An airplane takes off near the site where Starkweather Creek exits Truax Field Air National Guard Base and flows through pipes that feed the water downstream toward Lake Monona in Madison, Wis. In 2019, the creek contained higher levels of PFOA and PFOS — two more scrutinized types of hazardous PFAS — than any other waters the Department of Natural Resources tested that year. Photo taken on Aug. 5, 2021. Isaac Wasserman/Wisconsin Watch