Do you know what is in your well water? Many household wells in the state of Connecticut have higher than the recommended minimum levels of arsenic and uranium. These contaminants are naturally occurring elements coming into contact with the groundwater. The potential adverse effects on human health are well documented. Arsenic and uranium in groundwater in New England have been shown to have a strong association to the composition of the bedrock. In a 2016 Connecticut Dept. of Public Health report stated that private wells serve 23 per cent of Connecticut's population. The State does not require that existing private wells be routinely tested for arsenic, uranium, or other contaminants; consequently, private wells are only sampled at the well owner’s discretion or when they are newly constructed. The U.S. Geological Survey (USGS), in cooperation with the DPH, completed an assessment in 2016 on the distribution of concentrations of arsenic and uranium in groundwater from bedrock in Connecticut - Download the report here and see fig. 1. This report presents the major findings for arsenic and uranium concentrations from water samples collected from 2013 to 2015 from private wells.