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43-655: Phoenix Mine was an open pit and underground mining operation in city of Phoenix in the Boundary Country region of British Columbia , Canada that operated in the early and mid 20th century, run by the Granby Consolidated Mining, Smelting and Power Company . It was discovered in 1891, but was a lower grade copper deposit than the Rossland and Slocan deposits. The low grade and the nearest railroad being 75 miles (121 km) resulted in

86-463: A concentration high enough to have significant negative impacts. A pollutant may cause long- or short-term damage by changing the growth rate of plant or animal species, or by interfering with resources used by humans, human health or wellbeing, or property values. Some pollutants are biodegradable and therefore will not persist in the environment in the long term. However, the degradation products of some pollutants are themselves polluting such as

129-447: A mine that contribute to this load: drilling , blasting, loading, and hauling . Waste rock is hauled to a waste dump. Waste dumps can be piled at the surface of the active pit, or in previously mined pits. Leftover waste from processing the ore is called tailings , and is generally in the form of a slurry . This is pumped to a tailings dam or settling pond, where the water is reused or evaporated. Tailings dams can be toxic due to

172-692: A mining company interested in operating it. In 1896 development of the deposit began and in 1900 the Granby Smelter Company constructed a 700-ton-per-day smelter in Grand Forks, British Columbia , which would be the largest non-ferrous smelter in the British Empire , and the second largest in the world. Granby operated the Phoenix mine, which comprised both an underground mine and open pit mine . The underground operation used

215-429: A number of worked-out mines. After mining ends at a location, the mine area may undergo land rehabilitation . Waste dumps are contoured to flatten them out, to further stabilize them. If the ore contains sulfides it is usually covered with a layer of clay to prevent ingress of rain and oxygen from the air, which can oxidize the sulfides to produce sulfuric acid , a phenomenon known as acid mine drainage . This

258-477: A result of room and pillar mining . Untopping removes the overburden from above this, opens up the mine from above, and then allows the previously 'trapped' minerals to be won. Untopping was a feature of Welsh slate workings in the 1930s and 2000s, where Martyn Williams-Ellis, manager at Llechwedd found that earlier Victorian workings could be kept profitable with the newly mechanised techniques for bulk excavation to extract their pillars, and more recently across

301-450: Is a crucial aspect of determining whether or not a geotechnical engineering design for open-pit slopes is attainable. Groundwater control systems, which include dewatering and depressurization wells, may also have a large impact on local groundwater. Because of this, an optimization-based version of the control system is required to ensure that local and regional hydro-geological impacts are within acceptable ranges. Open Pit depressurization

344-440: Is an international legally binding agreement for the control of persistent organic pollutants. Pollutant Release and Transfer Registers (PRTR) are systems to collect and disseminate information on environmental releases and transfers of toxic chemicals from industrial and other facilities. The European Pollutant Emission Register is a type of PRTR providing access to information on the annual emissions of industrial facilities in

387-513: Is continually synthesizing new chemicals, the regulation of which requires evaluation of the potential danger for human health and the environment . Risk assessment is nowadays considered essential for making these decisions on a scientifically sound basis. Measures or defined limits include: Pollutants can cross international borders and therefore international regulations are needed for their control. The Stockholm Convention on Persistent Organic Pollutants , which entered into force in 2004,

430-509: Is determined by the size of the equipment being used, generally 20–40 metres wide. Downward ramps are created to allow mining on a new level to begin. This new level will become progressively wider to form the new pit bottom. Most walls of the pit are generally mined on an angle less than vertical. Waste rock is stripped when the pit becomes deeper, therefore this angle is a safety precaution to prevent and minimize damage and danger from rock falls. However, this depends on how weathered and eroded

473-401: Is the process of removing tensions or pressure from different areas of a mine. Depressurization helps to make open-pit mines more stable and secure. By using an integrated mine slope depressurization program the likelihood that mine plans can be achieved, and at an acceptable level of risk increase drastically. Depressurization allows considerable expansions of a mine, and can extend the life of

