The Mason County Public Service District has completed upgrading two treatment plants to remove a chemical used to produce Teflon.

The upgrades were funded by DuPont Co. as part of a settlement in a class-action lawsuit filed by residents in Ohio and West Virginia.

Residents claimed the chemical C8 used at DuPont's Washington Works plant contaminated their water supplies. The plant is located near Parkersburg.

The carbon filtering systems installed at the PSD's Letart and Crab Creek plants are expected to remove the chemical from the water.

DuPont has funded similar systems at other water treatment plants located near its chemical plant.

DuPont recently agreed to provide water treatment systems at several private residential wells.