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Environmental Review Toolkit

NEPA Implementation

Project Development and Documentation Overview

Federal Highway Administration
August 21, 1992

Table of Contents



Early Coordination
Processing Options
- Environmental Impact Statements
- Categorical Exclusions
- Environmental Assessments
Mitigation and Enhancement
Supplemental EIS



A. Legislation:

Federal-Aid Highways, Title 23, United States Code, "Highways," National Environmental Policy Act of 1969, as amended (NEPA), plus numerous other related statutes and orders.

B. Regulations:

"Regulations for Implementing the Procedural Provisions of the National Environmental Policy Act" - 40 CFR Parts 1500-1508, November 29, 1978 (Council on Environmental Quality - CEQ)

"Environmental Impact and Related Procedures" 23 CFR 771, August 28, 1987 (FHWA)

C. Federal Highway Administration (FHWA) Guidance:

"Guidance for Preparing and Processing Environmental and Section 4(f) Documents" - FHWA Technical Advisory T6640.8A, October 30, 1987

D. Other Guidance:

"Questions and Answers about NEPA Regulations," Council on Environmental Quality (CEQ) Memorandum, March 16, 1981

The RED BOOK - "Applying the Section 404 Permit Process to Federal-Aid Highway Projects," FHWA et al, September 1988

(FHWA Environmental Guidebook (primarily an internal document) - An all-inclusive compendium of environmental guidance information which includes the following:

"Section 4(f) Policy Paper," October 5, 1987 as updated June 7, 1989

"Transportation Enhancement Activities," FHWA Memorandum, April 24, 1992

"Cooperating Agencies," FHWA Memorandum, March 19, 1992

"Purpose and Need," FHWA Memorandum, September 18, 1990



The 1960's brought about an increase in awareness and concern for the environment. In response to this, Congress passed and signed into law, the National Environmental Policy Act of 1969 (NEPA). This Act has three major goals that have influenced the Federal Highway Administration (FHWA) and all Federal agencies: (1) it sets national environmental policy; (2) it establishes a basis for environmental impact statements (EISs); and (3) it created the CEQ. NEPA requires that to the extent possible, policies, regulations and laws of the Federal Government be interpreted and administered in accordance with NEPA. It also requires Federal agencies to use an interdisciplinary approach in planning and decisionmaking for actions that impact the environment. (In FHWA, the interdisciplinary expertise is provided with review by the Washington Headquarters and Regional Offices.) Finally, NEPA requires the preparation of an EIS on all major Federal actions significantly affecting the human environment.

NEPA calls for an examination and consideration of impacts of the proposed action on sensitive resources when we are considering a transportation facility. These resources include, but are not limited to, floodplains, wetlands, endangered species, historic and archeological sites, parklands, air quality, wildlife habitat, etc. There also are the transportation needs that need to be fulfilled. Because of impacts to resources and needed transportation improvements, we use a balanced decisionmaking process that considers a range of factors of both impacts to the resources and the transportation needs. The decision of how to balance these factors rests with FHWA.

It is FHWA's policy that all environmental protection and enhancement requirements, including those set out in Section 4(f) of the Department of Transportation (DOT) Act which protects historic sites and publicly owned public parks, recreation areas, wildlife and waterfowl refuges, and 23 U.S.C. 109(h), which mandates consideration of social and economic impacts to the human environment, be completed as part of the NEPA process. Evidence of this compliance must be contained in the appropriate documentation. Further, it is FHWA policy that public involvement be an essential part of this process.

As noted above, NEPA called for the creation of the Council on Environmental Quality (CEQ). The CEQ is an office within the Executive Office of the President and has four main functions: (1) to develop environmental policies for the nation; (2) to monitor environmental quality; (3) to prepare an annual environmental quality report; and (4) to monitor Federal actions.

In 1970, CEQ issued guidelines for the preparation of environmental documents. The FHWA prepared a policy directive in response to those guidelines as did some other Federal agencies. For FHWA this regulation is "Environmental Impact and Related Procedures," 23 CFR 771, effective November 28, 1987. The CEQ monitored Federal environmental processing of all the agencies, and found that EISs were too long with less important issues being discussed at great length, that there ' was poor or no early coordination, and that the process led to unnecessary delays caused by confusion over differing terminology and procedures among Federal agencies. To remedy these problems, President Carter issued Executive Order (EO) 11991 in May 1977. The key provision of the EO was that CEQ could issue mandatory regulations, not just guidelines, for implementing the provisions of NEPA consistently throughout the Federal Government. The result was the CEQ Regulations for Implementing the Provisions of the National Environmental Policy Act," 40 CFR Parts 1500-1508.

