ML26057A389
| ML26057A389 | |
| Person / Time | |
|---|---|
| Issue date: | 03/03/2026 |
| From: | Mclatchie H NRC/NRR/DANU/UARP |
| To: | Michael Wentzel NRC/NRR/DANU/UARP |
| McLatchie H | |
| References | |
| EPID L-2024-NFG-0012 | |
| Download: ML26057A389 (0) | |
Text
March 3, 2026 MEMORANDUM TO:
Michael Wentzel, Chief Advanced Reactor Policy Branch Division of Advanced Reactors and Non-power Production and Utilization Facilities Office of Nuclear Reactor Regulation FROM:
Hannah McLatchie, Project Manager /RA/
Advanced Reactor Policy Branch Division of Advanced Reactors and Non-power Production and Utilization Facilities Office of Nuclear Reactor Regulation
SUBJECT:
SUMMARY
OF JANUARY 29, 2026, OBSERVATION MEETING WITH SOUTHERN COMPANY TO DISCUSS THE TECHNOLOGY INCLUSIVE MANAGEMENT OF SAFETY CASE WHITE PAPER (EPID L-2024-NFG-0012)
Meeting Information:
Participant: Southern Company Services Public Meeting Notice Agencywide Documents Access and Management System (ADAMS)
Accession No.: ML26008A017 Industry Presentation Slides ADAMS Accession No.: ML26026A320 Meeting Attendees: See the enclosure for a list of meeting attendees.
CONTACT:
Hannah McLatchie, NRR/DANU/UARP 301-415-8507
Meeting Summary:
The U.S. Nuclear Regulatory Commission (NRC) staff conducted the meeting in accordance with NRC Management Directive 3.5, Attendance at NRC Staff-Sponsored Meetings (ADAMS Accession No. ML21180A271). On August 22, 2025, Southern Company Services submitted the Technology Inclusive Management of Safety Case (TIMaSC) White Paper (ML25239A009).
Prior to the meeting, NRC staff provided comments on the TIMaSC White Paper submittal (ML26007A324), and Southern Company developed slides to support the meeting (ML26026A320).
Southern Company began the meeting with an overview of the TIMaSC project and its place in a series of guidance being developed for advanced non-light water reactor applicants or licensees. The approach described in the TIMaSC white paper is technology-inclusive, risk-informed, and performance-based (RIPB) and is intended to be used by licensees implementing the Licensing Modernization Project (LMP) methodology, as described in NEI 18-04, Revision 1, Risk-Informed Performance-Based Technology-Inclusive Guidance for Non-Light Water Reactor Licensing Basis Development, and endorsed by the NRC in regulatory guide (RG) 1.233, Revision 0, Guidance for a Technology-Inclusive, Risk-Informed, and Performance-Based Methodology to Inform the Licensing Basis and Content of Applications for Licenses, Certifications, and Approvals for Non-Light Water Reactors. The white paper describes that the TIMaSC guidance development effort will take a comprehensive look at the licensing basis for an advanced reactor and provide clarity regarding how various processes, including deterministic requirements from legacy regulations, as well as recently endorsed RIPB approaches, interact with one another.
Southern Company provided a high-level timeline for the TIMaSC project. A draft guidance document has been developed by Southern Company to support tabletop exercises. The tabletop exercises are expected to be completed in April 2026, at which time the draft document will be refined based on lessons learned and submitted to the NRC for feedback. The TIMaSC project team expects to submit the final document to the NRC for endorsement in the summer of 2026.
Southern Company also identified specific groups of the NRC white paper comments on which to focus the January 29 discussion. Comments 2, 7, and 13 discuss the scope of the TIMaSC guidance document. Southern Company acknowledged the ongoing rulemakings and recognized that there may be future opportunities to widen the scope of the TIMaSC framework but plans to keep the focus on advanced reactors following the LMP methodology in NEI 18-04, Revision 1, and in accordance with Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Domestic Licensing of Production and Utilization Facilities, and 10 CFR Part 52, Licenses, Certifications, and Approvals for Nuclear Power Plants.
