ML20056D492

Safety Evaluation Re Fuel Reconstitution

ML20056D492
Person / Time
Site:	Byron
Issue date:	07/27/1993
From:	Office of Nuclear Reactor Regulation
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ML20056D491	List: ML20056D489 ML20056D492
References
NUDOCS 9308160375
Download: ML20056D492 (3)

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& ) (. E UNITED STATES i'  ! NUCLEAR REGULATORY COMMISSION WASHINGTON. D.C. 20555-4001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REGULATION RELATED TO THE TECHNICAL EVALUATION OF FUEL RECONSTITUTION COMMONWEALTH EDISON COMPANY BYRON STATION. UNIT NO. I DOCKET NO. STN 50-454 1.0 INTRODUCf10N By letter dated March 16, 1993 (Reference 1), Commonwealth Edison Company (Ceco, the licensee) transmitted their reload safety evaluation (RSE) process for the substitution of a single stainless steel filler rod for a failed fuel rod in one fuel assembly for Byron Station, Unit 1. This reconstitution permits the original fuel assembly to be reused in Cycle 6 without requiring a reload core redesign during the current refueling outage and the selection of a replacement fuel assembly.

Supplement 1 of Generic Letter (GL) 90-02, " Alternative Requirements for Fuel Assemblies in the Design Features Sectian of Technical Specifications,"

July 31, 1992 (Reference 2) recognizes the acceptability of the use of reconstituted fuel assemblies including inert filler rods. These reconstitutions may be performed under the provisions of 10 CFR 50.59 provided that the required safety analyses are performed with NRC staff-approved methodologies which are applied to assembly configurations that lie within the scope of the reviewed fuel lattice configurations.

In Reference 1, the licensee also informed the staff of a non-related minor Cycle 6 core redesign in order to replace three damaged fuel assemblies with less reactive assemblies.

2.0 EVALUATION The licensee intends to use a single inert filler rod of stainless steel to replace one failed fuel rod for reconstituting a VANTAGE-5 fuel assembly G74F, which is a once-burned assembly from Cycle 5, with an approximate burnup of 22.6 GWD/MTU. The failed rod was located at assembly lattice location B6.

Assembly G74F is scheduled for re-insertion in Cycle 6 at peripheral core location F-01. The licensee stated that RSE analyses of the reconstitution -

was performed, in order to comply with all safety design baser, according to the NRC approved methodologies (Reference 3) including the Westinghouse fuel reconstitution topical report WCAP-13060 (Reference 4) which was recently approved (Reference 5). Based on the guidance furnished in Supplement I to 1 GL 90-02, the licensee RSE approach is consistent with the requirenents  !

described and, therefore, is acceptable for Byron, Unit 1, Cycle 6.

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' l 3.0 TECHNICAL SPECIFICATION REQUIREMENT The current Byron, Unit 1, Technical Specifications (TS) were examined to ensure that they are consistent with the model TS of GL 90-02, Supplement 1.

TS Section 5 - Desian Features o TS Section 5.3 Reactor Core, Fuel Assemblies The current Byron, Unit 1, TS Section 5.3.1 includes wording consistent with the model TS contained in GL 90-02, Supplement 1, as follows:

" Limited substitutions of zirconium alloy or stainless steel filler rods for fuel rods, in accordance with NRC-approved applications of fuel rod configurations, may be used. Fuel assemblies shall be limited to those fuel designs that have been analyzed with applicable NRC staff-approved codes and methods, and shown by tests or analyses to comply with all fuel safety design bases. A limited number of lead test assemblies that have not completed representative testing may be placed in non-limiting core regions."

Based on the above, we conclude that the proposed fuel reconstitution is permitted by the current TSs.

4.0 CONCLUSION

The staff reviewed the March 16, 1993, letter for the Byron, Unit 1, Cycle 6 fuel assembly reconstitution. Based on our evaluation, we find the revised RSE process used by the licensee for the fuel assembly reconstitution safety analyses to be acceptable.

Principal Contributor: E. Kendrick, SRXB, DSSA Date: July 27, 1993

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5.0 REFERENCES

1. Letter from J. A. Bauer (CECO) to T. E. Murley (NRC), " Byron Station Unit 1 Cycle 6 Fuel Assembly Reconstitution," March 16, 1993.

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2. Supplement I to Generic Letter 90-02, " Alternative Requirements for Fuel Assemblies in the Design Features Section of Technical Specifications,"

July 31, 1992.

3. WCAP-9272-P-A, " Westinghouse Reload Safety Evaluation Methodology,"

Westinghouse Electric Corporation, July 1985.

4. WCAP-13060-P, " Westinghouse Fuel Assembly Reconstitution Evaluation Methodology," Westinghouse Electric Corporation, Commercial Nuclear Fuel ,

Division, September 1991.

5. Letter from A. C. Thadani (NRC) to S. R. Tritch (W), " Acceptance for Referencing of Topical Report WCAP-13060-P, ' Westinghouse Fuel Assembly .

Reconstitution Evaluation Methodology,' (TAC No. M82139)," March 30,1993.

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