A Guide to the National Environmental Policy Act Requirements, Process, and Compliance

The National Environmental Policy Act (NEPA) is a critical piece of environmental legislation that has shaped federal decision-making and project planning for over 50 years. This comprehensive guide delves into the key aspects of NEPA, providing a clear and accessible resource for understanding its regulatory scope, compliance requirements, and practical implications. Readers will learn about the specific activities and entities regulated under NEPA, the environmental resources it protects, and the procedural requirements for assessing environmental impacts. The guide also explores the relationship between NEPA and other environmental regulations, as well as the roles of various federal agencies in its implementation. Through detailed explanations of the NEPA process, including the preparation of Environmental Assessments and Environmental Impact Statements, readers will gain a solid foundation for navigating this complex regulatory landscape. The guide also addresses important topics such as public participation, interagency coordination, and the potential consequences of non-compliance. By the end of this guide, readers will have a thorough understanding of NEPA's history, its current regulatory framework, and the tools and resources available for achieving compliance and promoting sustainable project development.


Key Details of the National Environmental Policy Act

Issuing Agency: Council on Environmental Quality
Year Established: 1970
Last Amended: 2020
Statutory Authority: National Environmental Policy Act of 1969
Primary Legal Reference: Title 40, Chapter V, Parts 1500-1508 of the Code of Federal Regulations

What is the National Environmental Policy Act?

The National Environmental Policy Act (NEPA) is a United States environmental law that establishes a broad national framework for protecting the environment. NEPA's basic policy is to assure that all branches of government give proper consideration to the environment prior to undertaking any major federal action that significantly affects the environment.[^1]

NEPA is administered by the Council on Environmental Quality (CEQ), which was established by the Act within the Executive Office of the President. The Environmental Protection Agency (EPA) and other federal agencies also play roles in the NEPA process.

Enacted in 1970, NEPA was one of the first laws that established the broad national framework for protecting the environment. The Act has been amended several times, with the most recent significant amendments occurring in 2020.

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
  • Constructing highways and other publicly-owned facilities[^2]

Using the NEPA process, agencies evaluate the environmental and related social and economic effects of their proposed actions.

What does the National Environmental Policy Act protect?

The National Environmental Policy Act (NEPA) protects a wide range of environmental resources from potential adverse impacts resulting from major federal actions. These resources include:

  1. Air quality
  2. Water quality
  3. Wildlife and their habitats
  4. Cultural and historic resources
  5. Social and economic resources

NEPA achieves this protection by requiring federal agencies to consider the environmental impacts of their proposed actions and to involve the public in the decision-making process. This is done through the preparation of Environmental Assessments (EAs) and Environmental Impact Statements (EISs), which assess the potential environmental effects of a proposed action and alternatives to that action.

By requiring this thorough evaluation and public involvement, NEPA aims to ensure that environmental resources are given appropriate consideration in federal decision-making, and that potential adverse impacts are identified, avoided, or mitigated to the extent possible.

[^1]: "What is the National Environmental Policy Act?" EPA, 2 Feb. 2023, https://www.epa.gov/nepa/what-national-environmental-policy-act [^2]: "National Environmental Policy Act Review Process." EPA, 2 Feb. 2023, https://www.epa.gov/nepa/national-environmental-policy-act-review-process


Regulated Activities and Entities

The National Environmental Policy Act (NEPA) applies to all federal agencies and their actions that may significantly affect the environment. This includes a wide range of activities, such as construction projects, resource management plans, and permit approvals. While NEPA does not prohibit any specific activities or substances, it requires federal agencies to evaluate the environmental impacts of their proposed actions and consider alternatives that may have less impact on the environment.

The following types of activities are typically subject to NEPA review:

  • Major federal construction projects, such as highways, dams, and power plants
  • Federal land management activities, including resource extraction, grazing, and logging
  • Federal permit and license approvals for private projects, such as oil and gas pipelines, transmission lines, and renewable energy facilities
  • Federal funding of state, local, or private projects, such as grants for infrastructure or community development

