S.C. Code Regs. § § 103-731.7
Where a customer has been required to make a deposit, this shall not relieve the customer of the obligation to pay the service bills when due. Where such deposit has been made and service has been discontinued for reason of non-payment of bill, a utility shall apply the deposit of such customer toward the discharge of the customer's account and shall as soon thereafter as practicable refund the customer any excess of the deposit. If however, the customer whose service has been disconnected for non-payment, pays the full amount on his account within 72 hours after service has been disconnected and applies for reconnection, the utility may not charge an additional deposit except under the provisions of 1 of this rule.
S.C. Code Regs. § 103-731.7