S.C. Code Ann. § 5-7-35

No ordinance of a municipality which affects the operation of any railroad, as defined by SECTION 58-17-10, is effective until a certified copy of the ordinance has been sent to the division superintendent or local agent of the railroad company affected, by certified mail, return receipt requested. If a municipality annexes an area in which a railroad company operates, any existing ordinance which affects the company is not effective until the division superintendent or local agent of the company has been sent a certified copy, by certified mail, return receipt requested, of the ordinance declaring the area annexed.