In 1978, eight years following the enactment of NEPA, the President's Council on Environmental quality (CEQ) released its formal regulations guiding agency compliance with the Act. Found in Title 40 parts 1500-1508 of the United States Code, the Council's regulations were designed to ensure that federal agencies "act according to the letter and spirit of the Act". Specifically, the regulations tell agencies what they must do to comply with section 102(2) of NEPA (42 USC §4332). As issues have arisen, the Council has also developed informal guidance and studies to further aid agencies and the public in compliance with the Act. In addition, each federal agency has its own NEPA procedures. To learn more about individual agency procedures click here.

On July 16, 2020 the CEQ completed the first comprehensive revision of NEPA regulations in 40 years. The update’s intent was to “to modernize provisions, streamline infrastructure project development, and promote better decision making by the Federal government.”(CEQ 2020). The National Law Review analyzes these changes. Agencies begin implementing the new changes end of September, 2020. 

Three Levels of Environmental Review and Compliance

The NEPA process has been conceptualized as having three distinct levels of environmental review and compliance (Eccleston 1999, 49; Fogleman 1990, 40). Agencies must specify criteria for and identify classes of actions that normally fall within each of these levels of review (40CFR 1507.3b). For a graphic illustrating the NEPA process click here.

1. Categorical Exclusion (CATX) (definition ): These are actions that have been determined by the agency to not individually or cumulatively have a significant effect on the human environment and thus, in the absence of extraordinary circumstances, do not require an environmental impact statement or an environmental assessment. Actions that qualify for a CATX are exempt from further NEPA review unless extraordinary circumstances are present (40 CFR 1507.3b, 1508.4).
2. Environmental Assessment (EA) (definition ): An EA is a concise public document that provides evidence and analysis of actions and alternatives for determining whether to prepare an environmental impact statement or a finding of no significant impact (FONSI) (definition ). A FONSI is a document which explains the reasons why an action not otherwise excluded will not have a significant effect on the human environment (40 CFR 1508.9, 1508.13).
3. Environmental Impact Statement (EIS) (definition ): The EIS requires the highest level of environmental review and is prepared for actions that will have significant environmental impacts. The statement must comply with section 102 (2)(C)  of the Act as well as CEQ's regulations.

NEPA on Federal Rangelands

Federal agencies are given broad discretionary authority to determine policies and procedures for compliance with NEPA. This flexibility allows each agency to tailor procedures and criteria to its unique situation and needs. Thus, according to the varied mission of each agency the NEPA process may be different. With advances in technology, increasingly complex environmental problems, and protracted disputes over natural resources, agencies have recognized the need to update procedures to meet new challenges. The USDA Forest Service’s NEPA regulation revision process is documented on their NEPA site.