S.C. Code Ann. § 6-1-1010

(A) Revenues from all development impact fees must be maintained in one or more interest-bearing accounts. Accounting records must be maintained for each category of system improvements and the service area in which the fees are collected. Interest earned on development impact fees must be considered funds of the account on which it is earned, and must be subject to all restrictions placed on the use of impact fees pursuant to the provisions of this article. (B) Expenditures of development impact fees must be made only for the category of system improvements and within or for the benefit of the service area for which the impact fee was imposed as shown by the capital improvements plan and as authorized in this article. Impact fees may not be used for: (1) a purpose other than system improvement costs to create additional improvements to serve new growth; (2) a category of system improvements other than that for which they were collected; or (3) the benefit of service areas other than the area for which they were imposed.