March 2026 has brought the National Environmental Protection Act (NEPA) to the forefront of many disputes and political issues across the U.S. Notable NEPA challenges include challenges to the Department of the Interior’s (DOI) expedited approval of coal mine expansions following an executive order declaring an “energy emergency” as well as challenges to U.S. Immigration and Customs Enforcement’s (ICE) development of detention centers without completing Environmental Impact Statements (EIS). Additionally, the U.S Supreme Court is gearing up to take another look at NEPA, which could have profound impacts on agency decision-making and permitting processes.

Montana Coal Mine

Environmental groups are seeking to vacate the federal government’s approval of a plan to expand operations at the Bull Mountains coal mine in Montana, which has been the source of litigation for years. The suit filed on March 3, 2026, alleges that the U.S. Office of Surface Mining Reclamation and Enforcement (OSM) and DOI flouted environmental concerns and theirown regulations when they approved the mining modification plan in June, 2025 withoutpreparing a draft environmental impact statement (EIS), failing to accept public input beyond comments submitted at the scoping stage, or generally considering public comments.

Last June, OSM announced that it had completed its EIS for the mine and issued a record of decision under its newly established alternative arrangements for compliance with NEPA. The alternative arrangements were adopted last year pursuant to President Donald Trump’s executive order, which declared a national energy emergency and directed agencies to expedite fossil-fuel-related projects. DOI and OSM have taken the position that the mine’s EIS is sufficient and meets the level of analysis required in an EIS after the U.S. Supreme Court’s ruling last year in Seven County Infrastructure Coalition v. Eagle County, Colorado, which found that up and downstream environmental effects of a project, such as greenhouse gas production from fossil fuel extraction, do not need to be considered in an EIS.

This lawsuit will likely test the strength of DOI and OSM’s new NEPA regulations and the bounds of what constitutes an emergency, although the ongoing issues with energy supply,due to the closing of the Strait of Hormuz, may give additional weight to the agencies’ concerns.

ICE Detention Facilities

States and local municipalities have been fighting back against ICE and the U.S. Department of Homeland Security’s (DHS) recent shopping spree, in which they have bought up warehouses and land to build detention centers.

In January 2026, ICE and DHS acquired a $102.2 million warehouse in Williamsport, Maryland, with plans to convert the property into a detention center. The purchase prompted the Maryland Attorney General’s Office to file a lawsuit in February. The suit alleges that converting the 825,620-square-foot warehouse into a detention center required a thorough NEPA analysis as the project would increase traffic, lack sufficient sewage infrastructure, and impact state waterways and federally protected species. DHS and ICE refute these claims and contend that the project falls into a set of categorical exclusions, and no analysis is required.

On March 12, U.S. District Judge Brendan A. Hurson issued a temporary restraining order blocking DHS and ICE from proceeding with work to convert the warehouse. Judge Hurson found that the agencies had failed to properly examine the renovation’s potential environmental impact, as neither an EIS nor an environmental assessment (EA) was completed.The parties are now scheduled for oral arguments on the injunction on April 15.

This case mirrors the allegations that environmental groups levied against the planned construction of the South Florida Detention Center, dubbed “Alligator Alcatraz” by Florida Attorney General James Uthmeier, alleging in a complaint last June that the state, DHS, and ICE failed to properly vet the environmental impacts of constructing the facility near protected wetlands.

There, the Florida district court also issued a temporary restraining order. It later issued a preliminary injunction after finding that the environmental groups were likely to prevail on their claims. On appeal, the Eleventh Circuit reversed the preliminary injunction, finding neither the construction nor the use of the facility constituted a “major federal action” warranting review under NEPA in the absence of federal funding or federal control. These parties are also teed up for oral arguments in April on the injunction.

Similar suits have been filed in New Jersey and Michigan concerning ICE and DHS’sefforts to convert vacant warehouses into detention facilities. All of these cases, playing out at the same time, will set the stage for similar suits challenging ICE’s and DHS’s compliance with NEPA in regard to detention facilities across the country.

SCOTUS’s New NEPA Case

On March 9, 2026, the U.S. Supreme Court granted certiorari in Department of the Air Force v. Prutehi Guahan, a case that asks whether the Air Force’s submission of a Resource Conservation and Recovery Act (RCRA) permit renewal application is a reviewable final agency action and triggers NEPA review. The case involves the Air Force’s practice of open burning and open detonation of hazardous waste munitions at Tarague Beach, Guam. For decades, the Guam Environmental Protection Agency approved RCRA permits for this practice, but in 2021, the agency delayed the Air Force’s renewal application based on public comments. In 2022, an environmental group filed suit, alleging that the Air Force violated NEPA by failing to conduct a NEPA review in seeking renewal of its RCRA permit.

This case raises two significant questions at the crossroads of RCRA, NEPA, and administrative law: (1) whether a federal agency’s submission of a permit renewal application under a permitting program constitutes a reviewable final agency action; and (2) whether NEPA review must precede that submission.

The Air Force and its backers argue that because RCRA already establishes a detailed regulatory framework for hazardous waste treatment, storage, and disposal, including technical permitting requirements, agency oversight, and public participation. Thus, RCRA’s frameworkgoverns and precludes the application of NEPA’s more general environmental-review requirements, and further, a permit application is not a reviewable final agency action because it only sets the stage for a subsequent decision and does not have legal consequences. They additionally argue that requiring such extensive review of a permit renewal for longstanding agency operations has the potential to envelop almost any decision made by an agency, openingthe door to judicial review of a wide array of decision-making steps that were previously considered intermediary.

Opponents contend that the act of applying for renewal reflects a sufficiently definite commitment to a particular disposal method and location to trigger NEPA and to qualify as final agency action. Thus, the Air Force had effectively committed to continuing a course of action with environmental consequences by submitting a renewal application.

This is shaped up to be the Court’s big return to NEPA after its decision in Seven County Infrastructure Coalition v. Eagle County, where it emphasized NEPA’s procedural character and indicated that it was skeptical of interpretations that expand NEPA beyond its statutory function (see CMBG3’s article on the decision). This new case gives the Court an opportunity to revisit those ideas in a different setting, not by focusing on the adequacy of an environmental reviewitself, but by addressing when NEPA is triggered in the context of an environmental permitting program. Thus, this case could become an important statement on the limits of NEPA as a tool for challenging agency action at the front end of the regulatory process.

Implications

The implications of these cases extend beyond federal facilities and hazardous waste operations. Many regulated entities operate under specialized environmental permitting programs that already require substantial technical submissions, agency reviews, and public participation. Against that backdrop, the Courts’ treatment of finality, statutory overlap, and the adequacy of agency rationale could shape a broader range of disputes concerning when environmental review must occur, whether an existing permitting process is sufficient to address concerns, and at what point litigation risk arises. The decisions in these cases are likely to affect not only federal agencies but also the broad array of regulated entities whose operations depend on the sequencing, durability, and defensibility of permit approvals and renewals.

For assistance with navigating this emerging NEPA landscape or other environmental matters, please contact CMBG3 Law and our environmental team. Our team is ready to provide guidance on regulatory issues, policy changes, and compliance concerns.