The spill appears to be the third largest in U.S. history
Another huge coal ash  spill has polluted a river and currently threatens public drinking water supplies. On Feb. 3, Duke Energy reported that it spilled between 50,000 to 82,000 tons of coal ash into the Dan River near Eden, N.C. Coal ash is the waste left after burning coal in a power plant. Containing heavy metals and other toxic compounds such as arsenic, boron, chromium, selenium, mercury and lead, coal ash is a serious threat to aquatic ecosystems and local drinking water.
The spill is located on a stretch of the Dan River between Eden, N.C., and Danville, Va. An estimated 22 million gal of coal ash could already be in the Dan River moving downstream .
A security guard who noticed unusually low water in the ash pond at the shuttered coal plant lead to the discovery of the spill.
Upon investigation, Duke discovered that a 48-in. storm water pipe underneath the unlined 27-acre, 155-million-gal ash pond broke and drained tens of thousands of tons of coal ash and water into the Dan River. This coal ash spill appears to be the third largest in U.S. history.
In 2009, a U.S. Environmental Protection Agency technical report  classified Duke’s 53-year old Dan River ash pond dams “significant hazard potential structures.” Field inspections found them leaking and their surfaces sliding.
After Waterkeepers initiated enforcement actions for illegal coal ash water pollution at two Duke Energy coal plants in North Carolina last year, the state filed lawsuits accusing Duke of illegal pollution discharges from leaks in its coal ash ponds at all 14 of its coal-fired power plants in North Carolina. This includes Duke's Dan River Steam Station in Eden, N.C., about 30 miles north of Greensboro. Duke stopped generating electricity at the coal plant in 2012, however, the ash remains impounded at the site.