What is arsenic?
Arsenic is an element that occurs naturally in rocks and soil and is used for a variety of purposes within industry and agriculture. It is also a byproduct of copper smelting, mining and coal burning. Arsenic can combine with other elements to make chemicals used to preserve wood and to kill insects on agricultural crops.

Where and how does arsenic get into drinking water?
Arsenic can enter the water supply from natural deposits in the earth or from industrial and agricultural pollution. It is widely believed that naturally occurring arsenic dissolves out of certain rock formations. Some industries in the United States release thousands of pounds of arsenic into the environment every year. Once released, arsenic remains in the environment for a long time. Once on the ground or in surface water, arsenic can slowly enter ground water. High arsenic levels in private wells may come from certain arsenic containing fertilizers used in the past or industrial waste. It may also indicate improper well construction.

How can I find out whether there is arsenic in my drinking water?
If you suspect a problem and your drinking water comes from a private well, you may contact the Branch-Hillsdale-St. Joseph Community Health Agency’s Environmental Health Division for a list of laboratories that will perform tests on drinking water for a fee. The Michigan Department of Environmental Quality Laboratory may also help.

What should be done if there is an elevated amount of Arsenic in the well?
Heating or boiling your water will not remove arsenic. As water evaporates during the boiling process, the arsenic concentrations can actually increase slightly as the water is boiled. 

If your water tests above the acceptable EPA arsenic level (.010 mg/L), stop using your well water for drinking and cooking food. Use bottled water for these purposes. You may wish to have one or more additional water samples tested to confirm that your water is above acceptable levels. Consider connecting to a public water supply, if one is available. Another option is to drill a new well at a different depth, either deeper or more shallow.

In-home water treatment devices are not a permanent solution. These devices require maintenance and should be considered only after other options have been considered. Reverse Osmosis (RO) is not certified for the removal or reduction of naturally occurring arsenic, unless the supply water is pretreated by chlorination.