Key Sections of the National Environmental Policy Act

Section 101: Declaration of National Environmental Policy
  • Purpose: Establishes the national policy of protecting the environment and promoting harmony between humans and nature.
  • Key requirements: Federal agencies must use all practicable means to create and maintain conditions under which humans and nature can exist in productive harmony.
  • Significance: Sets the overall tone and purpose of NEPA, emphasizing the importance of environmental considerations in federal decision-making.
Section 102: Cooperation of Agencies; Reports; Availability of Information; Recommendations; International and National Coordination of Efforts
  • Purpose: Outlines the procedural requirements for federal agencies to incorporate environmental considerations into their decision-making processes.
  • Key requirements: Federal agencies must prepare detailed statements (Environmental Impact Statements) for major actions significantly affecting the environment, consult with other agencies, and make information available to the public.
  • Significance: Establishes the core procedural requirements of NEPA, ensuring that federal agencies evaluate and disclose the environmental impacts of their actions.
  • Related processes: Environmental Assessments (EA) and Environmental Impact Statements (EIS).
Section 105: Efforts Supplemental to Existing Authorizations
  • Purpose: Clarifies that NEPA's policies and goals supplement, but do not replace, the existing mandates of federal agencies.
  • Significance: Emphasizes that NEPA is an additional layer of environmental review, and does not supersede other laws or regulations governing federal agency actions.

Relationship to Other Regulations & Agencies

NEPA interacts with numerous other federal, state, and local regulations and agencies. Many federal agencies have developed their own NEPA implementation procedures that are tailored to their specific missions and activities. For example, the Environmental Protection Agency (EPA) has a significant role in reviewing and commenting on Environmental Impact Statements prepared by other federal agencies.

In addition, NEPA often intersects with other federal environmental laws, such as the Clean Air Act, Clean Water Act, and Endangered Species Act. When a proposed federal action triggers multiple environmental laws, the NEPA process can serve as an umbrella framework for coordinating compliance with these other requirements.

State and local governments may also have their own environmental review processes that parallel or complement NEPA. In some cases, federal agencies may collaborate with state and local agencies to prepare joint environmental documents that satisfy both federal and state requirements.


Regulatory Standards & Limitations

The National Environmental Policy Act (NEPA) establishes procedural requirements for federal agencies to assess the environmental impacts of their proposed actions.1 NEPA does not set specific emissions limits, performance standards, or other quantitative metrics. Instead, it requires agencies to consider the potential environmental consequences of their decisions and to involve the public in the decision-making process.2

Under NEPA, federal agencies must prepare an Environmental Assessment (EA) or an Environmental Impact Statement (EIS) for major federal actions that may significantly affect the quality of the human environment.3 The Council on Environmental Quality (CEQ) regulations implementing NEPA define "major federal action" to include actions with effects that may be major and which are potentially subject to federal control and responsibility, such as the adoption of official policy, formal plans, programs, or the approval of specific projects.4

The EA is a concise public document that provides sufficient evidence and analysis to determine whether to prepare an EIS or a Finding of No Significant Impact (FONSI).5 If the EA concludes that the proposed action will not have significant environmental impacts, the agency may issue a FONSI. If the EA indicates that the impacts may be significant, the agency must prepare an EIS.6

The EIS is a detailed document that evaluates the proposed action and its alternatives, assesses the environmental impacts of each alternative, and identifies mitigation measures to minimize adverse impacts.7 The EIS process includes multiple opportunities for public participation, including scoping, comment on the draft EIS, and administrative appeals.8

Agencies must consider three types of impacts in their NEPA analyses: direct, indirect, and cumulative.9 Direct impacts are caused by the action and occur at the same time and place. Indirect impacts are caused by the action but occur later in time or farther removed in distance. Cumulative impacts result from the incremental impact of the action when added to other past, present, and reasonably foreseeable future actions.10

NEPA's procedural requirements are enforced through judicial review. If an agency fails to comply with NEPA, a court may enjoin the proposed action pending completion of the required environmental review.11

Monitoring, Reporting & Recordkeeping Obligations

NEPA itself does not impose specific monitoring, reporting, or recordkeeping requirements on regulated entities. However, the EIS process generates a substantial administrative record that documents the agency's decision-making process and its consideration of environmental impacts.12

This record typically includes:

  • The draft and final EIS documents
  • Public comments and agency responses
  • Technical studies and supporting documentation
  • Records of public hearings and meetings
  • The Record of Decision (ROD) explaining the agency's final decision13

Agencies must maintain this administrative record and make it available to the public upon request, subject to certain exceptions for privileged or confidential information.14

In some cases, the ROD or other decision documents may require ongoing monitoring, reporting, or mitigation measures as a condition of project approval. These requirements are typically project-specific and may include obligations such as:

  • Monitoring of environmental parameters (e.g., air quality, water quality, wildlife populations)
  • Reporting of monitoring results to the agency or the public
  • Implementation of mitigation measures to minimize or compensate for environmental impacts15

These post-decision requirements are important for ensuring that the environmental impacts of the project are adequately managed and that the agency's decision is based on accurate and up-to-date information.

