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75-496: A secret town during the Soviet Union because of the uranium mine present, these days no uranium is mined anymore and the town is known as a summer holiday resort for locals from Tashkent. A couple of kilometers from the town there is a mineral water spring which is mainstream in the town and different urban areas. In 2021 preparations for the environmental remediation at the former mine, and also at Charkesar , started with

150-504: A functional group ( amidoxime group ) that selectively adsorbs heavy metals, and the performance of such adsorbents has been improved. Uranium adsorption capacity of the polymer fiber adsorbent is high, approximately tenfold greater in comparison to the conventional titanium oxide adsorbent. One method of extracting uranium from seawater is using a uranium-specific nonwoven fabric as an adsorbent. The total amount of uranium recovered from three collection boxes containing 350 kg of fabric

225-519: A large cask, or tun . A full tun, standing about a metre high, could easily weigh a tonne. See also the common German word de:Mülltonne (literal translation: garbage drum ). The spelling tonne pre-dates the introduction of the SI in 1960; it has been used with this meaning in France since 1842, when there were no metric prefixes for multiples of 10 and above, and is now used as the standard spelling for

300-605: A lesser extent to a long ton of 2,240 lb (1,016 kg), with the term tonne rarely used in speech or writing. Both terms are acceptable in Canadian English . Ton and tonne are both derived from a Germanic word in general use in the North Sea area since the Middle Ages (cf. Old English and Old Frisian tunne , Old High German and Medieval Latin tunna , German and French tonne ) to designate

375-436: A method of extraction that does not produce the same occupational hazards, or mine tailings, as conventional mining. With regulations in place to ensure the use of high volume ventilation technology if any confined space uranium mining is occurring, occupational exposure and mining deaths can be largely eliminated. The Olympic Dam and Canadian underground mines are ventilated with powerful fans with radon levels being kept at

450-455: A sandstone body. Peneconcordant sandstone uranium deposits, also called Colorado Plateau –type deposits, most often occur within generally oxidized sandstone bodies, often in localized reduced zones, such as in association with carbonized wood in the sandstone. Precambrian quartz-pebble conglomerate-type uranium deposits occur only in rocks older than two billion years old. The conglomerates also contain pyrite. These deposits have been mined in

525-467: A very low to practically "safe level" in uranium mines. Naturally occurring radon in other, non-uranium mines, also may need control by ventilation. Heap leaching is an extraction process by which chemicals (usually sulfuric acid ) are used to extract the economic element from ore which has been mined and placed in piles on the surface. Heap leaching is generally economically feasible only for oxide ore deposits. Oxidation of sulfide deposits occurs during

600-482: Is a non-SI unit accepted for use with SI . It is also referred to as a metric ton in the United States to distinguish it from the non-metric units of the short ton ( United States customary units ) and the long ton ( British imperial units ). It is equivalent to approximately 2,204.6 pounds , 1.102 short tons, and 0.984 long tons. The official SI unit is the megagram ( Mg ), a less common way to express

675-419: Is also less radioactive due to a lower content of short-lived U and U than natural uranium. Uranium is mined by in-situ leaching (57% of world production) or by conventional underground or open-pit mining of ores (43% of production). During in-situ mining, a leaching solution is pumped down drill holes into the uranium ore deposit where it dissolves the ore minerals. The uranium-rich fluid

750-459: Is concluded. Land reclamation after mining takes different routes, depending on the amount of material removed. Due to the high energy density of uranium, it is often sufficient to fill in the former mine with the overburden, but in case of a mass deficit exceeding the height difference between the previous surface level and the natural water table, artificial lakes develop when groundwater removal ceases. If sulfites, sulfides or sulfates are present in

825-435: Is extensively used to suppress airborne dust levels. Groundwater is an issue in all types of mining, but in open pit mining, the usual way of dealing with it – i.e. when the target mineral is found below the natural water table – is to lower the water table by pumping off the water. The ground may settle considerably when groundwater is removed and may again move unpredictably when groundwater is allowed to rise again after mining

