Dr. V.K.Maheshwari, M.A(Socio, Phil) B.Sc. M. Ed, Ph.D
Former Principal, K.L.D.A.V.(P.G) College, Roorkee, India
A mineral is pure inorganic substance that occurs naturally in the earth’s crust. More than two-thousand minerals have been identified and most of these are inorganic, which are formed by various combination of elements. Mineral are naturally occurring elements or compounds that have been formed through slow inorganic processes. These are more than 3000 minerals species, most of them having chemical composition, crystal, hardness, colour and opacity
Our civilization is based on mineral resources. All materials (fuels, metals, water, etc.) needed for modern society are derived from the earth’s crust, whether directly or indirectly. The naturally occurring materials (in form of ore) obtained below the earth’s crust having a definite structure and chemical composition are called minerals.
The minerals from which metals and non metals is extracted are known as ores. Rock is formed naturally by mineral deposition. According to their origin, rocks are divided into three types:
(i) Igneous rock
(ii) Sedimentary rock
(iii) Metamorphic rock.
The ores yield metal like iron, copper, aluminium, gold, silver, platinum, while non- metallic materials like cement, sulphur, phosphorus, diamonds and chemical by products of petroleum refining are vital to industry.
Classification of minerals:
On the basis of predominant anions or anionic group minerals can be classify as : (i) Silicates minerals (ii) Native elements (iii) Sulphide minerals (iv) Oxide minerals (v) Halide minerals (vi) Hydroxide minerals (vii) Carbonate and nitrate minerals (viii) Sulphate minerals (ix) Borate minerals (x) Tung state, chromate and molybdate minerals (xi) Phosphate, Arsenate and Vanedate minerals.
All the minerals are non renewable and valuable because they are stronger than any other materials, and they can be melted and cast into shape with a good conductor of electricity.
Marine mineral resources
The deep sea basins are found to contain enormous quantities of minerals such a manganese, cobalt-nickels and copper. The salt, magnesium and bromine are also discovered from marine Marine mineral resources in India are of three types:
1. Terrigenous minerals: In Maharashtra, Kerala and Tamil Nadu, Andhra Pradesh and Orissa with Ilmnite, monazite.
2. Biogenous deposits: In Kerala, Gulf Kutch, A & Nicobar with calcium, carbonate.
3. Chemogenous deposits: Manganese nickel, cobalt and copper.
Categories of Mineral Resources
Mineral resources can be divided into two major categories:
• Metallic Mineral Resources
• Non-metallic Mineral Resources
Characteristics of Metallic Minerals
Metallic Minerals are metals that are hard substance and conduct heat and electricity with a characteristics of luster or shine. For example: Gold, Silver, Tin, Copper, Lead, Zinc, Iron, Nickel, Chromium, and Aluminum.
Metallic minerals contain metal in raw form .Metallic Minerals present a metallic shine in their appearance. They contains metals in their chemical composition and are potential source of the metal that can be got through mining.
Metallic minerals are further classified into Ferrous metallic minerals and Non-ferrous metallic minerals.
Ferrous Minerals are those mineral that contains iron, for example: Iron ore, maganese and Chromites.
Non-Ferrous Minerals are those minerals which do not contain iron, for example: gold, silver, copper and lead.
Non-metallic minerals
Non-metallic minerals are a special group of chemical elements from which no new product can be generated if they are melted. For example: sand, gravel, gypsum, halite, Uranium, dimension stone.
Non-metallic minerals are minerals which are either present a non-metallic shine or lustre in their appearance.These minerals do not contain extractable metals in their chemical composition.
Use of Minerals
The earth’s resources have been used by all cultures throughout history. The earliest uses of the earth’s resources involved water, salt and simple tools made from rocks. The quantities of various mineral resources used by particular societies vary widely but generally correspond per capita to the nation’s degree of development and standard of living
The use of minerals depends upon its deposits. Some countries are rich in mineral deposits, while others have no deposits. The greatest use of minerals depends on its properties. Minerals are used in almost all industries. Gold, silver and platinum are used in the jewelry industry. Copper is used in coin industry and for making pipes and wire. Silicon obtained from quartz is used in the computer industry. Aluminum is light, strong and durable in nature, so it is used for aircraft, shipping and car industries.
