Naturally Occurring Arsenic in Southeast Michigan Ground Water

Previous studies of ground-water resources in Michigan by the Michigan Department of Community Health (MDCH), the Michigan Department of Environmental Quality (MDEQ), and the U.S. Geological Survey (USGS) indicate that there are several counties in the southeastern part of the State where concentrations of arsenic in ground water may exceed the recently revised U.S. Environmental Protection Agency (USEPA) maximum contaminant level (MCL) of 10 micrograms per liter [ug/L; also expressed as 0.010 milligrams per liter (mg/L)]. This MCL was established in January 2001.

 

EPA Arsenic in Drinking Water Basic Information

 

This study identified some geologic and hydrologic factors that affect the distribution, concentration, and toxicity of arsenic in ground water from eight counties in southeastern Michigan. A companion study in Oakland County has produced fact sheets showing the distribution of arsenic, nitrate, and chloride in ground water in Oakland County.