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516-559: Is then generally covered with soil , and vegetation is planted to help consolidate the material. Eventually this layer will erode, but it is generally hoped that the rate of leaching or acid will be slowed by the cover such that the environment can handle the load of acid and associated heavy metals. There are no long term studies on the success of these covers due to the relatively short time in which large-scale open-pit mining has existed. It may take hundreds to thousands of years for some waste dumps to become "acid neutral" and stop leaching to

559-610: Is to group them together according to more specific properties, such as organic, particulate, pharmaceutical, et cetera. The environment has some capacity to absorb many discharges without measurable harm, and this is called “ assimilative capacity (or absorptive capacity); a pollutant actually causes pollution when the assimilative capacity is exceeded. Pollutants, towards which the environment has low absorptive capacity are called stock pollutants . Examples include persistent organic pollutants like PCBs , non- biodegradable plastics and heavy metals . Stock pollutants accumulate in

602-724: The Clean Water Act , EPA promulgated national standards for municipal sewage treatment plants, also called publicly owned treatment works , in the Secondary Treatment Regulation. National standards for industrial dischargers are called Effluent guidelines (for existing sources) and New Source Performance Standards , and currently cover over 50 industrial categories. In addition, the Act requires states to publish water quality standards for individual water bodies to provide additional protection where

645-668: The Lusatian Lake District , the Central German Lake District or the Upper Palatinate Lake District. A particular concern in the formation of these lakes is acid mine drainage . Open-pit mines create a significant amount of waste. Almost one million tons of ore and waste rock can move from the largest mines per day, and a couple thousand tons moved from small mines per day. There are generally four main operations in

688-594: The Philippines and Indonesia . In 2024, nickel mining and processing was one of the main causes of deforestation in Indonesia . Open-pit cobalt mining has led to deforestation and habitat destruction in the Democratic Republic of Congo . Open-pit mines operating in an area with heavy groundwater features may eventually face hydrology-related problems. This includes heaving and bursting of

731-418: The mineral resource is exhausted, or an increasing ratio of overburden to ore makes further mining uneconomic. After open-pit mines are closed, they are sometimes converted to landfills for disposal of solid waste. Some form of water control is usually required to keep the mine pit from becoming a lake. Several former open-pit mines have been deliberately converted into artificial lakes, forming areas such as

774-401: The square set mining method, but by 1901 had converted to an open stope and pillar method with considerable cost savings. The operation maintained a completely unsupported "show stope" with dimensions of 80 feet (24 m) high, 105 feet (32 m) wide, and 400 feet (122 m) long. In 1903 the mine operated three small steam shovels to work in the surface operations producing half of

817-967: The Member States of the European Union , as well as Norway. Clean Air Act standards. Under the Clean Air Act , the National Ambient Air Quality Standards (NAAQS) are developed by the Environmental Protection Agency (EPA) for six common air pollutants, also called "criteria pollutants": particulates ; smog and ground-level ozone ; carbon monoxide ; sulfur oxides ; nitrogen oxides ; and lead . The National Emissions Standards for Hazardous Air Pollutants are additional emission standards that are set by EPA for toxic air pollutants. Clean Water Act standards. Under

860-497: The Miner-Graves Syndicate. In 1899, they incorporated The Granby Consolidated Mining and Smelting Company, Limited and, in 1901, consolidated as Granby Consolidated Mining, Smelting and Power Company, Limited . In spite of the low grade of the ore from the Phoenix deposit, it had the advantage of being self-fluxing (only requiring coke to be added for smelting), which resulted in a cheaper processing cost for

903-467: The Phoenix (and other new deposits) receiving less attention. The first claims in the Phoenix area were staked by Henry White and Matthew Hatter (of the Old Ironsides claim) on July 15, 1891, they were granted in 1896. In 1896, J.F.C. Miner , a rubber footwear manufacturer from Granby, Quebec , mining promoter J.P. Graves of Knob Hill Mining Company and A.L. Little of Old Ironsides formed

