S.C. Code § 7-13-830
When any person is so challenged, the manager must explain to him the qualifications of an elector and may examine his as to the same. If the person insists that he is qualified and the challenge is not withdrawn, his provisional vote must be received and placed in an envelope on which must be written the name of the voter and that of the challenger. The provisional votes must be kept separate and apart and not counted but turned over to the board of voter registration and elections or other authority having supervision of the election. At the meeting specified in either Section 7-17-10 or 7-17-510, whichever is applicable, this authority must hear all objections to these votes, and when no person appears or offers evidence before the meeting to sustain an objection made at the polls, the ballot is no longer a provisional ballot. When the challenger appears or produces witnesses or evidence in support of the challenge, the authority in charge must proceed to hear and determine the question. Its decision is final. Each provisional ballot which is no longer challenged and each ballot whose challenge was decided in favor of the voter must be removed from the envelope, mingled, and counted and the totals added to the previously counted regular ballot total of all precincts without attribution to a particular precinct. If the voting at the voting place is being done upon a voting machine, the managers must provide a paper ballot which must be placed in an envelope and treated as provided in this section.
Where, pursuant to Section 7-13-820, a person's name could not be verified by the board of voter registration and elections or where a telephone was not available and the person was allowed to vote a provisional ballot, the board of voter registration and elections, before the meeting, must certify to the authority in charge whether or not the voter is a qualified elector of the precinct in which he voted his provisional ballot. If the board certifies the person challenged is not a qualified elector of the precinct, this certification is considered an administrative challenge and is clear and convincing evidence for the meeting authority to disallow the ballot. Nothing in this section prohibits the county board of voter registration and elections from continuing any challenge administratively as long as it has evidence to sustain the challenge.
S.C. Code § 7-13-830