S.C. Code § 58-5-330
Within twenty days after an order or decision is made by the commission, any party to the action or proceeding may apply for a rehearing as to any matter determined in the action or proceeding and specified in the application for rehearing and a rehearing must be granted if in the judgment of the commission sufficient reason exists. No right of appeal arising out of an order or decision of the commission accrues in any court to any corporation or person unless the corporation or person makes application to the commission for a rehearing within the time specified. The application must set forth specifically the ground on which the applicant considers the decision or order to be unlawful. The determination must be made by the commission within thirty days after it is finally submitted. If, after the hearing and a consideration of all the facts, including those arising since the making of the order or decision, the commission is of the opinion that the original order or decision, or any part of it, is in any respect unjust or unwarranted or should be changed, the commission may abrogate, change or modify it and, if changed or modified, the modified order must be substituted in the place of the order originally entered and with like force and effect.
S.C. Code § 58-5-330
2006 Act No. 387, Section 53, provides as follows:
"This act is intended to provide a uniform procedure for contested cases and appeals from administrative agencies and to the extent that a provision of this act conflicts with an existing statute or regulation, the provisions of this act are controlling."
2006 Act No. 387, Section 57, provides as follows:
"This act takes effect on July 1, 2006, and applies to any actions pending on or after the effective date of the act. No pending or vested right, civil action, special proceeding, or appeal of a final administrative decision exists under the former law as of the effective date of this act, except for appeals of Department of Health and Environmental Control Ocean and Coastal Resource Management and Environmental Quality Control permits that are before the Administrative Law Court on the effective date of this act and petitions for judicial review that are pending before the circuit court. For those actions only, the department shall hear appeals from the administrative law judges and the circuit court shall hear pending petitions for judicial review in accordance with the former law. Thereafter, any appeal of those actions shall proceed as provided in this act for review. For all other actions pending on the effective date of this act, the action proceeds as provided in this act for review."