Any official designated by the President to carry out this chapter may procure the temporary or intermittent services of experts and consultants in accordance with the provisions of section 3109 of title 5. Persons so employed shall receive compensation at a rate not in excess of the maximum amount payable under such section. While away from his home or regular place of business and engaged in the performance of services in conjunction with the provisions of this chapter, any such person may be allowed travel expenses, including per diem in lieu of subsistence, as authorized by section 5703(b)  of title 5 for persons in the Government service employed intermittently.
22 U.S. Code § 3106. Use of experts and administrative support services
(a) Compensation and travel expenses
(b) Use of available Federal agency services, equipment, personnel, and facilities