Summary of Environmental Law in the United States

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7 Environmental Impact Assessment


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7.2 Determining the Scope of the EIA Process


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The lead agency with jurisdiction over the project determines the scope of the EIS. 40C.F.R. sec. 1501.7(a)(2). "Scope" is defined as the range of actions, alternatives, and impacts to be considered in an environmental impact statement. 40C.F.R. sec. 1508.25. In addition, during the scoping phase the lead agency will eliminate insignificant issues or issues covered by prior environmental reviews, allocate assignments among agencies, identify timing issues, and decide whether to set page or time limits. 40C.F.R sec. 1501.7(a) and (b).

The agency must consider three types of actions: connected actions, cumulative actions, and similar actions. Connected actions are those where: (1) one action automatically triggers another action; (2) an action cannot proceed unless other actions are taken previously or simultaneously; or (3) the actions are interdependent parts of a larger action and depend on the larger action for their justification. Cumulative actions are actions which, when viewed with other proposed actions, have cumulatively significant impacts. Similar actions are actions which, when viewed with other reasonably foreseeable or proposed agency actions, have similarities that provide a basis for evaluating their environmental consequences together, such as common timing or geography.

Three types of alternatives must also be considered in the scoping phase: the proposed action, other reasonable alternatives, and the "no action" alternative.

Three types of impacts should be considered for each alternative: direct, indirect, and cumulative impacts. Direct impacts are caused by the action and occur at the same time and place. 40C.F.R. sec. 1508.8(a). Indirect impacts are caused by the action but are removed in time or distance. 40C.F.R. sec. 1508.8(b). Cumulative impacts are defined as impacts that result from the incremental impact of the action when added to other past, present, and reasonably foreseeable future actions. 40C.F.R. sec. 1508.7.

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7.3 Contents of EIA Document


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NEPA requires that the EIA include information pertaining to: (1) the environmental impact of the proposed project; (2) any adverse environmental effects which cannot be avoided, should the proposal be implemented; (3) the relationship between local short-term uses of the environment and the maintenance and enhancement of long-term productivity; and (4) any irreversible and irretrievable commitment of resources necessary for implementing the proposed action. 42 U.S.C. sec. 4332(C). The EIA must also describe alternatives to the proposed project and possible measures for mitigating the environmental harms. See also 40 C.F.R. sec. 1502.16.


NEPA requires that every EIA include a detailed statement on alternatives to the proposed action. 42 U.S.C. sec.4332(2)(C)(iii). For each alternative, the agency must describe the direct, indirect, and cumulative impacts. 40 C.F.R. sec. 1508.25(c). The EIA should present the environmental impacts of the proposal and the alternatives in comparative form, providing clearly defined options from which to choose. The agency must evaluate all reasonable alternatives, including the alternative of no action, and identify the preferred alternative. 40 C.F.R. sec. 1502.14.


The EIA must also identify appropriate mitigation measures. 40 C.F.R. sec. 1502.14(f). The agency is not required to adopt mitigation measures, but it must explain why any practicable mitigation was not adopted. 40 C.F.R. sec. 1505.2(c). The lead agency must ensure the implementation of any mitigation measures upon which the final decision was conditioned. 40 C.F.R. sec. 1505.3.

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7.4 Decision-making and Post-Decision Monitoring


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NEPA regulations provide that "[a]gencies shall integrate the NEPA process with other planning at the earliest possible time, to insure that planning and decisions reflect environmental values, to avoid delays later in the process, and to head off potential conflicts."40 C.F.R. sec. 1501.2. The regulations also state that the EIA must be prepared early enough to contribute to the decision-making process and that the EIA may not be used to rationalize or justify decisions already made. 40 C.F.R. sec. 1502.5.