The principal goals of the CEQ regulations are to reduce paperwork and delays, and to produce better environmental decisions. The regulations focus on four key areas: (1) early coordination; (2) completing the environmental process; (3) uniform processing options for all agencies; and (4) faster and better processing.

To improve early coordination, the CEQ regulations introduced the concept of "lead agency" and "cooperating agency." The lead agency is that Federal agency which is responsible for the Federal action. The cooperating agencies are those with special expertise (e.g., the Fish and Wildlife Service, the Department of the Interior) or jurisdiction by law (e.g., the Army Corps of Engineers (COE) or the Coast Guard (USCG) when a permit is necessary). The CEQ also instituted a scoping process which was intended to get the lead and cooperating agencies and other interested groups together early in the project development process to determine the scope of the issues to be addressed, and identify any important issues related to the proposed action. By properly using the early coordination process, agencies could avoid conflicts later, and could assure the full input from the various interests. Early coordination continues to be emphasized in all transportation guidance and legislation.

In order to aid in completing the process, CEQ introduced two specific formal decision documents: (1) the Finding of No Significant Impact (FONSI) and (2) the Record of Decision (ROD). These will be discussed in more detail later, but use of these reflects CEQ's belief that the environmental document should be a full-disclosure information document but that there still was a need for a formal decision document.

The CEQ regulations also established uniform processing options for all Federal agencies. These options are the categorical exclusion (CE), the EIS, and the environmental assessment (EA).

One key early decision for FHWA is the type of document needed to satisfy the NEPA process and thus advance a project. Remember, NEPA requires an EIS for major Federal actions significantly affecting the human environment, and 23 U.S.C. 109(h) requires consideration of adverse economic and social (as well as environmental) impacts for Federal-aid highway projects. The key here is "significance," and guidelines for determining significance will be described later. For now it is important to understand that projects with clearly identified, significant social, economic, or environmental impacts always require an EIS.

A second type of project also emerges--those without significant impacts. These CE projects, under certain circumstances, can be "categorically excluded" from having an EIS prepared. A third grouping is those projects with uncertainty as to whether there is a significant impact. In those cases, EAs are prepared to determine if there will or will not be significant impacts associated with a project. If there are no significant impacts, a Finding of No Significant Impact (FONSI) is prepared. If the EA indicates there are significant impacts, an EIS must be prepared.

Early Coordination

Early coordination with other agencies and the public is an essential part of the project development process. This coordination can help you in determining the appropriate level of documentation and developing the project purpose and need discussion, as well as in identifying the NEPA and permit requirements of other agencies, the range of alternatives, impacts to resources, possible mitigation measures, and opportunities for environmental enhancement. When you begin early coordination, be aware of three items: (1) cooperating agencies, (2) the memorandum of understanding-with the USCG, and (3) the memorandum of agreement with the COE. The agreements with the USCG and COE were developed because of the large number of permits required from these agencies. A Section 404 permit from the COE is required for any dredge/fill operation in waters of the United States including jurisdictional wetlands, and the USCG requires permits for crossings of navigable waters. The central feature of these agreements is that, if we get the COE and USCG involved in the process early, they can adopt FHWA's NEPA documentation to fulfill the NEPA requirements for their permit action. As one approach towards improving interagency coordination, the Red Book emphasizes the merging of the common elements of the NEPA and Section 404 permit processes. The Red Book has been adopted as policy by the DOT, EPA, and COE.

The lead agency/cooperating agency concept was introduced by CEQ to aid in early coordination and faster and better processing. A lead agency is responsible for supervising the preparation of the environmental documentation. Cooperating agencies are those agencies specifically requested by the lead agency to assist during the environmental process. CEQ's regulations require that those Federal agencies with jurisdiction by law be requested to be cooperating agencies for EAs and EISs. Examples include the COE where Section 404 permits are involved, the USCG where a Section 9 permit is involved, the EPA for sole-source aquifers, and other Federal agencies where a land transfer from that agency is needed. Also included as potential cooperating agencies would be any other Federal agency with special expertise, any State agency, local agency, or Indian tribe when Indian reservation land is involved.

