Uranium in Well Water: A Growing Concern for Private Wells

Natural Occurrence

Uranium is a naturally occurring radioactive element found in certain rock formations, particularly granite, volcanic rock, and sedimentary deposits. It dissolves into groundwater under the right chemical conditions, especially in alkaline (high pH) water.

EPA Standard

The EPA MCL for uranium is 30 micrograms per liter (ppb). Health effects of long-term exposure above this level include kidney damage and increased cancer risk. Uranium also contributes to total radioactivity in water.

Affected Regions

Elevated uranium levels are most common in: New England (granite bedrock), the Rocky Mountain states, the Upper Midwest, and parts of the Great Plains. Wells drilled into crystalline bedrock are at highest risk.

Treatment

Ion exchange (anion exchange resin) is the most effective treatment for uranium, removing 95%+ at proper design. Reverse osmosis is also effective for point-of-use treatment. Distillation can reduce uranium levels. Water softeners may reduce uranium somewhat but are not designed for this purpose.