The Indian Scenario
A variety of minerals are found in India .On the basis of properties, minerals are broadly classified into metallic minerals and non-metallic minerals. Manganese, copper, aluminium, zinc, iron, bauxite, gold, lead, etc are metallic minerals. Metallic minerals are mainly occur in igneous and metamorphic rocks. Diamond, gypsum, mica, kainite, stones, potash, etc are non metallic minerals.
Manganese- Manganese is used in steel industries and in making paints, glass, insecticides, batteries, chemicals, bleaching powder, etc. India stands second in the reserves of manganese in the world. Manganese ore is exported from India.
Iron ore- Iron ore is used in the manufacture of steel and iron. Haematite, limonite, magnetite and siderite are the varieties of iron ore. Iron ore is a basic and important raw material of most of the manufacturing industries.
Mica- Mica is used in electrical and electronics industries. It is also used in production of medicines, paints, etc. Mica has an insulating property.
Copper- Copper is a good conductor of electricity. Copper is used for making alloys, electric wires and utensils. It is also used in the manufacture of medicines. The demand of copper is always more due to its non-rusting property.
Lead- Lead is a heavy and soft metal. It does not conduct heat. It is used in the manufacture of ammunition, glass, rubber, paints, etc.
Bauxite- Bauxite is used in industries as raw materials. India has large deposits of bauxite ore. It is used in industries which manufacture ships, aeroplanes, automobiles, electric wires, etc.
Mining of minerals
Mining refers to the process of extracting metals and minerals from the earth. Gold, silver, diamond, iron, coal, and uranium are just a few of the vast array of metals and minerals that are obtained by this process. Mining activities require the clearing of large areas of land.
In fact, mining is the source of all the substances that cannot be obtained by industrial processes or through agriculture. Mining reaps huge profits for the companies that own them and provides employment to a large number of people. It is also a huge source of revenue for the government.
Mining involves the physical removal of minerals from the crust of Earth. The mineral materials may be used as such or used for extraction of elements. As minerals are exhaustible resources, it becomes essential to conserve these resources.
There are three major stages in mineral extraction exploration, mining and mine reclamation.
The Steps of Mining:
Generally these are the stages of mineral exploration
Area Selection:
The most important stage, it is important to choose an area that is possible to find ore deposits easily, cheaply and quickly
Target Generation:
This stage involves investigation of the geology throughmaps, geophysics, and testing the surface and subsurface minerals of the area.
Resource Evaluation :
This stage lets you know the quality and quantity of the mineral in the area. This is achieved mainly by drilling.
Reserve Definition:
Converts an ore resource to a mineral reserve. Similar to resource evaluation, except a lot more detailed and thorough
Profit Planning :
This step involves planning out a mine to evaluate the economically recoverable portion of the deposit.
Mine Construction:
This step is physically making the mine. You have to make itso there is access to an ore body.
Mining:
This step is the actual excavation of minerals from the ground. This is achieved in many different ways, depending on what type of mine it is and whatyou want to take out of the ground
Ecological Rebuilding:
This means returning the land as much as you can to its former self, after all the mining is done.
Mining and quarrying methods-
The method used to extract minerals depends on the deposit size, shape, depth beneath the surface and grade. A choice is made between surface mining and underground mining.
Surface mining is less expensive, safer and involves fewer complications with air, electricity, water and rock handling. However, surface mining has a greater environmental impact than underground mining. Thus, surface mining operations disturb the surface more seriously.
In open pit mines, extraction proceeds by drilling, blasting, loading, transporting and dumping the ore out of the pit. In strip mining of coal, clay, bauxite, tar sands, phosphates, iron ores, etc., overburden is removed and dumped to the rear and the ore is scooped up and loaded into trucks.
Deep mines are extracted using underground minining methods. In most mines, ore extraction and mine development involve drilling and blasting, and removal with mechanical diggers onto underground railway cars or dump trucks that reach the surface through a shaft.
Hydraulic mining uses high-pressure water jets to wash soft sediments down an incline toward some form of concentration plant, where dense mineral grains (such as gold) and soft mineral grains (such as clay/kaolin) are separated.
Solution mining (leaching) involves dissolving the ore (Au, Ag, U, S, NaCl, etc.) with a liquid (water, cyanide, etc.). If the ore is extracted on site with solution mining, it is called in-situ leaching.