Cooperating agencies should be requested as early in the process as possible. The point here is to get these agencies involved so they have real input early rather than later where they are merely reacting to our proposals. Either the State or FHWA can request cooperating agencies.

If an agency with jurisdiction by law declines a request to be a cooperating agency, notify FHWA Headquarters, so that we can assist in resolving the problem.

A cooperating agency does not necessarily need to perform any analysis or provide any substantive narrative for the document, but the expectations and responsibilities of a cooperating agency should be clearly understood. When a cooperating agency has jurisdiction by law, that agency's role should be acknowledged in the environmental documentation. A cooperating agency, while not necessarily agreeing with every word in the document, should be in a position (at the end of the process) to state that the final document fulfills its responsibilities under NEPA.


To determine the appropriate class of action and thereby the requisite level of documentation necessary to comply with NEPA, it is essential to understand the term "significance." The CEQ regulations (40 CFR 1508.27) state that two main points should be considered in determining significance: context and intensity.

Impacts can be considered in the context of society as a whole, the affected region, or locality. In the case of a site-specific action, significance would usually depend on the effects in the locale rather than in the world as a whole. Both short- and long-term effects are relevant.

For example, filling one acre of a one hundred-acre wetland probably could be considered not significant, but filling one acre of a two-acre wetland may be considered, under certain circumstances, a significant impact. The intensity is the same, but the context is different.

Factors to consider regarding intensity or severity of impacts include: (1) impacts that may be both beneficial and adverse; (2) the degree to which the proposed action affects public health or safety; (3) unique characteristics of the geographical area; (4) the degree to which the effects on the quality of the human environment are likely to be highly controversial; (5) the degree to which the possible effects on the human environment are highly uncertain or involve unique or unknown risks; (6) the degree to which the action may establish a precedent for future actions with significant effects; (7) whether the action is related to other actions with individually insignificant but cumulatively significant impacts; and (8) the degree to which the action may adversely affect resources listed in or eligible for listing in the National Register of Historic Places; (9) the degree to which the action may adversely affect an endangered or threatened species or its habitat; and (10) whether the action threatens a violation of Federal, State, or local law or requirements imposed for the protection of the environment.

Processing Options

Environmental Impact Statement

When the proposed action will have a significant impact on the environment, an EIS is required. Less than 5 percent of all FHWA projects involve EISs, but these are the projects which require the most time and effort to complete.

As soon as a decision has been reached to prepare an EIS, the FHWA division office should prepare a Notice of Intent. Guidelines for preparation of these notices are given in Technical Advisory T6640.8A. This notice which is published in the Federal Register is a brief announcement that FHWA will be preparing an EIS.

Scoping is a formal coordination process, required by CEQ, which determines the scope of issues to be addressed and identifies the significant issues related to the proposed action. It can be done by letter, phone or formal meeting. You should assure that it occurs early and involves both affected agencies and interested public, and is well-documented. The scoping and Notice of Intent requirements reflect CEQ's concern for early coordination and faster and better processing.

Technical Advisory T6640.8A provides guidance on what should be in the EIS. It provides the required format and the type of information that should be developed in the EIS. A brief summary of the major EIS sections follows:

Project Purpose and Need is one of the most important elements of project and needs to be well-documented in the EIS. This discussion should be clear and specific, and support the need for the project. For example, if there is a capacity problem, it should be stated in this section and referenced in later traffic discussions, not the other way around. Some of the common "needs" we see in ElSs include: transportation demand, safety, legislative direction, urban transportation plan consistency, modal interrelationships, system linkage, and the condition of existing facility. Graphics and tables are particularly helpful in clarifying the discussion.

The Alternatives section describes the reasonable alternatives to achieve the project's purpose and need, how they were selected, and provides a clear basis for choice among the options. In developing your alternatives, you must comply with the requirements of 23 CFR 771.111(f), which states that projects must connect logical termini, have independent utility, and not restrict consideration of future transportation alternatives. Also, you may have examined some alternatives early in the process but found them to be not reasonable for further consideration. The Alternatives section should briefly explain why these alternatives were rejected from further study.

In the draft EIS stage, all reasonable alternatives should be discussed at a comparable level of detail. There is no requirement at this stage to have a "preferred" alternative; however, if an official position has been taken on one of the alternatives, this should be so stated in the document. Of course, at this stage in the process, no final decision can be made.

