What kinds of practices are involved in the gold mining process? How do these methods affect the environment?

For thousands of years gold mining has served as a shady process, and things haven't been looking any better lately since less easy access gold deposits are available than ever before. As a result, harmful practices in the gold mining process like cyanide heap leaching, open pit mining, and amalgamation are prevalent in the worldwide gold mining community.

One of the most frequently used methods for gold extraction from ore is cyanide heap leaching. In this process, the ore with the gold is mashed and piled in heaps. Then cyanide is sprayed on the heaps so that it drips down and joins the gold. Afterwards, the solution of gold and cyanide collects at the bottom of the heap where it's sent to a mill via a pump. At the mill, the cyanide is separated from the gold and then set aside to be used once again. Every stint of heap leaching lasts for several months. Due to the widespread and extensive nature of the process, the cyanide's harm to the environment is simply unavoidable. In order to get rid of the ore which has been tainted by the cyanide, these mines eventually form dams that are improperly structured. The dam failures in the past 20 years alone have been responsible for 3/4 of mining accidents. At the turn of the century, a gold mine dam failure in Romania caused the death of over a thousand tons of sea-life and polluted the drinking water of over 2 M people – all a result of cyanide mine waste that leaked into the river.

The majority of newly mined gold is the product of open pit mining. In this process, large quantities of rock are eradicated and the whole site is destroyed in the process. Obviously this is harmful to the environment of the gold mining site as it mars the ecosystem and opens enormous craters in the earth. Once the ore reaches the surface, it is processed to remove the precious metal from it. Unfortunately, this also results in large amounts of waste. Each ounce of gold produced via open pit mining is actually the product of approximately thirty tons of waste. A method of gold mining that is much more environmentally friendly involves the use of underground shaft mines. The problem is that the cost of this method is much higher than that of open pit mining. Underground shaft mining actually produces up to 10 times LESS waste than open pit mining.

Amalgamation is another process used to extract gold that is harmful to the environment as it emits mercury poisoning. In this process, mercury meets gold and forms an alloy known as amalgam. Once the mercury bonds with the gold, it can be extracted via nitric acid or heat evaporation, leaving only the gold. The problem with amalgamation is that it causes mercury vapor which can be detrimental to people and animals. In areas where this gold mining method is employed, people have been known to suffer from damage to their immune systems, brains, lungs, etc.

With all the dirty practices employed in various methods of gold mining, it's no wonder it's considered a dirty business!

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