Hydrogeologic Settings and Groundwater- Flow Simulations for Regional Investigations of the Transport of Anthropogenic and Natural Contaminants to Public-Supply Wells? Investigations Begun in 2004

A study of the Transport of Anthropogenic and Natural Contaminants to public-supply wells (TANC study) was begun in 2001 as part of the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program.