The "no-build" alternative must always be included. In addition to fulfilling a requirement, discussion of this alternative can serve two purposes. First, it may be a reasonable alternative, especially where the impacts are high and the need is relatively minor. More often, the no-build serves as a benchmark against which the impacts of the other alternatives can be compared. As part of this alternative, short-term minor reconstruction, such as safety upgrading and maintenance projects, can be considered.

Transportation System Management must be included as an alternative or design option where applicable. This can include high-occupancy vehicle lanes, ridesharing, signal synchronization, and other actions. Also, where appropriate, mass transit options should be considered.

Graphics, should show the location of the alternatives in relation to each other and the project area. Alternative termini points and design features, such as the number of lanes and location of interchanges, should also be shown.

The Affected Environment section is one area in EISs where there has been a tendency to include too much information. These documents are for decision purposes and, as such, descriptions should be no longer than needed to understand the area and the impacts of the alternatives. The affected environment section should discuss, commensurate with the importance of the impact, the existing social, economic, and environmental setting. Also, it should identify environmentally sensitive features. The use of graphics and/or photographs for this purpose is especially effective.

The Environmental Consequences section describes the impacts of the alternatives to the affected environment and documents the methodologies used in the evaluation. This information will be used to form a basis for the comparison of alternatives. One problem we have seen in this section is the use of generic statements like, "all highway construction in this area will cause erosion which adds to sediment loading in streams." That may be true enough, but it does not help differentiate between the alternatives or show the relative severity of the alternatives. For example, does one alternative cross more streams than another? Are some streams more sensitive? Also, is this erosion severe or minor and how do we quantify the impact? Here again, you should consider context and intensity. This section of the document should discuss both impacts and mitigation measures. It should be remembered that mitigation must be considered for all impacts, regardless of significance. Additional consideration should be given to using enhancement measures to help better fit the project into the environment.

A second area for consideration is that of secondary and cumulative impacts. Secondary impacts are those effects that are expected to be "caused" by the proposed action but are later in time or are removed in distance, but are still reasonably foreseeable. Cumulative impacts are those which result form the incremental consequences of an action when added to other past and reasonably foreseeable future actions.

The EIS also has a Comments and Coordination section where the scoping process, including the results of any meetings which may have been held and any comments received during preliminary coordination, should be summarized.

Another section, the List of Preparers, includes those primarily responsible for preparing the EIS or background papers. This includes SHA personnel involved and may include other State offices, consultants, and local people. The FHWA division office representative should also be included. This list should include the individual's name and qualifications including his/her expertise, experience, and professional discipline.

Between the draft and final EIS, the SHA and FHWA division office consider and prepare responses to all substantive comments received on the draft EIS, including those from the public hearing. The final EIS must identify and describe the preferred alternative and the basis for the decision, demonstrate compliance to the extent possible with all applicable environmental laws and Executive Orders, provide reasonable assurance that the requirements can be met, include copies of comments received and responses (if comments are voluminous they may be summarized), note where the EIS was changed in response to comments, (this change should be referenced in the response), and any other changes or corrections.

The final EIS is usually approved at the Regional Office level; however, prior concurrence by the Washington Headquarters Office is required on certain types of projects and under certain conditions (see 23 CFR 771.125(c)).

A ROD must be issued before any project approvals (e.g. for design, right-of way acquisition, construction) can be given on the selected course of action. The ROD may not be issued sooner than 30 days after the approved final EIS is distributed, nor 90 days after the Draft EIS is circulated. It should: (1) state the basis for the decision, (2) identify all the alternatives considered and specify the "environmentally preferable alternative," (a thorough discussion of the "environmentally preferred alternative" can be found in CEQ's "Questions and Answers about the NEPA Regulations," Question #6), and (3) state whether all practicable means to avoid or minimize environmental harm from the alternative selected have been adopted and, if not, why they were not.

Categorical Exclusions

Actions that do not individually or cumulatively have a significant social, economic, or environmental effect are excluded from the requirement to prepare an EA or EIS. These actions are processed as CEs. A specific list of CEs normally not requiring NEPA documentation is set forth in 23 CFR 771.117(c). Other projects, pursuant to 23 CFR 771.117(d), may also qualify as CEs if appropriately documented. There are various approaches to documenting CE determinations where required. For minor activities, programmatic approaches can reduce the amount of paper generated while still assuring adequate program control. More complex projects require more information in a formal submission from the State so that the FHWA division office can conclude that the project will not cause a significant environmental impact.

Environmental Assessment

An EA is prepared when there is uncertainty as to the significance of the impacts of the project.

