S.C. Code Ann. § 47-20-40
(A) The department shall promulgate regulations relating to land application rates for animal waste for animal feeding operations of a capacity for more than 420,000 pounds of normal production animal live weight at any one time. These rates must be based on the waste's impact on the environment, animals, and people living in the environment. In developing annual pollutant loading rates and cumulative pollutant loading rates, the department shall consider: