North Carolina regulators have ordered the chemical company Chemours, spun off by DuPont in 2015, to take additional steps to prevent pollution from PFAS chemicals from entering the Cape Fear River—including construction of a 1.5-mile subsurface barrier wall and groundwater extraction system.

Under an agreement reached Aug. 13 with the North Carolina Dept. of Environmental Quality and environmentalists, the company that manufactures chemicals such as Teflon and freon must reduce the level of toxins by 99% at four identified “seeps” that account for more than half of the contaminated groundwater reaching the river.