ML20071B448
| ML20071B448 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 02/22/1983 |
| From: | Fay C WISCONSIN ELECTRIC POWER CO. |
| To: | Clark R, Harold Denton Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML120170214 | List: |
| References | |
| NUDOCS 8302280310 | |
| Download: ML20071B448 (3) | |
Text
a l%sconsin Elecinc eomcoww 231 W. MICHIGAN, P.O. BOX 2046, MILWAUKEE, WI 53201 February 22, 1983 Mr. H. R. Denton, Director Office of Nuclear Reactor Regulation U.
S. NUCLEAR REGULATORY COMMISSION Washington, D.
C.
20555 Attention:
Mr.
R. A. Clark, Chief Operating Reactors Branch 3 Gentlemen:
DOCKET NOS. 50-266 AND 50-301 EMERGENCY CORE COOLING SYSTEM ANALYSES SPECIFICALLY TREATING UPPER PLENUM INJECTION POINT BEACH NUCLEAR PLANT, UNITS 1 AND 2 In Mr. Clark's letter of November 8, 1982 you requested the submittal on our dockets of the Emergency Core Cooling System (ECCS) evaluation model which specifically treats upper plenum injection (UPI) including "a set of sample calculations encompassing a spectrum of large-break LOCAs".
In our letter to you dated December 10, 1982 we referenced Westinghouse Electric Corporation letter No. NS-TMA-2172 dated December 6, 1979 for the description of the modifications to the Westinghouse ECCS Evaluation Model which specifically treat UPI for Point Beach Nuclear Plant, Units 1 and 2.
The attachment to this letter contains the results of the ECCS large-break LOCA analysis of Point Beach, Unit 1, with Westinghouse optimized fuel using the Westinghouse 1981 Evaluation Model modified to account for-UPI.
The results indicate a 151*F l
benefit in calculated Peak Clad Temperature (PCT) for the UPI base l
case (30% core coverage) in comparison to the non-UPI case.
The l
results were computed for the 0.4 double-ended cold leg LOCA l
blowdown transient rather than a spectrum of large-break LOCAs because this case has historically been limiting for two-loop plants.
1 i
8302280310 830222 PDR ADOCK 05000266 p
b
+
Mr. H.
R.
Denton February 22, 1983 The attachment also contains the results of sensitivity studies regarding the percentage of core coverage achieved by UPI.
The results indicate a 146"F benefit, a 60'F benefit, and a 130'F penalty in PCT for 50%, 70%, and 100%,'respectively, of core coverage with UPI water.
However, Westinghouse has concluded, based on test results included in the 1979 letter, that 30% of core coverage by UPI water is an upper bound for Point Beach.
Attached to an NRC letter to us dated June 27, 1978 was
" Safety Evaluation Report on Interim ECCS Evaluation Model for Westinghouse Two-Loop Plants".
This SER imposed an interim 60*F PCT penalty on Point Beach for the effects of UPI compared to the results of_the large-break LOCA analyses using the standard Westinghouse ECCS evaluation Model.
Based on the results of the attached UPI analyses, it is requested that a final SER be prepared promptly so that this interim 60*F PCT penalty can be removed.
It is our intention to perform future large-break LOCA-analyses using the standard Westinghouse ECCS Evaluation Model, which has now been shown by~the attached report to be conservative with respect to the effects of UPI phenomena.
We would be pleased to answer a5y questions you may have regarding this information.
Very truly yours, du"'t/-
Vice President - Nuclear Power C. W. Fay Attachment Copy to NRC Resident Inspector
)
IED file CFy
^
- n swees Westinghouse WaterReactor Electric Corporation Divisions Box 2728 Pmsburgh Pennsylvania 15230 February 18, 1983 WEP-83-515 Mr. D. K. Porter, Superintendent Nuclear Engineering Section Wisconsin Electric Power Company 231 West Michigan Street Milwaukee, WI 53201 Wisconsin Electric Power Company Point Beach Units 1 and 2 l
Final Report - UPI l
l
Dear Mr. Porter:
Attached is the final report on the Point Beach LOCA results obtained by j
using the Westinghouse 1981 Evaluation Model modified to account for l
upper plenum injection. Comparisons with a non-UPI case and the results j
of the core coverage sensitivity study are also included in this report.
If there are any questions, please call C. C. Sprumont at (412) 256-5409.
Yours very truly, f}&y ;;.- N W.
hnson, Manager Operating Plant Projects l
Mid-America Region s
CCS/j Encl.
cc: J.J.Zach,}L C. W. Fay, IL H. Hanneman, IL C. A. Lins, IL - W N
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