The U.S. Geological Survey (USGS) Environmental Health Mission Area (EHMA) is providing comprehensive science on sources, movement, and transformation of contaminants and pathogens in watershed and aquifer drinking-water supplies and in built water and wastewater infrastructure in the Greater Chicago Area. The focus of chapter 1 is on assessing point-of-use (tapwater) drinking-water exposure pathways for a broad range of potential environmental contaminants and exploring infrastructure-related factors that could alter or transform chemical constituents or microbial communities in drinking...