NRC Continues Overhauling New Reactor Regulations

The Nuclear Regulatory Commission (“NRC”) is continuing the regulatory reform prompted by Executive Order 14300, this time with a broad collection of proposed changes to its reactor regulations. On September 11, 2026, the NRC released its proposed rule, “Regulatory Enhancements for Reactor Licensing, Decommissioning, and Operational Oversight.” This latest rulemaking builds upon new reactor licensing frameworks and other rulemakings over the past year aimed at enhancing licensing efficiency.

The proposal would amend 10 CFR Parts 20, 21, 50, 52, 53, 55, 70, 72, and 75, touching requirements across reactor licensing, construction, operation, and decommissioning. Most of the proposed changes are relatively technical and incremental. They include eliminating expiration dates for future standard design approvals (“SDAs”), providing additional flexibility in environmental reviews for early site permits, revising backfitting requirements, updating operator licensing requirements, and eliminating or modifying a number of reporting and administrative requirements.

Although no single change fundamentally alters the reactor regulatory framework, the proposal is notable as another piece of the NRC’s much broader regulatory reform effort. It also includes a number of changes that could simplify particular licensing and compliance processes for reactor applicants and licensees.

The NRC estimates that the proposed changes would result in approximately $305 million to $398 million in net averted industry costs over 30 years.

Background on the Rule

The NRC’s proposed rule further implements Executive Order 14300 through targeted amendments across its reactor regulatory framework, including 10 CFR Parts 20, 21, 50, 52, 53, 55, 70, 72, and 75. The changes touch nearly every stage of the reactor lifecycle – from licensing and construction through operation and decommissioning. Across these areas, the proposal seeks to reduce unnecessary regulatory burden, provide greater flexibility, and focus NRC requirements and resources on matters most significant to safety and security.

The NRC estimates that the proposed changes would result in approximately $305 million to $398 million in net averted industry costs over 30 years, largely through eliminating or modifying unnecessary submissions and requirements and providing more flexible regulatory processes.

What the Proposed Rule Does

The proposed rule makes a number of targeted changes across nuclear reactor licensing and oversight requirements. Key provisions include:

• Financial Qualifications. Potentially one of the more consequential changes for new reactor development is the proposed revision to the NRC’s financial-qualification requirements. Parts 50 and 52 currently require certain applicants to demonstrate that they possess or have reasonable assurance of obtaining the funds necessary to construct and operate the facility. The proposal would instead apply the Part 53 standard that an applicant “appears to be financially qualified” – a less stringent financial-qualifications standard derived from the fuel-cycle framework and considered by the NRC during the last wave of combined license applications.
  
  The issue is particularly important for non-rate-regulated plants, which may have difficulty obtaining committed financing before receiving the NRC license that helps make the project financeable. The existing regulations can therefore create a chicken-and-egg problem: an applicant may need to demonstrate access to financing to obtain its license, while lenders and investors may be unwilling to commit that financing until the license has been issued.
  
  In 2014, the Commission directed the NRC staff to pursue a rulemaking to address this issue – and the proposed South Texas Project 3&4 facility was licensed under an exemption applying this new proposed standard. Among other things, the contemplated approach would have focused the licensing review on whether the applicant understood the estimated costs of constructing and operating the facility and allowed a license to be issued subject to conditions requiring the necessary construction funding to be in place before construction proceeded. The NRC ultimately discontinued that rulemaking and instead addressed financial qualifications through the Part 53 rulemaking. The current proposal would now extend the less prescriptive Part 53 standard to Parts 50 and 52, potentially addressing a financing obstacle that the NRC first identified during the previous round of new reactor licensing.

• Decommissioning Trust Funds. The proposal would also move qualifying operational withdrawals from decommissioning trust funds from an exemption process to a 60-working-day notice and negative-consent process.

• Standard Design Approvals. The proposal would remove the current 15-year expiration date for future SDAs and establish pathways for holders to make minor changes without prior approval and pursue material amendments through NRC review.

• Environmental Review Flexibility for Early Site Permits. The NRC would no longer require an environmental impact statement in every early site permit proceeding. Instead, it could use an EIS, environmental assessment, or categorical exclusion, as appropriate, based on reasonably foreseeable environmental effects.

• Backfitting and Issue Finality. The rule would eliminate the compliance-backfit exception, clarify that backfitting applies when a change “would be required by” a new or amended requirement rather than when it merely “may result from” one, and allow the NRC to relax requirements when doing so reduces unnecessary burden while maintaining reasonable assurance of adequate protection.

• Decommissioning Licensing. A new § 52.111 would allow Part 52 licensees to release portions of a site before license termination. The rule would also permit an upfront License Termination Plan prior to or within two years after permanent cessation, eliminate a separate PSDAR submission for that path, and harmonize certain decommissioning requirements across Parts 50, 52, and 53.

• Risk-Informed Seismic Design. Appendix S to Part 50 would allow multiple design-basis ground motions based on the risk significance and safety functions of structures, systems, and components instead of a single SSE-based framework.

