ML19347E520

Provides Addl Info Re NUREG-0519,per NRC 810504 Request. Discusses Automatic Depressurization Sys Logic Design Mod & Evaluation of Anticipated Transients W/Single Failure

ML19347E520
Person / Time
Site:	LaSalle
Issue date:	05/06/1981
From:	Delgeorge L COMMONWEALTH EDISON CO.
To:	Schwencer A Office of Nuclear Reactor Regulation
References
RTR-NUREG-0519, RTR-NUREG-519 NUDOCS 8105120330
Download: ML19347E520 (2)

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.~ '- /D Commonwsith Edison t' ) Ona First Natiorr1 Pttra, ChicTgo,11tinois i

O } Address Aeoly to: Post Office Box 767

\ f Chicago, Illinois 60690 y

May 6, 1981 ,

I'N 111981  : l Mr. A. Schwencer, Chief \ . " Magro, Licensing Branch 2 Division of Licensing Q / fg U.S. Nuclear Regulatory Commission //g -

Washington, DC 20555

Subject:

LaSalle County Station Units 1 and 2 Additional Information in Response to NUREG-0519 (0 pen Item 11.e and 11.f)

_NRC-Occket-Nos. 50-373/374 Reference (1): L. 0. DelGeorge letter to A. Schwencer dated May 4, 1981.

Dear Mr. Schwencer:

The purpose of this letter is to clarify information provided in Reference (1) which was submitted to resolve Open Items ll.e and ll.f in NUREG-0519. Specifically, the following informatior. is provided: .

Item 11.e Modification of AOS logic It is the intention of Commonwealth Edison to modify the current LaSalle County ADS logic design by either eliminating the high drywell pressure trip or bypassing the high drywell pressure trip after runout of a timer started at the low perssure ECCS initiation level. In the event the second alternative is chosen, the selection of the time delay setting will be demonstrated by analysis to be appropriate for LaSalle County Station and the results of that analysis will be submitted as a part of the logic modification package. This modifications shall be completed prior to the start of the second fuel cycle on La2alle County Unit 1 and is expected to be completed prior to fuel loading of LaSalle County Unit 2.

Item ll.f. Evaluation of Anticipated Transients-With Single Failure The materials developed by the BWR Owners Group on this subject, summarized in Section L.71 of Appendix L of the LaSalle County FSAR (Am. 56), has been reviewed by Commonwealth Edison and determined to be applicable to and adequate for LaSalle County Station Units 1 and 2.

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In the' event you have.any further quest' ions in this regard, please-direct them to this. office.

Very truly yours,

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[m L.Nuclear O. De1 Licensing George Administrator cc: NRC' Resident Inspector - LSCS

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