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900-453: Is home to approximately 500 mineralized breccia pipes and Cripple Creek, Colorado, also is a site that contains breccia pipe ore deposits that is associated with a volcanic pipe. Olympic Dam mine , the world's largest uranium deposit, was discovered by Western Mining Corporation in 1975 and is owned by BHP . Uranium prospecting is similar to other forms of mineral exploration with the exception of some specialized instruments for detecting

975-399: Is in principle no different from any other hard rock mining and other ores are often mined in association (e.g., copper, gold, silver). Once the ore body has been identified a shaft is sunk in the vicinity of the ore veins, and crosscuts are driven horizontally to the veins at various levels, usually every 100 to 150 metres. Similar tunnels, known as drifts, are driven along the ore veins from

1050-438: Is little need to distinguish between metric and other tons, and the unit is spelled either as ton or tonne with the relevant prefix attached. A metric ton unit (mtu) can mean 10 kg (22 lb) within metal trading, particularly within the United States. It traditionally referred to a metric ton of ore containing 1% (i.e. 10 kg) of metal. The following excerpt from a mining geology textbook describes its usage in

1125-432: Is now the accepted leading technique for uranium prospecting with worldwide applications for geological mapping, mineral exploration & environmental monitoring . Airborne gamma-ray spectrometry used specifically for uranium measurement and prospecting must account for a number of factors like the distance between the source and the detector and the scattering of radiation through the minerals, surrounding earth and even in

1200-441: Is practically limitless with respect to world-wide demand. That is to say, if even a portion of the uranium in seawater could be used the entire world's nuclear power generation fuel could be provided over a long time period. Some proponents claim this statistic is exaggerated. Although research and development for recovery of this low-concentration element by inorganic adsorbents such as titanium oxide compounds has occurred since

1275-400: Is the joule . One tonne of TNT is approximately equivalent to 4.2 gigajoules. In the petroleum industry the tonne of oil equivalent (toe) is a unit of energy : the amount of energy released by burning one tonne of crude oil , approximately 42 GJ. There are several slightly different definitions. This is ten times as much as a tonne of TNT because atmospheric oxygen is used. Like

1350-481: Is the mass of one cubic metre of pure water at 4 °C (39 °F). As a non-SI unit, the use of SI metric prefixes with the tonne does not fall within the SI standard. For multiples of the tonne, it is more usual to speak of thousands or millions of tonnes. Kilotonne, megatonne, and gigatonne are more usually used for the energy of nuclear explosions and other events in equivalent mass of TNT , often loosely as approximate figures. When used in this context, there

1425-413: Is then pumped back to the surface and processed to extract the uranium compounds from solution. In conventional mining, ores are processed by grinding the ore materials to a uniform particle size and then treating the ore to extract the uranium by chemical leaching . The milling process commonly yields dry powder-form material consisting of natural uranium, " yellowcake ", which is nowadays commonly sold on

1500-466: Is used as a proxy for energy, usually of explosions (TNT is a common high explosive ). Prefixes are used: kiloton(ne), megaton(ne), gigaton(ne), especially for expressing nuclear weapon yield , based on a specific combustion energy of TNT of about 4.2  MJ / kg (or one thermochemical calorie per milligram ). Hence, 1 t TNT = approx. 4.2  GJ , 1 kt TNT = approx. 4.2  TJ , 1 Mt TNT = approx. 4.2  PJ . The SI unit of energy

1575-434: Is used for thinner, flatter ore bodies. In this method the ore body is first divided into blocks by intersecting drives, removing ore while so doing, and then systematically removing the blocks, leaving enough ore for roof support. The health effects discovered from radon exposure in unventilated uranium mining prompted the switch away from uranium mining via tunnel mining towards open cut and in-situ leaching technology,

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1650-413: Is usually pronounced the same as ton ( / t ʌ n / ), but the final "e" can also be pronounced, i.e. " tunnie " ( / ˈ t ʌ n i / ). In Australia, the common and recommended pronunciation is / t ɒ n / . In the United States, metric ton is the name for this unit used and recommended by NIST; an unqualified mention of a ton typically refers to a short ton of 2,000 lb (907.2 kg) and to

