Per- and polyfluoroalkyl chemicals, known commonly as PFAS, could take over 40 years to flush out of contaminated groundwater in North Carolina's Cumberland and Bladen counties, according to a new study from North Carolina State University. The study used a novel combination of data on PFAS, groundwater age-dating tracers, and groundwater flux to forecast PFAS concentrations in groundwater discharging to tributaries of the Cape Fear River in North Carolina.