S.C. Code § 59-67-460
Any county board of education may at any time contract for any part or all of its transportation services with private individuals or contractors for the furnishing of such services. In any such instance the county board of education shall execute the contracts. The county board shall be responsible for the payment of all sums due under contracts so entered into and shall receive aid from the State for pupils thus transported only on the basis of the average per pupil operating cost of State-owned equipment for the current year as determined by the State Board of Education.
The Board may enter into agreements with county boards of education whereby pupils living in isolated areas may be transported by special arrangements when such transportation can be provided at lower cost than by operating a regular bus route.
S.C. Code § 59-67-460