Environmental contractors sample the groundwater from former fire training area #2 at former Wurtsmith Air Force Base, Michigan, several times a month to monitor PFOS/PFOA levels after groundwater passes through various treatment systems. AFCEC, a primary subordinate unit of the Air Force Installation and Mission Support Center, is leading the response effort under the Comprehensive Environmental Response, Compensation, and Liability Act to identify and mitigate PFAS impacts in the environment. (U.S. Air Force photo by Breanne Humphreys)