Enforcement Actions & Penalties

The Environmental Protection Agency (EPA) and other federal agencies with NEPA responsibilities may conduct inspections or audits to ensure that agencies are complying with NEPA's procedural requirements. These compliance reviews may be triggered by complaints, referrals from other agencies, or as part of a routine oversight program.16

Inspections may involve a review of the agency's NEPA documentation, interviews with agency staff, and site visits to assess the accuracy and completeness of the environmental analysis. The scope of the inspection may cover a specific project or a programmatic review of the agency's NEPA compliance practices.17

If an agency is found to be in violation of NEPA, the enforcement agency may take a range of actions, including:

Enforcement ActionDescription
Administrative OrderA formal directive requiring the agency to take specific corrective actions, such as preparing a supplemental EIS or modifying its decision.
Civil PenaltiesMonetary fines assessed by the enforcement agency for NEPA violations. The amount of the penalty may be based on factors such as the severity of the violation, the economic benefit derived from the violation, and the agency's compliance history.
Criminal ChargesIn rare cases, individuals or agencies may face criminal charges for willful or knowing violations of NEPA, such as falsifying or concealing information in an EIS.
Injunctive ReliefA court order requiring the agency to take specific actions or refrain from taking certain actions pending compliance with NEPA.

The severity of the enforcement action will depend on factors such as the nature and extent of the violation, the agency's willingness to correct the violation, and the environmental harm or risk associated with the violation.18

Regulated entities have certain rights and responsibilities during NEPA inspections, including the right to be informed of the purpose and scope of the inspection, the right to have an attorney or representative present during the inspection, and the responsibility to provide access to records and facilities as required by law.19

Compliance Assistance & Regulatory Incentives

Several federal agencies offer compliance assistance programs and incentives to help agencies and regulated entities understand and comply with NEPA's requirements. These include:

  1. Technical Assistance: The Council on Environmental Quality (CEQ) provides guidance documents, handbooks, and other resources to help agencies interpret and apply NEPA's requirements.20 These resources cover topics such as scoping, alternatives analysis, cumulative impact assessment, and public participation.

  2. Training and Workshops: CEQ and other agencies offer training courses and workshops on NEPA compliance for federal employees and contractors. These training sessions cover the legal and policy framework of NEPA, the steps in the EIS process, and best practices for effective environmental analysis and public involvement.

  3. Online Resources: Many agencies maintain online NEPA libraries and databases that provide access to EIS documents, guidance materials, and other resources.21 These online tools can help regulated entities and the public navigate the NEPA process and find relevant information for their projects.

  4. Interagency Coordination: CEQ and other agencies have established interagency working groups and committees to promote consistency and efficiency in NEPEA compliance across the federal government. These groups develop streamlined procedures, share best practices, and resolve common challenges in the NEPA process.

  5. Pilot Projects and Demonstrations: Some agencies have launched pilot projects or demonstration programs to test innovative approaches to NEPA compliance, such as programmatic EISs, tiered analyses, or landscape-scale assessments. These projects aim to reduce duplication, improve decision-making, and accelerate project delivery while maintaining environmental protections.

  6. Recognition Programs: A few agencies have established recognition or awards programs to highlight exemplary NEPA analyses or practices. These programs aim to encourage innovation, share success stories, and promote a culture of environmental stewardship in federal decision-making.

While NEPA does not provide direct financial incentives for compliance, some agencies may offer expedited review or other process benefits for projects that demonstrate superior environmental performance or collaborative approaches to NEPA compliance.

Agencies and regulated entities can access these compliance assistance resources through the websites and contact points of CEQ and the relevant federal agencies. Many of these resources are available free of charge, while some training courses may require a registration fee.


Regulatory History & Upcoming Changes

The National Environmental Policy Act (NEPA) was signed into law on January 1, 1970, by President Richard Nixon. It established a national policy for the environment and provided a framework for environmental planning and decision-making by federal agencies. The key provisions of NEPA include[^300]:

  1. Requiring federal agencies to assess the environmental impacts of their proposed actions before making decisions.
  2. Mandating the preparation of an Environmental Impact Statement (EIS) for major federal actions significantly affecting the quality of the human environment.
  3. Establishing the Council on Environmental Quality (CEQ) to oversee NEPA implementation and develop regulations and guidance.

Since its enactment, NEPA has undergone several amendments and regulatory changes. Some of the most significant updates include:

  • The 1978 CEQ regulations, which provided detailed guidance on implementing NEPA and preparing EISs[^301].
  • The 1981 "scoping" process, which requires agencies to engage the public and other stakeholders early in the NEPA process to identify issues and alternatives[^302].
  • The 2020 CEQ regulations, which aimed to streamline the NEPA process, establish time limits for environmental reviews, and promote coordination among agencies[^303].

