L-2024-127, Supplement to Letter L-2024-108, Response to Request for Additional Information (RAI) Regarding One Time Extension to Technical Specification 3.8.1.1.a, Allowed Outage Time with One Independent

Supplement to Letter L-2024-108, Response to Request for Additional Information (RAI) Regarding One Time Extension to Technical Specification 3.8.1.1.a, Allowed Outage Time with One Independent

ML24219A036
Person / Time
Site:	Seabrook
Issue date:	08/05/2024
From:	Rasmus P NextEra Energy Seabrook
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
L-2024-127
Download: ML24219A036 (1)

Text

August 05, 2024 L-2024-127 10 CFR 50.90 NextEra Energy Seabrook, LLC P.O. Box 300, Lafayette Road, Seabrook, NH 03874 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington DC 20555-0001 RE:

Seabrook Station Docket No. 50-443 Renewed Facility Operating License No. NPF-86 Supplement to NextEra Energy Seabrook, LLC, letter L-2024-108, Response to Request for Additional Information (RAI) Regarding One Time Extension to Technical Specification 3.8.1.1.a, Allowed Outage Time with One Independent Circuit Between the Offsite Transmission Network and the Onsite Class 1E Distribution System Out-of-Service, March 4, 2024 (ADAMS Accession No. ML24198A026)

References:

1.

NextEra Energy Seabrook, LLC, Letter L-2024-061, License Amendment Request a One Time Extension to Technical Specification 3.8.1.1.a, Allowed Outage Time with One Independent Circuit Between the Offsite Transmission Network and the Onsite Class 1E Distribution System Out-of-Service, May 24, 2024 (ADAMS Accession No. ML24131A152)

2.

NRC Electronic Memorandum dated June 25, 2024, Request for Additional Information (RAI)

- Seabrook LAR offsite power, Regarding the One Time License Amendment Request to Revise Technical Specification 3.8.1, Offsite Sources - Operating, Seabrook Station, Unit 1, Docket No. 50-443

3.

NextEra Energy Seabrook, LLC, letter L-2024-108, Response to Request for Additional Information (RAI) Regarding One Time Extension to Technical Specification 3.8.1.1.a, Allowed Outage Time with One Independent Circuit Between the Offsite Transmission Network and the Onsite Class 1E Distribution System Out-of-Service, March 4, 2024 (ADAMS Accession No. ML24198A026)

In Reference 1, NextEra Energy Seabrook, LLC (NextEra) requested, pursuant to 10 CFR 50.90, a one-time License Amendment to Renewed Facility Operating License NFP-86 for Seabrook Nuclear Plant Unit 1 (Seabrook). The proposed change to Technical Specification (TS) 3.8.1.1.a, A.C. Sources

- Operating, would provide a one-time allowance to change plant modes from Cold Shutdown (MODE

5) to Startup (MODE 2) while one independent circuit between the offsite transmission network and the onsite Class 1E Distribution System is out of service. NextEra is requested an additional 384 hours0.00444 days <br />0.107 hours <br />6.349206e-4 weeks <br />1.46112e-4 months <br /> to the 3.8.1.1.a 72-hour completion time for a total of 456 hours0.00528 days <br />0.127 hours <br />7.539683e-4 weeks <br />1.73508e-4 months <br />.

In Reference 2, the NRC staff forwarded Requests for Additional Information (RAIs) deemed necessary to complete its review. A clarification call was held with the staff, on June 25, 2024, and in Reference 3, NextEra provided a response to the RAIs.

Subsequent to the RAI response submittal, and as a result of RAI discussions held with the NRC staff, NextEra hereby requests a modified TS 3.8.1.1.a Allowed Outage Time (AOT) from 456 hours0.00528 days <br />0.127 hours <br />7.539683e-4 weeks <br />1.73508e-4 months <br /> to 240 hours0.00278 days <br />0.0667 hours <br />3.968254e-4 weeks <br />9.132e-5 months <br />.

This submittal also corrects a compensatory action described in Reference 3, RAI-3 response, for severe weather. NextEra stated that, in advance of a 5-day prediction for severe weather, MODE

Seabrook Station L-2024-127 Docket Nos. 50-443 Page 2 of 2 changes from MODE 5 to MODE 4 would be prohibited. The correction is, in advance of a 2-day prediction for severe weather, MODE changes from MODE 5 to MODE 4 would be prohibited.

The Enclosure to this submittal provides a revised TS 3.8.1.1.a markup, indicating the requested AOT extension is 240 hours0.00278 days <br />0.0667 hours <br />3.968254e-4 weeks <br />9.132e-5 months <br />. The revised markup supersedes and replaces the corresponding TS 3.8.1.1.a markup page provided in Reference 1.

The information included in this Reference 1 supplement provides additional information that clarifies the application, does not expand the scope of the application as originally noted, and should not change the NRC staffs originally proposed no significant hazards consideration determination as published by the Federal Registered.

This letter contains no new or revised regulatory commitments.

Should you have any questions regarding this submission, please contact Mr. Kenneth Mack, Senior Manager, Licensing and Regulatory Compliance, at 561-904-3635.

I declare under penalty of perjury that the foregoing is true and correct.

Executed on the 5th day of August 2024.

Sincerely, Paul Rasmus General Manager, Regulatory Affairs Enclosure cc:

USNRC Region I Administrator USNRC Project Manager USNRC Senior Resident Inspector Director Homeland Security and Emergency Management New Hampshire Department of Safety Division of Homeland Security and Emergency Management Bureau of Emergency Management 33 Hazen Drive Concord, NH 03305 Katharine Cederberg, Lead Nuclear Planner The Commonwealth of Massachusetts Emergency Management Agency 400 Worcester Road Framingham, MA 01702-5399 for

Seabrook Station L-2024-127 Docket Nos. 50-443 ENCLOSURE PROPOSED TECHNICAL SPECIFICATION PAGES (MARKUP)