The grand jury subpoena delivered to the N.C. Utilities Commission on Friday directs the agency's staff to provide additional records involving the two coal ash dumps at Duke's Dan River Steam Station in Eden. A pipe running under one of the dumps collapsed Feb. 2, triggering a spill that coated 70 miles of the Dan River with toxic sludge.
The subpoena orders the state commission to produce the documents Tuesday at the U.S. District Courthouse in Raleigh.
Grand jury proceedings are secret and the office of U.S. Attorney Thomas Walker has declined to comment on the investigation. The new request is the first outside indication the probe is still ongoing since a flurry of more than 20 subpoenas issued to Duke and state regulators shortly after the spill.
"The commission complied with the U.S. attorney's first request for documents, which it received in February, and will comply with this request for additional documents," said Sam Watson, the general counsel to the state utilities board.
Duke spokesman Dave Scanzoni said Friday that the company has not received any new subpoenas.
N.C. Department of Environment and Natural Resources spokesman Drew Elliot also said his agency had received no new requests from prosecutors.
The extent of records sought by past subpoenas in the case suggests that prosecutors are not only looking at the Dan River spill, but also at the relationship between Duke and state regulators going back for many years and at what oversight has existed over the company's ash dumps across the state.
North Carolina lawmakers are currently debating a bill about what to do with Duke's 33 ash dumps at 14 power plants in North Carolina, which are located along rivers and lakes that cities and towns rely on for drinking water. State environmental officials say all of Duke's unlined waste pits, which contain more than 100 million tons of ash, are contaminating groundwater.
A key committee in the state Senate is scheduled to take up the bill Monday afternoon.