USGS & CDC Estimate about 2.1 million people use wells high in arsenic

It's common to run into arsenic in soils and groundwater here in Midwest.  If you operate a well for your drinking water supply, get it tested.

Your state geological survey and local water monitoring council provide a lot of information on arsenic in drinking water - a great place to start for citizens with questions and concerns about arsenic in their drinking water.  Here is a link to the Indiana Water Monitoring Council's arsenic pages.