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, the second largest Open Pit Copper mine in the world, Chile .]] Mining is the extraction of Valuable Mineral s or other Geological materials from the earth, usually (but not always) from an Ore body, Vein , or (coal) seam. Materials recovered by mining include Bauxite , Coal , Copper , Gold , Silver , Diamond s, Iron , Precious Metal s, Lead , Limestone , Nickel , Phosphate , Oil Shale , Rock Salt , Tin , Uranium , and Molybdenum . Any material that cannot be grown from Agricultural processes, or created Artificially in a Laboratory or Factory , is usually mined. Mining in a wider sense can also include extraction of Petroleum , Natural Gas , and even Water . HISTORY in Copper Country , Michigan, USA in 1905.]] The oldest known mine on archaeological record is the " and are believed to be sites where Neanderthal s may have mined Flint for weapons and tools. and at Timna . In , Canada, there also are ancient quartz mines near Waddy Lake and surrounding regions. Bruno, L. & Heaman, L.M. (2004). Structural controls on hypozonal oroganic gold mineralization in the La Rouge Domain, Trans-Hudson Orogen, Saskatchewan. ''The Canadian Journal of Earth Sciences'', Vol. 41, Issue 12, pp. 1453-1471. In the early colonial history of the Americas, "native gold and silver was quickly expropriated and sent back to Spain in fleets of gold- and silver-laden galleons." Vaden, H.E. & Prevost. G. (2002). ''Politics of Latin America: The Power Game''. New York: Oxford University Press, p. 34. in mining was first used in a mineshaft in Banská Štiavnica , Slovakia in 1627. Heiss, A.G. & Oeggl, K. (2007). Analysis of the fuel wood used in Late Bronze Age and Early Iron Age copper mining sites of the Schwaz and Brixlegg area (Tyrol, Austria). ''Vegetation history and Archeobiology'', Published March 16, Springer Berlin / Heidelberg. In 1762, the world's first mining academy was established in the same town. Mining in the and Sacramento originated as mining towns. PROCEDURE Steps of process # Prospecting or Exploration to find and then define the extent and value of Ore where it is located ("ore body") # Conduct Resource Estimation to mathematically estimate the size and grade of the deposit # Conduct a pre-feasibility study to determine the theoretical economics of the ore deposit. This identifies, early on, whether further investment in estimation and engineering studies is warranted and identifies key risks and areas for further work. # Conduct a Feasibility Study to evaluate the financial viability, technical and financial risks and robustness of the project and make a decision as whether to develop or walk away from a proposed mine project. This includes mine planning to evaluate the economically recoverable portion of the deposit, the Metallurgy and ore recoverability, marketability and payability of the ore concentrates, engineering, milling and infrastructure costs, finance and equity requirements and a cradle to grave analysis of the possible mine, from the initial excavation all the way through to reclamation. # Development to create access to an ore body and building of mine plant and equipment # The operation of the mine in an active sense # Reclamation to make land where a mine had been suitable for future use Techniques .]] Mining techniques can be divided into two basic Excavation types: In-situ Leach is a particular mining technique that is used to mine minerals ( Potash , Potassium Chloride , Sodium Chloride , Sodium Sulphate and Uranium Oxide ) which dissolve in water. EXTRACTIVE METALLURGY The science of Extractive Metallurgy is a specialized area in the science of metallurgy that studies the extraction of valuable metals and minerals from their ores, especially through chemical or mechanical means. Mineral Processing (or mineral dressing) is a specialized area in the science of metallurgy that studies the mechanical means of crushing, grinding, and washing that enable the separation (extractive metallurgy) of valuable metals or minerals from their Gangue (waste material). See Also: biomineralization ENVIRONMENTAL EFFECTS Environmental issues can include Erosion , formation of Sinkhole s, loss of Biodiversity , and contamination of Groundwater s and surface water by chemicals from the mining process and products. Modern mining companies in some countries are required to follow environmental and rehabilitation codes, ensuring the area mined is returned to close to its original state. In some countries with pristine environments, such as large parts of Australia , this is impossible despite the best intentions. Some mining methods have devastating environmental and public health effects. Mining can have adverse effects on surrounding surface and ground water if