S.C. Code § 48-2-70
Under each program for which a permit processing fee is established pursuant to this article, the promulgating authority also shall establish by regulation a schedule for timely action by the Department of Health and Environmental Control on permit applications under that program. These schedules shall contain criteria for determining in a timely manner when an application is complete and the maximum length of time necessary and appropriate for a thorough and prompt review of each category of permit applications and shall take into account the nature and complexity of permit application review required by the act under which the permit is sought. If the department fails to grant or deny the permit within the time frame established by regulation, the department shall refund the permit processing fee to the permit applicant.
S.C. Code § 48-2-70