1725-691: The Blind River – Elliot Lake district of Ontario, Canada, and from the gold-bearing Witwatersrand conglomerates of South Africa. Unconformity-type deposits make up about 33% of the World Outside Centrally Planned Economies Areas' (WOCA) uranium deposits. Hydrothermal uranium deposits encompass the vein-type uranium ores. Vein-type hydrothermal uranium deposits represent epigenetic concentrations of uranium minerals that typically fill breccias, fractures, and shear zones. Many studies have sought to identify

1800-1334: The Elkon mine at 71,300 tU, the Brazilian Itataia complex at 67,240 tU, the Marenica project at 62,856 tU, the Langer Heinrich Mine at 60,830 tU, the Dominion mine at 55,753 tU, the Inkai Uranium Project at 51,808 tU, the Kiggavik project at 51,574 tU, the Rössing mine at 50,657 tU, the Australian Yeleerie project at 44,077, and the Trekkopje mine at 42,243 tU. Many different types of uranium deposits have been discovered and mined. There are mainly three types of uranium deposits including unconformity-type deposits, namely paleoplacer deposits and sandstone-type, also known as roll front type deposits. Uranium deposits are classified into 15 categories according to their geological setting and

1875-1114: The Olympic Dam mine at 2981 tU, the Arlit mine at 1808 tU, the Rabbit Lake mine at 1400 tU, the Akouta mine at 1435 tU, and the McClean Lake mine at 1400 tU. The world's largest deposits include the Olympic Dam mine at 295,000 tU, the Imouraren mine at 183,520 tU, the McArthur River mine at 128,900 tU, the Streltsovsk mine at 118,341 tU, the Novokonstantinovka mines at 93,630, the Cigar Lake Mine at 80,500 tU, Uzbekistan mines at 76,000 tU,

1950-472: The western US ), Precambrian unconformities (in Canada), phosphate , Precambrian quartz -pebble conglomerate , collapse breccia pipes (see Arizona breccia pipe uranium mineralization ), and calcrete . Sandstone uranium deposits are generally of two types. Roll-front type deposits occur at the boundary between the up dip and oxidized part of a sandstone body and the deeper down dip reduced part of

2025-400: The "cut and fill" or "open stoping" method, the space remaining following removal of ore after blasting is filled with waste rock and cement. In the "shrinkage" method, only sufficient broken ore is removed via the chutes below to allow miners working from the top of the pile to drill and blast the next layer to be broken off, eventually leaving a large hole. The method known as "room and pillar"

2100-696: The 1960s in the United Kingdom, France, Germany, and Japan, this research was halted due to low recovery efficiency. At the Takasaki Radiation Chemistry Research Establishment of the Japan Atomic Energy Research Institute (JAERI Takasaki Research Establishment), research and development has continued culminating in the production of adsorbent by irradiation of polymer fiber. Adsorbents have been synthesized that have

2175-536: The GSC built a lighter weight, more practical unit in 1934. Subsequent models were the principal instruments used for uranium prospecting for many years, until geiger counters were replaced by scintillation counters . The use of airborne detectors to prospect for radioactive minerals was first proposed by G. C. Ridland, a geophysicist working at Port Radium in 1943. In 1947, the earliest recorded trial of airborne radiation detectors (ionization chambers and Geiger counters)

2250-461: The May, 2008 exchange rate, this was about $ 240/kg-U. In 2012, ORNL researchers announced the successful development of a new adsorbent material dubbed "HiCap", which vastly outperforms previous best adsorbents, which perform surface retention of solid or gas molecules, atoms or ions. "We have shown that our adsorbents can extract five to seven times more uranium at uptake rates seven times faster than

2325-424: The SI symbols for the tesla , megatesla, and millitesla, respectively, while Mt and mt are SI-compatible symbols for the megatonne (one teragram) and millitonne (one kilogram). If describing TNT equivalent units of energy, one megatonne of TNT is equivalent to approximately 4.184 petajoules . In English, tonne is an established spelling alternative to metric ton . In the United States and United Kingdom, tonne

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2400-524: The Sengier reopened the Sinkolobwe mine with U.S. Army Corps of Engineers ' resources, and a $ 13 million investment from the United States. Sengier reported that uranium ore had been extracted from the mine down to a depth of 79 meters, but that another 101 meters of ore was available for extraction. This amounted to 10,000 tons of up to 60% triuranium octoxide . The project also acquired most of

