ML20210A558
| ML20210A558 | |
| Person / Time | |
|---|---|
| Site: | Byron  |
| Issue date: | 05/01/1987 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20210A551 | List: |
| References | |
| NUDOCS 8705050112 | |
| Download: ML20210A558 (3) | |
Text
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'o UNITED STATES
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~,j NUCLEAR REGULATORY COMMISSION r,;
aj WASHINGTON, D. C. 20555
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 7 TO FACILITY OPERATING LICENSE NO. NPF-37 AND AMENDMENT NO. 7 TO FACILITY OPERATING LICENSE N0. NPF-66 COMMONWEALTH EDIS0N COMPANY BYRON STATION, UNITS 1 AND 2 C0CKET NOS. STN 50-454 AND STN-50-455 INTRODUCTION In a letter dated January 6,1987 the licensee requested a change to Technical Specification Section 5.3.1, Design Features - Fuel Assemblies. The change would allow for reconstitution of fuel assemblies by insertion of filler rods fabricated from Zircaloy-4 or stainless steel or by leaving vacancies.
The licensee's submittals of March 4 and March 23, 1987, were made as a result of NRC staff request to clarify the original submittal and do not contain substantive changes.
EVALUATION The intent of the proposed change is to allow for the reduction in the number of fuel rods per assembly in cases where leaking fuel rods can be identified and replaced with Zircaloy-4 or stainless steel rods or vacancies.
Replacement of leaking fuel rods with other fuel rods involves handling of additional fuel assemblies and has not been used in Westinghouse reactors to date. Replacement of leaking fuel rods will permit utilization of the energy remaining in fuel assemblies containing defective fuel rods.
In general, substitution of a limited number of fuel rods with filler rods or water holes has a negligible effect on core physics parameters and consequen+1y on the safety analysis. The licensee states that in each reload core the reconstituted assemblies will be evaluated using approved methods.
The reload analysis will ensure that the safety criteria and design limits, including peaking factors and core average linear heat rate effects, are not exceeded. Thus, the final safety evaluation of implementation of substitutions allowed by this change will be made as part of the reload analysis performed for the affected cycle.
8705050112 870501 PDR ADOCK 05000454 P
. We had earlier approved a similar request at another facility for a change to Technical Specification 5.3.1 with slightly different wording than proposed by the licensee which we prefer and wish to standardize. This wording is "The reactor core shall contoin 193 fuel assemblies with each fuel assembly ncrmally containing 264 fuel rods clad with Zircaloy-4, except that limited substitution of fuel rods by filler rods consisting of Zircaloy-4 or stainless steel or by vacancies may be made if justified by a cycle specific reload analysis." This wording was discussed with the Commonwealth Edison staff and they orally agreed on February 4, 1987. With this modification, we find the proposed change acceptable.
The licensee's proposal to reconstitute nuclear fuel on site posed the possibility of undue occupational radiation exposure.
By letter dated February 11, 1987 we asked several questions concerning radiation protection provisions for these operations. The licensee responded by letter dated March 4,1987. The licensee's planned radiation protection coverage includes continuous health physics technician coverage, health physics supervision review each shift, alarming radiation and contamination equipment, underwater dose rate equipment, enhanceo contamination control measures and minimization of non-essential observers. The reactor will be subcritical for approximately 30 days before reconstitution starts. We reviewed the response and concluded that generally the appropriate steps were being taken to keep occupational exposure as low as is reasonably achievable (ALARA).
However, experience elsewhere suggested that these operations might need special precautions to control radiologically " hot" particles. This potential-problem was discussed with the licensee ano the licensee's response was documented by letter dated March 23, 1987. Enclosed with the letter was a list of radiation guidelines to be followed during reconstitution activities. These guidelines include surveying workers for hot particles prior to removing the outer and inner protective clothing, and checking worker outer protection clothing for particles whenever work is going on and items are being handled or put into or taken out of the fuel pool. We have reviewed this response and conclude that the licensee is utilizing the experience at San Onofre and otherwise taking the appropriate actions to control possible radioactive particles. Thus, we conclude that the radiation protection provisions are appropriate for compliance with the criterion "as low as is reasonably achievable" (ALARA) and, therefore, are acceptable.
Because the limited substitution of Zire.aloy-4 or stainless steel rods of vacancies for fuel rods is not expected to have a significant impact on plar.t safety, because the radiation protection provisions while performing reconstitution are appropriate for compliance with ALARA, and because a cycle specific evaluation will be performed to justify any such substitutions with an acceptable evaluation model, we find the proposed Technical Specification change for Byron, Units 1 and 2, with the modifications as discussed above, acceptable.
.. ENVIRONMENTAL CONSIDERATION These amendments involve a change in the installation or use of the facilities components located within the restricted areas as defined in 10 CFR 20. 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 Commission has previously issued a proposed finding that these amendments involve no sionificant hazards consideration and there has been no public comment on such finding. Accordingly, these amendments meet the eligibility criteria for categorical exclusion set forth in 10 CFR Sec 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.
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, and (2) 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.
Dated: May 1, 1987 PRINCIPAL CONTRIBUTORS:
B. Mann L. Olshan C. Willis i
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