An EA is described in 40 CFR 1508.9 of the Council on Environmental Quality's NEPA regulations. Generally, an EA includes brief discussions of the following:
- The need for the proposal;
- Alternatives (when there is an unresolved conflict concerning alternative uses of available resources);
- The environmental impacts of the proposed action and alternatives; and
- A listing of agencies and persons consulted.
An EIS, described in 40 CFR Part 1502 of the NEPA regulations, includes discussions of the following:
- The purpose of and need for the action;
- Affected environment;
- Environmental consequences of the proposed action;
- Lists of preparers;
- List of agencies, organizations and persons to whom the statement is sent;
- An index, and
- An appendix (if any).