Abstract |
The release of over five million cubic yards of coal ash from the Tennessee Valley Authority's Kingston, Tennessee, facility in December 2008, which flooded more than 300 acres of land, damaging homes and property, is a wake-up call for diligence on coal combustion waste disposal units. We must marshal our best efforts to prevent such catastrophic failure and damage. A first step toward this goal is to assess the stability and functionality of the ash impoundments and other units, then quickly take any needed corrective measures. This assessment of the stability and functionality of the John Amos Bottom Ash Dam management unit is based on a review of available documents and on the site assessment conducted by Dewberry & Davis, LLC, personnel on Tuesday, September 8, 2009. Although we found the supporting technical documentation inadequate (Section 1.1.3), visual observations permit the conclusion that the embankments appear to be well maintained, safe, and structurally sound. There are no apparent indications of any unsafe conditions. The surveillance and monitoring program, however, are inadequate because no instrumentation is used to detect settling, displacement, and seismicity for the dam embankments. As detailed in Section 1.2.6, there are nine recommendations that may help to maintain a safe and trouble-free operation. |