B2B Mineral

Environmental Risks of Mining

Environmental Risks of Mining

Different types of mining can have different environmental risks. In this article, we will dig into all aspects of mining environmental risks.

Open Pit mining

One of the most popular methods of mining for key minerals is open pit mining, which involves removing material from an exposed mine. Since strategic minerals are frequently only found in trace amounts, more ore must be extracted, making this sort of mining especially harmful to the environment.

Every stage of the open-pit mining process involves some level of environmental risk. Rock that has remained unexposed for geological ages is revealed by hard rock mining. These rocks include metallic particles, materials like asbestos, and radioactive elements when crushed. Remaining rock slurries, or tailings, are combinations of crushed rock and liquid that can leach radioactive and hazardous materials into bedrock if they are not effectively controlled.

Underground Mining

Tunnel failures and land subsidence are potential consequences of underground mining. Like open pit mining, it entails extensive movements of waste rock and plants. Furthermore, hazardous substances may be released into the air and water during underground mining, just like with the majority of conventional mining methods. Water becomes contaminated when it absorbs dangerous amounts of minerals and heavy metals. The area around the mine and beyond may be affected by this tainted water. As an amalgamating agent, mercury is frequently employed to help recover various valuable ores. When mercury tailings are improperly disposed of, they can contaminate nearby bodies of water and the atmosphere, which is a serious cause for worry. The majority of underground mining operations utilize suction dredges and hydraulic pumps to enhance sedimentation in neighboring rivers; blasting with hydraulic pumps destroys ecologically important topsoil holding seed banks, which hinders vegetation recovery. Biomes break down as a result of mining-related deforestation, which also exacerbates erosion.

In situ leach (ISL)

ISL mining is safer and better for the environment than traditional mining since the ore body is dissolved and then pumped away, leaving no waste rock or tailings behind and no surface disturbance. There is less demand for water during the mining operation, and there is no ore dust or direct contact with the environment. Nevertheless, metals in the host rock are frequently also dissolved by the powerful acids employed to dissolve the ore body. There is a serious risk to adjacent ground and surface water sources from the fluids left over from the leaching process, which frequently include high quantities of metals and radioactive isotopes. In addition, the environment may become more acidic because of the low pH of effluent from ISL mining.

Leaching Heaps

The main cause of heap leaching's environmental problems is the circuit's inability to retain process solutions. Toxic heap-leaching fluid releases into the environment can have an impact on the ecosystem's surrounding human population as well. Because solutions containing hazardous concentrations of heavy metals may overflow following a significant downpour or quick snowmelt, water balance is essential to heap-leaching projects. When cyanide is used to extract metals from oxidized ores, leach ponds that result have killed a large number of wildlifes, with 7,613 animals dying at cyanide-extraction ponds in California, Nevada, and Arizona alone between 1980 and 1989.

Mining Brine

To extract and evaporate the brine solutions and possibly release the hazardous substances back into the environment, brine mining is used. Because of the high salinity content of the solutions they are exposed to, well casings, pipelines, and storage tanks are susceptible to corrosion during the drilling and transportation of brine solutions, which can cause leaks and contaminate nearby bodies of water. At this time, there is no workable economic solution to remove sodium chloride contamination from an aquifer, and excessive amounts of the mineral can kill fish.

Particular Materials Contaminant

radioactive elements

Low concentrations of the radioactive isotopes that can concentrate in mine tailings are present in all REE-bearing minerals. Radionuclides are least containable (and mostly airborne) when they are released as dust during mining or from exposed waste rock stockpiles. After being separated into tailings, radiation can also seep into the ground and adjacent water sources if the tailings are not stored properly. After entering an ecosystem, radionuclides build up in plants. Higher concentrations of these substances are then absorbed by these plants, which causes them to move up the food chain. The issue of radioactive contamination has become so severe that China has outlawed the mining of monazite, and the US has implemented stringent regulations that essentially achieve the same result.