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946-550: The area that is damaged by a pollutant. Local pollutants cause damage near the emission source. Regional pollutants cause damage further from the emission source. The vertical zone refers to whether the damage is ground-level or atmospheric. Surface pollutants cause damage by accumulating near the Earth's surface. Global pollutants cause damage by concentrating on the [atmosphere]. Measures of pollutant concentration are used to determine risk assessment in public health . Industry

989-402: The areas surrounding open-pit mines. Open-pit gold mining is one of the highest potential mining threats on the environment as it affects the air and water chemistry. The exposed dust may be toxic or radioactive, making it a health concern for the workers and the surrounding communities. Open-pit nickel mining has led to environmental degradation and pollution in developing countries such as

1032-500: The environment has low absorptive capacity, fund pollutants are those for which the environment has a moderate absorptive capacity. Fund pollutants do not cause damage to the environment unless the emission rate exceeds the receiving environment's absorptive capacity (e.g. carbon dioxide, which is absorbed by plants and oceans). Fund pollutants are not destroyed, but rather converted into less harmful substances, or diluted/dispersed to non-harmful concentrations. Many pollutants are within

1075-498: The environment over time. The damage they cause increases as more pollutant is emitted, and persists as the pollutant accumulates. Stock pollutants can create a burden for the future generations , bypassing on the damage that persists well after the benefits received from incurring that damage, have been forgotten. Scientists have officially deemed that the planetary boundaries safe chemical pollutant levels (novel entities) have been surpassed. In contrast to stock pollutants, for which

1118-472: The environment. The dumps are usually fenced off to prevent livestock denuding them of vegetation. The open pit is then surrounded with a fence , to prevent access, and it generally eventually fills up with ground water . In arid areas it may not fill due to deep groundwater levels. In Germany, the world's largest producer of lignite (virtually all of which these days is mined open-pit), the former mines are usually converted to artificial lakes . To mitigate

1161-432: The following notable groups: Light pollution is the impact that anthropogenic light has on the visibility of the night sky. It also encompasses ecological light pollution which describes the effect of artificial light on individual organisms and on the structure of ecosystems as a whole. Pollutants can also be defined by their zones of influence, both horizontally and vertically. The horizontal zone refers to

1204-429: The hole. The interval of the benches depends on the deposit being mined, the mineral being mined, and the size of the machinery that is being used. Generally, large mine benches are 12 to 15 metres thick. In contrast, many quarries do not use benches, as they are usually shallow. Mining can be conducted on more than one bench at a time, and access to different benches is done with a system of ramps. The width of each bench

1247-454: The mine by 10 to 15 years. One technique used in depressurization is annealing. Annealing is the slow heating and cooling of a metal, alloy or glass. This slow heating and cooling relieves the internal stress of surrounding areas. Annealing will increase a material's workability and durability, which overall increases open-pit mine safety. When groundwater pressures cause problems in open-pit mines, horizontal drains are used to aid in accelerating

1290-450: The mine floor due to excessive uplift pressure. A groundwater control system must be installed to fix problems caused by hydrology. The formation of an appropriate open-pit slope design, changes throughout the life of a mine. It is based mainly on an ever-increasing understanding of the rock mass conditions, including groundwater and associated pressures that may be acting within the slopes. The reduction of groundwater related to pore pressures

1333-543: The mine's production, making this one of the earliest attempts at open-pit mining in the British Columbia. Ore was transported to the smelter via the Canadian Pacific Railway , which had built a line to the mining operation by the time the smelter was completed in 1900. In 1956 Granby re-evaluated the property in light of recent success in their other open-pit operations in the province. There

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1376-446: The presence of unextracted sulfide minerals , some forms of toxic minerals in the gangue , and often cyanide which is used to treat gold ore via the cyanide leach process . If proper environmental protections are not in place, this toxicity can harm the surrounding environment. Open-pit mining involves the process of disrupting the ground, which leads to the creation of air pollutants. The main source of air pollutants comes from

