Uranium mining
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224158154
2008-07-07T16:12:09Z
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[[Image:Ranger Uranium Mine in Kakadu National Park.jpg|thumb|right|The Ranger Uranium Mine in Australia.]]
'''Uranium mining''' is the process of extraction of [[uranium]] [[ore]] from the ground. As uranium ore is mostly present at relatively low concentrations, most uranium mining is very volume-intensive, and thus tends to be undertaken as [[open-pit mining]]. It is also undertaken in only a small number of countries of the world, as the resource is relatively rarely found.
The worldwide production of uranium in 2003 amounted to 41,429 [[tonne]]s, of which 25% was mined in [[Canada]]. Other important uranium mining countries are [[Australia]], [[Russia]], [[Niger]], [[Namibia]], [[Kazakhstan]], [[Uzbekistan]], [[South Africa]], and the [[USA]].
A prominent use of uranium from mining is as fuel for [[nuclear power plant]]s. [[As of 2008]], known uranium ore resources which can be mined at about current costs are estimated to be sufficient to produce fuel for about a century, based on current consumption rates.<ref>{{cite web
| url= http://www.nea.fr/html/general/press/2008/2008-02.html
| title= "Uranium resources sufficient to meet projected nuclear energy requirements long into the future"
| date= 3 June 2008 | publisher= [[Nuclear Energy Agency]] (NEA)
| quote= ''Uranium 2007: Resources, Production and Demand'', also known as the Red Book, estimates the identified amount of conventional uranium resources which can be mined for less than USD 130/kg to be about 5.5 million tonnes, up from the 4.7 million tonnes reported in 2005. Undiscovered resources, i.e. uranium deposits that can be expected to be found based on the geological characteristics of already discovered resources, have also risen to 10.5 million tonnes. This is an increase of 0.5 million tonnes compared to the previous edition of the report. The increases are due to both new discoveries and re-evaluations of known resources, encouraged by higher prices.
| accessdate= 2008-06-16 }}</ref>
== History ==
Uranium minerals were noticed by miners for a long time prior to the discovery of uranium in 1789. The uranium mineral [[pitchblende]] was reported from the Saxonian Ore Mountains (Erzegebirge) as early as 1565. Other early reports of pitchblende date from 1727 ([[Joachimsthal]]) and 1763 ([[Schwarzwald]]).<ref> Franz J. Dahlkamp (1993) ''Uranium ore deposits'' Springer-Verlag, Berlin, 460 p. ISBN 3-540-53264-1.</ref>
In the early 1800s, uranium ore was recovered as a by-product of mining in [[Saxony]], [[Bohemia]], and [[Cornwall]]. The first deliberate mining of [[Radioactive|radioactive ores]] took place in [[Jáchymov]] (also known by its German name, [[Joachimsthal]]), a silver-mining city in what is now the [[Czech Republic]]. [[Marie Curie]] used [[pitchblende]] ore from Jáchymov to isolate the element [[radium]], a [[decay product]] of uranium; her death was from [[aplastic anemia]], almost certainly due to exposure to [[radioactivity]]. Until [[World War II]] uranium mining was done primarily for the radium content. Sources for [[radium]] (contained in uranium ore) were sought for use as [[luminous]] paint for watch dials and other instruments, as well as for health-related applications (some of which in retrospect were incredibly unhealthy). The byproduct uranium was used mostly as a yellow pigment.
In the United States, the first radium/uranium ore was discovered in 1871 in [[gold]] mines near [[Central City, Colorado]]. This district produced about 50 tons of high grade ore between 1871 and 1895. However, most American uranium ore before [[World War II]] came from [[vanadium]] deposits on the [[Colorado Plateau]] of [[Utah]] and [[Colorado]].
In [[Cornwall]], the South Terras Mine near [[St. Stephen]] opened for uranium production in 1873, and produced about 175 tons of ore before 1900. Other early uranium mining occurred in Autunois in France's [[Massif Central]], Oberpfalz in [[Bavaria]], and Billingen in Sweden.
The Shinkolobwe deposit in [[Katanga]], [[Belgian Congo]] now [[Shaba Province]], [[Zaire]] was discovered in 1913, and exploited by the [[Union Minière du Haut Katanga]]. Other important early deposits include [[Port Radium]], near [[Great Bear Lake]], [[Canada]] discovered in 1931, along with [[Beira Province]], [[Portugal]]; [[Tyuya Muyun]], [[Uzbekistan]], and [[Radium Hill]], [[Australia]].
