LIMESTONE, Maine — Although PFAS contamination hasn’t been found in drinking water supplies in the area around the former Loring Air Force Base, the use of a PFAS chemical to put out fires on Loring’s runway has prompted the U.S. Air Force to examine how far the chemical has spread into the natural environment. Looking into the spread of Aqueous Film Forming Foams, or AFFF, and assessing the potential ecological and human health risks is the latest phase in the Air Force’s investigation into PFAS contamination and will include a public meeting next week for area residents to ask questions.