18 CFR 380.2 - Definitions and terminology.
For purposes of this part -
(a) Categorical exclusion means a category of actions described in § 380.4, which do not individually or cumulatively have a significant effect on the human environment and which the Commission has found to have no such effect and for which, therefore, neither an environmental assessment nor an environmental impact statement is required. The Commission may decide to prepare environmental assessments for the reasons stated in § 380.4(b).
(b) Commission means the Federal Energy Regulatory Commission.
(c) Council means the Council on Environmental Quality.
(d) Environmental assessment means a concise public document for which the Commission is responsible that serves to:
(1) Briefly provide sufficient evidence and analysis for determining whether to prepare an environmental impact statement or a finding of no significant impact.
(2) Aid the Commission's compliance with NEPA when no environmental impact statement is necessary.
(3) Facilitate preparation of a statement when one is necessary. Environmental assessments must include brief discussions of the need for the proposal, of alternatives as required by section 102(2)(E) of NEPA, of the environmental impacts of the proposed action and alternatives, and a listing of agencies and persons consulted.
(e) Environmental impact statement (EIS) means a detailed written statement as required by section 102(2)(C) of NEPA. DEIS means a draft EIS and FEIS means a final EIS.
(f) Environmental report or ER means that part of an application submitted to the Commission by an applicant for authorization of a proposed action which includes information concerning the environment, the applicant's analysis of the environmental impact of the action, or alternatives to the action required by this or other applicable statutes or regulations.
(g) Finding of no significant impact (FONSI) means a document by the Commission briefly presenting the reason why an action, not otherwise excluded by § 380.4, will not have a significant effect on the human environment and for which an environmental impact statement therefore will not be prepared. It must include the environmental assessment or a summary of it and must note other environmental documents related to it. If the assessment is included, the FONSI need not repeat any of the discussion in the assessment but may incorporate it by reference.