Because of the need for the uranium for bomb research during [[World War II]], the [[Manhattan Project]] used a variety of sources for the element. The Manhattan Project initially purchased uranium ore from the [[Belgian Congo]], through the [[Union Minière du Haut Katanga]]. Later the project contracted with vanadium mining companies in the American Southwest. Purchases were also made from the [[Eldorado Mining and Refining Limited]] company in Canada. This company had large stocks of uranium as waste from its radium refining activities.
American uranium ores mined in Colorado were mixed ores of vanadium and uranium, but because of wartime secrecy the Manhattan Project would only publicly admit to purchasing the vanadium, and did not pay the uranium miners for the uranium content. (In a much later lawsuit, many miners were able to reclaim lost profits from the U.S. government.) American ores had much lower uranium concentrations than the ore from the Belgian Congo, but they were pursued vigorously to ensure nuclear self-sufficiency.
Similar efforts were undertaken in the [[Soviet Union]], which did not have native stocks of uranium when it started developing its own atomic weapons program.
Intensive exploration for uranium started after the end of [[World War II]] as a result of the military and civilian demand for uranium. There were three separate periods of uranium exploration or "booms." These were from 1956 to 1960, 1967 to 1971, and from 1976 to 1982.
In the 20th century the United States was the world's largest uranium producer. Grants Uranium District in northwestern New Mexico was the largest United States uranium producer. The Gas Hills Uranium District, was the second largest uranium producer. The famous Lucky Mc Mine is located in the Gas Hills near Riverton, Wyoming. Canada has since surpassed the United States as the cumulative largest producer in the world.
== By territory ==
{{seealso | List of uranium mines}}
=== Oceania ===
==== Australia ====
{{See also|Uranium mining controversy in Kakadu National Park}}
[[Australia]] has the world's largest uranium reserves - 24 percent of the planet's known reserves. The majority of these reserves are located in South Australia with other important deposits in Queensland, Western Australia and the Northern Territory. Almost all the uranium is exported under strict [[International Atomic Energy Agency]] safeguards to satisfy the Australian people and government that none of the uranium is used in [[nuclear weapons]]. Australian uranium is used strictly for electricity production; however, some argue this still frees other uranium to be used in weapons.
The [[Olympic Dam]] operation run by [[BHP Billiton]] in [[South Australia]] is combined with mining of [[copper]], [[gold]], and [[silver]], and has reserves of global significance. There are currently three operating uranium mines in Australia, and several more have been proposed. The expansion of uranium mining in Australia is supported by the Federal Australian Labor Party (ALP) Government headed by Prime Minister Kevin Rudd. The ALP abandoned its long-standing and controversial "no new uranium mines" policy in April 2007. One of the more controversial proposals was [[Jabiluka]], to be built inside the [[World Heritage]] listed [[Kakadu National Park]]. The existing [[Ranger Uranium Mine]] is surrounded by the National Park as the mine area was not included in the original listing of the Park.
Uranium mining and export and related nuclear issues have often been the subject of public debate, and the [[anti-nuclear movement in Australia]] has a long history.<ref>[http://www.greenleft.org.au/1998/330/20531 Australia's anti-nuclear movement: a short history]</ref>
=== Americas ===
==== Arizona ====
On Wednesday 25th June 2008 the House Natural Resources Committee voted overwhelmingly to enact emergency protections from uranium mining for 1 million acres of public lands around [[Grand Canyon]] National Park. This will mean the Secretary of the Interior has an obligation to protect public lands near the Grand Canyon from uranium extraction for three years. The [http://www.biologicaldiversity.org/The Center for Biological Diversity], [[Sierra Club]], and the Grand [http://www.grandcanyontrust.org/Grand Canyon Trust] recently won a court order against the [[Kaibab National Forest]] stopping uranium drilling near the national park until a thorough environmental analysis is conducted.[http://www.azcentral.com/arizonarepublic/news/articles/0626grandcanyon.html]
The Grand Canyon Watersheds Protection Act has been proposed. This is a bill that would permanently ban uranium mining in the area.
The impacts of uranium development have raised concerns of scientists and government officials alike. Due to increasing demand, uranium projects have been on the increase
posing a threat to water, public health, and fragile desert ecosystems.
==== Canada ====
[[Canada]] is the largest exporter of uranium ore,<ref>
{{cite web |url=http://www.world-nuclear.org/info/inf49.html
|title=Canada's Uranium Production & Nuclear Power
|accessdate=2008-05-26
|publisher=World Nuclear Association
|year=2008
|month=May
}}</ref> with the largest mines located in [[Athabasca Basin]] in northern [[Saskatchewan]].
