The only contract flying in the Coast Guard at the South Pole is helicopters; and they are flying off the back of our Polar Breakers. The C-130's that fly down there on skids are Air Guard Hercs. New York ANG I think. The C-130's in Kodiak, AK are now doing Arctic missions, but they started that mission after I left AK.
The DCA Program is only for military aviators. There is another program called AVCAD that would be for civilian pilots to enter CG aviation. Even if they were ATP rated, with tons of hours, the AVCAD program is an officer commission with a guarantee to attend Navy Flight School, so you would go to OCS, then spend 1.5 years playing flight student again, then go to an operational unit. If you google the Coast Guard Recruiting Manual, it will list the different pilot programs and how to apply.
As far as contract pilots go, we have limited opportunities. We do have a Civilian Contract Pilot program, but you have to be a prior CG rated pilot. We are using reserve pilots on extended active duty contracts to fill Pensacola and Corpus Christi Flight School Instructor billets. The CG does NOT have flying reservists, but we are looking at creating a program that mirrors the Navy program to allow reservists to do our flight school instructor training. We are so critically short in fixed wing aviators that we can't afford to give any to Flight School, but are required to if we want a higher student throughput. Catch 22 that we are having a hard time fixing.