Comments 14, 15, 19, and 24 discuss the overall goals of the TIMaSC guidance. Southern Company confirmed that the intent for the TIMaSC guidance is to provide a framework that assists in managing changes and maintaining the licensing basis and to leverage existing programs and processes. The NRC staff agreed that it would be appropriate for the TIMaSC guidance to have no specific outputs and could instead be used to integrate activities and communications. The NRC staff discussed an example of using the TIMaSC framework as a link that would connect plant maintenance and probabilistic risk assessment management to ensure adequate communication, not to add additional requirements or programs. Similarly, the NRC staff suggested in comment 21 that the TIMaSC framework could avoid introducing new criteria to trigger NRC interactions, with which the TIMaSC project team agreed. The TIMaSC
project team explained that a key goal is to ensure management of the safety case is maintained consistent with how coordination across programs and operations under an LMP-based licensing basis would naturally occur by virtue of the integrated nature of establishing the licensing basis.
In comments 22 and 23, which reference the application of the Technology Inclusive Risk-Informed Change Evaluation (TIRICE) criteria to deterministic elements within the design basis, the NRC staff questioned if a revision to DG-1439 (RG 1.261), Guidance for Technology-Inclusive Risk-Informed Change Evaluation (endorsing NEI 22-05) should be considered. The TIMaSC project team stated that there are adequate evaluation criteria within NEI 22-05 that address deterministic elements, and that no changes are needed.
The NRC staff had no additional comments to raise on the TIMaSC white paper at the meeting.
Finally, the TIMaSC project team discussed the upcoming tabletop exercises and expressed their desire to include NRC observers to optimize the value. The TIMaSC project team asked the NRC staff for general availability information for staff to participate and indicated that they were receptive to topic suggestions. Advanced reactor developers will be involved in the tabletops and will run through scenarios with their detailed designs. The NRC staff agreed that observation of these tabletop exercises is valuable.
There were no questions or comments from members of the public or other stakeholders.
No regulatory decisions were made as a result of this meeting.
Enclosure:
List of Meeting Attendees
SUBJECT:
SUMMARY
OF JANUARY 29, 2026, OBSERVATION MEETING WITH SOUTHERN COMPANY TO DISCUSS THE TECHNOLOGY INCLUSIVE MANAGEMENT OF SAFETY CASE WHITE PAPER (EPID L-2024-NFG-0012)
DATED MARCH 3, 2026 DISTRIBUTION:
PUBLIC RidsNrrDanuUarp Resource MWentzel, NRR AGilbertson, NRR ADAMS Accession Number: ML26057A389 NRR-001 OFFICE NRR/DANU/UARP/PM NRR/DANU/UARP/BC NRR/DANU/UARP/PM NAME HMcLatchie MWentzel (JHarvey for)
HMcLatchie DATE 2/26/2026 3/3/2026 3/3/2026 OFFICIAL RECORD COPY
Enclosure LIST OF MEETING ATTENDEES FOR THE JANUARY 29, 2026, OBSERVATION MEETING WITH SOUTHERN COMPANY TO DISCUSS THE TIMaSC WHITE PAPER Name Organization Hannah McLatchie U.S. Nuclear Regulatory Commission (NRC)
Anders Gilbertson NRC William Reckley NRC Michael Wentzel NRC Brandon Chisholm Southern Company Steve Nesbit LMNT Consulting Michael Tschiltz Southern Company Consultant Jon Facemire Nuclear Energy Institute Amir Afzali Independent Contractor Marty Stutzke NRC Dave Grabaskas Argonne National Laboratory Thomas Byrne Excel Services Rob Burg EPM, Inc.
Caroline Tilton TerraPower Lauren Gibson X-Energy Ryan Donald Henderson Southern Company Matthew Hahn U.S. Department of Energy Spencer Toohill Public Ewa Muzikova Public Farshid Shahrokhi Framatome Christopher Paul Chwasz Idaho National Laboratory