Note: This article was adapted from this link and revised.
On a hiking trail through a wooded area, you are enjoying the bird calls piercing the tranquil air. The babbling of a running brook provides a sense of complete serenity. The picturesque scene is shattered when you spotted dead fishes floating in the placid water.
An orange substance in the water provides a vital clue. The culprit? Acid mine damage! A gold, silver or copper mine nearby in its operation has sulfide minerals. In the course of mining, the sulphides exposed to air and water produced sulfuric acid.
Acid mine drainage is one of mining’s most serious threats to water. It was reported that acid runoff from the Summitville Mine in Colorado killed all biological life in a 17-mile stretch of the Alamosa River. Another related pollution of downstream water in many countries is the use of cyanide in gold mining.
Cyanide spills into groundwater can remain for long durations and poison drinking water aquifers. Groundwater polluted by cyanide can also contaminate hydrologically adjoining streams.
Cyanide usage in gold mining is popular because it easily combines with many metals especially gold. A sodium cyanide solution is generally used to leach gold from ore. When the leaching process is completed, the resulting waste known as tailings, is stored behind large dams.
Polluting waters with mine tailings causes mostly irrevocable damage – there is no feasible technology to remove and treat mine tailings from rivers, streams, lakes and oceans and even cleaning up part of the tailings disposed into these water bodies has an exorbitant price.
Therefore, keeping tailing dams safe is the most challenging task in the gold mining industry. When tailings dams leak or break, the result is substantial environmental impacts and public health risks.
Clean Mining, part of Clean Earth Technologies, offers a clean and green gold recovery process that removes cyanide as the primary means of leaching gold in medium to large-scale mining operations. It uses a non-toxic, non-flammable reagent to dissolve gold from ores that has proven to be as effective and much safer for people and the environment.