NLS2023005, Annual Report of Changes and Errors in Emergency Core Cooling System Evaluation Models for 2022

Annual Report of Changes and Errors in Emergency Core Cooling System Evaluation Models for 2022

ML23019A336
Person / Time
Site:	Cooper
Issue date:	01/19/2023
From:	Dewhirst L Nebraska Public Power District (NPPD)
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
NLS2023005
Download: ML23019A336 (1)

Text

Nebraska Public Power District Al.ways there when you need us NLS2023005 50.46( a)(3 )(ii)

January 19, 2023 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 2022 Cooper Nuclear Station, Docket No. 50-298, DPR-46

Reference:

Letter from Linda Dewhirst, Nebraska Public Power District, to U.S. Nuclear Regulatory Commission, dated January 20, 2022, "Annual Report of Changes and Errors in Emergency Core Cooling System Evaluation Models for 2021"

Dear Sir or Madam:

The purpose of this letter is to submit the 2022 annual report of changes and errors in the Emergency Core Cooling System (ECCS) evaluation models pursuant to 10 CFR 50.46(a)(3)(ii) for Cooper Nuclear Station (CNS).

Per the reference letter, Nebraska Public Power District previously reported errors/changes in the ECCS evaluation models for GNF2 fuel, these errors continued to apply to the ECCS evaluation methodologies for 2022. There were two zero-degree errors for the GNF2 fuel type reported in 2022 applicable to the licensing basis peak clad temperature (PCT). CNS continues to comply with the PCT limit of 2200°F specified in 10 CFR 50.46(b)(l). to this letter itemizes the changes/errors in the ECCS evaluation models that remained applicable in 2022 and Attachment 2 provides data that demonstrates compliance with the ECCS performance requirements of 10 CFR 50.46.

This letter makes no regulatory commitments.

If you have any questions regarding this report, please contact Cody Stuchal, Reactor & Fuels Engin ef, at (402) 825-5658.

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

NLS2023005 Page 2 of2 Attachments: 1) Changes/Errors in Emergency Core Cooling System Evaluation Models Applicable in 2022

2) 10 CFR 50.46 Criteria in Emergency Core Cooling System Evaluation Models for 2022 cc: Regional Administrator w/attachments USNRC - Region IV Cooper Project Manager w/attachments USNRC - NRR Plant Licensing Branch IV Senior Resident Inspector w/attachments USNRC-CNS NPG Distribution w/attachments CNS Records w/attachments

NLS2023005 Page 1 of 1 Changes/Errors in Emergency Core Cooling System Evaluation Models Applicable in 2022 GNF2 Fuel GE Hitachi Date Subject PCT Impact 10 CFR 50.46 Notification Letter 2017-01 6/12/17 GNF2 Lower Tie -20°F Plate Leakage 2017-02 8/2/17 Fuel Rod Plenum ooF Temperature Update 2019-05 11/1/19 SAFER Lower Limit ooF on Differential Pressure for Bypass Leakage 2020-01 4/14/20 PRIME Code Errors ooF for Evaluation Model Fuel Rod Condition Inputs 2021-01 2/18/21 Fuel Pellet to Plenum ooF Spring Conductance Input to ECCS LOCA Calculations 2021-02 2/18/21 Inner Cladding ooF Surface Roughness Input to Gap Conductance Model Total = -20°F

NLS2023005 Page 1 of 1 10 CFR 50.46 Criteria in Emergency Core Cooling System Evaluation Models for 2022 Fuel Type Licensing Basis PCT Local Oxidation Core-Wide Metal-Water Reaction GNF2 2130°F <6.00% <0.10%