5 U.S.C. § 583

For the purposes of this subchapter, an agency may use (with or without reimbursement) the services and facilities of other Federal agencies, State, local, and tribal governments, public and private organizations and agencies, and individuals, with the consent of such agencies, organizations, and individuals. An agency may accept voluntary and uncompensated services for purposes of this subchapter without regard to the provisions of section 1342 of title 31.