modifies the surrounding ecosystem. It can be divided into two major categories based upon their excavation types. The first is surface mining which is by far the most common in the present day. The second kind is sub-surface mining which includes underground mining¹. There are many different forms of mining, that all happen in different locations around the world. Some common forms of mining include hydraulic mining, placer mining, hardrock mining, and open pit mining, shaft mining, contour mining, and drift mining¹. All of them are dangerous to the environment and people living in surrounding areas.
Ecosystem changes caused by mining
Open pit mining techniques have devastating effects for the balanced ecosystem functioning. First, the mining site and the area needed for accessing the site is cleared of any trees. This increases soil susceptibility to erosion, leads to habitat fragmentation, and alters important ecologic cycles such as water retention. Clearing of trees also modifies weather in the area². Wind, heat or cold can easily pass through a clearing rather than an area covered with thick canopy. This means that the local temperature fluctuates more often, and puts the native flora and fauna at risk². Even worse scenario occurs when hills and large pieces of ground are removed with explosives or large excavating machines, which create a moon like landscape in the blink of an eye³. Additionally, chemicals are frequently used in the mining process, leading to contamination of the soils, water, and air⁴.
Gold rush destroying pristine streams
A popular mining technique with widespread ecological damage is hydraulic mining. This is where water is used to expose the precious metal or desired mineral for collection. Many times the water is pressurized, washing away sediments and chemicals with little being done to protect the ecosystem from the consequences⁵. An example of how an ecosystem can be changed by mining could be seen in early forms of gold mining in the United States from 1860-1884 in California and the Sierra Nevada. Gold mining companies searched for abandoned streams that were covered by rocks and mud where they excavated gold with the help of hydraulic mining. Powerful water cannons washed away the overburden revealing this precious metal underneath. However, this was an inefficient way to expose the gold and led to a bigger problem; a large amount of debris and millions of cubic yards of sediment were released downstream and caused many ecological problems including the mass killings of fish.
In fact, in 1860 on the Sacramento River, steamboats could not pass and 15,000 acres of farm land was flooded leaving farmers with about 5 feet of rocks, gravel and sand in their fields⁵. This eventually lead the farmers to take legal action against the mining industry. The case was called Edwards Woodruff v. North Bloomfield Gravel Mining Company and it went to the U.S. District Court in San Francisco. In 1884, the judge ruled that hydraulic mining was “a public and private nuisance” in favor of the farmers due to the negative externality, the mining industry was causing the farmers downstream and because there was not any mitigation or stream disposal regulation⁵.
Extreme destruction of rainforests by mining
In our precious rainforests occurs extremely destructive mining activity for gold, diamonds, copper and other precious metals. This way of mining is very disruptive to the ecosystem and wildlife, but it has also negative impact on the local people, whose safety is often neglected by greedy mining giants. Since gold can be found in river channels and on floodplains, a common way to extract it is by hydraulic mining and then by using a sluice box to separate gold from other sediments. Other than hydraulic mining having its own negative effects, chemicals used or produced in the process come with a heavy toxic burden for living organisms as well.
Mercury added to stick the pieces of gold together and form larger chunks poisons environment, and chemicals such as sulfuric acids and metal oxides pollute local waterways. These compounds are produced when metal sulfides that were previously buried come into contact with oxygen in the atmosphere³. Additionally, cyanide is oftentimes used to separate gold from rocks or other sediment. Although it is regulated, spills happen and have disastrous consequences.
For example, in 1995, there was a huge spill of a one billion gallons wastewater in Guyana. The water was laced with cyanide and was released into the tributary of the Essequibo river. The effects were widespread and included severe losses of flora, fauna, both aquatic and terrestrial, contamination of land used for agriculture, toxic pollution of the drinking water and economic losses from the decline of the river’s ecotourism³.
Overall, mining is a very dirty process that seriously affects ecosystems. With consequences ranging from changes to weather, deforestation, sediment loading, contamination of water, soil, and air, to the massive killing off of flora and fauna in the area. Additionally, local people, including indigenous communities, are often exposed to health reducing impacts. It is important to remember how everything in nature is connected and we must do our part to protect the environment for the future generations.