The U.S. Environmental Protection Agency has set a new compliance standard for the presence of C8 in drinking water supplies near Dupont Washington Works.

The new standard is 0.40 parts per billion...replacing the 0.50 standard set three years ago.

By agreement with the EPA, Dupont is to take additional samples of private drinking water wells installed since 2006, and sample in some previously untested areas.

Dupont says there are between 10 and 15 wells covered by the order where water is not being treated.

C8 is a chemical used in the manufacture of Teflon at Washington Works.