthin the restricted areas, as defined in 10 CFR Part 20 and changes to sut ve111ance requirements. The staff has determined that these 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 )reviously issued a proposed finding that these amendments involve no significant nazard consideration,~
and there has been no public coment on such finding. Accordingly, these amend-ments meet the eligibility criteria for categorical er.clusion 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 these amendments.
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4.0 CONCLUSION
l The Comission made a proposed determination that this amendment involves no significant hazards consideration which was published in the Federal Register on September 25, 1985 at 50 FR 38911 and on July 29, 1987 at 52 FR 28373, and consulted with the State of North Carolina. No public
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coments or requests for hearing were received and the State of North Carolina did not have' any coments.
The staff has concluded, based on the considerations discussed above, that: (1) there is reasonable assurance that the health and safety of the-i public will not be endangered by operation in the proposed manner, and (2) such activities will be conducted in compliance with the Comission's 3
regulations, and the issuance of the amendments will-not be inimical to the i
comon defense and security or to the health and safety of the public.
Principal Contributor:
H. Richings Dated: September 24, 1987 l
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