Water Balance
Make-up water is required to replace losses by evaporation, and to compensate for water removed with the solution bleed stream and the oxidized concentrate thickener underflow. Inflows to a GEOCOAT® system include water added with the concentrate, trommel or screen wash water, heap rinse water, and precipitation on pad and pond surfaces. Deficiencies in the water balance are made up by adding fresh water, either to the on-solution pond, directly to the screen wash water sprays, or as rinse water.
Depending on climatic conditions at the site, an emergency stormwater pond may be required to handle runoff resulting from storm events. A water balance analysis based on site-specific meteorological data determines the surge capacity required.
Tailings dam return water is not acceptable for use as make-up if it contains even traces of cyanide, thiocyanate, or other cyanide decomposition products, which are known to be toxic to the bacteria.