WET ASH IMPOUNDMENT CLOSURE
Safety and Skill Count when Closing a Coal Ash Improvement
ENTACT completed the closure of a 140-acre wet fly ash impoundment containing approximately 13.4 million cubic yards of coal combustion residual (CCR). The project required draining the surface water via pumping and temporary drainage channels in the deposited ash and directing it to an area behind the main dam where a permitted outfall was located.
The overall scope of work for the project involved lowering the main dam, removing the saddle dam, and constructing a new spillway for both dams; draining surface water via pumping and temporary drainage channels; regrading exposed fly ash; and installing a multilayered capping system composed of geomembrane, geosynthetics, protective cover soil and vegetation. At project completion, our team managed over 5 million cubic yards of ash and soil, lined, and capped 140 acres, and pumped and managed more than 7 billion gallons of water.