2475-679: The Shinkolobwe mine, but closed down in the late 1930s as the radium market diminished. In May 1940, the Nazis invaded Belgium and seized Union Minière's uranium ore stored there. On 18 September 1942, 1250 t of Shinkolobwe uranium ore for the Manhattan Project was purchased from Union Minière's Edgar Sengier , who had stockpiled the ore in an Archer Daniels Midland warehouse near the Bayonne Bridge , Staten Island . In 1943,

2550-845: The Soviet Republics of Kazakhstan and the RSFSR would later become some of the leading uranium producers in the world, immediately after the end of World War II the availability of large uranium deposits in the USSR wasn't yet known and thus the Soviets developed immense mining operations in their satellite states East Germany and Czechoslovakia which had known uranium deposits in the Ore Mountains. The deliberately opaquely named SDAG Wismut (the German term "Wismut" for Bismuth should give

2625-423: The United States. A large mass of breccia is called a breccia pipe or chimney and is composed of the rock forming an irregular and almost cylinder-like shape. The origin of breccia pipe is uncertain but it is thought that they form on intersections and faults.  When the formations are found solid in ground host rock called rock flour, it usually is often a site for copper or uranium mining. Copper Creek, Arizona,

2700-399: The advances made in the efficiency of seawater uranium extraction, it was suggested that it would be economically competitive to produce fuel for light water reactors from seawater if the process was implemented at large scale. Uranium extracted on an industrial scale from seawater would constantly be replenished by both river erosion of rocks and the natural process of uranium dissolved from

2775-500: The air. In Australia, a Weathering Intensity Index has been developed to help prospectors based on the Shuttle Radar Topography Mission (SRTM) elevation and airborne gamma-ray spectrometry images. A deposit of uranium, discovered by geophysical techniques, is evaluated and sampled to determine the amounts of uranium materials that are extractable at specified costs from the deposit. Uranium reserves are

2850-436: The amounts of ore that are estimated to be recoverable at stated costs. As prices rise or technology allows for lower cost of recovery of known, previously uneconomic, deposits, reserves increase. For uranium this effect is particularly pronounced as the biggest currently uneconomic reserve – uranium extraction from seawater – is bigger than all known land based resources of uranium combined. From 2008 through at least 2024,

2925-515: The application. Enrichment requires conversion of the yellowcake into uranium hexafluoride and production of the fuel (again usually uranium dioxide, but sometimes uranium carbide , uranium hydride or uranium nitride ) from that feedstock. Before 1789, when Martin Heinrich Klaproth discovered the element, uranium compounds produced included nitrate, sulfate, phosphate, acetate and potassium- and sodium- diuranate . Klaproth detected

3000-606: The arduous task of rehabilitating the land impacted by mining was begun. The seventeen towns and mines under Wismut's control contributed 50 percent of the uranium used in the Soviet's first atomic bomb, Joe-1 , and 80 percent of the uranium used in the Soviet nuclear program. Of the 150,000 laborers, 1281 were killed in accidents and 20,000 suffered injuries. After Stalin's death in 1953, the Red Army turned over control of production to SDAG, and prison laborers were released, reducing

3075-675: The assistance of a €2 million grant from the European Bank for Reconstruction and Development . This Uzbekistan location article is a stub . You can help Misplaced Pages by expanding it . Uranium mine Uranium mining is the process of extraction of uranium ore from the ground. Over 50,000 tons of uranium were produced in 2019. Kazakhstan, Canada, and Australia were the top three uranium producers, respectively, and together account for 68% of world production. Other countries producing more than 1,000 tons per year included Namibia, Niger, Russia, Uzbekistan and China. Nearly all of

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3150-421: The crosscut. To extract the ore, the next step is to drive tunnels, known as raises when driven upwards and winzes when driven downward, through the deposit from level to level. Raises are subsequently used to develop the stopes where the ore is mined from the veins. The stope, which is the workshop of the mine, is the excavation from which the ore is extracted. Three methods of stope mining are commonly used. In

