30 C.F.R. § 881.6
(f) The State shall include in each project contract provisions to the effect that—
(4) To assure the use of local labor to the maximum extent practicable in the implementation of a project:
(i) Every contractor or subcontractor undertaking to do work on the project which is or reasonably may be done as onsite work, in carrying out such contract work shall give preference to qualified persons who regularly reside in the labor area as designated by the U.S. Department of Labor wherein such project is situated, or the subregion, or the Appalachian counties of the State wherein such project is situated, except: