EPA Fact Sheet
Coal Combustion Residuals (CCR)
Surface Impoundments with High Hazard Potential Ratings
• Over the past several months, EPA has undertaken a concerted effort to identify and to assess the structural integrity of impoundments, dams, or other management units, within the electric power generating industry, holding wet-handled coal combustion residuals or CCRs.
• In response to an EPA information request on units handling wet or slurried CCRs, electric utilities have so far identified a total of 431 units managing slurried CCRs at 162 facilities from our first mailing. (The Agency sent out a 2nd mailing to an additional 48 facilities that were identified as also having units that manage wet or slurried CCRs. The information from this 2nd mailing is not included in this Fact Sheet at this time.). Forty-nine (49) of these units at 30 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.
• 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 facilities that have units with high hazard potential ratings continues to be an Agency priority. EPA plans to make public the results of our assessments as soon as they are completed.
• CCRs consist of fly ash, bottom ash, coal slag, and flue gas desulfurization (FGD) residue. CCRs contain a broad range of metals, for example, arsenic, selenium, cadmium, lead, and mercury, but the concentrations of these are generally low. However, if not properly managed, (for example, in lined units), CCRs may cause a risk to human health and the environment and, in fact, EPA has documented cases of environmental damage.
• Information on the presence of these is important to States, local officials, including first responders, and the residents of local communities so that appropriate preparedness efforts can be undertaken, reviewed, or maintained.
• Many States have active dam safety programs and in many cases, local government agencies, first responders, and the local community are involved in preparedness efforts. By providing this information, EPA’s goal is to assist in these efforts.
• The following 49 CCR management units at 30 facilities currently have a High Hazard Potential rating:
TVA has preliminarily reassessed the potential hazard classifications of the impoundments at each of its 11 fossil plants, in addition to the facility at the now-closed Watts Bar Fossil Plant. Five units at four TVA plant sites are rated “High.” Further information on TVA’s reassessment of coal combustion surface impoundments.
EPA will update this fact sheet as additional information becomes available.
Published Issue 1 – 2013 “Ash at Work” by ACAA