S.C. Code § 23-7-40
The jurisdiction of a special state constable is confined and limited to the lands and premises acquired or being acquired by the United States Government for the use of the commission in Aiken, Allendale, and Barnwell counties. Nothing contained in this section confines or limits the jurisdiction of the constable to the lands and premises while in fresh pursuit of a person for a misdemeanor or felony committed in his presence or for a felony if he reasonably believes upon prompt information or complaint that the person has committed the felony. The failure of the United States to acquire title to any of the lands and premises within the boundaries of the site does not confine or limit the jurisdiction of a special state constable authorized by this chapter.
S.C. Code § 23-7-40