General Impacts of mining on the environment:
Energy Consumption:
Mining requires vast amounts of energy. The ore and rock has to be transported great distances by large vehicles, which require a large amount of energy in the form of gasoline. Underground mines need extensive hoisting systems to transport the minerals, which also require energy. Controlling the temperature of mines deep underground is very energy consuming as well. Pneumatic equipment, which is used a lot in the mining industry, also takes energy. Smelting ores and metal requires lots of energy
Air:
Mining has a great effect on the quality of the air. Since mines need to blast through rock to get to an ore, dust may be produced in the process. Coal mines release methane, which contributes to environmental issues because it is a greenhouse gas. Non-vegetated or uncapped tailing dams release dust, and when radioactive elements are found in the ore, radiation is emitted. Heavy metals, such as sulphur dioxide, may be polluted into the air by unsafe smelter operations with insufficient safeguards. The gold mining industry is one of the most destructive industries in the world, because of all of the toxins that are released into the air. Acid rain and smog are also some side-effects of mining.
Water:
Mines use a lot of water, though some of the water is reusable. Sulphides-containing minerals negatively impacts groundwater. This happens from both surface and underground mines. Another way surface and underground water are affected is through tailing dams and waste rock heaps, because they are a source of acidic drainage water. Leftover chemical deposits from explosives are usually toxic, and increase the salinity of mine water, as well as contaminating it. Groundwater can be directly contaminated through “in situ” mining, in which a solvent seeps into un-mined rock, leaching minerals. Release of toxic chemicals into the water is obviously harmful for the flora and fauna of the water bodies. Besides the pollution, mining processes require water from nearby water sources. For example, water is used to wash impurities from the coal. The result is that the water content of the river or lake from which water is being used gets reduced. Organisms in these water bodies do not have enough water for their survival.
Previously buried metal sulfides are exposed during mining activities. When they come in contact with the atmospheric oxygen, they get converted into strong sulphuric acid and metal oxides. Such compounds get mixed up in the local waterways and contaminate local rivers with heavy metals. Chemicals like mercury, cyanide, sulphuric acid, arsenic and methyl mercury are used in various stages of mining. Most of the chemicals are released into nearby water bodies, and are responsible for water pollution. In spite of tailings (pipes) being used to dispose these chemicals into the water bodies, there is always a possibility of a leak. When the chemicals slowly percolate through the layers of the earth, they reach the groundwater and pollute it.
Land:
There are many environmental concerns about the effects mining has on the land. Trees need to be cut down in order to have a mine built, and whole forests could be destroyed. Mining involves moving large quantities of rock, and in surface mining, overburden land impacts are immense. Mining activities also may lead to erosion, which is dangerous and bad for the land. It destroys river banks, and changes how the river flows, where it flows, what lives in it, etc. Despite measures being taken to release the chemical waste into the nearby rivers through pipes, a large amount of chemicals still leak out onto the land. This changes the chemical composition of the land. Besides this, since the chemicals are poisonous, they make the soil unsuitable for plants to grow. Also, the organisms that live in the soil find the polluted environment hostile for their survival.
Large-scale deforestation
Mining requires large areas of forest area to be cleared so that the land could be dug into by the miners. For this reason, large-scale deforestation is required to be carried out in the areas where mining has to be done. Besides clearing the mining area, vegetation in the adjoining areas also needs to be cut in order to construct roads and residential facilities for the mine workers. The human population brings along with it other activities that harm the environment. For example, various activities at coal mines release dust and gas into the air. Thus, mining is one of the major causes of deforestation and pollution.
Ecosystem Damage:
Mines are highly damaging to the ecosystems surrounding them. Many different types of mines affect many different types of ecosystems. Many of the toxins and tailings that are discharged from the mines can disrupt and disturb the way animals live, and their health. Mining can completely destroy ecosystems by adding or taking out something from the animals’ everyday lives, therefore throwing the whole thing out of balance.
Loss of Biodiversity
The forests that are cleared for mining purposes are home to a large number of organisms. Indiscriminate clearing of the forests leads to loss of habitat of a large number of animals. This puts the survival of a large number of animal species at stake. The cutting down of trees in itself is a big threat to a number of plants, trees, birds and animals that dwell in the forests.
Health and Safety:
Mining can be very safe, but often it is extremely dangerous.Underground mining is usually more unsafe than surface because of the poor ventilation and visibility, as well as the rock fall hazards. The biggest health risks are from dust,which can cause breathing problems. Sometimes the liquid waste that is generated after the metals or minerals have been extracted is disposed in a mining pit. As the pit gets filled up by the mine tailing, they become a stagnant pool of water. This becomes the breeding ground for water-borne diseases causing insects and organisms like mosquitoes to flourish.
