Pursuant to 23 U.S.C. 136 , this part prescribes Federal Highway Administration [FHWA] policies and procedures relating to the exercise of effective control by the States of junkyards in areas adjacent to the Interstate and Federal-aid primary systems. Nothing in this part shall be construed to prevent a State from establishing more stringent junkyard control requirements than provided herein.
23 C.F.R. §751.1