Metal & Dust

Several heavy metals that are frequently linked to health issues can be released into the air when mining operations break apart minerals. These particles, which are dust, can penetrate lung tissue and cause conditions including silicosis and pneumoconiosis, sometimes referred to as "Black Lung." One such mineral is riebeckite, which resembles asbestos. Flue dust is another type of dangerous dust produced as a result of mining fluorine. The Chinese Society of Rare Earths states that for every ton of REE produced, waste products including the heavy metals previously mentioned are created, yielding 8.5 kg of fluorine and 13 kg of flue dust.

Additional Mining-Related Environmental Issues:

Many more environmental problems are linked to mining in addition to the ones mentioned above:

carbon emissions

Similar to other heavy industries, mining depends on fossil fuels to produce the energy required to run a mine. Some nations have passed laws mandating emission credits to reduce these carbon emissions, yet many nations lack carbon output codes. Greater nations like China and Russia, as well as other emerging nations that mine significant amounts of key minerals, must adhere to some kind of environmental regulations.

habitat degradation and endangered species

The process of mining is intrinsically intrusive and has the potential to harm a landscape well beyond the boundaries of the actual mining site. Years after a mine closes, the damage it causes can still be felt in the form of increased greenhouse gas emissions, the demise of wildlife, and the degradation of habitat and land.

wastewater and water use

The majority of contemporary mining methods require a lot of water for extraction, processing, and waste disposal. These operations' waste products have the potential to contaminate neighboring water sources and decrease freshwater reserves in the mine's immediate vicinity. Some mines have used waste-water recycling technology, such as the Mountain Pass mine in southern California, which has led to a significant reduction in liquid waste and water needs (Molycorp, 2012).

Case Studies

To demonstrate the effects of inadequately regulated or monitored mines on the environment and surrounding community, we have gathered three brief case studies of ecologically hazardous mines.

2013 saw the anticipated opening of a mine in Greenland by Greenland Greenland Minerals and Energy Ltd. However, the tailings disposal plan called for depositing tailings in Taseq Lake, which will contaminate the lake as well as the rivers that flow into and out of it, as well as the ocean. These tailings would inject heavy metals, fluorine, and products of radioactive decay into the lake. Plans for the mine proceed despite the negative environmental impacts they would have since Denmark, the government supervising the project, does not have any environmental restrictions in place.

China

According to current estimates, China's "off-grid" miners illegally extract and export about 20,000 tons of rare earth elements (REEs) annually. Environmental protections are unlikely to be present in any of these illicit mines, therefore pollution, dust, and other pollutants are not being dealt with. This devastates the surrounding ecosystem and has an impact on the workers' health.

Molycorp

When a pipeline leading to evaporation ponds in the desert ruptured in 2002, radioactive and hazardous waste spilled into the desert floor, posing a threat to Molycorp's waste disposal at Mountain Pass. The subsequent discovery of previous leaks, in addition to economic considerations, led to Mountain Pass's closure and a thorough overhaul of its environmental procedures. But the harm was done, and the region and other water supplies are now perhaps permanently impacted.

These and other case studies show what happens when mining's negative environmental effects go unchecked or uncontrolled. The strategy for Mission 2016 would deal with these problems.

The price of doing nothing or acting

The ultimate cost to governments and communities would be catastrophic if nothing is done to address the numerous environmental issues that come with contemporary mining. For every ton of rare earth elements produced, Chinese mines already discharge 9,600–12,000 cubic meters of hazardous gas that contains hydrofluoric acid, sulfur dioxide, flue dust concentration, and sulfuric acid. One ton of radioactive waste residue and approximately 75 cubic meters of acidic wastewater are also produced. The expenses of environmental harm can be decreased, and in certain situations, prevented entirely, by taking preventive measures like tighter restrictions and appropriate waste disposal techniques.

For instance, the US business Molycorp invested USD 10 million on their paste-tailings operation, but in addition to producing less waste, the water and chemical reagents it was able to recover already compensated for the payment. "Although the operating cost of the paste tailings operation is expected to be greater than it would be for a tailings pond... we expect that increased water recycling and reduced environmental risks associated with the paste tailings facility will ultimately mitigate that additional cost". The goals of Mission 2016 include increasing recycling, using more environmentally friendly mining and refining methods, lowering the cost of environmental harm to the local community, and increasing government participation in the control of unclean mining operations

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