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Tennessee Environmental Procedures Manual

Chapter 1: Environmental Regulations and The Environmental Evaluation Process

1.1 Federal Regulations

1.1.1. National Environmental Policy Act (NEPA)

The United States Congress enacted the National Environmental Policy Act of 1969 (NEPA) to establish a national policy to protect the environment. The act is codified in Title 42 of the United States Code, Sections 4321 through 4347 (abbreviated as 42 USC 4321-4347). 1 On January 1, 1970, NEPA was signed into law by President Richard Nixon.

As set forth in the Act, the purposes of NEPA are:

[t]o declare a national policy which will encourage productive and enjoyable harmony between man and his environment; to promote efforts which will prevent or eliminate damage to the environment and biosphere and stimulate the health and welfare of man; to enrich the understanding of the ecological systems and natural resources important to the Nation; and to establish a Council on Environmental Quality.

NEPA requires federal agencies to consider environmental issues prior to making any major decisions on projects that have federal involvement (e.g., funding or permitting). To determine a project's potential benefit or harm to the environment, NEPA requires an assessment of environmental impacts and an evaluation of alternatives to avoid any identified adverse impacts to the environment.

The foundation of the NEPA process is summarized as follows:

Agencies of the Federal Government shall --

  • Utilize a systematic, interdisciplinary approach in planning and in decision- making that may have an impact on man's environment;
  • Include in every recommendation or report on proposals for legislation and other major Federal actions significantly affecting the quality of the human environment, a detailed statement by the responsible official on --
    1. The environmental impact of the proposed action;
    2. Any adverse environmental effects that cannot be avoided should the proposal be implemented;
    3. Alternatives to the proposed action;
    4. The relationship between local short-term uses of man's environment and the maintenance and enhancement of long-term productivity; and
    5. Any irreversible and irretrievable commitments of resources that would be involved in the proposed action should it be implemented.
  • Prior to making any detailed statement, the responsible federal official shall consult with and obtain the comments of any federal agency that has jurisdiction by law or special expertise; and
  • Make them available to the public.

Sections 4321 through 4335 of 42 USC, which address the National Environmental Policy, are reprinted in Appendix B [pdf 1.50 MB] to this manual.

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1.1.2 Council on Environmental Quality

The Council on Environmental Quality (CEQ) was created by NEPA to oversee the federal implementation of NEPA, by interpreting the law and developing regulations and guidance. The CEQ is housed within the Executive Office of the President. It has four main functions:

  • Develop environmental policies for the nation;
  • Monitor environmental quality;
  • Prepare an annual environmental quality report; and
  • Monitor federal actions relative to NEPA.

To assist federal agencies in effectively implementing the environmental policies of NEPA, the CEQ issued guidance through the Regulations for Implementing the Procedural Provisions of the National Environmental Policy Act , which is contained in the Code of Federal Regulation , Title 40, Parts 1500 through 1508 (abbreviated as 40 CFR 1500 -1508) in 1978. 2 The regulations state that NEPA procedures must ensure that environmental information is available to public officials and citizens before decisions are made and before actions are taken. The regulations also spell out the three categories of actions (Categorical Exclusions, Environmental Assessments, and Environmental Impact Statements), as well as documentation requirements and format, the commenting process and public involvement requirements, and document filing requirements. Lastly, CEQ regulations require each federal agency to develop their own regulations for agency compliance with NEPA.

In March 1983, CEQ issued the guidance document, Forty Most Asked Questions Concerning CEQ's NEPA Regulations. CEQ has since issued additional guidance and other information covering a variety of issues relevant to the NEPA process. The CEQ NEPAnet website,, contains these guidances and references.

The CEQ regulations and the Forty Questions guidance document are included in Appendix B [pdf 1.50 MB] of this manual.

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1.1.3 Federal Highway Administration Environmental Impact and Related Procedures

To address the NEPA responsibilities established by CEQ, two U.S. Department of Transportation (USDOT) agencies, the Federal Highway Administration (FHWA) and the Federal Transit Administration (FTA), have developed detailed guidance for applying NEPA to highway and transit projects. Those regulations are codified in 23 CFR 771, Environmental Impact and Related Procedures, as amended.

The regulations require that agencies undertaking transportation activities with federal funding or major federal action:

  • Comply with all applicable environmental requirements, including NEPA and Section 4(f) of the Department of Transportation Act of 1966;
  • Prepare documentation of compliance to a level appropriate to the undertaking's potential to cause significant harm to the environment;
  • Evaluate alternatives (including a no action or no-build alternative) and make decisions that balance the need for the project with the social, economic and environmental impacts of the project;
  • Inform governmental entities and the public and provide them an opportunity to be involved in decision-making; and
  • Implement measures to avoid, minimize or mitigate environmental impacts.

Section 771.115 of 23 CFR defined the three classes of actions that determine how compliance with NEPA is carried out and documented for transportation projects:

  • Class I - Environmental Impact Statement (EIS) is prepared for projects that will cause a significant adverse effect on the environment;
  • Class II - Categorical Exclusion (CE) is prepared for projects that cause minimal social, economic or environmental impact; and
  • Class III - Environmental Assessment (EA) is prepared for larger scale projects that do not meet the requirements for a CE or those for which the significance of the environmental impact is not clearly established. Should environmental analysis and interagency review during the EA process find a project to have no significant impacts on the quality of the environment, a Finding of No Significant Impact (FONSI) is issued. If it is found that the project will have significant impacts, an EIS must be prepared.

The levels of environmental documents are described in more detail in Chapter 3, NEPA Process Options and in Chapter 6, Prepare Environmental Documentation of this Manual.