• Probabilistic Risk Assessment. The proposal would extend § 50.69 to LWR construction-permit holders under Part 50, LWR design-certification applicants, and LWR combined-license and manufacturing-license holders under Part 52, permitting risk-informed categorization and treatment of structures, systems, and components earlier in design and licensing.

• Nonemergency Event Reporting. The proposal would eliminate several routine four-hour and eight-hour notifications while preserving reports for safety-significant events and allowing alternative transmission methods, including approved electronic channels.

• Operator Licensing. New Part 55 Subpart I would create an optional generally licensed reactor operator framework for self-reliant-mitigation facilities. The proposal would also eliminate the six-year renewal cycle for operator licenses, expand medical certifications to licensed medical examiners rather than physicians alone, and permit facility licensees to proctor and grade operating tests under NRC oversight.

• Administrative Streamlining. The proposal would eliminate or relax a number of periodic submissions across Parts 50, 52, 53, 70, and 72, consolidate defect-reporting requirements into Part 21, remove redundant TMI-era provisions, and modernize notification methods. Licensees would continue to maintain underlying records available through inspections or requests for additional information.

Where These Changes Fit in With Recent Nuclear Rulemakings

This rulemaking is one of many and cannot be read in isolation. Since Executive Order 14300 was signed on May 23, 2025, the NRC has initiated 23 rulemakings – a remarkable pace. We’ve written about many: in roughly 16 months, the agency has finalized the Part 53 advanced reactor licensing framework; proposed dedicated microreactor regulations under Part 57; proposed a pathway to leverage Department of Energy and Department of War authorizations; proposed a fusion regulatory framework; proposed to streamline contested hearings; and proposed two broad modernization rules covering materials licensing and reactor licensing practices. This rulemaking continues that broader effort, with changes to existing reactor requirements across licensing, operation, and decommissioning.

While other rulemakings such as the new Part 53 and proposed Part 57 have received significant attention, many near-term projects – including small modular reactors, large-reactor restarts, new AP1000 builds, and reactor uprates – will continue to be licensed under Parts 50 and 52. The changes in this proposal therefore apply directly to many of the projects now under development, as well as the existing fleet. They include changes to reporting obligations, backfitting requirements, financial qualifications and decommissioning trust funds, standard design approvals, and operator licensing.

This proposal also overlaps with other rulemakings underway as part of the NRC’s broader reform effort. It cross-references both the Modernizing Materials Licensing proposed rule and the Modernizing Reactor Licensing, Safety Oversight, and Siting Practices proposed rule for conforming changes, and several definitions and requirements depend on those parallel rulemakings becoming effective.

Implications for NRC Licensees and Applicants

Many of the proposed changes are incremental, and their practical impact will vary by applicant, licensee, and licensing pathway. Several, however, could have a more meaningful effect in particular circumstances.

• Financial qualifications could matter for new reactor financing. As discussed above, extending the Part 53 financial-qualifications standard to Parts 50 and 52 would revisit an issue that arose during the last round of new reactor licensing. For non-rate-regulated developers in particular, the existing requirements can create a chicken-and-egg problem where financing may be difficult to secure before a license is issued, but financial qualifications must be demonstrated to obtain the license. The proposed change could provide greater flexibility for projects that intend to secure construction financing later in the development process.

• Standard design approvals would become more durable. Removing the expiration date on SDAs would allow an approved design to remain available for reference in future applications without a recurring renewal deadline. The proposed change processes would also allow minor updates without prior NRC approval while preserving NRC review for more significant amendments. These changes could be particularly useful for vendors pursuing multiple deployments of a standardized design.

• Operating plants could see some reduction in recurring administrative requirements. The rule would remove or relax a number of periodic submission requirements, including reports involving quality-assurance plan changes, emergency plan changes, FSAR updates, finances, and certain nonemergency events. Licensees would generally continue to maintain the underlying information but would not be required to submit it automatically on a prescribed schedule.

• Decommissioning procedures would be simplified in several areas. Part 52 licensees would gain an express partial site-release provision, and licensees pursuing an upfront License Termination Plan could avoid a separate PSDAR submission. Qualifying access to decommissioning trust funds during operations would also move from an exemption process to a 60-working-day notice and negative-consent process.

• Backfitting requirements would be clarified. The proposed changes would narrow when a new or amended requirement constitutes a backfit and eliminate the compliance-backfit exception. For existing licensees and applicants with an established licensing basis, the changes could provide greater clarity about when the NRC must apply its backfit analysis before imposing new requirements.

• Operator licensing would become more flexible. The optional GLRO framework would provide a Part 55 pathway for facilities with self-reliant mitigation features that might otherwise require exemptions. Eliminating the six-year renewal cycle and making other changes to medical certifications and operating tests would also reduce some recurring licensing requirements.

Looking Ahead

This proposed rule is another part of the NRC’s broader effort to modernize its regulatory framework. While many of the changes are relatively technical and incremental, they reflect the agency’s ongoing review of existing requirements to identify opportunities to reduce unnecessary regulatory burden and provide greater flexibility while maintaining its safety and security standards.

The NRC will accept comments for 45 days after publication of the proposed rule in the Federal Register under Docket ID NRC-2025-1138. Potentially affected parties are encouraged to submit comments on the proposed changes and their potential impacts.