SECY-19-0019, SRM-SECY-22-0019: Rulemaking Plan for the Revision of Embrittlement and Surveillance Requirements for High-Fluence Nuclear Power Plants in Long-Term Operation
| ML25196A437 | |
| Person / Time | |
|---|---|
| Issue date: | 07/15/2025 |
| From: | Carrie Safford NRC/SECY |
| To: | Mark King NRC/EDO |
| References | |
| SECY-19-0019 SRM-SECY-22-0019 | |
| Download: ML25196A437 (2) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 July 15, 2025 MEMORANDUM TO:
Michael F. King Acting Executive Director for Operations FROM:
Carrie M. Safford, Secretary
SUBJECT:
STAFF REQUIREMENTS - SECY-22-0019 - RULEMAKING PLAN FOR THE REVISION OF EMBRITTLEMENT AND SURVEILLANCE REQUIREMENTS FOR HIGH-FLUENCE NUCLEAR POWER PLANTS IN LONG-TERM OPERATION The Commission has approved the staffs recommendation (Alternative 2) to initiate a rulemaking to amend the reactor pressure vessel embrittlement and surveillance requirements in Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Domestic Licensing of Production and Utilization Facilities. This alternative would revise Appendix H, Reactor Vessel Material Surveillance Program Requirements, to Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Domestic Licensing of Production and Utilization Facilities to include additional surveillance testing requirements for long-term operation and revise the fluence function fit through appropriate updates to 10 CFR 50.61, Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events, and guidance, including Regulatory Guide 1.99, Rev. 2, Radiation Embrittlement of Reactor Vessel Materials.
To the extent practicable, the staff should ensure the proposed rule is performance-based and includes appropriate provisions to ensure surveillance data is available to cover a plants projected period of operation.
The staff should assess and consider as appropriate, stakeholder interest in a regulatory framework that also permits voluntary adoption of alternative vessel embrittlement approaches for operating and new reactors as part of this rulemaking effort. Other correlations to set safety margins may be more appropriate for new designs, and to the extent applicants elect to use more refined correlations where appropriate justification and data gathering support them, the regulatory framework should facilitate that.
To support effective embrittlement modeling and surveillance, the staff should develop options with input from stakeholders for revising the fluence fit function. The staff should ensure that these options do not unnecessarily limit licensees to a single calculation or model as part of a technology-inclusive and performance-based approach to regulation.
In addition to this rulemaking, staff should explore the potential for artificial intelligence to analyze existing data on embrittlement as a supplement to future coupon sampling and analysis.
CARRIE SAFFORD Digitally signed by CARRIE SAFFORD Date: 2025.07.15 15:33:19
-04'00'
Consistent with Executive Order (EO) 14300, Ordering the Reform of the Nuclear Regulatory Commission, and in accordance with NRCs principles of good regulation, the staff should work with the Office of the General Counsel to identify rulemaking efficiencies, where appropriate, and ensure that this rulemaking is coordinated with any efforts to revise NRCs regulations pursuant to Section 5 of EO 14300.
cc: Commissioner Caputo Commissioner Crowell Commissioner Marzano OGC CFO OCA OPA ODs, RAs, ACRS, ASLBP PDR