A study of groundwater near Ameren Missouri’s Labadie power plant found no threats to drinking-water supplies from coal ash, the utility says.

The study, released Monday, concludes that the plant’s coal ash practices “are not adversely impacting human health” through current drinking water use from groundwater or the Missouri River.

Ameren commissioned the study by AECOM, an environmental consulting firm based in Los Angeles. Coal ash is produced by burning coal to generate electricity.

AECOM’s conclusions were based on studies of 16 water samples from the Missouri River and Labadie Creek, plus 90 samples of groundwater near the plant in Franklin County. The coal-fired plant, which began operating in the 1970s, can produce 2,407 megawatts of electricity.

In its 217-page study, AECOM said it found no elevated levels of sulfate or boron in groundwater or surface water near the plant. High concentrations of the two chemicals in water sources would indicate a release of coal ash. Boron and sulfate are more soluble than other elements found in coal ash and would be the first to be detected in groundwater, the study said.