ML20133N244
| ML20133N244 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 08/05/1985 |
| From: | Musolf D NORTHERN STATES POWER CO. |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| RTR-NUREG-0737, RTR-NUREG-737, TASK-2.K.3.31, TASK-TM NUDOCS 8508130418 | |
| Download: ML20133N244 (1) | |
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Mr Northern States Power Company 414 Nico!!et Mail Minneapous Minnesota 55401 Teephone 16121330-5500 August 5,1985 Director Office of Nuclear Reactor Regulation U S Nuclear Regulatory Commission Washington, DC 20555 PRAIRIE ISLAND NUCLEAR GENERATING PLANT Docket Nos. 50-282 License Nos. DPR-42 50-306 DPR-60 Resolution of NUREG 0737 Item II.K.3.31 Your letter dated June 6,1985 notified us of the approval of the NOTRUMP model for small break LOCA analysis. As you correctly noted, we are members of the Westinghouse Owners Group (WOG) and plan to use the NOTRUMP model to analyze the small break LOCA for Prairie Island. Since a new small break analysis was planned to be done for Prairie Island prior to Unit 1 Cycle 11 operation, we will submit a Prairie Island specific analysis this fall rather than using the WOG " generic" submittal.
Since we will be using both Westinghouse and Exxon fuel beginning in the spring of 1986, both fuel types will be analyzed. The NOTRUMP model consists of two codes; a system code--NOTRUMP and a fuel response code--
LOCTA. Westinghouse fuel parameters will be used to run the NOTRUMP code.
Two fuel response analyses, one for Westinghouse and one for Exxon fuel, will then be performed with the LOCTA code. Hydraulically, the two fuel types are very similar--differing by 3.4% in pressure drop and 6% in flow area. Differences of thin magnitude have little impact on the small break hydraulics which are primarily system controlled. In addition, similarities in the fuel rod designs ensure that decay heat will be nearly identical for the two fuel types. Differences such as pellet to clad gap will be accounted for in the LOCTA analysis. Therefore, the hydraulic output from the NOTRUMP code (having Westinghouse fuel inputs), can be used as input to the LOCTA analysis of the Exxon fuel.
Please contact us if you have questions concerning this issue.
8 U David Musolf Manager - Nuclear Suppor Services
[' h DMM/TMP/tp O
c: Regional Administrator-III, NRC NRR Project Manager, NRC i
t 0 Resident Inspector, NRC 2
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