(a) In most cases, the Responsible Official should designate one Federal agency as the lead with the remaining Federal, State, Tribal, and local agencies assuming the role of cooperating agency. In this manner, the other Federal, State, Tribal, and local agencies can work to ensure that the environmental impact statement will meet their needs for adoption and application to any related decision.

(b) In some cases, a non-Federal agency (including a State, Tribal, or local government) must comply with State, Tribal, or local requirements that are comparable to the NEPA requirements. In these cases, the Responsible Official may designate the non-Federal agency as a joint lead agency.

(c) In some cases, the Responsible Official may establish a joint lead relationship among several Federal agencies. If there are joint leads for an environmental impact statement, then one Federal agency must be identified as the agency responsible for filing the environmental impact statement with the Environmental Protection Agency.

(d) Bureaus may allow joint lead agencies to cooperate in developing environmental assessments.