ML19257C664

Responds to NRC Request for Further Calculations Re Fuel Clad Swelling to Demonstrate Continued Compliance W/Eccs Acceptance Criteria.Encl C-E Analysis Demonstrates Compliance w/10CFR50.46 Limits

ML19257C664
Person / Time
Site:	Arkansas Nuclear
Issue date:	01/25/1980
From:	Trimble D ARKANSAS POWER & LIGHT CO.
To:	Eisenhut D Office of Nuclear Reactor Regulation
Shared Package
ML19257C665	List: ML19257C664
References
2-010-20, 2-10-20, NUDOCS 8001290567
Download: ML19257C664 (3)

Text

. n, a ARKANSAS POWER & LIGHT COMPANY

' POST OFFICE box 551 LITTLE ROCK, ARKANSAS 72203 (501) 371-4000 January 25, 1980 2-010-20 Mr. D. G. Eisenhut, Acting Director Division of Operating Reactors Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Cormission Washington, D. C. 20555

Subject:

Arkansas Nuclear One - Unit 2 Docket No. 50-368 License No. NPF-6 Fuel Clad Swelling (File: 2-1510)

References:

(A) NRC letter from D. G. Eisenhut to all Operating Light Water Reactors, dated November 9, 1979 (B) AP&L letter to D. G. Eisenhut from W. C. Cavanaugh, dated January 7, 1980 (C) Enclosure 1-P of C-E Letter LD-78-069, A. E. Scherer to D. F. Ross, dated September 18, 1978

Dear Mr. Eisenhut:

Reference A required confirmation of information presented by the fuel vendors regarding fuel cladding strain and assembly flow blockage model-ing in our ECCS analyses. Confirmation of our continued compliance with the Appendix K requirements was provided in Reference B. Reference B also stated that regions exist where the fuel cladding strain and assem-bly flow blockage models used in the ECCS analyses for ANO-2 are less conservative than the new NRC models. As requested, further calculations were initiated to demonstrate continued compliance with the ECCS Accept-ance Criteria of 10CFR50.46.

In order to respond to the NRC concern in a timely manner, Combustion Engineering (C-E), our fuel vendor, performed an analysis for the oper-ating plants with C-E fuel. The attached analysis was performed for the plant most limited by the new NRC models for the previously determined limiting break size. The C-E ECCS Evaluation Model of Reference C was used for this analysis. The method for including the new NRC rupture strain and blockage models is described in detail in Section III of the attached report. Results of the analysis are summarized in Section IV of the report. With higher (more conservative) strain and blockage, a lower peak cladding temperature than calculated for the reference cycle was obtained. The applicability of the analysis to ANO-2 is provided in Sections V and VI.

P M . OUTH UTILITIES SYSTEM

Mr. D. G. Eisenhut January 25, 1980 As a result of the analysis documented in the attached report, we believe that the ECCS analyses performed for our plant (s) by C-E continue to be in compliance with the limits of 10CFR50.46.

Very truly yours, bauS0$.Y David C. Trimble Manager, Licensing DCT:M0W:skm Attachment 1829 236

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