S.C. Code Ann. § 46-45-40: Established date of operation.

For the purposes of this chapter, the established date of operation is the date on which an agricultural operation commenced operation. If the physical facilities of the agricultural operation are expanded subsequently or new technology adopted, the established date of operation for each change is not a separately and independently established date of operation and the commencement of the expanded operation does not divest the agricultural operation of a previously established date of operation.