3225-698: The disseminated uranium deposit at Rossing , Namibia; uranium-bearing pegmatites , and the Aurora crater lake deposit of the McDermitt Caldera in Oregon. Disseminated deposits are also found in the states of Washington and Alaska in the US. Breccia uranium deposits are found in rocks that have been broken due to tectonic fracturing, or weathering. Breccia uranium deposits are most common in India, Australia and

3300-520: The element radium . Pierre advocated its usage as a cancer cure, which fostered a spa business for that town. In 1913, the Shinkolobwe , Katanga Province, was discovered. In 1931, the Port Radium deposit was discovered. Other significant discoveries included Beira Province , Tyuya Muyun , and Radium Hill . In 1922, Union Minière du Haut Katanga started producing medicinal radium from

3375-630: The element in pitchblende from the George Wagsfort mine, Ore Mountains , and established commercial use as glass coloring. Pitchblende from these mountains was mentioned as early as 1565, and 110 t of uranium was produced from 1825 until 1898. In 1852, the uranium mineral autunite from the Massif Central was identified. Around 1850, uranium mining began in Joachimsthal, Bohemia , where more than 620 t of uranium metal (tU)

3450-500: The geological process called weathering. Therefore, oxide ore deposits are typically found close to the surface. If there are no other economic elements within the ore a mine might choose to extract the uranium using a leaching agent, usually a low molar sulfuric acid. If the economic and geological conditions are right, the mining company will level large areas of land with a small gradient, layering it with thick plastic (usually HDPE or LLDPE ), sometimes with clay, silt or sand beneath

3525-542: The illusion of prospection for a metal the Soviets definitely weren't after) became the biggest employer in the Saxon Ore Mountains and remote mining towns like Johanngeorgenstadt swelled to ten times their population in a few years. The mining cost immense amounts of money and miners were on the one hand subject to heavier repression and surveillance but on the other hand allowed more generous supply with consumer goods than other East Germans. While production

3600-522: The metric mass measurement in most English -speaking countries. In the United States, the unit was originally referred to using the French words millier or tonneau , but these terms are now obsolete. The British imperial and United States customary units are comparable to the tonne and the spelling of ton in English is the same, though they differ in mass. One tonne is equivalent to: A tonne

3675-574: The mine. In the past mining companies would sometimes go bankrupt, leaving the responsibility of mine reclamation to the public. 21st century additions to US mining law require that companies set aside the money for reclamation before the beginning of the project. The money will be held by the public to insure adherence to environmental standards if the company were to ever go bankrupt. In-situ leaching (ISL), also known as solution mining, or in-situ recovery (ISR) in North America, involves leaving

3750-423: The more efficient acid leach. The Australian government has published a best practice guide for in situ leach mining of uranium, which is being revised to take account of international differences. The uranium concentration in sea water is low, approximately 3.3 parts per billion or 3.3 micrograms per liter of seawater. But the quantity of this resource is gigantic and some scientists believe this resource

3825-415: The native groundwater in the orebody which is fortified with a complexing agent and in most cases an oxidant. It is then pumped through the underground orebody to recover the minerals in it by leaching. Once the pregnant solution is returned to the surface, the uranium is recovered in much the same way as in any other uranium plant (mill). In Australian ISL mines ( Beverley , Four Mile and Honeymoon Mine )

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3900-512: The now-exposed rocks acid mine drainage can be a concern for those newly developing bodies of water. Mining companies are now required by law to establish a fund for future reclamation while mining is ongoing and those funds are usually deposited in such a way as to be unaffected by bankruptcy of the mining company. If the uranium is too far below the surface for open pit mining, an underground mine might be used with tunnels and shafts dug to access and remove uranium ore. Underground uranium mining

3975-734: The only four countries that have reported non-domestic uranium exploration and development expenses are: China, Japan, France, and Russia. The U.S. is investigating whether China is circumventing a ban on Russian uranium imports by exporting its uranium to the U.S. while importing enriched uranium from Russia. This inquiry follows a spike in Chinese uranium exports to the U.S. after the December 2023 ban, which aimed to cut off funding for Russia's war in Ukraine. As with other types of hard rock mining there are several methods of extraction. In 2016,

