Environmental Impact Statement (EIS) Format and Content Process

Most of the information and analysis developed through the Environmental Impact Statement (EIS) process is presented in a single document. The actual organization of the EIS varies from project-to-project and from Region-to-Region. Some key components of the EIS are described below:


The summary presents an overview of the contents of the EIS and a comparison of impacts expected for the proposal and alternatives.

Purpose and Need

This section explains the purpose and need for the proposal and our authority for taking action on the proposal. The section may also describe the relationships between our authority to consider the proposal and the other legal and regulatory authorities that apply to the activities that might result. We include a summary of the scoping process here (or in the section on consultation and coordination below) that identifies the concerns, alternatives, and mitigation measures that are considered in detail in subsequent sections of the EIS.

Proposed Action and Alternatives

Scenarios are presented that describe the activities assumed for the proposal and each alternative. The description details any mitigation measures, such as lease stipulations for lease sale EISs, that are being considered for adoption. This section also summarizes the impacts expected to result from the proposal and each alternative, including no action.

Affected Environment

This section describes the elements of the natural, social, and economic environments that might be affected by the proposal or the alternatives. Emphasis is placed on the current status of each element and any trends that may be evident. For example, a potentially affected bird might be described in terms of its population, distribution, habits, and current condition.  This section provides a baseline against which changes that might be caused by the proposal can be measured.

Expected Impacts

This section presents our assessment of the impacts that might be expected if the activities presented in the scenarios occur. A separate analysis is presented for the proposal and each alternative. Direct, indirect, and cumulative impacts are evaluated. Each analysis describes the nature, severity, and duration of estimated impacts. If the project could result in oil spills, the EIS also describes the risk of spills occurring or contacting particular resources. A conclusion about predicted impacts is also presented for each concern analyzed.

Consultation and Coordination

This section documents how we consulted with government, public, and individual interests during preparation of the EIS. The principal emphasis of this section is a summary of the public comments that we received on the draft EIS and our responses to those comments. Other types of information included in this section are:

  • Results of any consultation with the appropriate Federal Agencies about the possible impacts of the proposal on endangered or threatened plant or animal species.
  • Descriptions of the public participation process, including the details of scoping meetings and public hearings.
  • Listings of the persons or groups that were provided copies of the EIS.

We have established formal agreements with the US Environmental Protection Agency (EPA) to cooperate in preparing some EISs. The EPA normally prepares or assists with the water quality analysis and air quality analysis because they regulate air emissions and discharges into marine waters from OCS operations. We may also be a cooperating agency on an EIS prepared by another Federal Agency, such as the Army Corps of Engineers, for proposed oil and gas activities.

During development of the EIS, we also consult with the U.S. Fish and Wildlife Service and the National Marine Fisheries Service about the potential effects of oil and gas activities on species protected under the Endangered Species Act.


This section contains a variety of technical reports that support the analysis of expected impacts. Normally included among those reports are: our assessment of amounts of oil and gas resources that might be discovered in and produced from the area covered by the proposal (program and leasing EISs); our assessment of the probabilities that oil spills might occur and the possible movements of spilled oil; and a description of equipment and procedures that would be used to respond to an oil spill.