A. National Environmental Policy Act

Congress enacted the National Environmental Policy Act (NEPA) to declare a national policy “to use all practicable means and measures, including financial and technical assistance, in a manner calculated to foster and promote the general welfare, to create and maintain conditions under which man and nature can exist in productive harmony, and [to] fulfill the social, economic, and other requirements of present and future generations of Americans.” 42 U.S.C. 4331(a).

NEPA, as amended by the Fiscal Responsibility Act of 2023 (FRA), furthers this national policy by requiring federal agencies to prepare a “detailed statement” for proposed “major Federal actions significantly affecting the quality of the human environment.” P. L. No. 118-5.

This Environmental Impact Statement (EIS), as it has become known, must address:

1. The reasonably foreseeable environmental effects of the proposed agency action;
2. the reasonably foreseeable adverse environmental effects that cannot be avoided;
3. a reasonable range of alternatives to the proposed agency action, including an analysis of any negative environmental impacts of not implementing the proposed agency action in the case of a no action alternative, that are technically and economically feasible, and meet the purpose and need of the proposal;
4. the relationship between local short-term uses of man's environment and the maintenance and enhancement of long-term productivity; and
5. any irreversible and irretrievable commitments of resources that would be involved in the proposed action.

NEPA further mandates that federal agencies ensure the professional and scientific integrity of environmental documents; use reliable data and resources when carrying out NEPA; and study, develop, and describe technically and economically feasible alternatives.

In doing so, NEPA provides procedures for making threshold determinations about whether an environmental document must be prepared and the appropriate level of environmental review.

NEPA is a procedural statute, not a substantive one. NEPA does not mandate particular results, rather it requires federal agencies to consider the environmental effects of proposed actions as part of agencies' decision-making processes. The FRA amendments sought to improve NEPA in the creation of additional requirements meant to facilitate timely and unified federal review.

These amendments include provisions clarifying lead, joint lead, and cooperating agency designations; generally requiring the development of a single environmental document; directing agencies to develop procedures for project sponsors to prepare environmental assessments and environmental impact statements; and prescribing page limits and deadlines.

These amendments also expedite the review process by allowing reliance on “programmatic” environmental documents and adopt and use another agency’s categorical exclusions.

Until recently, federal courts, including the Supreme Court, have construed NEPA to require consideration of all “reasonably foreseeable” indirect effects of major federal infrastructure projects. Since the earliest cases interpreting NEPA, courts have consistently held that NEPA “plainly contemplates consideration of both the long- and short-range implications to man.” Scientists’ Inst. For Pub. Info., Inc. v. Atomic Energy Comm’n, 481 F.2d 1079, 1090 (D.C. Cir. 1973).

Congress codified this standard in its 2023 NEPA amendments (via the FRA) which clarified that EISs should analyze all “reasonably foreseeable environmental effects of the proposed agency action” and “any reasonably foreseeable adverse environmental effects which cannot be avoided should the proposal be implemented.” Pub. L. No. 118-16.

B. Council on Environmental Quality

The Council on Environmental Quality (CEQ) historically issued regulations outlining how federal agencies can comply with NEPA. Those rules provided a single framework for project proponents while giving flexibility to each agency. Agencies could then adopt their own NEPA implementing procedures, which would be reviewed by CEQ.

CEQ in February 2025 issued an interim final rule to remove the existing implementing regulations for NEPA. This deregulation was in response to Executive Order 14154, “Unleashing American Energy” (which rescinded E.O. 11991, “Relating to Protection and Enhancement of Environmental Quality,” which itself had amended E.O. 11514, “Protection and Enhancement of Environmental Quality”). These actions directed CEQ to promulgate regulations for implementing NEPA, required Federal agencies to comply with those regulations, directed CEQ to issue guidance on implementing NEPA, and directed CEQ propose rescinding the NEPA implementing regulations.

The interim final rule carried out President Trump's instruction to rescind the long-established CEQ regulations and the Biden Administration proposed reform rules. CEQ also conceded, based on a D.C. Circuit court challenge (Marin Audubon Society v. Federal Aviation Administration) and the wishes of the Administration, that it may lack authority to issue binding rules on agencies in the original Executive Order in 1978.

CEQ has since revoked these regulations implementing NEPA. In the absence of CEQ guidelines, each Federal agency must submit its own interpretation guidelines by February 2026. The first proposed agency guidelines were released in July 2025. The result: a patchwork of NEPA guidelines created by self-interested agencies.

It would be wise to forget what you learned about NEPA and the CEQ regulations in law school, during the last 75 years, or before February 2025. That was then, this is now. You’ll also want to reassess the holdings and import of prior Supreme Court and Circuit Court decisions.

On that score a related article addresses the recent Supreme Court decision on May 29, 2025, which significantly impacted how agencies comply with NEPA. The case is Seven County Infrastructure Coalition v. Eagle County et al, 605 U.S. (No. 23-975, May 29, 2025). There is a new set of principles that courts owe substantial discretion to agencies on many judgments they make on NEPA compliance and that NEPA does not require full coverage of all the upstream and downstream effects of projects, proposals and permits under review.