(a) A lead agency shall supervise the preparation of an environmental impact statement or a complex environmental assessment if more than one Federal agency either:
(1) Proposes or is involved in the same action; or
(2) Is involved in a group of actions directly related to each other because of their functional interdependence or geographical proximity.
(b) Federal, State, Tribal, or local agencies, including at least one Federal agency, may act as joint lead agencies to prepare an environmental impact statement or environmental assessment (§ 1506.2 of this chapter).
(c) If an action falls within the provisions of paragraph (a) of this section, the potential lead agencies shall determine, by letter or memorandum, which agency will be the lead agency and which will be cooperating agencies. The agencies shall resolve the lead agency question so as not to cause delay. If there is disagreement among the agencies, the following factors (which are listed in order of descending importance) shall determine lead agency designation:
(1) Magnitude of agency's involvement.
(2) Project approval or disapproval authority.
(3) Expertise concerning the action's environmental effects.
(4) Duration of agency's involvement.
(5) Sequence of agency's involvement.
(d) Any Federal agency, or any State, Tribal, or local agency or private person substantially affected by the absence of lead agency designation, may make a written request to the senior agency officials of the potential lead agencies that a lead agency be designated.
(e) If Federal agencies are unable to agree on which agency will be the lead agency or if the procedure described in paragraph (c) of this section has not resulted in a lead agency designation within 45 days, any of the agencies or persons concerned may file a request with the Council asking it to determine which Federal agency shall be the lead agency. A copy of the request shall be transmitted to each potential lead agency. The request shall consist of:
(1) A precise description of the nature and extent of the proposed action; and
(2) A detailed statement of why each potential lead agency should or should not be the lead agency under the criteria specified in paragraph (c) of this section.
(f) Any potential lead agency may file a response within 20 days after a request is filed with the Council. As soon as possible, but not later than 20 days after receiving the request and all responses to it, the Council shall determine which Federal agency will be the lead agency and which other Federal agencies will be cooperating agencies.
(g) To the extent practicable, if a proposal will require action by more than one Federal agency and the lead agency determines that it requires preparation of an environmental impact statement, the lead and cooperating agencies shall evaluate the proposal in a single environmental impact statement and issue a joint record of decision. To the extent practicable, if a proposal will require action by more than one Federal agency and the lead agency determines that it requires preparation of an environmental assessment, the lead and cooperating agencies should evaluate the proposal in a single environmental assessment and, where appropriate, issue a joint finding of no significant impact.
(h) With respect to cooperating agencies, the lead agency shall:
(1) Request the participation of each cooperating agency in the NEPA process at the earliest practicable time.
(2) Use the environmental analysis and proposals of cooperating agencies with jurisdiction by law or special expertise, to the maximum extent practicable.
(3) Meet with a cooperating agency at the latter's request.
(4) Determine the purpose and need, and alternatives in consultation with any cooperating agency.
(i) The lead agency shall develop a schedule, setting milestones for all environmental reviews and authorizations required for implementation of the action, in consultation with any applicant and all joint lead, cooperating, and participating agencies, as soon as practicable.
(j) If the lead agency anticipates that a milestone will be missed, it shall notify appropriate officials at the responsible agencies. As soon as practicable, the responsible agencies shall elevate the issue to the appropriate officials of the responsible agencies for timely resolution.