Minerals and mining
Minerals are naturally occurring inorganic substances essential to modern society, with a wide range of applications in various industries. They can be classified into metallic minerals, such as iron and copper, and nonmetallic minerals like salt and clay, as well as fossil fuels including coal and natural gas. Mining is the process of extracting these valuable resources, typically involving methods that can lead to significant environmental impacts. As populations grow and demand for minerals increases, concerns about resource depletion and ecological degradation have come to the forefront.
Mining operations can disrupt landscapes, pollute water sources, and generate harmful waste, contributing to issues such as acid mine drainage and greenhouse gas emissions. The mining industry is also a major contributor to climate change, with energy-intensive processes that release substantial amounts of carbon dioxide and methane. In response to these challenges, there are ongoing efforts to improve waste management and reduce emissions through cleaner technologies and adherence to environmental regulations. However, the balance between resource extraction and environmental stewardship remains a complex and pressing issue as the demand for minerals continues to rise.
Subject Terms
Minerals and mining
Definition
Minerals are naturally occurring inorganic substances with definite chemical compositions and characteristic physical properties. A rock is an aggregate of minerals. Minerals range in composition from native elements and metals, sulfides, halides, and carbonates to complex silicates, which are the most common rock-forming substances. Contemporary society depends on the availability of mineral resources: Metallic minerals such as iron, copper, aluminum, lead, and zinc; nonmetallic minerals such as salt, clay, gypsum, soil, and water; and such as coal, petroleum, natural gas, uranium, and palladium have all become necessary to the functioning of human civilizations.
With few exceptions, minerals are generally nonrenewable (exhaustible), since mineral resources generally have required long expanses of geologic time to develop and thus are present in effectively fixed amounts in the Earth. Minerals are extracted from the Earth by a variety of mining methods when the resource is economically viable. As world population increases exponentially and that population aspires to and achieves middle-class socioeconomic status, an escalating resource crisis has begun to develop that propels the mining of nonrenewable mineral resources. This industrial mining is coupled with many environmental concerns.
It is believed that Earth may have reached its maximum capacity to absorb environmental degradation related to mining. Potential environmental impacts of mineral mining depend on factors such as mine waste management, mining procedures, local hydrology, climate, rock types, size of operation, and related factors. Mining disrupts the landscape and can instigate mine subsidence, disrupting biological and water resources. Underground mining is generally more as a result of poorer ventilation and visibility and slope instability along mine walls. Moreover, the dust and toxic gases in mines lead to severe respiratory problems, and the possibility of exposure to radiation poses serious health threats.
Through mining processes, large amounts of material accumulate as waste that needs to be disposed of. Many copper mines, for example, extract ore that contains less than 1 percent copper. For many nonferrous metals, almost all the mined ore becomes waste. Artisanal mining, such as alluvial mining for gold and diamonds, often has impacts on landscapes, which are disrupted by trenches. These activities can lead to erosion and localized destruction of river banks. The waste also contains dangerous substances, such as heavy metals, which leach into the soil and result in the generation of acid or alkaline mine drainage.
The sulfide-containing minerals in metal mining get oxidized in the presence of air and react with water to form sulfuric acid. The acid mine drainage water contaminates surface and underground water. With the proliferation of the petroleum industry, numerous large-scale oil spills are becoming usual industrial accidents, and oil percolates through the soil and pollutes groundwater. The fuels and chemicals used in the mining industry are potential pollutants too. These chemicals left behind by explosives are usually toxic, and they increase the of water. Small-scale artisanal mining may also affect water where mercury is used to process gold. Excavation and removal of raw ore are only the initial stage in the mining process. The ores are processed at refineries, and the valuable portion is extracted by flotation, gravity, or chemical methods. The by-products of mineral refining are sulfur, arsenic, and radioactive substances that are dangerous if they are released into the environment.
Significance for Climate Change
The mineral mining industries contribute to global climate change. F are used to generate the energy required for moving mining equipment, mining procedures, ore processing and drying, transportation, and building operations. Burning them generates greenhouse gases (GHGs). The mining industry consumes large amounts of electricity to transport material by huge vehicles or extensive hoisting systems for underground mines. The underground mines become very warm with time, and cooling of deep underground mines is energy intensive. Refining metal ores by smelting also requires large amounts of energy. Surface mines pollute the air through blasting operations. Coal mines release methane, which is a primary GHG. However, methane can be captured through expensive processes to reduce the enhanced greenhouse effect.
Some members of the mining industry use ozone-depleting gases such as chlorofluorocarbons, hydrochlorofluorocarbons, and hydrofluoro-compounds for cooling. Similar to coal mining, the petroleum industry also has severe impacts on climate. The production and use of oil and natural gas makes a significant contribution to global warming by increasing atmospheric concentrations. Additionally, mining operations cause extensive deforestation, one of the major changes in landscape that lead to increased CO2 concentration in the atmosphere and promotes warming.
All these impacts can have long-term environmental and socioeconomic consequences and will be extremely difficult and expensive to address through remedial actions. Therefore, the mining industries are moving toward meeting standards of air and water quality set by Environmental Protection Agency (EPA) and other government agencies. At present, wastes from the extractive industries are properly managed in order to ensure the long-term stability of disposal facilities and to minimize water and soil contamination arising from acid or alkaline drainage and leaching of heavy metals.
The coal industries are participating in theClean Air Acts (1963-1990) and controlling methane emissions, although this is not economically feasible in many locations. Methane is removed from coal mines through degasification systems or mine ventilation systems during mining activities, or after mining has occurred. Over the 1990-2000 time period, the EPA reports that recovery of coal mine methane resulted in a reduction of methane emissions by 30 percent, or by the equivalent of approximately 25 million metric tons of CO2 per year. The terrestrial and geological sequestration of carbon and improvement of carbon uptake of soils are areas of research in mining industries that can reduce CO2 significantly. Moreover, the mining industries are promoting clean coal technologies to refine emissions reduction. The final goal is the development and implementation of zero-emissions mining industries. This requires both time and research dollars, and several organizations are participating and investing in this cutting-edge research endeavor, along with the potential for emissions savings.
Despite this progress, the mining industry continued to be a major driver of global climate change throughout the 2010s and 2020s. The process of mining valuable minerals causes both environmental damage and releases large quantities of greenhouse gases. Additionally, the industrial processes to refine those minerals into usable materials also release greenhouse gases. According to a 2022 study, the total environmental costs associated with the global mining and mineral industries caused as much as $5tn in damages each year. Nearly half of those costs were directly related to mining itself.
Bibliography
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Hoffert, Martin I., et al. “Advanced Technology Paths to Global Climate Stability: Energy for a Greenhouse Planet.” Science 298, no. 5595 (November, 2002): 981-987.
Raupach, Michael R., et al. “Global and Regional Drivers of Accelerating CO2 Emissions.” Proceedings of National Academy of Science 104 (2007).
Zagoruichyk, Anastasiia. "Emissions from Mining Cause 'Up to £2.5tn' in Environmental Damages Each Year." CarbonBrief, 7 June 2022, www.carbonbrief.org/emissions-from-mining-cause-up-to-2-5tn-in-environmental-damages-each-year/. Accessed 16 Dec. 2024.