GO2-21-041, Report of Changes or Errors in Emergency Core Cooling System Loss of Coolant Accident Analysis Models Pursuant to 10 CFR 50.46

Report of Changes or Errors in Emergency Core Cooling System Loss of Coolant Accident Analysis Models Pursuant to 10 CFR 50.46

ML21074A336
Person / Time
Site:	Columbia
Issue date:	03/15/2021
From:	Dittmer J Energy Northwest
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
GO2-21-041
Download: ML21074A336 (2)

Text

ENERGY J. Kent Dittmer Columbia Generating Station NORTHWEST P.O. Box 968, PE01 Richland, WA 99352-0968 Ph. 509-377-4248 l F. 509-377-2354 jkdittmer@energy-northwest.com March 15, 2021 GO2-21-041 10 CFR 50.46(a)(3)(ii)

U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001

Subject:

COLUMBIA GENERATING STATION, DOCKET NO. 50-397 REPORT OF CHANGES OR ERRORS IN EMERGENCY CORE COOLING SYSTEM LOSS OF COOLANT ACCIDENT ANALYSIS MODELS PURSUANT TO 10 CFR 50.46

Dear Sir or Madam:

This report is provided in accordance with 10 CFR 50.46(a)(3)(ii), which requires, in part, annual reporting of changes to, or errors in, evaluation models used for calculating Emergency Core Cooling System (ECCS) performance, and an estimate of their effect on the limiting ECCS analysis.

The attached report provides the details related to changes affecting the analysis of record for this reporting period. The licensing basis Peak Clad Temperature for all fuel types in the core remains within the acceptance criteria set forth in 10 C FR 50.46 (i.e., s 2200 °F).

There are no commitments being made to the Nuclear Regulatory Commission herein. If you have any questions, or require additional information, please contact Ms. D.M.

Wolfgramm, Manager, Regulatory Affairs, at (509) 377-4792.

Executed on this ___ 15 day of March

_________, 2021.

Respectfully, I A DocuSigned by:

L:~o!:~LE!ttY J. Kent Dittmer Vice President, Engineering

Attachment:

Loss of Coolant Accident Margin Summary Sheet Annual Report for 2020 cc: NRC Region IV Administrator NRC NRR Project Manager NRC Senior Resident Inspector CD Sonoda BPA

GO2-21-041 Attachment Page 1 of 1 LOCA Margin Summary Sheet Annual Report (Per NFM-4-1 Table 7-b)

Plant Name: Columbia Generating Station Utility Name: Energy Northwest Evaluation Model: (Description or Name) GNF-2: SAFER/PRIME-LOCA Models Net PCT Absolute Effect PCT Effect GNF2 Fuel - Prior 10 CFR 50.46 Changes or Error Corrections - Prior year (2020)

GEH - NL 2020-01 PRIME coding errors ~PCT= 0 °F 0 °F GEH - NL 2020-02 Safer04A E4 Revision ~PCT= 0 °F 0 °F GNF2 Fuel - Prior 10 CFR 50.46 Changes or Error Corrections - This year (2021)

GEH - NL 2021-01 Error in Fuel Pellet to ~PCT= 0 °F 0 °F Plenum Spring Conductance GEH - NL 2021-02 Discrepancy in Inner ~PCT= 0 °F 0 °F Cladding Surface Roughness GNF2 Fuel -Absolute Sum of 10 CFR 50.46 ~PCT= 0 °F Changes The sum of the PCT (Peak Cladding Temperature) from the most recent analysis using an acceptable evaluation model and the estimates of PCT impact for changes and errors identified since this analysis is less than 2200 °F. PCT prior to this report was 1700 °F for GNF2 fuel.

The current PCT for this report is unchanged for GNF2 fuel.

References:

1. NE-02-03-08 Revision 8, "10CFR50.46 Cumulative PCT Changes in ECCS LOCA Models"

2. AR 00414172, Provide Licensing information per 10 CFR 50.46(a)(3)(ii)

3. NFM 1 Revision 3, "Tracking Changes in ECCS LOCA Analysis"