COLUMBIA, S.C. (AP) — Duke Energy last week assured South Carolina Public Service Commission members that the utility’s coal ash pits in the state were safe and designed differently from the one that failed at its Eden, N.C. plant, coating a 70-mile stretch of the Dan River in toxic sludge.

What the executives didn’t mention was the company had just been cited by South Carolina environmental regulators a month earlier for problems at its W.S. Lee Power Station along the Saluda River. The notice of violation from the Department of Health and Environmental Control said Duke failed to file critical monitoring reports for three years, and had problems with erosion and seepage around an earthen dam that holds back tons of coal ash.