protection measures are not exercised. The result can be unnaturally high concentrations of some chemical elements, notably arsenic and sulfuric acid, over a significantly large area of surface or subsurface. Coal mining releases approximately twenty toxic chemicals, of which 85% is said to be managed on site. Combined with the effects of water and the new 'channels' created for water to travel through, collect in, and contact with these chemicals, a situation is created in which massive contamination can occur. In well-regulated mines, hydrologists and geologists take careful measures to mitigate any type of water contamination that could be caused by mines. In modern American mining, operations must, under federal and state law, meet standards for protecting surface and ground waters from contamination, including Acid Mine Drainage (AMD). To mitigate these problems water is continuously monitored at coal mines. The five principal technologies used to control water flow at mine sites are: diversion systems, containment ponds, groundwater pumping systems, subsurface drainage systems, and subsurface barriers. In the case of AMD, contaminated water is generally pumped to a treatment facility that neutralizes the contaminants. Some examples of environmental problems associated with mining operations are: : Ashio Copper Mine , Ashio , Japan was the site of substantial pollution at end of the Nineteenth Century : Acid Mine Drainage , exemplified by the cases of the Berkeley Lake Mine , and the ''' Wheal Jane Mine ''' :Dissolution and transport of dissolved metals and heavy metals by run-off and ground waters, an example being the Britannia Mine , a former copper mine near Vancouver, British Columbia. '''Tar Creek''', an abandoned mining area in Picher, Oklahoma that is now an Environmental Protection Agency Superfund site. Water in the mine has leaked through into local Groundwater , contaminating it with metals such as Lead and Cadmium . {Link without Title} :Long-term storage of tailings and dust, which can be easily blown off site by wind, an example being Scouriotissa, an abandoned copper mine in Cyprus . :Erosion of exposed hillsides, mine dumps, tailings dams and resultant Siltation of drainages, creeks and rivers, the prime example being the giant Ok Tedi Mine in Papua New Guinea . :In areas of wilderness mining may cause habitat destruction and destruction or disturbance of Ecosystems , and in areas of farming it may disturb or destroy productive grazing and cropping lands. In urbanised environments mining may produce Noise Pollution , dust pollution and visual pollution. Although such issues have been associated with some mining operations in the past, modern mining practices have improved significantly and are subject to close environmental scrutiny. Modern mining practises aim to lessen environmental impacts from mining, and the ultimate aim is to return the local environment to as close to pristine as is possible. In many cases, the most significant environmental impact longer-term is visual, with pits and mine dumps prominent landscape features. To ensure completion of Reclamation (restoring mine land) most governments and regulatory authorities around the world require that mining companies post a bond to be held in escrow until productivity of reclaimed land has been convincingly demonstrated. Since 1978 the mining industry has reclaimed more than 2 million acres (8,000 km&2) of land in the United States alone. This reclaimed land has renewed vegetation and wildlife in previous mining lands and can even be used for farming and ranching. For further reading on reclamation of former mining sites, see Restoration Ecology . MINING INDUSTRY Overview While exploration and mining can sometimes be conducted by individual entrepreneurs or small business, most modern-day mines are large enterprises requiring large amounts of capital to establish. Consequently, the mining sector of the industry is dominated by large, often multinational, mostly publicly-listed companies. See for a list. However, what is referred to as the 'mining industry' is actually two sectors, one specializing in exploration for new resources, the other specializing in mining those resources. The exploration sector is typically made up of individuals and small mineral resource companies dependent on public investment. The mining sector is typically large and multi-national companies sustained by mineral production from their mining operations. Employment United States Miners today do more than just dig tunnels in the Earth's subsurface. There are many different jobs, direct and indirect, in the mining industry, ranging from engineers and lab technicians to geologists and environmental specialists. Beyond employment directly linked to mine-site