The EPA calls it Coal Combustion Residues (CCR), but laypeople call it coal ash - the residue from coal-fired power plants that is kept in slurry form in containment ponds. CCRs consist of more than just ash, however, and include coal slag and flue gas desulfurization (FGD) residue. They also contain low concentrations of metals like arsenic, selenium, cadmium, lead and mercury.
The EPA recently released a list of 427 coal ash containment sites throughout the country. Of these, it rated 44 as having a "high hazard potential."
According to the EPA, "A high hazard potential rating indicates that a failure will probably cause loss of human life."
The 44 sites are in 26 facilities in 10 states, mostly in the Midwest, South and West. The EPA has conducted on-site assessments at 11 of these facilities, and the rest have had state inspections within the past 12 months. All these assessments and inspections will be reviewed by the EPA, which will issue a public report on the results.