ML14055A399

Best Estimate Large Break Loss of Coolant Accident (Be LBLOCA)10 CFR 50.46 30-Day Report

ML14055A399
Person / Time
Site:	Seabrook
Issue date:	02/18/2014
From:	Ossing M NextEra Energy Seabrook
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
SBK-L- 14040
Download: ML14055A399 (4)

Text

NEXTera ENERG7YýQ/ ýSEABROOK February 18, 2014 Docket No. 50-443 SBK-L- 14040 United States Nuclear Regulatory Commission Attention: Document Control Desk Washington. D.C. 20555-0001 Seabrook Station Best Estimate Large Break Loss of Coolant Accident (BE LBLOCA) 10 CFR 50.46 30-Day Report

Reference:

Letter from M. H. Ossing (NextEra) to U.S. Nuclear Regulatory Commission (SBK-L-13166, Docket No. 50-443), "Seabrook Station, Impact of Revised Heat Transfer Multiplier Distributions and Other Errors On Current Seabrook BE LBLOCA Peak Clad Temperature (PCT) 10 CFR 50.46 30-day Report," August 28, 2013.

In accordance with the requirements of 10 CFR 50.46(a)(3)(ii), NextEra Energy Seabrook, LLC (NextEra) submitted the referenced letter to report the impact of errors on the Seabrook Best Estimate Large Break Loss of Coolant Accident (BE LBLOCA) The reported LBLOCA PCT and cumulative change were 1919 OF and 135 °F, respectively.

10 CFR 50.46(a)(3)(ii) requires that changes to the LBLOCA Evaluation Model (EM) and SBLOCA EM PCT resulting in cumulative changes and errors such that the sum of the absolute magnitudes of the respective temperature changes is greater than 50 'F be reported to the NRC within 30 days. This 30-day report documents an error made in the Seabrook BE LBLOCA analysis.

The enclosure provides the new LBLOCA PCT rackup for Seabrook Station that accounts for the error. The new LBLOCA predicted values for the PCT and the cumulative change are 1939 OF and 155 OF, respectively.

NextEra Energy Seabrook, LLC.

626 Lafayette Rd, Seabrook, NH 03874 Acvl,

U. S. Nuclear Regulatory Commissioln SBK-L-14040 / Page 2 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. Continued compliance with 10 CFR 50.46 requirements is demonstrated by the total estimated new PCT value of 1939 °F remaining well below the limit of 2200 OF.

Should you have any questions regarding this report, please contact me at (603) 773-7512.

Sincerely, NextEra Energy Seabrook, LLC Mictiael W~.Ossing/

Licensing Managet cc: NRC Region I Administrator J. Lamb, NRC Project Manager, Project Directorate 1-2 NRC Senior Resident Inspector

ENCLOSURE TO SBK-L-14040 Seabrook 10CFR 50.46 BELOCA PCT Peak Clad Cumulative LBLOCA Temperature Change 2013 10 CFR 50.46 30-Day Report (1) 1919 OF 135 OF Chan.qes / Errors

- Error in Burst Strain Application (2) +20 OF 20 -F 10 CFR 50.46 30-Day Report 1939 OF 155 OF References

1. Letter from M. H, Ossing (NextEra) to U.S. Nuclear Regulatory Commission (SBK-L-13166, Docket No. 50-443), "Seabrook Station, Impact of Revised Heat Transfer Multiplier Distributions and Other Errors On Current Seabrook BE LBLOCA Peak Clad Temperature (PCT) 10 CFR 50.46 30-day Report," August 28, 2013. -

2. Westinghouse letter, E. M. Malek to R. Rodriguez, "NextEra Energy Seabrook Station 10 CFR 50.46 Report for the HOTSPOT Burst Strain Error Correction," NF-NA-14-15, January 31, 2014.