L-2014-359, 10 CFR 50.46 Acceptance Criteria for Emergency Core Cooling Systems in Light Water Nuclear Power Reactors, 30 Day Special Report

10 CFR 50.46 Acceptance Criteria for Emergency Core Cooling Systems in Light Water Nuclear Power Reactors, 30 Day Special Report

ML14351A073
Person / Time
Site:	Turkey Point
Issue date:	12/03/2014
From:	Kiley M Florida Power & Light Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
L-2014-359
Download: ML14351A073 (2)

Text

0 December 3, 2014 FPL. L-2014-359 10 CFR 50.46 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D. C. 20555-0001 Re: Turkey Point Units 3 and 4 Docket Nos. 50-250 and 50-251 10 CFR 50.46, "Acceptance Criteria for Emergency Core Cooling Systems in Light Water Nuclear Power Reactors" - 30 Day Special Report

References:

1. Florida Power & Light Company (FPL) letter, M. Kiley to U. S. Nuclear Regulatory Commission, "Turkey Point Unit 3, Docket No. 50-250, 10 CFR 50.46, 'Acceptance Criteria for Emergency Core Cooling Systems in Light Water Nuclear Power Reactors' - 30 Day Special Report," L-2014-077, March 24, 2014.

2. Florida Power & Light Company (FPL) letter, M. Kiley to U. S. Nuclear Regulatory Commission, "Turkey Point Unit 4, Docket No. 50-251, 10 CFR 50.46, 'Acceptance Criteria for Emergency Core Cooling Systems in Light Water Nuclear Power Reactors' - 30 Day Special Report," L-2014-302, October 15, 2014.

10 CFR 50.46(a)(3)(ii) requires that changes to the Large Break Loss of Coolant Accident (LBLOCA) Evaluation Model (EM) and Small Break LOCA (SBLOCA) EM peak clad temperature (PCT) exceeding 50°F have to be reported to the NRC within 30 days. This letter meets this requirement.

FPL letters L-2014-077 (Reference 1) and L-2014-302 (Reference 2) submitted the 30 Day Special Reports for Turkey Point Units 3 and 4, respectively. The 30 Day Special Reports documented a LBLOCA PCT of 2121OF with a cumulative change of 77 0 F. The LBLOCA PCT reported in the 30 day special reports removed the 120 F mixed core penalty no longer applicable for Unit 3 Cycle 27 and Unit 4 Cycle 28 and future cycles with only 15x1 5 Upgraded fuel assemblies.

By letter dated November 19, 2014, Westinghouse identified an error in the LBLOCA EM in the calculation of decay heat in the WCOBRA/TRAC code. Correction of the errors impacts the application of the sampled decay heat uncertainty, which may result in small changes to the decay heat power. These issues have been evaluated to estimate the impact on Automated Statistical Treatment of Uncertainty Method (ASTRUM) Best-Estimate (BE) LBLOCA analysis results. The correction of these errors resulted in an estimated impact of +3 OF on LBLOCA PCT for Turkey Point Units 3 and 4. Table 1 below provides a summary of the new LBLOCA PCT for Turkey Point Units 3 and 4. The revised LBLOCA PCT for Units 3 and 4 is 2124 OF with a cumulative change of 80°F due to the LBLOCA EM errors. The SBLOCA EM is not affected by the identified errors.

Florida Power & Light Company 9760 SW 344 St Homestead, FL 33035

L-2014-359 Page 2 of 2 Table I Turkey Point Units 3 and 4 LBLOCA Evaluation Model Error Peak Cladding Cumulative Temperature Change LBLOCA 10 CFR 50.46 30-day Special Reports (Refs.1 & 2) 2121 OF 77 OF 2014 ECCS Model Assessments 3 OF 3 OF Decay Group Uncertainty Factors Errors December 2014 30 Day Special Report 2124 OF 80 OF 10 CFR 50.46(a)(3)(ii) also requires that a schedule for reanalysis be provided or compliance with the requirements of the regulation be shown if the error is significant. For the Turkey Point Units continued compliance with 10 CFR 50.46 requirements is demonstrated by the new estimated LBLOCA PCT of 2124°F remaining below the limit of 2200 0 F.

Should there be any questions, please contact Robert Tomonto, Licensing Manager, at 305-246-7327.

Very truly yours, Michael Kiley Vice President Turkey Point Nuclear Plant cc: Regional Administrator, Region II, USNRC Senior Resident Inspector, USNRC, Turkey Point Plant