Canada's first uranium discovery was in the '''Alona Bay''' area, south of [[Lake Superior Provincial Park]] in Ontario, by Dr. John Le Conte in 1847.<ref>Nuffield, E. W., 1955, Geology of the Montreal River Area; Ontario Department of Mines, Volume LXIV, Part 3, Sixty-Fourth Annual Report.</ref> But the Canadian uranium industry really began with the 1932 discovery of [[pitchblende]] at [[Port Radium, Northwest Territories]]. The deposit was mined from 1933 to 1940, for [[radium]], [[silver]], [[copper]], and [[cobalt]]. The mine shut down in 1940, but was reopened in 1942 by [[Eldorado Mining and Refining Limited]] to supply uranium to the [[Manhattan Project]]. The Canadian government expropriated the Port Radium mine and banned private claimstaking and mining of radioactive minerals.<ref>Carlie F. Banks (1976) Uranium and the Uranium Industry in Canada, Richardson, Tex.: Suntech Inc., p. 36–37.</ref>
In 1947 the government lifted the ban on private uranium mining, and the industry boomed through the 1950s, spurred by high prices due to the nuclear weapons programs. Production peaked in 1959, when 23 mines in five different districts made uranium Canada’s number-one export. That same year, however, [[Great Britain]] and the [[United States]] announced their intention to halt uranium purchases in 1963. By 1963, seven mines were left operating, a number that shrunk to only three in 1972.
A price rise caused uranium to boom again in 1975.
===== Ontario =====
In 1948, prospector Robert Campbell discovered [[pitchblende]] at '''Theano Point''', in the area of Alona Bay, Ontario, and staked 30 claims. By November 1948 a rush had begun, and in the next three years, 5,000 claims would be staked in the area. A shaft and headframe were constructed, but abandoned before operations could begin; the mine proved unprofitable after uranium discoveries at [[Elliot Lake]], Ontario.<ref>Chisholm, B., and Gutsche, A., ''Superior, Under the Shadow of the Gods'', Lynx Images, 1998, p. 45.</ref>
The uranium-bearing [[pegmatite]] of [[Bancroft, Ontario]] began mining in 1952.
Uranium was discovered at [[Blind River, Ontario|Blind River]]-[[Elliot Lake, Ontario|Elliot Lake]] area in 1949, and production began in 1955. The deposits are in [[Precambrian]] [[quartz]]-pebble [[Conglomerate (geology)|conglomerate]]s, similar to uranium deposits in [[Brazil]] and [[South Africa]].
===== Saskatchewan =====
Pitchblende veins were discovered near [[Beaverlodge, Saskatchewan]] in 1935, and uranium mining started in 1953.<ref>J. B. Mawdsley (1958) ''The radioactive pegmatities of Saskatchewan'', in Proceedings of the Second United Nations International Conference on the Peaceful Uses of Atomic Energy, p. 484–490.</ref>
Today the [[Athabasca Basin]] in northern [[Saskatchewan]] hosts the largest high-grade uranium mines and deposits. [[Cameco Corporation|Cameco]], the world’s largest low-cost uranium producer, which accounts for 18% of the world’s uranium production, operates three mines and one dedicated mill in the region. Among the major mines are Cameco's flagship [[McArthur River mine]], the developing [[Cigar Lake mine]], the [[Rabbit Lake mine]] and mill complex, and the world's largest uranium mill at [[Key Lake]]. French-owned uranium syndicate [[Areva]] also operates the McClean Lake mill. Most of these mines are joint ventures between Cameco, Areva, and various other joint venture shareholders. Future mines currently in early development stages include Areva's Midwest Project (near McClean Lake), and Cameco's Millennium Project (near Key Lake). [[As of 2007]], with uranium spot market prices well over the $100 USD/lb mark, Saskatchewan has become a hotbed of uranium exploration, with many junior exploration companies rushing to explore the highly valuable Athabasca basin.
==== United States ====
{{main|Uranium mining in the United States}}
Most uranium ore in the [[United States]] comes from deposits in [[sandstone]], which tend to be of lower grade than those of [[Australia]] and [[Canada]]. Because of the lower grade, many uranium deposits in the [[United States]] became uneconomic when the price of uranium declined sharply in the 1980s.
Regular production of uranium-bearing ore in the United States began in 1898 with the mining of [[carnotite]]-bearing sandstones of the [[Colorado Plateau]] in [[Colorado]] and [[Utah]], for their [[vanadium]] content. The discovery of [[radium]] by [[Marie Curie]], also in 1898, soon made the ore also valuable for radium. Uranium was a by-product. By 1913, the [[Colorado Plateau]] uranium-vanadium province was supplying about half the world supply of radium. Production declined sharply after 1923, when low-cost competition from radium from the [[Belgian Congo]] and [[vanadium]] from [[Peru]] made the [[Colorado Plateau]] ores uneconomic.<ref>Robert J. Wright and Donald L. Everhart (1960) ''Uranium'', in Mineral Resources of Colorado First Sequel, Denver: Colorado Mineral Resources Board, p. 329–365.</ref>
Mining revived in the 1930s with higher prices for vanadium. American uranium ores were in very high demand by the [[Manhattan Project]] during [[World War II]], although the mining companies did not know that the by-product uranium was suddenly valuable. The late 1940s and early 1950s saw a boom in uranium mining in the western US, spurred by the fortunes made by prospectors such as [[Charlie Steen]].
