MTBE in groundwater of the U.S.: Occurrence, potential sources, and long-range transport

Groundwater is an important and valuable resource in the U.S. To some extent, groundwater is used in all 50 states to provide drinking water. In 1995, more than 50% of the population, more than 130 million people, relied on groundwater for drinking water supplies (Solley et al., 1998). About 30%, or 42 million, of these people obtained their water from privately owned wells (U.S. Geological Survey [USGS], 1999). The remaining 90 million people relied on groundwater from public water suppliers for their drinking water.