Various mining and extraction processes produce a tailings stream consisting of a slurry of particulate matter in water. These tailings often contain hazardous components that cannot be discharged directly into rivers and streams.
A common practice is to store tailings in ponds, which can be very large or encompass numerous sites. For example, recent estimates state Canadian oil-sands tailings ponds cover an area of about 200 square kilometers.
In the US, the Environmental Protection Agency has identified more than 500 ash and coal slurry ponds, mostly in the Appalachian coal-mining region. In Florida, phosphate mining results in the production of approximately 100,000 tons a day of phosphatic clays in the form of pond-stored slurry. It is very difficult to dewater, and the phosphate industry leaves about 40% of mined land in unstable clay settling areas.
Extrakt has developed the technology to meet the challenges faced by operators.