ML20091B584
| ML20091B584 | |
| Person / Time | |
|---|---|
| Site: | Monticello  |
| Issue date: | 09/15/1977 |
| From: | Mayer L NORTHERN STATES POWER CO. |
| To: | Stello V Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML20091B589 | List: |
| References | |
| NUDOCS 9106100522 | |
| Download: ML20091B584 (2) | |
Text
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NSIB HOMTHEMN STATES POWEM COMPANY uiNNs Apo u s. MIN N E GOTA 99404 September 15, 1977
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9 Hr Victor Stello, Director Division of Operating Reactors
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c/o Distribution Services Branch, DDC, AIH g
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11 S Nuclear ReguFatory Cocuission Washington, DC 20555 g/
/
//
Dear Mr Stellot k
MONTICELLO INCLEAR GENERATING PIANT Docket No. 50-263 License No. DPR-22 Filing of ECCS Analysis On February 18, 1977, we sulaitted a letter stating that we would provide a re-evaluation of the loss of coolant accident for Monticello incorporating ECCS model changes which vere under discussion at that time.
Our voluntary cocuitnent was confitned by a Nuclear Regulatory Commission Order dated March 11, 1977.
The attached doctanent entitled, " Loss of Coolant Accident Analysis Report for Monticello Nuclear Generating Plant, NEDO 24050, September,1977" fulfills the cocuitments of the two above referenced docu-ments.
'Ihe litnitations resulting from the new evaluation are in general less re-strictive than those in the existing technical specifications. There are, however, points where the newly calculated limits are slightly more restrictive than those in the technical specifications for the fuel types in service at Monticello. As has been the practice in such situations in the past, ve will adhere to the most limiting of the present technical specifications and the 4
newly calculated limits until our technical specifications are appropriately i
revised.
A formal license amendment request is in preparation, and will be sulnitted shortly.
'Ihe ECCS model previously approved in accordance with 10 CPR 50 Appendix K, was applied to a variety of specific break sizes to determine the response for the spectrum from a small break to the DBA break size. Additional break aires i
have been analyzed to better define the response over the full spectrtun of break sizes using the currently approved ECCS model. This additional analysis has identified 407. of the DBA area as being slightly more severe than the full DBA area upon which limits were previously based.
Yours very truly, L 0 Mayer, PE l
Manager of Nuclear Suppori Services cc:
J G Keppler, G Charnoff, MPCA, Attn J W Teruan l
9106100522 770915 7MMO I
PDR ADOCK 05000263 P
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