ML20101U419

Supplement to 10CFR50.59 Annual Rept, for Period Ending 920331,consisting of Info Re end-of-life Moderator Temp Coefficient for Cycle 5

ML20101U419
Person / Time
Site:	Callaway
Issue date:	03/31/1992
From:	UNION ELECTRIC CO.
To:
Shared Package
ML20101U417	List: ML20101U415 ML20101U419
References
NUDOCS 9207230003
Download: ML20101U419 (2)

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. Attachment to ULNRC-26 6 3 Supplement to 10 CFR 50.59 Safety Evaluation Summary Report for Callaway Nuclear Plant RrR-07558J End-of-Life Moderator Temperature Coefficient for Cycle S The RFR extends the end-of-life (EOL) moderator temperature

-coefficient (MTC) limit for Cycle 5. Justification for extended range was performed by utill:1ng available margin in reactor vendor calculations. In order to further extend the range of acceptable EOL_MTC surveillance measurements, non LOCA safety ana)yses which use the most negative MTC as part of the conservative. input assumptions have been evaluated.

Overall protection system design is unchanged from that included in accident analyses in FSAR Chapter 15, in analysis of superheated blowdowns outside containment, and in analysis of Environmental Allowance Modifier / Trip Time Delay. There are no impacts on the LOCA and non-LOCA transient analyses documented in FSAR Chapter 15. Design of plant protection systems and the intended manner of. plant operation are unchanged. The Bases for Technical Specification 3/4.1.1.3 ensure that the most negative MTC' limit specified in the COLR, corresponding to the most pos3tive. moderator density coefficient, is not exceeded. There le to change to peaking factor limits or to the safety analysis DNbR limit. The revised EOL MTC limit has no effect on the

.results presented in FSAR 15.6.5 and the peak clad temperature remains below the ECCS Acceptance Criteria limit, i

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9207230003'920715 DR ADOCK05000g83

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4 cc: T. A. Baxter, Esq.

Shaw, Pittman, Potta & Trowbridge Wa hington D C. 2 b37 Dr. J. O. Cermak CFA, Inc. >

18225-A Flower (113 Way Gaithersburg, MD 20079-5334 R. C. Knop +

Chief, Reactor Project Branch 1 U.S. Nuclear Regulatory Commission Region III 799 Roosevelt Road Glen-Ellyn, Illinois 60137 Bruce Bartlett Callaway Resident Office U.S. Nuclear Regulatory Commission RR#1 Steedman, Missouri 65077 L. R. Wharton (2)

Office'of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission 1 White Flint, North, Mail Stop 13E21 11555 Rockville. Pike Rockville, MD 20852 Manager, Electric Department Missouri Public Service Commission P.O. Box 360 Jefferson City, MO 65102 l[

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