The owner or owners of any line of railroad, not exceeding 60 miles in length, in the state of New Mexico, which has been or shall be constructed primarily for the purpose of carrying coal, lumber or the products of some other particular industry, may enter into private contracts for the carriage of persons or freight over such line of railroad without thereby becoming liable to control as common carriers or becoming subject to the obligations and duties of common carriers.
NMS § 63-4-9