S.C. Code Ann. § 3-7-140

If the United States declines to deal with the governing body of a county with respect to any political subdivision whose jurisdictional limits are within or coextensive with the limits of the county or if the jurisdictional limits of a political subdivision lie in more than one county, such political subdivision may make request of the United States for such payments in lieu of taxes as the United States may agree to pay and may enter into an agreement with the United States for the performance by the political subdivision of services for the benefit of a project and for the payment by the United States to the political subdivision, in one or more installments, of sums in lieu of taxes.