16 U.S.C. § 579a: Operation of aerial facilities and services

The Forest Service by contract or otherwise may provide for procurement and operation of aerial facilities and services for the protection and management of the national forests and other lands administered by it, including the furnishing, at the airbase, of facilities, equipment, materials and the preparation, mixing and loading into aircraft, with authority to renew any contract for such purpose annually, not more than twice, without additional advertising.