A new study of sediment in five recreational lakes in North Carolina shows that coal ash is more widespread in the state’s aquatic environment than was previously known. The contamination was shown to be present in four lakes where it had not previously been confirmed. One of the lakes, Mountain Island Lake on the Catawba River north of Charlotte, is also a metropolitan drinking water source.

The findings by researchers from Duke and Appalachian State universities were released last week. The results have implications for possible future steps that may be needed to address environmental risks from coal ash contamination. “The sediment quality [in these lakes] has been damaged,” said Zhen Wang, lead author of the study. “It has great implications for damaging the health of the aquatic ecosystem.” Naturally, Duke Energy denies that there are risks of concern.