Ameren Missouri says it plans to increase testing of water near its nuclear power plant in Callaway County.
The company is required to test water at its 14 monitoring wells only quarterly but says it will now test the wells every month.
The Jefferson City News-Tribune reports the decision comes about a month after contaminated water was found in a monitoring well near the plant's cooling tower.
The company and the Nuclear Regulatory Commission found the contamination was isolated to one area and didn't threaten public health. The chemicals leaked from pipes in a manhole near the monitoring well.
Barry Cox, plant senior director of nuclear operations, says routine tests on monitoring wells at the end of August did not find any evidence of elevated chemical levels.