4050-429: The ore where it is in the ground, and recovering the minerals from it by dissolving them and pumping the pregnant solution to the surface where the minerals can be recovered. Consequently, there is little surface disturbance and no tailings or waste rock generated. However, the orebody needs to be permeable to the liquids used, and located so that they do not contaminate ground water away from the orebody. Uranium ISL uses

4125-514: The oxidant used is hydrogen peroxide and the complexing agent sulfuric acid. Kazakh ISL mines generally do not employ an oxidant but use much higher acid concentrations in the circulating solutions. ISL mines in the USA use an alkali leach due to the presence of significant quantities of acid-consuming minerals such as gypsum and limestone in the host aquifers. Any more than a few percent carbonate minerals means that alkali leach must be used in preference to

4200-482: The particular case of tungsten: Tungsten concentrates are usually traded in metric tonne units (originally designating one tonne of ore containing 1% of WO 3 , today used to measure WO 3 quantities in 10 kg units. One metric tonne unit (mtu) of tungsten (VI) contains 7.93 kilograms of tungsten. In the case of uranium , MTU is sometimes used in the sense of metric ton of uranium (1,000 kg [2,200 lb]). The tonne of trinitrotoluene (TNT)

4275-546: The percentage of the mined uranium produced by each mining method was: in-situ leach (49.7 percent), underground mining (30.8 percent), open pit (12.9 percent), heap leaching (0.4 percent), co-product/by-product (6.1%). The remaining 0.1% was derived as miscellaneous recovery. In open pit mining, overburden is removed by drilling and blasting to expose the ore body, which is then mined by blasting and excavation using loaders and dump trucks. Workers spend much time in enclosed cabins thus limiting exposure to radiation. Water

4350-458: The plastic liner. The extracted ore will typically be run through a crusher and placed in heaps atop the plastic. The leaching agent will then be sprayed on the ore for 30–90 days. As the leaching agent filters through the heap, the uranium will break its bonds with the oxide rock and enter the solution. The solution will then filter along the gradient into collecting pools which will then be pumped to on-site plants for further processing. Only some of

4425-668: The population of laborers to 45,000. At its peak in 1953, the St. Joachimsthal mines had 16,100 inmates, half of whom were Soviet political prisoners. By 1975, 75% of global uranium ore production came from quartz - pebble conglomerates and sandstones located in the Elliot Lake area of Canada , Witwatersrand , and the Colorado Plateau . In 1990, 55% of world production came from underground mines, but this shrank to 33% by 1999. From 2000, new Canadian mines again increased

4500-461: The presence of radioactive isotopes. The Geiger counter was the original radiation detector, recording the total count rate from all energy levels of radiation. Ionization chambers and Geiger counters were first adapted for field use in the 1930s. The first transportable Geiger–Müller counter (weighing 25 kg) was constructed at the University of British Columbia in 1932. H.V. Ellsworth of

4575-656: The production from the Eldorado Mine (Northwest Territories) . According to Richard Rhodes , referring to German uranium research, " Auer , the thorium specialists ... delivered the first ton of pure uranium oxide processed from Joachimsthal ores to the War Office in January 1940. In June 1940 ... Auer ordered sixty tons of refined uranium oxide from the Union Miniére in occupied Belgium." While

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4650-740: The proportion of underground mining, and with Olympic Dam it is now 37%. In situ leach (ISL, or ISR) mining has been steadily increasing its share of the total, mainly due to Kazakhstan. In 2009, top producing mines included the McArthur River uranium mine at 7400 tU, the Ranger Uranium Mine at 4423 tU, the Rössing uranium mine at 3574 tU, the Moiynkum Desert mines at 3250 tU, the Streltsovsk mine at 3003 tU,

4725-559: The same amount. The BIPM symbol for the tonne is t, adopted at the same time as the unit in 1879. Its use is also official for the metric ton in the United States, having been adopted by the United States National Institute of Standards and Technology (NIST). It is a symbol, not an abbreviation, and should not be followed by a period . Use of lower case is significant, and use of other letter combinations can lead to ambiguity. For example, T, MT, mT, are

4800-490: The source of uranium with hydrothermal vein-type deposits and the potential sources still remains a mystery, but are thought to include preexisting rocks that have been broken down by weathering and force that come from areas of long-term sediment build up. The South Chine Block is an example of a region that has been relying on vein-type hydrothermal uranium deposit demand for the past half century. Igneous deposits include nepheline syenite intrusives at Ilimaussaq , Greenland;

