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What is the National Environmental Policy Act?

The National Environmental Policy Act (NEPA) was signed into law on January 1, 1970. NEPA requires federal agencies to assess the environmental effects of their proposed actions prior to making decisions. The range of actions covered by NEPA is broad and includes:

  • making decisions on permit applications,
  • adopting federal land management actions, and
  • constructing highways and other publicly-owned facilities.

Using the NEPA process, agencies evaluate the environmental and related social and economic effects of their proposed actions. Agencies also provide opportunities for public review and comment on those evaluations.

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Title I of NEPA contains a Declaration of National Environmental Policy. This policy requires the federal government to use all practicable means to create and maintain conditions under which man and nature can exist in productive harmony.

Section 102 in Title I of the Act requires federal agencies to incorporate environmental considerations in their planning and decision-making through a systematic interdisciplinary approach. Specifically, all federal agencies are to prepare detailed statements assessing the environmental impact of and alternatives to major federal actions significantly affecting the environment. These statements are commonly referred to as Environmental Impact Statements (EIS) and Environmental Assessments (EA).

Title II of NEPA established the President's Council on Environmental Quality (CEQ) to oversee NEPA implementation. The duties of CEQ include:

  • Ensuring that federal agencies meet their obligations under NEPA
  • Overseeing federal agency implementation of the environmental impact assessment process
  • Issuing regulations and other guidance to federal agencies regarding NEPA compliance.

Learn more about the National Environmental Policy Act.

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How do federal agencies carry out the NEPA requirements?

In 1978, CEQ issued regulations (40 CFR Parts 1500-1508) to implement NEPA. These regulations are binding on all federal agencies. The regulations address the procedural provisions of NEPA and the administration of the NEPA process, including the preparation of environmental impact statements. In addition to the CEQ NEPA regulations, CEQ has issued a variety of guidance documents on the implementation of NEPA.

Many federal agencies have also developed their own NEPA procedures that supplement the CEQ NEPA regulations. These NEPA procedures vary from agency to agency since they are tailored for the specific mission and activities of the agency. Find NEPA procedures for specific federal agencies.

Lead Agency

The role of a federal agency in the NEPA process depends on the agency's expertise and relationship to the proposed action. The agency carrying out the federal action is responsible for complying with the requirements of NEPA. In some cases, there may be more than one federal agency involved in the proposed action. In this situation, a lead agency is designated to supervise the preparation of the environmental analysis. Federal agencies, together with state, tribal or local agencies, may act as joint lead agencies.

Cooperating Agency

A federal, state, tribal or local agency having special expertise with respect to an environmental issue or jurisdiction by law may be a cooperating agency. A cooperating agency has the responsibility to:

  • assist the lead agency by participating in the NEPA process at the earliest possible time
  • participate in the scoping process
  • develop information and prepare environmental analysis that the agency has special expertise in
  • make staff support available

Referrals to CEQ

In addition, a federal agency may refer to CEQ interagency disagreements concerning proposed federal actions that might cause unsatisfactory environmental effects. CEQ's role, when it accepts a referral, is generally to develop findings and recommendations, consistent with the policy goals of Section 101 of NEPA. The referral process consists of certain steps and is carried out within a specified period. Learn more about CEQ's referral process (PDF) (4 pp, 40 K, About PDF).

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