ML20209D001

Application for Amends to Licenses NPF-2 & NPF-8,changing Tech Specs to Increase Steam Generator Tube Plugging Limit to 10% & Heat Flux Hot Channel Factor Limit.Fee Paid

ML20209D001
Person / Time
Site:	Farley
Issue date:	08/25/1986
From:	Mcdonald R ALABAMA POWER CO.
To:	Rubenstein L Office of Nuclear Reactor Regulation
Shared Package
ML20209D006	List: ML20209D001 ML20209D026 ML20209D039
References
62283, TAC-62283, TAC-62284, NUDOCS 8609090163
Download: ML20209D001 (3)

Text

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• C'alling Address Altbirns Power Company 600 North 18th Street Post Office Box 2641 Birmingham, Alabama 35291 Telephone 205 783-6090 R. P. Mcdonald Senior Vice President Flintridge Building M3b3lll3NW6

? e se nm evc : 5, rre-August 25, 1986 Docket Nos. 50-348' 50-364 Director, Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, D. C. 20555 Attention: Mr. L. S. Rubenstein Gentlemen:

Joseph M. Farley Nuclear Plant - Units 1 and 2 Proposed Steam Generator Tube Plugging Limit and Heat Flux Hot Channel Factor Technical Specification Changes Farley Nuclear Plant currently has a steam generator tube plugging limit of 5% as shown on Technical Specification Figure ?,1-1. This limit is based on the Large Break LOCA/ECCS analysis in the FSAR Section 15.4 which assumes 5%

I steam generator tube plugging. Approximately 2.9% of the steam generator tubes have been plugged in Unit 1 and approximately 3.7% of the steam j

generator tubes have been plugged in Unit 2. This level of steam generator tube plugging includes all row 1 tubes in each steam generator. The 5%

technical specification limit is anticipated to be adequate for any tube plugging which may be required as a result of tube inspections performed in the next refueling outage for each unit. However, Alabama Power Company does not want to risk a potential delay of plant startup due to this technical specification limit should more tubes require plugging than ,

currently anticipated. Therefore, a technical specification change is l proposed to increase the steam generator tube plugging limit to 10% in order to provide additional margin to the limit. A change to the Heat Flux Hot Channel Factor (F ) limit of Technical Specification 3.2.2 from 2.31 to 2.32 l- for greater than 50% Rated Thermal Power (RTP) and from 4.62 to 4.64 for less than or equal to 50% RTP is also proposed. The proposed technical

specification changes to the tube plugging limit and F are provided in l' Attachment 1.

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Mr. L. S. Rubenstein August 25, 1986 U. S. Nuclear Regulatory Commission Page 2 Alabama Power Company has determined that the proposed changes do not involve a significant hazards consideration. In accordance with 10CFR50.92, a significant hazards evaluation is provided as Attachment 2.

To support these proposed changes to the Technical Specifications, Westinghouse has perfonned the required Large Break LOCA analysis utilizing the Westinghouse 1981 ECCS Large Break Evaluation Model with BART for Alabama Power Company. A description of this analysis, including the methodology, assumptions, references and results, is provided in Attachment 3. This new analysis assumes an F of 2.32 to be consistent with the original Large Break LOCA Analysis and design / licensing basis for Farley Nuclear Plant. The present F limit of 2.31 for greater than 50% RTP and 4.62 for less than or equal to 50% RTP was required as a result of penalties assessed by the NRC against the 1978 version of the Westinghouse ECCS Evaluation Model. The new analysis has calculated a worst-case peak clad temperature (PCT) of 1973 F and confirms that the Farley Nuclear Plant ECCS cooling performance meets the acceptance criteria of 10CFR50.46.

Alabama Power Company recognizes that Westinghouse has notified the NRC by letter NS-NRC-86-3130 dated June 2,1986 of an assessment regarding the effe ts of control rod thimble filling during the reflood phase and the removal of a hot assembly power adjustment, originally included to account for control rod thimbles, from the BART code methodology. As discussed in the Westinghouse notification and further described in WCAP-9561-P-A, Addendum 3, the effect of thimbles on core hydraulics and the removal of the inappropriately applied hot assembly power adjustment was found to be offset by conservatisms currently contained in BART. This generic assessment of the model changes described in WCAP-9561-P-A, Addendum 3 is applicable to the Farley Nuclear Plant analysis documented in Attachment 3. Additional studies have subsequently been performed by Westinghouse which have shown that a revised BART analysis which incorporates the required model changes and removes some of the identified conservatisms should result in a reduction in PCT. However, even if this revised analysis predicted an increase in PCT, the PCT would still remain well within the 10 CFR 50.46 acceptance criterion of 2200*F. Alabama Power Company further recognizes that the resolution of the required model changes is subject to NRC review and approval.

An additional analysis has been performed to determine the effects on core flow due to steam generator tube plugging. This analysis determined that 10%

steam generator tube plugging will not decrease RCS flow below the thermal design flow (TDF) for Farley Nuclear Plant. Since the non-LOCA transients are based on TDF, a 10% steam generator tube plugging limit was determined to have no impact on the non-LOCA transients and therefore no impact on DNB.

The proposed change in F is also within the bounds of the assumptions of the non-LOCA transient analyses and has no impact on these analyses.

Furthermore, RCS structural integrity is not impacted by the increase in steam generator tube plugging.

Mr. L. S. Rubenstein August 25, 1986 U. S. Nuclear Regulatory Commission Page 3 Alabama Power Company's Plant Operations Review Committee has reviewed these proposed changes and the Nuclear Operations Review Board will review these l proposed changes at a future meeting. It is requested that these proposed changes be approved by November 3,1986.

Pursuant to 10CFR170.21, the required License Amendment Application Fee of

$150.00 is enclosed. In accordance with 10CFR50.90, three signed originals and forty copies of these proposed changes are en.:losed. A copy of these  ;

proposed changes nas also been sent to Dr. C. E. Fox, the Alabama State '

Designee, in accordance with 10CFR50.91(b)(1).

If there are any questions, please advise.

Respectfully submitted, ALABAMA POWER COMPANY i

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[kv' R. P. Mcdonald (

RPM / JAR: dst-T.S.6 Attachments cc: Mr. L. B. Long SWORN TO AND SUBSCRIBED BEFORE ME Dr. J. N. Grace (

Mr. E. A. Reeves THIS nh2 DAY OF //4russi , 1986

M:%adford k

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i Notary P(ylic My Commi ion Expires: 7-/[-fM i

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