NLS2011095, 10 CFR 50.46(a)(3)(ii) Report
| ML11270A097 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 09/21/2011 |
| From: | Vanderkamp D Nebraska Public Power District (NPPD) |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NLS2011095 | |
| Download: ML11270A097 (3) | |
Text
N Nebraska Public Power District Always there when you need us 50.46 NLS2011095 September 21, 2011 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555-0001
Subject:
10 CFR 50.46(a)(3)(ii) Report Cooper Nuclear Station, Docket No. 50-298, DPR-46
Dear Sir or Madam:
The purpose of this letter is for Nebraska Public Power District to submit a 30-day report identifying errors in the methodology used to demonstrate compliance with the Emergency Core Cooling System requirements of 10 CFR 50.46. GE Hitachi informed Cooper Nuclear Station (CNS) via Notification Letters 2011-02 and 2011-03, dated September 2, 2011, that a rise in calculated Peak Cladding Temperature (PCT) of more than 50'F exists.
GE Hitachi Notification Letter 2011-02 identified that the input coefficients used to direct the deposition of gamma radiation energy produced by fuel, caused the heat deposited in the fuel channel (post-scram) to be over-predicted and the corresponding heat to the fuel to be under-predicted. This error applies to GE14 10xl0 fuel and the impact to CNS is 35'F.
GE Hitachi Notification Letter 2011-03 identified an error in the input formulation for gamma heat deposition to the channel wall for 9x9 and 1Oxl 0 fuel bundles. The energy distribution during the pre-scram phase was updated with the appropriate energy distribution. This error applies to GE14 1Oxl0 fuel and the impact to CNS is 95 0F.
The cumulative effect of the errors is 130'F. The previous PCT was 2040'F. The errors reported by GE Hitachi increased this value to 21700F. The new PCT of 2170'F is below the 10 CFR 50.46 limit of 2200'F, therefore, a reanalysis is not planned at this time.
COOPER NUCLEAR STATION P.O. Box 98 / Brownville, NE 68321-0098 Telephone: (402) 825-3811 / Fax: (402) 825-5211 www.nppd.com Kim
NLS2011095 Page 2 of 2 If you have any questions concerning this matter, please contact Kent Sutton, Nuclear Engineering Department Manager, at (402) 825-5105.
Sincerely, David W. Van Der Kamp Licensing Manager
/jo cc:
Regional Administrator USNRC - Region IV Cooper Project Manager USNRC - NRR Project Directorate IV-1 Senior Resident Inspector USNRC - CNS NPG Distribution CNS Records
ATTACHMENT 3 LIST OF REGULATORY COMMITMENTSJ 4 ATTACHMENT 3 LIST OF REGULATORY COMMITMENTS(D4 Correspondence Number: NLS2011095 The following table identifies those actions committed to by Nebraska Public Power District (NPPD) in this document. Any other actions discussed in the submittal represent intended or planned actions by NPPD. They are described for information only and are not regulatory commitments. Please notify the Licensing Manager at Cooper Nuclear Station of any questions regarding this document or any associated regulatory commitments.
COMMITMENT COMMITTED DATE COMMITMENT NUMBER OR OUTAGE None PROCEDURE 0.42 REVISION 27 PAGE 18 OF 25