No, while Self-Governance Tribes are required to assume Federal environmental responsibilities for projects in place of the Secretary, Self-Governance Tribes do not thereby become Federal agencies. However, because Self-Governance Tribes are assuming the responsibilities of the Secretary for the purposes of performing these Federal environmental responsibilities, Self-Governance Tribes will be considered the equivalent of Federal agencies for certain purposes as set forth in this subpart.
42 C.F.R. § 137.286