Impact on environment of mining
Much of the impact of mining is obvious. The disruption of land otherwise suitable for agricultural, urban or recreational use; the deterioration of the immediate environment through noise and airborne dust; and the creation of ore of the most dangerous environments for workers and potentially hazardous for the public are all environmental problems associated with mining. However, mining is a relatively short-term activity, and much can be done both to limit environmental damage during mining and to restore the land when mining operations are complete. Today, in many countries, legislation has been enacted at nearly all levels to ensure that extreme restrictions could make mining completely uneconomical. Unfortunately, the absence of adequate controls over some mining activities in the past has left numerous scars on the surface of the earth and led to resistance among many members of the public toward new mining activities in their areas.
Fortunately, many underground mines leave little evidence of their presence, even after mining operations have ceased. They are usually filled by percolating ground water over time, but the rocks are usually strong enough to hold in spite of abandoned mine openings and passageways. Sometimes the old mines can be put to very good use. Old underground mines can be used as storage areas for grains, seeds, burial of nuclear wastes, and truck parking.
When an open pit mine closes, a large hole remains with no readily available waste rock to fill it. The pit slopes are often too steep for plantation. If the water table is high enough, the bottom of the pit may flood, creating an artificial lake. Therefore, very large open pit mines are difficult, if not impossible, to reclaim. Smaller open pits may be filled with waste rock. In some places, surface mines can be reclaimed to form small lakes and wetlands mat support fish, birds and other wildlife. Underground mines do not lead to such drastic disruptions of the surface as open pit and strip mining, but a new hazard known as subsidence can be encountered. Subsidence under towns and roads can leave homes uninhabitable and transportation severely disrupted.
In addition to the impact that mining activities may have on the, landscape, the environment may be disrupted over a wider area by changes İn the distribution and chemistry of surface waters or ground water. Water passing through the mines or dumps becomes acidified, later finding its way into rivers, streams or the local groundwater system. Many streams can be affected by abandoned mine works.
Disposal of mining wastes
Nearly all mining operations generate waste rock, often in very large amounts. Strip mining waste can be used in reclamation, but an alternative method of disposal must be found for underground mining operations and most kinds of open pit mining. Usually, this simply involves dumping the wastes İn piles at the surface next to the mine workings.
Sometimes, die waste rock is put back into me openings created by the mining . Piles of waste rock may be dangerous because of the possibility of sliding. Alternatives to the dumping of mining wastes, such as the use of them to fill land, are likely to be expensive and impractical in most cases. Waste dump slopes can be lowered and re-vegetation can be achieved.
Dredging and ocean mining
Dredging involves removing unconsolidated material from rivers, streams, lakes and shallows seas with machines such as bucket-ladder dredge, drag-line dredge or suction dredge. There is no mechanical pollution from dredging, but the process disperses large quantities of fine sands and silt having severe effects on fish and other wild life that require clean water to survive. Ocean mining for Mn nodules involves significant disruption to ocean water and biological system. Currents, sedimentation patterns and erosion patterns are changed by ocean mining operations.
Well drilling and production
Drilling wells are used to explore and produce oil, gas, brine, geothermal fluids. Blow out and fire hazards can create severe pollution. Oil and brine spillage and seepage must be carefully controlled.
Affects of used resources on the environment
The burning of fossil fuels in power stations, homes and automobile engines results İn gases, particles and excess heat being emitted into the environment. The use of nuclear fuels generates toxic radioactive waste products requiring special disposal. Oil refining and metal/mineral production also generate wastes and pollutants.
Acid pollution
The most important pollutant of the hydrosphere is acid in the form of acid rain and acid mine drainage. Acid mine drainage formed by dissolution of pyrite dissolves more pynte, thus accentuating the effects.
Burning fossil fuels
The burning of fossil fuels in automobiles, power plants and heating systems creates air pollution. The burning of solid waste and smelting also generates air pollution.
Disposal of nuclear wastes
The mining and processing of uranium ores, the manufacture of nuclear fuels, the use of fuels in nuclear power stations, and nuclear weapons manufacture all generate waste products requiring disposal. The long-term disposal of radioactive wastes is still an unresolved problem.- Low-level wastes generally have radioactivity less than 1000 times the acceptable level in the environment. Large quantities of this type of waste are produced at uranium mines.. High-level radioactive wastes from the nuclear power industry account for roughly 95% of the radioactivity.
