L-2021-018, 10 CFR 50.46 Emergency Core Cooling System LBLOCA 30-Day Report

10 CFR 50.46 Emergency Core Cooling System LBLOCA 30-Day Report

ML21053A204
Person / Time
Site:	Turkey Point
Issue date:	02/16/2021
From:	Parks W Florida Power & Light Co
To:	Office of Nuclear Reactor Regulation
References
L-2021-018
Download: ML21053A204 (2)

Text

• FPL.

February 16, 2021 L-2021--018 10 CPR 50.46 U.S. Nuclear Rcgulat:ory Commission Attn: Document Control Desk Washington, DC 20555---0001--

Re: Florida Power & Light Company Turkey Point Units 3 and 4, Docket Nos. 50-250, 50-251 10 CFR 50.46 - Em~ Core Cooling System LBJ-4QCA 30--lliy Repott Pursuant to 10 CFR 50.46(a)(3)(t.i), this letter contains the 30--day report for the Florida Power & Llght's Turkey Point Nuclear Plant, Units 3 and 4, for the emergency core cooling system analysis performed by Westinghouse Electric Company, LLC, described in the attachment to this letter.

A legacy design input discrepancy was identified that affects the Small-Break (SB) and Large-Break (LB)

LOCA analyses. As the reported error is of a 0°F impact, the PCT continues to remain within the limits. However, as the cumulative PCT change already exceeds 50 °F for the LBLOCA a.nalysis, a 30 day 10CFRS0.46 report must be issued. An evaluation of the reported error has concluded that re-analysis is not required.

This letter contsins no new or revised regulatoi:y commitments.

Should you have any questions regarding this report, please contact Mr. Steve Ca.tron, Fleet .Llcensing Manager, at (561) 304-6206.

Very truly yours, 10iiJ~

William L Parks General Manager, Safety Assurance and Learning Florida Power & Light Company AttRchmeot (1) cc: USNRC Regional Administrator, Region II USNRC Project Manager, Turkey Point Nuclear Plant USNRC Senior Resident Inspector, Turkey Point Nuclear Plant Florida Power & Light Company 700 Universe Boulevard. Juno Beach, A. 33408

L-2021-018

• .._.. .tll 10 CFR 50.4{5 Attachment 1 Page 1 ofl Turkey Point Units 3 and 4 Large Break LOCA PCT 30-Day Report Evaluation Methodology:

Westinghouse, "Realistic Large-Break LOCA Evaluation Methodology Using the Automated Statistical

___ T~~!l! <?f U!_!~lY M ~ (~JRlJM),:'_ WCAP-16009-P.:-A, Revision 0, January 2005.- - -- - - - -

Evaluation Model PCT: 2152 °F (Reference 1)

NetPCT Absolute PCT Effect Effect Prior 10 CFR 50.46 Changes or Error Corrections - up to

-28 °P 80 °P year 2019 (Reference 2)

Prior 10 CFR 50.4§ Changes or Errors Corrections-year None 2020 and 2021 New 10 CFR 50.46 Changes or Errors Corrections -year 2021 Updated Pressuriz.er Surge Line & Accmnulator 0°F 0°F Line Data Sum of 10 CFR 50.46' Changes or Errors Corrections -28 °F 80 °P The sum ofthe PCTfrom the most recent analysis using an acceptable evaluation model and the estimates ofPCT 2124 °F < 2200 °F impact for changes and errors identified since this analysis Updated Pressurizer Surge Line & Accumulator Line Data Pressurizer surge and accumulator line inputs were discovered to be different than those used for the Best-Estimate large break LOCA (LBLOCA) analysis. The impact of updates to the pressurizer sarge line and accumulator line inputs to the LBLOCA analysis was qualitatively evaluated This change represents a Change in Plant Configuration or Set Points, distinguished from an evaluation model change in Section 4 of WCAP-13,451. The updates to the pressurizer surge line and accumulator line inputs have a negligiole effect on the Best-Estimate LBLOCA analysis results, leading to an estimated peak cladding impact of 0 op_

References:

1. Letter from M. Kiley to U.S. Nuclear Regulatory Commission, "Response to NRC Reactor Systems Branch Request for Additional Information Regarding Extended Power Uprate License Amendment Request No. 205 and Thermal Conductivity Degradation," L-2012-019, January 16, 2012.

2. Letter from W. Parks (FPL) to U.S. Nuclear Regulatory Commission, "10 CFR 50.46 Annual Reporting of Changes to, or Errors in Emergency Core Cooling System Models or Applications,"

L-2020-041, April 14, 2020.