Contaminants found in many test wells

Nearly two-thirds of test wells in central Minnesota have found groundwater contaminated with excessive levels of nitrates, according to a state report issued on the eve of Gov. Mark Dayton’s water summit.

The report was commissioned by the Legislature and produced by the Minnesota Pollution Control Agency (MPCA) in an effort to assess the health of groundwater amid rising concern over pollution from agriculture, consumer products and urban development. Groundwater provides about 75 percent of Minnesotans with their drinking water and 90 percent of the state’s irrigation needs.

Among the highlights:

• 60 percent of test wells in the state’s central sands area, which is extremely vulnerable to agricultural pollutants, have nitrate levels exceeding the state’s drinking water standard of 10 parts per million. Nitrates can cause a potentially fatal condition in infants called blue baby syndrome.

• 30 percent of drinking water wells tested around the state had high levels of chloride from road salt, and many are getting worse.

• 37 pesticides have been detected in groundwater, but none exceed safe drinking water standards.


The state has also found 35 different chemicals from antibiotics, hormones, fire retardants and other products that can be harmful to humans. But the levels have been low.

The report also lists 30 recommendations to protect groundwater in the future. “It costs 10 to 30 times more to fix contaminated groundwater than to prevent contamination in the first place,” MPCA Commissioner John Linc Stine said in the statement.