31 U.S.C. § 9701

(a) It is the sense of Congress that each service or thing of value provided by an agency (except a mixed-ownership Government corporation) to a person (except a person on official business of the United States Government) is to be self-sustaining to the extent possible. (b) The head of each agency (except a mixed-ownership Government corporation) may prescribe regulations establishing the charge for a service or thing of value provided by the agency. Regulations prescribed by the heads of executive agencies are subject to policies prescribed by the President and shall be as uniform as practicable. Each charge shall be— (1) fair; and (2) based on— (A) the costs to the Government; (B) the value of the service or thing to the recipient; (C) public policy or interest served; and (D) other relevant facts. (c) This section does not affect a law of the United States— (1) prohibiting the determination and collection of charges and the disposition of those charges; and (2) prescribing bases for determining charges, but a charge may be redetermined under this section consistent with the prescribed bases.