ML19263C641
| ML19263C641 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 02/21/1979 |
| From: | Mayer L NORTHERN STATES POWER CO. |
| To: | Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML19261B638 | List: |
| References | |
| NUDOCS 7902280307 | |
| Download: ML19263C641 (1) | |
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NSP NORTHERN STATES POWER COMPANY M S N N E A PO Ll e. MIN N E S OTA 55401 February 21, 1979 Director of Nuclear Reactor Regulation U S Nuclear Regulatory Commission Washington, DC 20555 PRAIRIE ISLAND NUCLEAR GENERATING PIANT Docket No. 50-282 License No. DPR-42 50-306 DPR-60 ECCS Reanalysis
References:
(a)
Letter, L 0 Mayer (NSP) to Director, Nuclear Reactor Regulation (NRC), April 10, 1978 (b)
" Westinghouse ECCS Evaluation Model, February 1978 Version", WCAP-9221 (nonproprietary), February 1978 Attached are forty copies of the revised ECCS analysis, submitted in response to the Order for Modification of Licenses, dated May 18, 1978.
The analysis presented in the attached report was performed using the February, 1978 version of the Westinghouse ECCS Evaluation Model as approved by the NRC on August 23, 1978. The " February 1978" model includes the following model improve-ments:
(1) water packing, (2) modeling of paint on containment walls, (3) improved FLECHT correlation, and (4) dynamic steam cooling as described in Reference (b).
In addition, the attached analysis corrects the zircaloy-water logic inconsistency reported in Reference (a).
The attached report includes the analysis for the limiting large break loss of coo lant ac cide nt (0.4 DECLG). This break was determined to be limiting based on generic sensitivity studies for a typical 2-loop plant with 14x14 fuel (included as Appendix A of the report ).
h-L 0 Mayer, PE Manager of Nuclear Support Services LOM/JAC/ak cc:
J G Keppler G Charnof f 7002280307