The CEQ suggests that EAs should be only 10 to 15 pages in length. It is often not possible to stay within these page limits, especially if information related compliance with other environmental requirements is included. It is, however, instructive to understand CEQ's philosophy on the brevity of the EA. It should discuss in detail only those areas where there is potential for a significant impact. Although there is no specific format requirement, the FHWA Technical Advisory 6640.8A provides a suggested format to be used for an EA. Briefly, the subject areas to be addressed are: project description, need, alternatives considered, impacts, and comments and coordination.

The EA is subject to FHWA approval before it is made available to the public as an FHWA document. The document itself need not be circulated, but must be made available for public inspection and comment. A notice of availability must be sent to State and area wide clearinghouses and should be published locally. Depending on FHWA-approved State procedures, a public hearing may or may not be required. The availability period for an EA is usually 30 days.

If, after completing the process, it is determined that there are no significant impacts associated with the project, a FONSI (the agency's statement of no significant impact) is prepared. The FONSI includes the EA modified to reflect all applicable comments and responses to those comments. No formal circulation is required, however, the State clearinghouse must be notified of the availability of the FONSI, and FHWA recommends that the public be notified in local publications. A sample of the language used for a FONSI can be found in Technical Advisory T6640.8A (page 9).

If, at any time, a significant impact is identified, an EIS must be prepared.

Mitigation and Enhancement

It has been FHWA's policy that measures necessary to mitigate adverse impacts (both significant and non-significant) be incorporated into the proposed action (23 CFR 771.105(d)). The CEQ regulations describe (40 CFR 1508.20) some of the methods for mitigating impacts. They include: avoidance, minimizing impacts by limiting the scope of the action, rehabilitating or restoring the affected environment, and compensating for the impact by replacing or providing substitute resources. Such measures would be eligible for Federal funding if: (1) the impact for which the mitigation was proposed actually resulted from the project and (2) the proposed mitigation represented a reasonable public expenditure, considering, among other things, the extent to which the proposed measures would assist in complying with a Federal statute, Executive Order, or other Administration regulation or policy.

The Environmental Policy Statement (the EPS was first issued in 1990 and revised in 1994) called for an expanded interpretation of these requirements, and specifically itemized full and objective consideration to avoidance, innovative designs to minimize harm, and identification of opportunities to contribute to a healthier, more attractive environment through improved mitigation and enhancement. The only restrictions that the EPS placed on funding environmental enhancement activities were that such activities represent a reasonable public expenditure, be in the best overall public interest, and be reasonable related to an eligible highway project. (Please note that the environmental enhancement described in the EPS should not be confused with the "transportation enhancement" provision in the ISTEA legislation, which is a 10% funding set-aside for ten specific types of enhancement activities. That program should be considered as one element of our overall enhancement policy.)

It is the responsibility of FHWA and the implementing agency to assure that the mitigation and enhancement measures committed to in the environmental document, as well as those contained in permits, are carried out. We encourage that a summary of mitigation/enhancement commitments be included in the FONSI or ROD and made available to appropriate project personnel.


The FHWA must assure that the environmental documentation for the proposed action (CE, EA/FONSI, EIS/ROD) is still valid, prior to proceeding with major project approvals or authorizations. This is accomplished through a reevaluation, which is an assessment of any changes which may have occurred in either the project's concept or the affected environment, and a determination of what effects these changes might have on the validity of the environmental documentation. Informal consultation between FHWA and the State DOT may be acceptable, with appropriate documentation (e.g. a note to the file).

In addition to this requirement for all levels of environmental documentation, there is a 3- year validity period for EISs. If you have a Draft EIS, and an acceptable Final EIS is not submitted to FHWA within 3 years from the date of the draft EIS circulation, a written reevaluation of the Draft EIS shall be prepared prior to submission of the Final EIS. This evaluation must demonstrate that the information presented in the Draft EIS is an accurate analysis of the anticipated project impacts. For projects with an approved Final EIS, a written reevaluation is required before further approvals are given if activities to advance the action, e.g., design, right-of-way, or construction, have not occurred within any 3-year time period.

Supplemental EIS

If the reevaluation process described above reveals that there have been changes which result in significant adverse impacts not identified in the approved document, a new EIS or a Supplemental EIS (SEIS) must be prepared and circulated.

If changes are made to the proposed actions and it is uncertain if a Supplemental EIS is required, appropriate environmental studies or, if necessary, an EA to assess the impacts of such changes must be developed.