These changes have been driven by various political and environmental factors, such as the need to balance economic development with environmental protection, the desire to reduce delays and litigation in the NEPA process, and the increasing recognition of the importance of public participation and environmental justice.

As of 2023, there are ongoing efforts to revise the 2020 CEQ regulations and restore certain provisions from the 1978 regulations. In April 2022, the CEQ issued a final rule revising the 2020 regulations, which aims to enhance public participation, improve coordination among agencies, and promote more efficient and effective environmental reviews[^304]. Regulated entities should stay informed about these changes and engage in the public comment process to ensure their interests are considered.

Additional Resources

  1. Full text of the National Environmental Policy Act and its amendments
  2. CEQ NEPA Regulations (40 CFR Parts 1500-1508)
  3. CEQ guidance documents and handbooks
  4. EPA's NEPA website [^308] offers a wealth of information on NEPA, including agency-specific guidance, case studies, and training materials.
  5. "The NEPA Book: A Step-by-Step Guide on How to Comply with the National Environmental Policy Act" by Ronald E. Bass, Albert I. Herson, and Kenneth M. Bogdan[^309] - A comprehensive guide to NEPA compliance, with practical advice and real-world examples.
  6. "NEPA and Environmental Planning: Tools, Techniques, and Approaches for Practitioners" by Charles H. Eccleston[^310] - An in-depth exploration of the NEPA process, with a focus on effective environmental planning and decision-making.

[^300]: "Summary of the National Environmental Policy Act." EPA, https://www.epa.gov/laws-regulations/summary-national-environmental-policy-act [^301]: "Regulations for Implementing the Procedural Provisions of the National Environmental Policy Act." Federal Register, 29 Nov. 1978, https://www.federalregister.gov/documents/1978/11/29/C8-29821/regulations-for-implementing-the-procedural-provisions-of-the-national-environmental-policy-act [^302]: "Forty Most Asked Questions Concerning CEQ's National Environmental Policy Act Regulations." Council on Environmental Quality, 23 Mar. 1981 [^303]: "Update to the Regulations Implementing the Procedural Provisions of the National Environmental Policy Act." Federal Register, 16 July 2020, https://www.federalregister.gov/documents/2020/07/16/2020-15179/update-to-the-regulations-implementing-the-procedural-provisions-of-the-national-environmental [^304]: "National Environmental Policy Act Implementing Regulations Revisions." Federal Register, 20 Apr. 2022, https://www.federalregister.gov/documents/2022/04/20/2022-08288/national-environmental-policy-act-implementing-regulations-revisionsHaney2. [^308]: "National Environmental Policy Act Review Process." EPA, https://www.epa.gov/nepa [^309]: Bass, Ronald E., et al. "The NEPA Book: A Step-by-Step Guide on How to Comply with the National Environmental Policy Act." Solano Press Books, 2001. [^310]: Eccleston, Charles H. "NEPA and Environmental Planning: Tools, Techniques, and Approaches for Practitioners." CRC Press, 2008.


  1. 42 U.S.C. § 4321 et seq.

  2. 40 C.F.R. § 1500.1(a)

  3. 42 U.S.C. § 4332(2)(C)

  4. 40 C.F.R. § 1508.18

  5. 40 C.F.R. § 1508.9

  6. 40 C.F.R. § 1501.4

  7. 40 C.F.R. § 1502

  8. 40 C.F.R. § 1503, 1506.6

  9. 40 C.F.R. § 1508.7, 1508.8

  10. 40 C.F.R. § 1508.7

  11. 5 U.S.C. § 706

  12. 40 C.F.R. § 1505.1

  13. 40 C.F.R. § 1505.2

  14. 5 U.S.C. § 552

  15. 40 C.F.R. § 1505.3

  16. EPA, "National Environmental Policy Act Compliance Audit Program,"

  17. Ibid.

  18. CEQ, "Memorandum for Heads of Federal Departments and Agencies: Reporting Violations of the National Environmental Policy Act,"

  19. EPA, "National Environmental Policy Act Compliance Audit Program,"

  20. CEQ, "NEPA Guidance and Requirements," https://ceq.doe.gov/guidance/guidance.html

  21. See, e.g., EPA, "Environmental Impact Statement (EIS) Database," https://cdxnodengn.epa.gov/cdx-enepa-public/action/eis/search

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A Note to Our Readers: We hope this guide is a valuable resource in helping you better understand the NEPA. However, it's not a substitute for professional advice and doesn't cover every scenario. Always consult with regulatory bodies and professionals for the most current advice and project-specific guidance.