4875-404: The sulfuric acid. Heap leach is significantly cheaper than traditional milling processes. The low costs allow for lower grade ore to be economically feasible (given that it is the right type of ore body). US environmental law requires that the surrounding ground water is continually monitored for possible contamination. The mine will also have to have continued monitoring even after the shutdown of

4950-407: The surface area of the ocean floor, both of which maintain the solubility equilibria of seawater concentration at a stable level. Some commentators have argued that this strengthens the case for nuclear power to be considered a renewable energy . Tonne The tonne ( / t ʌ n / or / t ɒ n / ; symbol:  t ) is a unit of mass equal to 1,000  kilograms . It

5025-544: The type of rock in which they are found. This geological classification system is determined by the International Atomic Energy Agency (IAEA). Uranium is also contained in seawater but at present prices on the uranium market , costs would have to be lowered by a factor of 3–6 to make its recovery economical. Uranium deposits in sedimentary rocks include those in sandstone (in Canada and

5100-415: The uranium (commonly about 70%) is actually extracted. The uranium concentrations within the solution are very important for the efficient separation of pure uranium from the acid. As different heaps will yield different concentrations, the solution is pumped to a mixing plant that is carefully monitored. The properly balanced solution is then pumped into a processing plant where the uranium is separated from

5175-505: The uranium market as U 3 O 8 . While some nuclear power plants – most notably heavy water reactors like the CANDU – can operate with natural uranium (usually in the form of uranium dioxide ), the vast majority of commercial nuclear power plants and many research reactors require uranium enrichment , which raises the content of U from the natural 0.72% to 3–5% (for use in light water reactors ) or even higher , depending on

5250-406: The world's best adsorbents," said Chris Janke, one of the inventors and a member of ORNL's Materials Science and Technology Division. HiCap also effectively removes toxic metals from water, according to results verified by researchers at Pacific Northwest National Laboratory . In 2012 it was estimated that this fuel source could be extracted at 10 times the current price of uranium. In 2014, with

5325-421: The world's mined uranium is used to power nuclear power plants . Historically uranium was also used in applications such as uranium glass or ferrouranium but those applications have declined due to the radioactivity and toxicity of uranium and are nowadays mostly supplied with a plentiful cheap supply of depleted uranium which is also used in uranium ammunition . In addition to being cheaper, depleted uranium

5400-399: Was >1 kg of yellowcake after 240 days of submersion in the ocean. The experiment by Seko et al. was repeated by Tamada et al. in 2006. They found that the cost varied from ¥15,000 to ¥88,000 depending on assumptions and "The lowest cost attainable now is ¥25,000 with 4g-U/kg-adsorbent used in the sea area of Okinawa, with 18 repetitionuses [ sic ]." With

5475-448: Was conducted by Eldorado Mining and Refining Limited . (a Canadian Crown Corporation since sold to become Cameco Corporation ). The first patent for a portable gamma-ray spectrometer was filed by Professors Pringle, Roulston & Brownell of the University of Manitoba in 1949, the same year as they tested the first portable scintillation counter on the ground and in the air in northern Saskatchewan . Airborne gamma-ray spectrometry

5550-473: Was never able to compete with global uranium market prices, the dual use nature of the mined material as well as the possibility to pay miners in soft currency but sell uranium for hard currency or substitute imports which would have had to be paid for in hard currency tipped the scales in favor of continuing mining operations throughout the Cold War. After German reunification , mining was wound down and

5625-764: Was produced from 1850 and 1898, with 10,000 tU produced before closure in 1968. In 1871, uranium ore mining began in Central City, Colorado , where 50 t were mined before 1895. In 1873, the uranium mining began in the South Terras mine, St Stephen-in-Brannel , Cornwall, producing most of the 300 tU from that area in the 19th century. In 1898, carnotite was first mined in the Uravan Mineral Belt , yielding 10 tU annually. In 1898, Pierre Curie and Marie Skłodowska-Curie took delivery of 1 t of pitchblende from St. Joachimsthal, from which Marie identified

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