Best Practices for Environmental Impact Statement (EIS) Management

July 2001 (Updated January 2002)


Managing the Scope and Size of Environmental Documents

From the very beginning of compliance with the National Environmental Policy Act (NEPA), there has been a conflict between the need to prepare legally sufficient Environmental Impact Statements and Environmental Assessments and the need to manage the size of these documents. The regulations promulgated by the Council on Environmental Quality (CEQ) in 1978 established a target size for EIS's as "normally not to exceed 150 pages in length and for proposals of unusual scope or complexity 300 pages" (40 CFR 1502.7). In 1981, as a part of additional guidance (Forty Most Asked Questions Concerning CEQ's National Environmental Policy Act Regulations), CEQ issued an opinion that Environmental Assessments should not exceed 10-15 pages in length. Even a casual review of documents recently approved by FAA would indicate that these policies are honored more in their breach than in their compliance.

The Problem. Susan Smillie and Lucinda Swartz identified three reasons Federal agencies fail to meet or even approach the page limits established by CEQ in a paper presented to the convention of the National Association of Environmental Professionals in May 1997 . These reasons are (1.) A requirement by counsel to "beef up" EIS's in the hope that volume will deter potential litigants or in the event the deterrence fails that the agency can argue "it's in there somewhere;" (2.) Failure to properly scope the document; and (3.) In the case of EA's, preparation of "mini-EIS's" rather than an appropriate assessment. It appears that, in addition, in those states where joint Federal/state environmental documents are prepared such as in California, the state requirements frequently appear to add extensive volume to the Federal documents.

Some Proposed Solutions. Several potential techniques for reducing the size of NEPA documents are included below. You should always keep in mind that in attempting to reach a particular size goal, you cannot sacrifice the "hard look" that is required by NEPA.

Scoping. When preparing an EIS, the scoping process provides the first and generally one of the best opportunities to keep the document from excessive growth later. A proper analysis of the scope of the project will allow limitations on what has to be analyzed later. It is particularly important at this stage to understand the nature of the decision that is to be supported by the contents of the environmental document.

Tiering. Tiering is a concept supported by the CEQ Regulations (40 CFR 1508.28), which provides a process for analysis of broad conceptual proposals followed by narrower site-specific analyses incorporating the earlier work by reference. Tiering has limited utility in most airport projects, but it may prove useful in some circumstances, in particular in the case of siting proposed new airports.

Incorporation by Reference. Documents not directly used in an EIS should be incorporated by reference. If this is done, care should be taken that documents referenced are reasonably available to any reviewer who wants to review them.

EIS Documents

  • Purpose and Need: A well-written statement of the purpose and need for the project (not why a document was prepared) lays the groundwork for a well-written, disciplined EIS document.
  • Alternatives Including the Proposed Action: It is frequently possible to reduce the size of EIS's by taking special care in describing the alternatives in this section. Since it is normally the practice to compare the impacts of the various alternatives in detail in the environmental consequences section, detailed comparisons of impacts may be avoided here. One suggestion used recently in a DEIS -- a summary table comparing the proposed project and its alternatives in this section, referring to the detailed discussions in the subsequent environmental consequences section.
  • Affected Environment: Because significant amounts of data are generally available on current conditions, there is a tendency to "load up" an EIS with such data simply because it is there. One method that seems to help is to limit the affected environment description to a relatively minor discussion of where the proposed project is located and general conditions in the area, and to include specific detailed information in theEnvironmental Consequences section which follows. In doing this, you should take care not to simply transfer the problem from one chapter to another.

For EA's you should consider combining the affected environment and environmental consequences section, which will eliminate the tendency to duplicate material.

  • Environmental Consequences: This section should focus on significant impacts. If a project or any of its alternatives has little or no impact in a certain impact category, that should be clearly stated and not repeated over and over. It may be useful to duplicate applicable portions of the comparative table discussed under alternatives above so as to provide a graphic comparison of the project and its alternatives under specific impact topics.
  • Appendices: You should take care to include as appendices all of the information necessary for a reasonable review of the document, but not to include data for data's sake. If it appears that appendices are growing beyond a reasonable size, you should consider reducing them to electronic format and making them available either on-line or in the form of a compact disk.

Environmental Assessments. The three purposes of an EA as outlined in CEQ's Forty Most Asked Questions are: (1.) Briefly provide sufficient evidence and analysis to determine whether to prepare an EIS; (2.) Aid an agency's compliance with NEPA when no EIS is necessary (i.e. it identifies alternatives and mitigation); and (3.) Facilitate preparation of an EIS when one is necessary. Since the EA is intended to be a concise document, it should not contain long descriptions or detailed data that the agency may have gathered. Rather, it should contain a brief discussion of the need for the proposal, alternatives to the proposal, environmental impact of the proposal and alternatives, and a list of persons and agencies consulted (see 40 CFR 1508.9 (b)). There are circumstances in which a voluminous EA is needed, but these should be exception rather than the rule.

EA vs. EIS. When a proposed action at first blush appears to be on the borderline of significant impacts, it is always possible to proceed with a Draft EIS and subsequently to convert the document to a FONSI if impacts are shown not to be significant upon further investigation and/or mitigation. The advantage to this approach is that time can be saved by avoiding a two-step EA-EIS process if an EIS proves to be required. The immediate initiation of an EIS assures that the contractor selection and scoping conform to EIS requirements. The Notice to Prepare an EIS should alert agencies and the public that environmental impacts may be shown not to be significant, in which case the document would be concluded as a FONSI. The decision to complete the document as either an EIS or FONSI would normally be made after agency and public review and comment on the Draft EIS. The decision to pursue this type of approach to an environmental document involves discretionary judgment by FAA. There is no mandated requirement.

Last updated: Tuesday, August 2, 2022