On October 30, 1987, the FHWA issued guidance complementing the regulations in the form of a Technical Advisory (T 6640.8a), Guidance for Preparing and Processing Environmental and Section 4(f) Documents (hereafter referred to as the Technical Advisory). The Technical Advisory provides detailed information on the contents and processing of environmental documents. T6640.8a is included in its entirety as Appendix D [pdf 201 kb] of this Manual.

In addition to the Technical Advisory, FHWA has issued a number of guidances on specific topics (for example, air quality, noise, context sensitive solutions, bicycle and recreational planning). Links for these guidances can be found at Additional guidance and information on the NEPA process and other environmental requirements are found in the FHWA's Environmental Guidebook website at

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1.1.4 SAFETEA-LU 2005

In August, 2005, President George W. Bush signed into law the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (known as SAFETEA-LU). SAFETEA-LU incorporated changes aimed at improving and streamlining the environmental process for transportation projects. SAFETEA-LU established a new environmental review process for highways, transit, and multimodal projects developed as EISs; all EISs for which the Notice of Intent (NOI) was published after August 10, 2005 must follow the new requirements. The new process requirements emerging from Section 6002 of SAFETEA-LU are:

  • The project sponsor must send FHWA a project initiation letter prior to initiating the NEPA process;
  • The FHWA shall serve as the Federal lead agency for a transportation project. Any project sponsor that is a State or local government entity receiving federal-aid funds shall serve as a joint lead agency;
  • The lead agencies must invite all Federal, State, tribal, regional and local government agencies that have an interest in the project to be participating agencies;
  • Lead agencies must develop a coordination plan for public and agency participation and comment during the environmental review process; and
  • Participating agencies and the public must be given an opportunity for input in the development of the purpose and need and the range of alternatives. Lead agencies must collaborate with participating agencies on the appropriate methodologies to be used.

Section 6002 also establishes a 180-day statute of limitations (SOL) on claims against USDOT and other Federal agencies for certain environmental and other approval actions. The SOL established by SAFETEA-LU applies to a permit, license, or approval action by a Federal agency if: the action relates to a transportation project; and a SOL notification is published in the Federal Register announcing that a Federal agency has taken an action on a transportation project that is final under the Federal law pursuant to which the action was taken. If no SOL notice is published, the period for filing claims is not shortened from what is provided by other parts of Federal law.

The SOL provision is intended to expedite the resolution of issues affecting transportation projects. Whether a SOL notice is needed or is the best way to achieve such resolution on a project is a risk management decision. A determination should include consideration of the nature of the Federal laws under which decisions were made for the project, the actual risk of litigation, and the potential effects if litigation were to occur several years after the FHWA NEPA decision or other Federal agency decisions. A SOL notice can be used for a highway project regardless of the category of documentation used under NEPA. FHWA anticipates that it will publish notices for most EIS projects and many EA projects. FHWA does not expect SOL notices to be used for projects that are CEs under 23 CFR 771.117(c). FHWA anticipates that the notice may be appropriate for documented CE projects under 23 CFR.771.117(d).

FHWA's final guidance to implement the requirements of SAFETEA-LU Section 6002 and the environmental review process was published in the Federal Register on November 15, 2006. The guidance can be found on the FHWA website: A copy of SAFETEA-LU Section 6002 is included in Appendix B [pdf 1.50 MB].

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1.1.5 Other Regulations Related to NEPA

The NEPA process provides a framework, or "umbrella", for compliance with other environmental guidelines and regulations. Many other federal and state regulations fall under the NEPA umbrella and are discussed later in this manual in the applicable sections. Examples include, but are not limited to:

  • Title VI of the Civil Rights Act of 1964;
  • Uniform Relocation Assistance and Real Property Acquisition Policies Act of 1970;
  • Americans with Disabilities Act;
  • Executive Order 12898 (Environmental Justice);
  • Section 4(f) of the Department of Transportation Act;
  • Clean Air Act;
  • Safe Drinking Water Act;
  • Farmland Protection Policy Act;
  • Solid Waste Disposal Act;
  • Resource Conservation and Recovery Act of 1976;
  • Comprehensive Environmental Response, Compensation and Liability Act;
  • National Historic Preservation Act;
  • Archaeological and Historic Preservation Act;
  • Archaeological Resources Protection Act;
  • Section 6(f) of the Land and Water Conservation Act;
  • Endangered Species Act;
  • Executive Order 11988 (Floodplain Management); and
  • Executive Order 11990 (Protection of Wetlands).

Appendix C [pdf 67 kb] of this manual presents a matrix of many of the federal regulations that must be considered in the environmental evaluation of transportation projects. For each regulation, a summary of its purpose, applicability, general procedures and coordinating agencies is included, as applicable.

In summary, all transportation projects that have federal involvement, through funding and/or permitting, must be evaluated in accordance with the environmental regulations and guidances that have emerged through NEPA. Transportation projects proposed by TDOT that have such federal involvement are consequently subject to NEPA. This manual is intended to assist in the preparation of NEPA documents for those projects.

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1 The United States Code (USC) is the codification by subject matter of general and permanent laws of the United States. It is divided into 50 titles. It does not include regulations issued by the Executive Branch. Electronic access is through

2 The Code of Federal Regulations (CFR) codifies the general and permanent rules for the executive departments and agencies of the Federal Government. These rules are first published in the Federal Register. The CFR is divided into 50 titles that represent broad areas subject to federal regulation. Title 23 relates to the FHWA, and Title 49 relates to the FTA. Electronic access is through

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