(a) The environmental impact statement shall succinctly describe the environment of the area(s) to be affected by the alternatives under consideration, including the reasonably foreseeable environmental trends and planned actions in the area(s).

(b) Agencies shall use high-quality information, including reliable data and resources, models, and Indigenous Knowledge, to describe reasonably foreseeable environmental trends, including anticipated climate-related changes to the environment, and when such information is incomplete or unavailable, provide relevant information consistent with § 1502.21. This description of the affected environment, including existing environmental conditions, reasonably foreseeable trends, and planned actions in the area, should inform the agency's analysis of environmental consequences and mitigation measures (§ 1502.16).

(c) The environmental impact statement may combine the description of the affected environment with evaluation of the environmental consequences (§ 1502.16). The description should be no longer than necessary to understand the relevant affected environment and the effects of the alternatives. Data and analyses in a statement shall be commensurate with the importance of the effect, with less important material summarized, consolidated, or simply referenced. Agencies shall avoid useless bulk in statements and shall concentrate effort and attention on important issues. Verbose descriptions of the affected environment are themselves no measure of the adequacy of an environmental impact statement.