49 CFR § 190.409 - Fee structure.
The fee charged is based on the direct costs that PHMSA incurs in conducting the facility design safety review (including construction review and inspections), and will be based only on costs necessary for conducting the facility design safety review. “Necessary for” means that but for the facility design safety review, the costs would not have been incurred and that the costs cover only those activities and items without which the facility design safety review cannot be completed.
(a) Costs qualifying for cost recovery include, but are not limited to—
(1) Personnel costs based upon total cost to PHMSA;
(2) Travel, lodging and subsistence;
(3) Vehicle mileage;
(4) Other direct services, materials and supplies;
(5) Other direct costs as may be specified in the Master Agreement.
(b) [Reserved]