ML20197C099

Submits Rept Re Impact of Changes & Erors in Methodology Used by GE to Demonstrate Compliance W/Eccs Requirements of 10CFR50.46.No Changes or Errors Identified for Safe/Reflood Model Described in NEDE-20566-P-A

ML20197C099
Person / Time
Site:	Cooper
Issue date:	12/18/1997
From:	Graham P NEBRASKA PUBLIC POWER DISTRICT
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NLS970223, NUDOCS 9712240107
Download: ML20197C099 (3)

Text

-

P.O. BOX B EB A 68321 Nebraska Public Power District "Tx%inin"" ,_-___

m_

NLS970223 December 18,1997 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555-0001 Gentlemen:

Subject:

Reporting of Changes and Errors in ECCS Evaluation Models Cooper Nuclear Station NRC Docket 50-298, DPR-46

Reference:

1. Letter RJR-97 084 to USNRC from R. J. Reda (General Electric) dated June 27,1997, " Reporting of Changes and Errors in ECCS Evaluation Models" In accordance with 10 CFR 50.46(a)(3)(ii), the Nebraska Public Power District (District)is herein reporting the impact of changes and errors in the methodology used by General Electric (GE) to demonstrate compliance with the Emergency Core Cooling System (ECCS) requirements of 10 CFR 50.46. Accordingly, there have been no changes or errors identified for the S AFE/REFLOOD model described in NEDE 20566-P-A, " Analytical Model for Loss of Coolant Analysis in Accordance With 10 CFR 30 Appendix K."

llowever, as noted in Reference 1, prior to the reporting requirements of 10CFR50.46, GE increased the manufactured fuel density for all fuels. Since this increased fuel density was a recognized conservatism in the ECCS analysis, there were no changes made to the District's analysis. This conservatism, were it to be implemented in an ECCS analysis would result in a calculated peak cladding temperature (PCT) decrease of 25 degrees Fahrenheit and affects the SAFE /REFLOOD model. At this time, the District is formally recognizing this conservatism and is incorporating it into the current ECCS analysis.

Should you have any questions concerning this matter, please contact me.

Sincerely, PBAL P. D. Graham i Vice President of Nuclear Energy

[i j

/ctm .,;

hA

,,f

~

9712240107 971218 .

f '"'}]f ' til}{l ADOCK 05000278 'V, PDR ". . ,

' Ll-P PDR bbk h h bkNkNNN N N IhDd@ M N8$dN@IN DE5h d bb d p[ "

= _

. , = = ====

b

- t,

+

. ,pt;.

. . j.. , r

, i 4

%LS970223: _

December 18,1997 -i

- Page 2 of 2 y-cc: Regional' Administrator USNRC , Region IV ,

Senior. Project Manager , .

USNRC - NRR Prrject Directorate IV-1 '

Senior Resident Inspector -:

- USNRC

-NPG Distribution ,

~

t e

9 i

'E-I t

1

--..w ,o n . -- , ,, . - . ..,s. -, --r,, , ,e v 4 i,,-y, - , , - -

s. ,el ATTACHMENT 3 LIST OF NRC COMMITMENTS l Cptrespondence No: HLS970223 The following table identifies those actions committed to by the District in this document. Any other actions discussed in the submittal represent intended or planned actions by tF.e District. They are described to the NRC for the NRC's information and are not regulatory commitments. Please notify the Licensing Manager at Cooper Nuclear Statien of any questions regarding this document or any associated regulatory commitments.

COMMITTED DATE COMMITMENT OR OUTAGE The ECCS analysis conservatism, resulting in a calculated peak cladding temperature (PCT) decrease of 25 degrees None.

Fahrenheit, is being incorporated into the current ECCS analysis.

l PROCEDURE NUMBER 0.42 l REVISION NUMBER S l PAGE 9 OF 13 l