DUPO — The Illinois Environmental Protection Agency (Illinois EPA) has detected perfluorooctanesulfonic acid (PFOS), a type of PFAS chemical, in the Dupo Community Water System’s (CWS) most recent water sample, officials have announced.
The Illinois EPS said the most recent water sample showed PFOS at 4.5 parts per trillion (ppt), exceeding the federal Maximum Contaminant Level (MCL) and Illinois Class I groundwater quality standard of 4 ppt.
The Illinois EPA is notifying the owners and operators of the Dupo CWS, as well as those of the Columbia CWS and Prairie du Pont Public Water District, which can receive water from Dupo through an emergency connection. Under the Illinois Environmental Protection Act, water system operators must notify customers within five business days when groundwater contamination surpasses state quality standards and poses a public exposure risk…