Possible Solution for decreasing negative impact
To decrease negative impact on the environment without significantly disrupting the supply of minerals.We believe this objective can be attained through a method of mining known as“sustainable mining. Sustainable mining is an effective way to reduce the impact of mining on the environment. It is a huge step towards becoming more environmentally and ecologically-friendly. They will meet society’s needs for minerals and metals, while demonstrating responsibility to social, economic and environmental issues. They demonstrate these traits through exploring, discovering, developing, producing, distributing and recycling the products. The mining companies should keep contributing to the protection of the employees, communities, customers and the natural environment by promoting the safe and environmentally-friendly production,use and recycling of metals and minerals, minimizing effects on the environment through all stages of the mine’s development, from exploration to closure, working with communities about the issues of abandoned mines, and using new technology and innovations to practice continuous improvement.One of the chief problems of sustainable mining is that the mining companies simply don’t have enough money to implement sustainable mining without outside financial assistance. All non-essential mining must be reduced in size to the absolute minimum possible.
As for the treatment of abandoned mine sites that contaminate the environment, there are several different treatments for the different types of pollution .
Acid Mine Drainage: Acid mine drainage is currently treatable with several different chemicals that neutralize the acid: calcium carbonate, calcium hydroxide, calcium oxide,sodium carbonate, sodium hydroxide, and anhydrous ammonia.
Tailings: The disposal of tailings has always been difficult. In the past, they have been disposed in numerous ways, almost none of them environmentally friendly: stored in ponds, dumped into rivers, dumped into oceans, etc. However, there are two more eco-friendly and less unsightly methods that can be used. The first is disposal into underground caverns or voids left from mines. This method is good because it leeches fewer minerals into the water table, because it reduces the risk of the cavern collapsing ,and because it hides the ugly tailings from view. The other method is depositing tailings into abandoned open pit mines. The main advantages of this method are that it gets rid of the sight of the tailings, and fills up the hole left from the open pit mine
Air pollution: Unfortunately, there is little we can do about pollution already in the atmosphere. All we can do is prevent more from getting into it.
Land Pollution : Land pollution can be rectified through standard reclamation efforts;however it must be made mandatory to reclaim abandoned mines.
Water Pollution: The majority of water pollution can be treated through neutralization. Other acidic chemicals in the water can also be treated by being pumped to treatment plants
Conclusion
Mining Supporters includes mine employees, mining companies, investors, mining lobbyists, civilians in favour of mining, and politicians in favour of using the “current methods of mining”.Mining Companies: Mining companies support the current methods of mining for obvious reasons. Mining is how they turn a profit. They believe that the benefits of mining [think money] far outweigh the disadvantages.
Mining companies believe that what they do is worth it. They do not care about the environment; their sole value is profit. They believe that environmentalists are wrong, and that what they do is for the greater good. They think that economy outweighs the environment. They know that the things they are mining (for the most part) are necessities that are used in everyday life, so they think it is vital to keep mining and extracting those materials, even if it means risking the health of the planet.
Mining Opposition includes environmentalists, civilians against the current methods of mining, and politicians against the current methods of mining .Environmentalists: Environmentalists are people who are “concerned for the preservation, restoration, or improvement of the natural environment, such as the conservation of natural resources, prevention of pollution, and certain land use actions.”As such, they are opposed to the current methods of mining when they harm the environment. By definition, all people who oppose the current methods of mining are environmentalists. They believe that the environment comes first, that the current methods of mining are wrong because they harm the environment, that there are more eco-friendly ways of mining to retrieve minerals, and that the public should be aware of the degradation of the environment caused by these methods of mining. These people are the backbone of the opposition to mining.
Minerals are formed by inorganic processes of long duration. Minerals are exhaustible and non-renewable resources. Extraction of minerals has increased at large scale to meeting the ever increasing population of country. Due to improper and excessive use, minerals in certain regions are on the verge of extinction. Hence, there is a need of conservation of minerals. Avoid use and acceptance of minerals which are not essential. Modern technology plays an important role in the conservation of minerals. Recycling is the perfect form of mineral reuse.
As a result, miners have to exploit and use minerals in an environmentally friendly way because the globalization of environmental concerns presents complex ethical problems that we have just begun to address. Today, miners cannot ignore the concern that the earth is reaching its limit of mineral-related pollution.