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National Environmental Policy Act Review Process

The National Environmental Policy Act (NEPA) process begins when a federal agency develops a proposal to take a major federal action. These actions are defined at 40 CFR 1508.1.  The environmental review under NEPA can involve three different levels of analysis:

  1. Categorical Exclusion determination (CATEX)
  2. Environmental Assessment/Finding of No Significant Impact (EA/FONSI)
  3. Environmental Impact Statement (EIS)

Categorical Exclusion (CATEX)

A federal action may be "categorically excluded" from a detailed environmental analysis when the federal action normally does not have a significant effect on the human environment (40 CFR 1508.1(d)). The reason for the exclusion is generally detailed in NEPA procedures adopted by each federal agency.

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Environmental Assessment/Finding of No Significant Impact

A federal agency can determine that a Categorical Exclusion (CATEX) does not apply to a proposed action. The federal agency may then prepare an Environmental Assessment (EA). The EA determines whether or not a federal action has the potential to cause significant environmental effects.  Each federal agency has adopted its own NEPA procedures for the preparation of EAs. See NEPA procedures adopted by each federal agency.

Generally, the EA includes a brief discussion of:

  • The purpose and need for the proposed action
  • Alternatives (as required by section 102(2)(E) of NEPA)
  • The environmental impacts of the proposed action and alternatives
  • A listing of agencies and persons consulted.

Based on the EA, the following actions can occur:

  • If the agency determines that the action will not have significant environmental impacts, the agency will issue a Finding of No Significant Impact (FONSI). A FONSI is a document that presents the reasons why the agency has concluded that there are no significant environmental impacts projected to occur upon implementation of the action.
  • If the EA determines that the environmental impacts of a proposed Federal action will be significant, an Environmental Impact Statement is prepared.

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Environmental Impact Statements (EIS)

Federal agencies prepare an Environmental Impact Statement (EIS) if a proposed major federal action is determined to significantly affect the quality of the human environment. The regulatory requirements for an EIS are more detailed and rigorous than the requirements for an EA.

Summary of the EIS Process

  1. An agency publishes a Notice of Intent in the Federal Register. The Notice of Intent informs the public of the upcoming environmental analysis and describes how the public can become involved in the EIS preparation.

    This Notice of Intent starts the scoping process, which is the period in which the federal agency and the public collaborate to define the range of issues and potential alternatives to be addressed in the EIS. 
  2. A draft EIS is published for public review and comment for a minimum of 45 days.

    Upon close of the comment period, agencies consider all substantive comments and, if necessary, conduct further analyses.  
  3. A final EIS is then published, which provides responses to substantive comments.  

    Publication of the final EIS begins the minimum 30-day "wait period," in which agencies are generally required to wait 30 days before making a final decision on a proposed action.

    EPA publishes a Notice of Availability in the Federal Register, announcing the availability of both draft and final EISs to the public. Find EISs with open comments or wait periods.
  4. The EIS process ends with the issuance of the Record of Decision (ROD). The ROD:
  • explains the agency's decision,
  • describes the alternatives the agency considered, and
  • discusses the agency's plans for mitigation and monitoring, if necessary.

What is included in an EIS?

An EIS Includes:

  • Cover sheet: Includes, among other things,
    • the name of the lead agency and any cooperating agency
    • agency contact information
    • the title of the proposed action and its location
    • a paragraph abstract of the EIS
    • the date when comments must be received.
  • Summary: A summary of the EIS, including the major conclusions, area of disputed issues, and the issues to be resolved.
  • Table of Contents: Assists the reader in navigating through the EIS.
  • Purpose and need statement: Explains the reason the agency is proposing the action and what the agency expects to achieve.
  • Alternatives: Consideration of a reasonable range of alternatives that can accomplish the purpose and need of the proposed action.
  • Affected environment: Describes the environment of the area to be affected by the alternatives under consideration.
  • Environmental consequences: A discussion of the environmental effects and their significance.
  • Submitted alternatives, information, and analyses: A summary that identifies all alternatives, information, and analyses submitted by state, tribal, and local governments and other public commenters for consideration during the scoping process or in developing the final EIS.
  • List of preparers: A list of the names and qualifications of the persons who were primarily responsible for preparing the EIS.
  • Appendices (if required): Appendices provide background materials prepared in connection with the EIS.

For a detailed explanation read 40 CFR Part 1502.

When is a supplement to the EIS required?

A supplement to a draft or final EIS is required when any of the following occurs:

  • An agency makes substantial changes to the proposed action that are relevant to its environmental concerns.
  • There are significant new circumstances or information relevant to the environmental concerns that have bearing on the proposed action or its impacts.

If an agency decides to supplement its EIS, it prepares, publishes and files the supplemental EIS in the same fashion as a draft or final EIS.

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