Agency Consultation

After the EIA has been completed, NEPA requires that agencies with related jurisdiction or special expertise be allowed to comment on issues in the EIA within their areas of competence. 40 C.F.R. sec. 1503.2. Each EIA is reviewed by the EPA. 40 C.F.R. sec. 1504.1(b). The lead agency must respond to all comments, including comments from the public, by: (1) modifying alternatives including the proposed action; (2) developing and evaluating new alternatives; (3) supplementing, improving, or modifying its analysis; (4) making factual corrections; and/or (5) explaining why the comments do not warrant further response. 42 U.S.C. sec. 4332(2); 40 C.F.R. sec. 1503.4(a). In general, a federal agency, after attempting to resolve its concerns about the EIA with the lead agency, remains convinced that an aspect of the EIA is "unsatisfactory from the standpoint of public health or welfare or environmental quality," the agency may refer the matter to the Council on Environmental Quality (CEQ). 40 C.F.R. sec. 1504.1(b). The CEQ may, among other actions, mediate between the lead and referring agencies and/or submit its own recommendations to the President for action. 40 C.F.R. sec. 1504.3.

Record of Decision

After the period for public comment has expired, the agency that prepared the EIA decides whether to proceed with the action. 40 C.F.R. sec. 1506.10. A record of decision (ROD) must be prepared and made public at the time of the decision. No decision on the proposed action may be taken until 60 days after the draft EIS is made available to the public or 30 days after public notification that the final EIS has been completed. 40 C.F.R. sec. 1506.10(b)(2). The ROD must state the basis for the agency's decision, identify all alternatives that were considered, specify the environmentally preferable alternative, and explain any requirements for avoiding or mitigating environmental harm. The agency is not required to select the environmentally preferable alternative, but it must explain its reasons for selecting a less environmentally protective alternative. 40 C.F.R. sec. 1505.2.

Post-Decision Monitoring

While NEPA generally does not require post-decision monitoring, it does require a "monitoring and enforcement program" for any required mitigation. 40 C.F.R. sec. 1505.2(c). Mitigation measures included in the ROD must be implemented by the lead agency or other appropriate consenting agency. Agencies must make the results of relevant mitigation monitoring available to the public. 40 C.F.R. sec. 1505.3.

State Environmental Impact Assessments

States may also supplement NEPA through state law. For example, California enacted the California Environmental Quality Act (CEQA), Cal. Pub. Res. Code sec. 21000 et seq., with which state and local public agencies must comply when undertaking a "project." Under this statute, a "project" is defined as an activity undertaken by a public agency or a private activity that must receive some discretionary approval. If an action is deemed to be a project, the agency must perform one of three reviews: (1) Negative Declaration if it finds no "significant" impacts; (2) Mitigated Negative Declaration if it finds "significant" impacts but revises the project to avoid or mitigate those impacts; or (3) Environmental Impact Report (EIR) if it finds "significant" impacts. The major difference between CEQA and NEPA is that under CEQA a project may not be approved as submitted if feasible alternatives or mitigation measures are able to substantially lessen the environmental effects of the project.

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If, after screening, the agency decides not to prepare an EIA, it must notify the affected public of its decision. 40 C.F.R. sec. 1501.4(e)(1). As early as practicable after deciding to prepare an EIS, and before beginning the scoping process, the agency must notify the public of its intent to prepare an EIA. Affected federal, state, and local agencies, Indian tribes, the proponent of the action, and other interested persons (including those who might oppose the action on environmental grounds) must be invited to participate in the scoping process. 40 C.F.R. sec. 1501.7; Council on Environmental Quality, Memorandum: Scoping Guidance (April 30, 1981).

The public must be given access to a broad range of information, including: all background information considered during scoping; the draft and final EIA along with all underlying information and any comments; 40 C.F.R. sec. 1506.6(f); the record of decision; 40 C.F.R. sec. 1505.2 and any mitigation monitoring results. 40 C.F.R. sec. 1505.3.

Any interested person or organization must be allowed to submit comments on a draft EIA. 40 C.F.R. sec. 1502.19(c), 40 C.F.R. sec.1503.1(a)(4). While agencies are not required to solicit comments on a final EIA, they must wait at least 30 days after publication before making a final decision on the proposal. During this period, the public may submit written comments on the EIA. 40 C.F.R. sec. 1503.1(b). The agency must respond to such comments and, with controversial matters, it should hold public hearings. 40 C.F.R sec. 1503.4(a); 40 C.F.R. sec. 1506.6(c)(1).

Citizens can seek judicial review of issues that are not resolved through public comment, but the U.S. Supreme Court has largely limited the grounds for challenging an EIA to procedural matters. As long as agencies follow the procedures set out in the NEPA regulations, most challenges to an EIA will not be sustained.

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