These regulations apply to all recipients of financial assistance for the construction or operation of facilities and equipment for use in providing mass transportation under: (a) The Federal Mass Transit Act of 1964, as amended (49 U.S.C. § 1601 et seq.); (b) 23 U.S.C. § 142 (a) and (c); and 23 U.S.C. § 103 (e)(4).