reimburse the Administrator in the amount that is the difference between the open market value of the motor vehicle and the amount that the operator paid to the Administrator for the motor vehicle. (D) The operator shall donate not less than one out of every five of such motor vehicles to a local nonprofit organization after the motor vehicle is no longer used to provide ground transportation service. (2) Maximum number of vehicles that may be purchased annually An operator may not purchase through the program established under subsection (a) more than 50 vehicles in any fiscal year. (e) Exemption from certain property disposal requirements The program established under subsection (a) shall not be subject to— (1) subchapter IV of chapter 5, title 40, United States Code