The US Department of Energy (DOE) has announced a “categorical exclusion for authorisation, siting, construction, operation, reauthorisation, and decommissioning of advanced nuclear reactors for inclusion in its National Environmental Policy Act (NEPA) implementing procedures”. DOE said it is including the categorical exclusion in the component of its NEPA implementing procedures that it maintains outside of the Code of Federal Regulations. “The new categorical exclusion is based on the experience of DOE and other Federal agencies, current technologies, regulatory requirements, and accepted industry practice.” The document, signed by Energy Secretary Chris Wright on 28 January, became effective on 2 February. DOE is soliciting comments on the changes until 4 March.
According to the announcement of the changes, published in the Federal Register, a categorical exclusion is a category of actions that DOE has determined “normally does not significantly affect the quality of the human environment and therefore does not require preparation of an environmental assessment or environmental impact statement”.
The exclusion effectively implements Executive Orders (EO) 14301 and 14299 issued by President Donald Trump in May 2025. Section 6 of EO 14301, Reforming Nuclear Reactor Testing at the Department of Energy on Streamlining Environmental Reviews, directs the Secretary of Energy to create ‘‘categorical exclusions as appropriate for reactors within certain parameters”. It states that “decades of research and engineering have produced prototypes of advanced nuclear technologies that incorporate passive safety mechanisms, improve the physical architecture of reactor designs, increase reactor operational flexibility and performance, and reduce risk in fuel disposal. Advanced reactors – including microreactors, small modular reactors, and Generation IV and Generation III+ reactors – have revolutionary potential.’’
EO 14299, Deploying Advanced Nuclear Reactor Technologies for National Security, directs the Secretaries of Defense and Energy to consult with the Chairman of the Council on Environmental Quality regarding ‘‘applying the Department of Defense’s and the Department of Energy’s established categorical exclusions under the National Environmental Policy Act (NEPA)… for the construction of advanced nuclear reactor technologies on certain Federal sites within the United States and for any other appropriate measures for the purposes of implementing this order’’ and ‘‘establishing new categorical exclusions for the same purposes”. It defines advanced reactors as including “nuclear energy systems like Generation III+ reactors, small modular reactors, microreactors, and stationary and mobile reactors that have the potential to deliver resilient, secure, and reliable power to critical defense facilities and other mission capability resources”.’
The Federal Register document says that: “In summary, advanced nuclear reactors have key attributes such as safety features, fuel type, and fission product inventory that limit adverse consequences from releases of radioactive or hazardous material from construction, operation, and decommissioning.”
It adds: “Although past advanced reactor projects have been for solely experimental, testing and demonstration purposes, the advanced fuel forms, inherently safe designs, and inventories of potential fission products associated with these reactors indicate that reactors in this category developed for additional purposes, such as power production and industrial applications, are also appropriate for this categorical exclusion.”
It notes: “Previously completed NEPA reviews have established that advanced reactors, including construction, operation, and decommissioning, characterized by technologies and materials (1) that have been verified to prevent adverse offsite consequences from release of radioactive or hazardous materials and (2) demonstrate that any hazardous waste, radioactive waste, or spent nuclear fuel generated by the project can be managed in accordance with applicable requirements do not significantly affect the quality of the human environment.”
DOE says it will still review whether a particular project meets the exclusion criteria and whether “extraordinary circumstances exist such that a normally excluded action may have a significant environmental effect”. However, it notes that “adverse consequences of the construction phase of advanced nuclear reactors are primarily related to the extent of land disturbance necessary to construct the facility footprint and are analogous to construction of non-nuclear industrial facilities”. DOE “will consider the construction impacts in accordance with applicable requirements (such as land use and zoning requirements) in the proposed project area”.
According to National Public Radio (NPR), “NEPA has long been a target of energy industries and Republican elected officials, including Trump. The exemption policy has been expected since Trump’s May orders, which also launched a DOE pilot programme to rapidly build the experimental reactors.” Section 5 of EO 14301 established a pilot programme for reactor construction and operation with the aim of having at least three reactors achieve criticality by 4 July 2026.
DOE said in a statement that it is “establishing the potential option to obtain a streamlined approach for advanced nuclear reactors as part of the environmental review performed under NEPA…. The analysis on each reactor being considered will be informed by previously completed environmental reviews for similar advanced nuclear technologies.”
However, the DOE announcement has drawn criticism from experts, including Daniel P Aldrich, Director of the Resilience Studies Program at Northeastern University. He wrote on social media: “Making America unsafe again: Trump created an exclusion for new experimental reactors from disclosing how their construction and operation might harm the environment, and from a written, public assessment of the possible consequences of a nuclear accident.”
Edwin Lyman, director of nuclear power safety at the Union of Concerned Scientists, warned that the lack of real-world experience with the reactors means they should be subject to more rigorous safety and environmental reviews before they’re built. “The fact is that any nuclear reactor, no matter how small, no matter how safe it looks on paper, is potentially subject to severe accidents,” he said. “I think the DOE’s attempts to cut corners on safety, security, and environmental protections are posing a grave risk to public health, safety, and our natural environment here in the United States.”
A week before, NPR senior editor and correspondent Geoff Brumfiel had obtained documents showing that DOE had shared early versions of the new rules with companies. These noted that “the reduction of unnecessary regulations will increase innovation in the industry without jeopardising safety,” and “the department anticipates publicly posting the directives later this year”. However, Brumfiel noted that the orders he saw weren’t labelled as drafts and had the word “approved” on their cover pages.
In a lengthy statement following the NPR report, Lyman wrote on the Union of Concerned Scientists website that “this deeply troubling development confirms my worst fears about the dire state of nuclear power safety and security oversight under the Trump administration”. He added: “Such a brazen rewriting of hundreds of crucial safeguards for the public underscores why preservation of the Nuclear Regulatory Commission (NRC) as an independent, transparent nuclear regulator is so critical. The Energy Department has not only taken a sledgehammer to the basic principles that underlie effective nuclear regulation, but it has also done so in the shadows, keeping the public in the dark.”
He noted: “These drastic changes may extend beyond the Reactor Pilot Program, which was created by President Trump last year to circumvent the more rigorous licensing rules employed by the NRC. While the DOE created a legally dubious framework to designate these reactors as ‘test’ reactors to bypass the NRC’s statutory authority, these dramatic alterations may further weaken standards used in the broader DOE authorisation process and propagate across the entire fleet of commercial nuclear facilities, severely degrading nuclear safety throughout the United States.”
Commenting on the new rules, which were shared with the companies but not disclosed to the public, Kathryn Huff, a professor of plasma and nuclear engineering at the University of Illinois Urbana-Champaign and former head of the DOE’s Office of Nuclear Energy, said the rules constitute “very clearly a loosening that I would have wanted to see exposed to public discussion”.
NPR said it had obtained copies of over a dozen of the new orders, none of which is publicly available. “The orders slash hundreds of pages of requirements for security at the reactors. They also loosen protections for groundwater and the environment and eliminate at least one key safety role. The new orders cut back on requirements for keeping records, and they raise the amount of radiation a worker can be exposed to before an official accident investigation is triggered.” According to NPR, more than 750 pages were cut from the earlier versions of the same orders, leaving only about one-third of the number of pages in the original documents.
“I would argue that the Department of Energy relaxing its nuclear safety and security standards in secret is not the best way to engender the kind of public trust that’s going to be needed for nuclear to succeed more broadly,” said Christopher Hanson, who chaired the Nuclear Regulatory Commission from 2021 to 2025, until he was fired by President Trump.