activity, the modern mining industry also employs many other professionals, including accountants, lawyers, sales representatives, public relations specialists, not to mention thousands of men and women involved who manufacture the machines and equipment necessary to mine minerals. Employment in the mining industry offers highly competitive wages and benefits, especially in rural or remote areas. According to the Bureau Of Labor Statistics (BLS), wages for coal miners are 30% higher than the wage earned by the average American. Employees possessing at least a bachelor's degree in mining or geological engineering can earn a median pay of over $80,000 annually. The US Bureau of Labor Statistics estimates that 675,000 are employed in the natural resources and mining sector. Estimated employment by selected specific commodity (including mine, mill, smelter, and quarry workers) listed below is from US Geological Survey Mineral Commodity Surveys :
The mining industry has an experienced but aging workforce with a mean average age of 50 years and median of 46 years. Indeed, while the industry will require new employees to meet future demand, the largest dilemma currently facing mine operators is finding employees to fill vacancies left by a generation of miners, mine engineers, senior managers, technical experts and others who are set to retire between 2005 and 2015. However, the industry is struggling to meet that demand due to current low enrollment levels in mining education programs at American colleges and universities. Mining is regulated under a comprehensive federal safety law (Federal Mine Safety and Health Act) that is administered by the Department of Labor's Mine Safety and Health Administration (MSHA). Currently under federal law, and enforced by MSHA each U.S. miner must have an approved worker training program in health and safety issues, including at least 40 hours of basic safety training for new underground miners with no experience; 24 hours for new miners at surface mines with no experience; plus eight hours of annual refresher training for all miners. SAFETY United states Safety has long been a controversial issue in the mining business especially with sub-surface mining. While mining today is substantially safer than it was in the previous decades, Mining Accident s are often very high profile tragedies, such as the Quecreek Mine Rescue saving 9 trapped Pennsylvania coal miners in 2002. Mining ventilation is often seen to be a safety concern for many miners and their families. Poor ventilation of the mines causes exposure to harmful gases, heat and dust inside sub-surface mines. These can cause harmful physiological effects, even death. Methane gas is a common source of ignition for explosions in coal mines and can propagate into the more violent coal dust explosions. High temperatures and humidity may result in heat-related illnesses, including heat stroke which can be fatal. Dusts can cause lung problems, including Silicosis , Asbestosis and Pneumoconiosis (also known as miners lung or Black Lung disease). A ventilation system is set up to course a stream of air through the working areas of the mine. The air circulation necessary for the effective ventilation of a mine is generated by one or more large mine fans, usually located above ground. In the United States, the main fans at coal mines are required to be above ground. Air flows in one direction only, making circuits through the mine such that each main work area receives a supply of fresh air. Mining is regulated under the federal Mine Safety And Health Act by MSHA, which employs nearly one safety inspector for every four coal mines. Underground coal mines are thoroughly inspected at least four times annually by MSHA inspectors. In addition, miners can report violations, request additional inspections. Miners with such concerns for their work safety cannot be penalized with any threat to the loss of employment. The National Institute for Occupational Safety and Health (NIOSH) , part of the Centers for Disease Control and Prevention under the U.S. Department of Health and Human Services , conducts mining safety and health research, with the aim to eliminate mining fatalities, injuries, and illnesses through research and prevention. Immediately reportable accidents and injuries are: # A death of an individual at a mine; # An injury to an individual at a mine which has a reasonable potential to cause death; # An entrapment of an individual for more than thirty minutes; # An unplanned inundation of a mine by a liquid or gas; # An unplanned ignition or explosion of gas or dust; # An unplanned mine fire not extinguished within 30 minutes of discovery; # An unplanned ignition or explosion of a blasting agent or an explosive; # An unplanned roof