TXX-6444, Responds to Generic Ltr 86-16, Westinghouse ECCS Evaluation Models. ECCS Reanalysis for Unit 1 Not Required.Loca Analysis for Unit 2 Performed w/1981 Version of Westinghouse ECCS Model Using Wreflood W/O Bart & Acceptable
| ML20214J338 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 05/18/1987 |
| From: | Counsil W, Keeley G TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| To: | NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM) |
| References | |
| GL-86-16, TAC-R00174, TAC-R174, TXX-6444, NUDOCS 8705280013 | |
| Download: ML20214J338 (2) | |
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t)
M Log # TXX-6444
=M File # 10010 4
915.6 E
E Ref: 10CFR50.46 nIELECTRIC II"lNN,an, May 18, 1987 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D': 20555
SUBJECT:
COMANCHE PEAK STEAM ELECTRIC STATION (CPSES)
DOCKET NOS. 50-445 AND 50-446 WESTINGHOUSE ECCS EVALUATION MODELS GENERIC LETTER 86-16 Gentlemen:
TU Electric has reviewed Generic Letter 86-16, " Westinghouse ECCS Evaluation Models", for applicability to CPSES and has determined the following:
CPSES Unit 1 - The LOCA analysis was performed with the February,1978 version of the Westinghouse ECCS Evaluation Model using WREFLOOD.
Westinghouse has concluded that the error in the 1978 model using WREFLOOD results in a 6-120F underprediction of peak clad temperature (PCT). Westinghouse has also concluded additional PCT margin is available through updating the heat transfer models in WREFLOOD.
This additional margin would more than offset the 6-120F increase in PCT. The calculated PCT for the CPSES Unit 1 LOCA analysis is 2010.70F, well below the 10CFR50.46 limit of 22000F, TV Electric concurs with Generic Letter 86-16 in that an ECCS reanalysis is not required.
CPSES Unit 2 - The LOCA analysis was performed with the 1981 version of the Westinghouse ECCS Evaluation Model using WREFLOOD, but not using BART. Westinghouse has determined that the error in PCT from the 1981 model using WREFLOOD without BART is also 6-120F underpredicted. The predicted PCT for CPSES Unit 2 LOCA analysis is 18080F. TU Electric has determined that an ECCS reanalysis is not required due to the sufficient PCT margin between the Unit 2 analysis of 18080F and the 10CFR50.46 limit of 22000F.
However, TU Electric is still preparing the CPSES Unit 2 FSAR amendment for optimized fuel assemblies which includes this analysis. As we understand Generic Letter 86-16, the 1981 version of the Westinghouse ECCS Evaluation Model using WREFLOOD without BART is acceptable to support the planned future licensing action (FSAR amendment) of CPSES Unit 2.
0705200013 070510 PDR ADOCK 05000445' I
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A PDR M brth Olne Street I..It Mi l)allas, leus 73311 0
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.May 18, 1987 Paga 2 Please notify us if you do not agree with our assessment of Generic Letter 86-16 as it applies to CPSES Unit I and the future CPSES Unit 2 FSAR submittal.
Very truly yours, N
W. G. Counsil By:
I G. S. Keeley
/
Manager, Nuclear Lipsing JDS/mlh c - Mr. R. D. Martin, Region IV Mr. D. L. Kelley, RI
-Region IV Mr. H. S. Phillips, RI - Region IV
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