There is no required format for a SEIS, but it must contain the reason for preparing a Supplement and an evaluation of the changes and new impacts. Portions of the original EIS which remain valid may be summarized. The SEIS is processed in the same way as the original document, except that there is no requirement for formal scoping.


Q. How should a project that is on the CE list (23 CFR 771.117(d)), but has a significant impact, be processed?

A. Any project that has a significant impact must be processed as an EIS.

Q. If an EA indicates that there will be a significant impact but that, with mitigation, the impact may be reduced to less than significant levels, can a FONSI be made rather than preparing an EIS?

A. Mitigation measures may be relied upon to make a FONSI as long as a commitment is made to provide all mitigation needed to reduce impacts below the level of significance, and the mitigation is made an integral part of the original proposal.

Q. In preparing an EA, it became obvious that there was a significant impact. Should we go ahead with the EA before preparing a draft EIS?

A. No. As soon as it has been determined that there is a significant impact, a Notice of Intent should be prepared and the development of the draft EIS should begin. Practically speaking, very few projects go from an EA to a draft EIS, but rather the determination that there is a significant impact occurs while the EA is being developed.

Q. A certain project requires a Section 404 permit (or Section 9 USCG permit). Should we request that the COE (or CG) be a cooperating agency?

A. Permitting agencies such as the COE (or USCG) which have jurisdiction by law must be requested to-be a cooperating agency for projects requiring an EIS. It is desirable for them to be a cooperating agency for EA/FONSI projects. For CE projects, early coordination should occur.

Q. What do you do when an agency with jurisdiction by law refuses a request to be a cooperating agency for and EIS/ROD project?

A. Notify the Washington Headquarters (HEP-30) through normal channels. The CEQ regulations require that CEQ be notified of such a refusal.

Q. During the circulation of a draft EIS, someone suggested that a totally new alternative be studied. How should such a comment be handled?

A. As with all comments on a draft EIS, it must be considered and addressed. If the alternative is not considered reasonable, a response discussing the rationale for that determination should be included in the final EIS. If the alternative is reasonable and totally new, not just a design variation of one presented in the draft EIS, then a supplemental draft EIS discussing the alternative must be prepared and circulated. The CEQ regulations (40 CFR 1502.14(a)) require that the EIS "rigorously explore and objectively evaluate all reasonable alternatives." See CEQ's "Questions and Answers About NEPA Regulations," Question #29, for further information.

Q. The FHWA was a cooperating agency on an EIS prepared by another agency. The approved final EIS adequately discusses all aspects of the project including some highway work. Must FHWA do an EA or EIS to comply with NEPA in this case?

A. One advantage of the cooperating agency concept is that the cooperating agency may adopt another agency's environmental document to comply with NEPA. In this case, a ROD should be prepared to document the basis for decision. The FHWA need not recirculate the EIS. In the case of adopting another agency's EA, a FONSI should be prepared to document the basis for the decision.

Q. What is the advantage of getting the COE and/or the CG as a cooperating agency when a permit is required?

A. As noted above, those agencies with jurisdiction by law (i.e., permitting agencies) must be requested to be cooperating agencies. The FHWA has agreements with these agencies which state that if we coordinate with these agencies early and include in our environmental document the information they need for permit processing, these agencies will ordinarily accept our environmental documentation as satisfying NEPA for processing the permit. In addition, we have an ongoing initiative to "merge" the common elements of the NEPA and 404 processes. This is outlined in Chapter 11 of the "Red Book."

Q. The State has decided that it wants to implement an alternative which was adequately evaluated and presented in the approved final EIS, but was not identified as the preferred alternative. Must we prepare a new final EIS?

A. No. The ROD is the decision document and, as such, can be used to describe why this alternative has now been selected for implementation.

Q. What material should be in an appendix rather than the body of the EIS?

A. The body of the EIS should be a succinct statement of all the information the decision maker and public need to make the decision. The EIS must explain or summarize methodologies of analysis and the conclusions of those analyses. Lengthy technical discussions of modeling methodology, baseline studies, or other technical work should go into the appendix.

Q. How should comments on a draft EIS be handled, especially if the project generated voluminous comments?

A. The final EIS must contain responses to all substantive comments on the draft EIS. These responses may result in changes in the document, but specific answers to each significant comment should also be included. These specific responses may be placed in an appendix. If the comments are especially voluminous, summaries of the comments and responses will suffice.