In Seven County Infrastructure Coalition v. Eagle County, Colorado (2025) (May 29, 2025, No. 23-975) 605 U.S. ___, the U.S. Supreme Court held that NEPA affords substantial deference to an agency’s decisions about where to draw the line when considering indirect environmental effects. An agency is not inherently required to analyze impacts of a separate project that might foreseeably result from the project the agency is reviewing, particularly where those separate projects fall outside the agency’s regulatory authority.
Justice Kavanaugh delivered the opinion, and Chief Justice Roberts and Justices Thomas, Alito, and Barrett joined. Justice Sotomayor filed a concurring opinion, in which Justices Kagan and Jackson joined. Justice Gorsuch took no part in the consideration or decision of the case.
Background
In August 2021, the U.S. Surface Transportation Board (Board) prepared a 3,600 page EIS for the Seven County Infrastructure Coalition’s (the Coalition’s) proposed construction and operation of an 88-mile railroad line to connect Utah’s Uinta Basin to the national rail network to facilitate the transportation of crude oil from Utah to refineries in Louisiana, Texas, and elsewhere. The Board approved the project in December 2021.
The EIS noted, but did not fully analyze, the potential effects of increased upstream oil drilling in the Uinta Basin and increased downstream refining of crude oil carried by the railroad. The EIS did not analyze upstream drilling because (i) the project was not an oil well or drilling permit, (ii) the Board has no authority or control over potential future oil and gas development in the Uinta Basin and any such future projects would be subject to the approval processes of other agencies, and (iii) any such future development is speculative and attenuated from the railroad line project. The EIS also explained that downstream oil refining was not analyzed because (i) the Board was not privy to or in charge of the identity of the specific destinations for such projects, and (ii) the Board would have no role in approving or regulating the production, refining, or use of Uinta Basin crude oil.
A Colorado county and several environmental organizations filed petitions for review in the U.S. Court of Appeals for the D.C. Circuit. The D.C. Circuit vacated the Board’s EIS and approval, concluding that the Board failed to take the requisite “hard look” under NEPA at all of the environmental impacts—specifically the effects of upstream oil drilling and downstream oil refining which were “reasonably foreseeable impacts” that the EIS should have analyzed.
The Coalition and the Uinta Basin Railway sought review. The Supreme Court granted certiorari.
The United States Supreme Court’s Decision
The Supreme Court reversed the D.C. Circuit’s decision, concluding that the Board’s EIS was sufficient under NEPA. The Court explained that the D.C. Circuit did not afford the Board the substantial deference required in NEPA cases, and that the D.C. Circuit erroneously ordered the Board to address environmental effects outside the scope of what NEPA requires.
Agency Deference
The Court concluded that when determining whether an EIS complied with NEPA, courts should afford substantial deference to the agency pursuant to the “arbitrary-and-capricious” standard, under which a court asks only whether the agency action was reasonable and reasonably explained, regardless of whether it agrees with the agency’s decision.
The Court emphasized that NEPA is a purely procedural statute and imposes no substantive constraints on an agency’s ultimate decision on a project. The adequacy of an EIS is therefore relevant only to whether an agency’s final decision to approve the project was reasonably explained. In other words, courts should review an agency’s EIS to check that it addresses the environmental effects of the project at hand. In conducting that review, courts should afford substantial deference to the agency as to the scope and contents of the EIS.
The Court further explained that courts should not “micromanage” an agency’s choices regarding the length, content, and level of detail of the resulting EIS, so long as it falls within a “broad zone of reasonableness.” As specifically relevant here, courts should defer to agencies’ decisions about where to draw the line regarding (i) how far to go in considering indirect environmental effects from the project at hand and (ii) whether to analyze environmental effects from other projects separate in time or place from the project at hand.
The Court noted that court decisions that have not applied this level of deference have “slowed down or blocked many projects,” resulting in fewer and costlier projects.
Moreover, the Court held that an EIS deficiency may not necessarily require a court to vacate the agency’s approval of a project, at least absent reason to believe that the agency might disapprove the project if it added more to the EIS. In this case, it explained, even if the EIS drew the line on the effects of separate upstream or downstream projects too narrowly, that mistake would not require a court to vacate the approval of the project.
Analysis of Projects Separate in Time or Place
The Court determined that the D.C. Circuit erroneously required the Board to address environmental effects from projects separate in time or place from the railroad line. It stated that the Board’s decision to exclude the upstream oil drilling and downstream oil refining from the proposed project assessed in the EIS complied with NEPA and the Court’s NEPA precedents.
The Court explained that while NEPA might require analysis of the environmental effects of a project that extend outside the geographical territory of the project or occur later in time, if the project at issue might lead to the construction or increased use of a separate project—the agency need not consider the environmental effects of that separate project because the separate project breaks the chain of proximate causation. Effects from a separate project may be foreseeable, but that does not mean that they are relevant to the agency’s decisionmaking process or that it is reasonable to hold the agency responsible for those effects. Agencies may draw a “manageable line” that encompasses the effects of the project at hand, but not the effects of projects separate in time or place.
The Court emphasized that agencies are not required to analyze the effects of projects over which they do not exercise regulatory authority. If other projects are interrelated or close in time to the project at issue, the question is whether that other project is a single project within the authority of the agency at issue—a question that is also deferential to the agency.
Here, the Court concluded that the EIS correctly explained that the environmental effects of future upstream oil drilling are distinct from construction and operation of the railroad line, and that any effects from downstream oil refineries are outside the railroad project. The Court explained that more importantly, the Board has no regulatory authority over the separate upstream drilling and downstream refinery projects, as it does not regulate oil drilling, oil wells, oil and gas leases, or oil refineries, and there is no “reasonably close causal relationship” between the railroad line and the effects of the separate projects.
The Court stated that courts should strive for “clarity and predictability” in deciding cases involving the American economy, noting that some courts have failed to meet that objective. It also explained that citizens may not enlist federal courts to delay or block projects based on the environmental effects of other, separate projects, and that the political process is the appropriate forum in which to air such policy disagreements.
Concurring Opinion (Justice Sotomayor, joined by Justices Kagan and Jackson)
The concurring opinion explained that the majority’s analysis is unnecessarily grounded in matters of policy, and that legal precedent results in the same outcome.
Citing two previous SCOTUS cases, the concurrence reasoned that an agency is not responsible for environmental impacts it could not lawfully have acted to avoid, nor for impacts that are so causally attenuated from the agency’s statutorily assigned tasks that it could not reasonably have been expected to consider them as part of its decisionmaking process.
Here, the concurrence concluded, the Board’s organic statute, the Interstate Commerce Commission Termination Act, provides a clear presumption in favor of approving new railways, and confirms that the Board has no authority or jurisdiction over development of oil and gas in the Basin nor any authority to control or mitigate the impacts of any such development. Therefore, the Board correctly determined that it could not have rejected the railroad line application to prevent effects of oil drilling and refining.
– Veronika Morrison