1419-407: The problem of acid mine drainage mentioned above, flooding is often done with the water of nearby rivers instead of using groundwater alone. In some cases, calcium oxide or other basic chemicals have to be added to the water to neutralize the pH -value. Gold is generally extracted in open-pit mines at 1 to 5 ppm (parts per million) but in certain cases, 0.75 ppm gold is economical. This

1462-445: The products DDE and DDD produced from the degradation of DDT . Pollution has widespread negative impacts on the environment. When analyzed from a planetary boundaries perspective, human society has released novel entities that well exceed safe levels. Pollutants can be categorized in a variety of different ways. For example, it is sometimes useful to distinguish between stock pollutants and fund pollutants . Another way

1505-404: The rocks are, and the type of rocks involved. It also depends on the amount of structural weaknesses occur within the rocks, such as a faults , shears , joints or foliations . The walls are stepped. The inclined section of the wall is known as the batter, and the flat part of the step is known as the bench or berm. The steps in the walls help prevent rock falls continuing down the entire face of

1548-412: The slope depressurization process. Which helps to prevent large scale slope failure in the mine. Horizontal drains are used to lower pore pressure by reducing groundwater head, which enhances slope stability. A form of open-cast quarrying may be carried out as 'untopping'. This is done where a previous underground mine is becoming uneconomic or worked-out, but still leaves valuable rock in place, often as

1591-558: The surface where the overburden is relatively thin. In contrast, deeper mineral deposits can be reached using underground mining. Open-pit mining is considered one of the most dangerous sectors in the industrial world . It causes significant effects to miners' health, as well as damage to the ecological land and water. Open-pit mining causes changes to vegetation, soil, and bedrock, which ultimately contributes to changes in surface hydrology, groundwater levels, and flow paths. Additionally, open-pit produces harmful pollutants depending on

1634-416: The transportation of minerals, but there are various other factors including drilling, blasting and the loading and unloading of overburden. These type of pollutants cause significant damage to public health and safety in addition to damaging the air quality. The inhalation of these pollutants can cause issues to the lungs and ultimately increase mortality. Furthermore, the pollutants affect flora and fauna in

1677-517: The type of mineral being mined, and the type of mining process being used. Miners typically drill a series of test holes to locate an underground ore body. From the extracted samples, they can determine the extent of the ore. This helps them determine the likely location of the veins or benches of ore and its commercial value. Open-pit mines that produce building materials and dimension stone are commonly referred to as quarries . Open-cast mines are dug on benches , which describe vertical levels of

1720-466: The wall. In some instances additional ground support is required and rock bolts , cable bolts and shotcrete are used. De-watering bores may be used to relieve water pressure by drilling horizontally into the wall, which is often enough to cause failures in the wall by itself. A haul road is usually situated at the side of the pit, forming a ramp up which trucks can drive, carrying ore and waste rock. Open-pit mines are typically worked until either

1763-519: The world. Listed are the world's ten largest open-pit mines in 2015. Pollutant A pollutant or novel entity is a substance or energy introduced into the environment that has undesired effects, or adversely affects the usefulness of a resource. These can be both naturally forming (i.e. minerals or extracted compounds like oil ) or anthropogenic in origin (i.e. manufactured materials or byproducts ). Pollutants result in environmental pollution or become public health concerns when they reach

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1806-472: Was achieved by bulk heap leaching at the Peak Hill mine in western New South Wales , near Dubbo , Australia . Nickel , generally as laterite, is extracted via open-pit down to 0.2%. Copper can be extracted at grades as low as 0.11% to 0.2%. Open-pit mining is a common method to extract minerals and samples from the Earth. Due to being cost-effective, this method is very popular and is used all over

1849-453: Was an estimated 1,300,000 tons of ore readily available; a 600-ton-per-day concentrator was constructed and production began in 1959. The following year, when more ore per day became available, the concentrator was upgraded to handle 900 tons per day, 1,900 tons per day in 1964 and 2,750 in 1972 The Phoenix mine closed again in 1976. Open-pit mining Open-pit mines are used when deposits of commercially useful ore or rocks are found near

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