Fact Sheet: Coal Combustion Residues (CCR) - Surface Impoundments with High Hazard Potential Ratings

This fact sheet by the Environmental Protection Agency list 44 coal slurry impounds that are highly susceptible to failure that could cause the loss of human life.

In response to an EPA information request on units handling wet or slurried CCRs, electric utilities have so far identified a total of 427 units managing slurried CCRs. Forty-four (44) of these units at 26 different locations have been assigned a high hazard potential rating, using the criteria developed by the National Dam Safety Program for the National Inventory of Dams. Hazard potential ratings are generally assigned by the State Dam Safety officials.

The National Inventory of Dams hazard potential ratings address the potential consequences of failure or misoperation of the dam. A high hazard potential rating indicates that a failure will probably cause loss of human life. The rating is not an indication of the structural integrity of the unit or the possibility that a failure will occur in the future; it merely allows dam safety and other officials to determine where significant damage or loss of life may occur if there is a structural failure of the unit. EPA’s assessment of the 26 facilities that have units with high hazard potential ratings continues to be an Agency priority. EPA has conducted on-site assessments, which are undergoing Agency review, at 11 of these facilities. The remaining 15 of these facilities have had state inspections within the past 12 months and EPA will be reviewing the reports from those inspections. EPA plans to make public the results of our assessments as soon as they are completed.