Arsenic is a naturally occurring element in rocks, soils, and the waters in contact with them. It is found in ground water as the result of minerals dissolving from weathered rocks and soils. This site links to data, maps, and more.
Research findings and examples of application to real problems--chemical reactions between nitrate, iron, and oxygen can affect the mobility of trace amounts of arsenic.
U.S. Department of the Interior |
U.S. Geological Survey