fall at or above the anchorage zone in active workings where roof bolts are in use; or, an unplanned roof or rib fall in active workings that impairs ventilation or impedes passage; # A coal or rock outburst that causes withdrawal of miners or which disrupts regular mining activity for more than one hour; # An unstable condition at an impoundment, refuse pile, or culm bank which requires emergency action in order to prevent failure, or which causes individuals to evacuate an area; or, failure of an impoundment, refuse pile, or culm bank; # Damage to hoisting equipment in a shaft or slope which endangers an individual or which interferes with use of the equipment for more than thirty minutes; and # An event at a mine which causes death or bodily injury to an individual not at the mine at the time the event occurs. Statistical analyses performed by the U.S. Department Of Labor 's Mine Safety And Health Administration (MSHA) show that between 1990 and 2004, the industry cut the rate of injuries (a measure comparing the rate of incidents to overall number of employees or hours worked) by more than half and fatalities by two-thirds following three prior decades of steady improvement. MACHINERY Heavy machinery is needed in mining to break and remove rocks of diverse hardness and toughness. Bulldozers, drills, explosives and trucks are important for digging into the land, especially in surface mining. Underground mining, like continuous mining, tends to be more technologically sophisticated because of the dangers and expense of subsurface tunneling. Tram s are used to transport miners, minerals and waste. Mining machinery manufacturers include Joy Mining Machinery , Bucyrus International , Caterpillar , Komatsu , Volvo , Hitachi , Terex , Dresser Industries , Kawasaki , Eimco Elecon India Limited , and Liebherr . Placer Mining is a type of surface mining, usually for Gold , tin, and other metals, and gemstones. Ore, typically unconsolidated gravels, is fed into machinery that may consist of a hopper, shaking screen or Trommel which frees the minerals from the gravels. The target minerals are then concentrated using Sluices or jigs. ABANDONED MINES The number of abandoned mines in the s. Experts strongly warn against entering or exploring old or abandoned mines. In the U.S., the estimation is that approximately 25% of the abandoned mine lands (AML) sites pose physical safety hazards. Greenley, M.N. (1999). National Reclamation of Abandoned Mine Lands. Presentation to the Society for Mining Metallurgy and Exploration: Author. Retrieved Aug. 27, 2007, {Link without Title} Old mines are often dangerous and can contain deadly gases, Snake s, and other dangerous animals. Since weather may have Eroded the earth/rock surrounding it, the entrance to an old mine in particular can be very dangerous. Old mine workings, caves, etc. are commonly hazardous simply due to the lack of oxygen in the air (a condition in mines known as Blackdamp ). Blackdamp is a deadly killer which provides no warning to any individual or group of individuals entering such an environment. Every year, dozens are injured or killed in recreational accidents on mine property. It is only fair to note, however, that the majority of the deaths are unrelated to mine exploration. Drownings in open quarries and ATV accidents on abandoned mine properties are the main cause of accidental death. The U.S. Department of Labor notes that since 1999, "more than 200 people have died in recreational accidents at surface and underground active and abandoned operations across the country." U.S. Department of Labor, (March, 2007). MSHA issues warning to children and adults to 'Stay Out and Stay Alive'. News Release: Author. Retrieved Aug. 27, 2007, {Link without Title} Due to these circumstances, MSHA ( Mine Safety And Health Administration ) launched the "Stay Out – Stay Alive" campaign, which is a national public awareness campaign aimed at warning and educating children and adults about the dangers of exploring and playing on active and abandoned mine sites. In the U.S., the Abandoned Mine Land Initiative, launched by the Western Governor's Association and the (UNEP) and the Chilean Copper Commission (COHILCO) co-hosted a workshop to address the problem of abandoned or "orphaned" mines. Chilean Copper Commission (COHILCO) and United Nations Environment Program: Division of Technology, Industry and Economics, (June, 2001). Abandoned Mines: Problems, Issues and Policy Challenges for Decision Makers. Summary Report: Author. Retrieved Aug. 27, 2007, {Link without Title} Including a representative from the UN, ten countries were represented from North, Central and South America with an eleventh participant being Japan. RECORDS
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