While properly constructed evaporation ponds are designed to protect the environment, ponds that are not properly designed, lined or installed can leak into surrounding soil and cause damage, either to the soil or to nearby lakes, rivers and streams or underground aquifers. As counterintuitive as it might seem, one of the most effective ways to combat contamination caused by mining sites, chemical pollutants or fuel storage facilities is with modern evaporation ponds. Cleanup at a contaminated site, which frequently features accumulated storm water or liquid that has leaked from underground storage tanks, is accomplished by reducing the volume of water through evaporation, leaving a thick sludge or crust that can be sifted or treated to reclaim any minerals and metals that are available for future use. The method is most effective at sites that contain a single form of contaminant, rather than a complex mix of chemical pollutants.
Such cleanup may be accomplished through temporary, short-term use of evaporation ponds, or it may stretch over decades. EPA-mandated remediation is typically a long-term effort that is constantly monitored and very costly. The efforts to remove toxic chemicals, polluted organic material that contains harmful bacteria or heavy metals is serious business, and use of an onsite evaporation pond can represent only the first step in a long process to clean up what has become known as a brownfield or EPA Superfund site.
