CHARLOTTE, N.C. - After weeks of speculation, a federal grand jury convened in Raleigh to hear evidence in an investigation into Duke Energy.
The investigation comes in the aftermath of February’s coal ash spill that sent millions of tons of toxic ash into the Dan River.
The probe by the U.S. Attorney's Office resulted in 23 subpoenas issued to officials from Duke, the N.C. Department of Environment and Natural Resources, and possibly others.
U.S. attorney Thomas Walker declined to talk about the investigation, other than to say it's looking at whether there may have been criminal activity.
Legal experts said the federal investigation is serious and unusual.
"The fact that it's being convened is curious. This is not common," said Charlotte attorney Tony Scheer.
Scheer said the grand jury process is secretive and can be intimidating for witnesses who are under oath. "The prosecutor will be calling these witnesses into the room by themselves. They won't have any lawyers with them. There won't be a judge in there," Scheer said.
What prosecutors are trying to find out is unclear. Scheer said it’s possible grand jurors could be presented with evidence about the coal ash spill itself or about the relationship between Duke Energy and state regulators.
Environmental groups said the investigation is a wakeup call for Duke Energy.
Rick Gaskins, with the Catawba Riverkeeper Foundation, said it's already having an impact.
"Merely being the subject of an environmental investigation really should get a company's attention and cause them to rethink what they're doing," Gaskins said.
Last week Duke Energy announced that it would remove coal ash from ponds near Mountain Island Lake, which provides Charlotte's drinking water supply.
The grand jury is expected to continue hearing evidence through Thursday.
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