Exactly as I had thought, groundwater is not used as drinking water at the prison and never has been. You can't get exposed to TCE contamination by taking a shower in it. Leaking jet fuel tanks over a 50 year period could indeed have deposited a lot of JP-4 under ground. This is kerosene and probably not as toxic as trichloroethylene which was used extensively for cleaning aircraft frames and engines.
On-site and off-site groundwater do not represent a past, present, or future public health hazard. On-site groundwater has never been used as a source for drinking water at George AFB and no supply wells are expected to be installed there in the foreseeable future.