NLS2013006, Annual Report of Changes and Errors in Emergency Core Cooling System Evaluation Models for 2012

Annual Report of Changes and Errors in Emergency Core Cooling System Evaluation Models for 2012

ML13017A408
Person / Time
Site:	Cooper
Issue date:	01/14/2013
From:	Vanderkamp D Nebraska Public Power District (NPPD)
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
NLS2013006
Download: ML13017A408 (3)

Text

N Nebraska Public Power District Always there when you need us NLS2013006 50.46(a)(3 )(ii)

January 14, 2013 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555-0001

Subject:

Annual Report of Changes and Errors in Emergency Core Cooling System Evaluation Models for 2012 Cooper Nuclear Station, Docket No. 50-298, DPR-46

References:

1. Letter from David Van Der Kamp, Nebraska Public Power District, to U.S. Nuclear Regulatory Commission, dated August 18, 2008, "Failure to Include Error in Emergency Core Cooling System Evaluation Model in Annual Report for 2006"

2. Letter from David Van Der Kamp, Nebraska Public Power District, to U.S. Nuclear Regulatory Commission, dated September 21, 2011, "10 CFR 50.46(a)(3)(ii) Report"

Dear Sir or Madam:

The purpose of this letter is to submit the 2012 annual report of changes or errors in the Emergency Core Cooling System (ECCS) Evaluation Models pursuant to 10 CFR 50.46(a)(3)(ii) for Cooper Nuclear Station (CNS).

By reference letters 1 and 2, Nebraska Public Power District previously reported errors in the ECCS evaluation model for GEl4 fuel. These errors continue to apply to the ECCS evaluation methodology for 2012 and have a cumulative impact of 1307F on the Peak Cladding Temperature (PCT). In November 2012, CNS received General Electric Hitachi (GEH) 10 CFR 50.46 Notification Letter 2012-01 which reported an additional change to the ECCS acceptable evaluation model for GE14 fuel that results in a 15'F increase in the PCT. This 10 CFR 50.46 Notification estimated the magnitude of the change in PCT due to the change in fuel properties from GESTR to PRIME. PRIME fuel properties will be used as part of the evaluation model at the next ECCS-Loss of Coolant Accident reanalysis. Collectively, the errors/changes reported by GEH result in a PCT of 2185°F for GE14 fuel.

During the fall 2012 refueling outage, CNS installed GNF2 fuel in the core. The licensing basis PCT for the GNF2 fuel was 2140'F. However, GEH 10 CFR 50.46 Notification Letter 2012-01 reported to CNS in November 2012 (discussed above) also affected GNF2 fuel, resulting in a 307F increase in the PCT. This change increases the PCT from 21407F to 2170'F for GNF2 fuel.

COOPER NUCLEAR STATION P.O. Box 98 / Brownville, NE 68321-0098 Telephone: (402) 825-3811 / Fax: (402) 825-5211 w.wwnppd.com

NLS2013006 Page 2 of 2 All changes/errors are itemized in the attachment to this letter. CNS continues to comply with the PCT limit of 2200'F specified in 10 CFR 50.46(b)(1) for both GEl 4 and GNF2 fuel types.

This letter makes no regulatory commitments.

If you have any questions regarding this report, please contact Lorne Covington, Reactor Engineering Supervisor, at (402) 825-5052.

Sincerely, David W. Van Der Kamp Licensing Manager

/lb Attachment - Changes/Errors in Emergency Core Cooling System Evaluation Models for 2012 cc: Regional Administrator w/attachment USNRC - Region IV Cooper Project Manager w/attachment USNRC - NRR Project Directorate IV-1 Senior Resident Inspector w/attachment USNRC - CNS NPG Distribution w/attachment CNS Records w/attachment

NLS2013006 Attachment Page 1 of I Changes/Errors in Emergency Core Cooling System Evaluation Models for 2012 Nebraska Public Power District - Cooper Nuclear Station GE 14 Fuel GE Hitachi Date Subject PCT Impact 10 CFR 50.46 (OF)

Notification Letter 2006-01 7/28/06 Impact of Top Peaked Power 0°F Shape for Small Break Loss of Coolant Accident Analysis 2011-02 9/2/11 Impact of Database Error for Heat 35 0 F Deposition on the Peak Cladding Temperature (PCT) for I Ox1 0 Fuel Bundles 2011-03 9/2/11 Impact of Updated Formulation 95 0 F for Gamma Heat Deposition to Channel Wall for 9x9 and 1Ox 10 Fuel Bundles 2012-01 11/29/12 PRIME Fuel Properties 150 F Implementation for Fuel Rod Thermal/Mechanical Performance, Replacing GESTR Fuel Properties Total = 145°F PCT at beginning of 2012 = 2170'F PCT at end of 2012 = 2185°F GNF2 Fuel GE Hitachi Date Subject PCT Impact 10 CFR 50.46 Notification (OF)

Letter 2012-01 11/29/12 PRIME Fuel Properties 30°F Implementation for Fuel Rod Thermal/Mechanical Performance, Replacing GESTR Fuel Properties Total = 30°F Initial PCT = 2140°F PCT at end of 2012 = 2170 °F