Uranium mining declined with the last [[open pit mine]] shutting down in 1992 (Shirley Basin, Wyoming. United States production occurred in the following states (in descending order): New Mexico, Wyoming, Colorado, Utah, Texas, Arizona, Florida, Washington, and South Dakota. The collapse of uranium prices caused all conventional mining to cease by 1992. [[In-situ leach]] mining has continued primarily in Wyoming and adjacent Nebraska as well has recently restarted in Texas. Rising uranium prices since 2003 have increased interest in uranium mining in the United States.
=== Europe ===
==== Czech Republic ====
Uranium mining took place at [[Jáchymov]] from 1948 to 1964 as well as other places, like [[Horní Slavkov]] and [[Příbram]], later becoming infamously known as parts of the "Czech Gulag".<ref> See article in Czech: ''[[:cs:Koncentrační tábory při československých uranových dolech]]''. </ref>
Today, the [[Rožná]] underground facility is Europe’s only operating uranium mine, continuously operating since 1957.
Since 2007, the Australian company [[Uran Ltd.]] is interested to participate in the operations at Rožná, as well as seeking permits with the Czech Ministry of Trade and Resources to open mines in Czechia at other known locations, like [[Brzkov]], [[Jamné]], [[Polná]] and [[Věžnice]], through its Czech partner Timex Zdice and since 2008 through its subsidiary Urania Mining.<ref>
{{citation |url=http://www.praguepost.com/articles/2008/05/07/uran-stumbles-in-wooing-towns.php |title=Uran stumbles in wooing towns |publisher= Victor Velek, ''[[The Prague Post]]'' |date=7 May 2008}} </ref><ref>
{{citation |url=http://www.bruessel.austria.be/cz/news/local/uran-limited-bemueht-sich-um-uranabbau-in-der-vysocin.en.jsp |title=Uran Limited wants to open a new uranium mine in Havlickuv Brod district |publisher=Advantage Austria, Commercial Section of the Austrian Embassy in Prague |date=17 April 2008}}</ref><ref>
{{citation |url=http://www.uranlimited.com.au/documents/URA_CzechNegotiations_29-1-07.pdf |format= PDF |title=Negotitations with government of Czech Reublic regarding Rozna uranium mine |publisher=Uran Ltd. |date=29 January 2007}}</ref>
====England====
The South Terras Mine in Cornwall was mined for uranium from 1873 to 1903.<ref>[http://www.cornwall-calling.co.uk/mines/st-austell/south-terras.htm Cornwall Calling: ''South Terras Mine, Cornwall'']</ref>
==== Germany ====
Uranium was mined from 1947 to 1990 from mines in Saxony. One of the former uranium producers is the Königstein mine, presently being flooded by Wismut GmbH, which plans to recover an estimated 2 million pounds (770 tonnes) [[triuranium octoxide|{{chem|U|3|O|8}}]] from the mine water.<ref>{{cite web
| url= http://www.ga.com/nuclearfuels.php
| title= Nuclear Fuels Corporation
| publisher= General Atomics
| accessdate= 2008-05-10 }} </ref>
==== Hungary ====
In [[Hungary]] uranium mining began in the 1950s around [[Pécs]] to supply the country's first atomic plant in [[Paks]]. After the fall of communism, uranium mining was gradually given up because of the high production costs. That caused serious economic problems and a rise of unemployment in Pécs.
==== Russia ====
The former Uranium Institute<ref>{{cite web
| url= http://64.233.183.104/search?q=cache:b6SdYpk2usoJ:www.world-nuclear.org/sym/1997/symrep97.htm+uranium+mining+Lake+Baikal&hl=en&ct=clnk&cd=4&gl=uk
| title= An overview of the Uranium Institute's 22nd Annual Symposium
|date= 3–5 September 1997 |work= |publisher= Uranium Institute
| accessdate= 2008-05-10 }} </ref> now the World Nuclear Association<ref>{{cite web
| url= http://www.world-nuclear.org/
| title= World Nuclear Association
| accessdate= 2008-05-10 }} </ref> states that Russia has known uranium deposits of 500,000 tonnes and plans to mine 11,000 to 12,000 tonnes per year from deposits in the South Urals, Western Siberia, and Siberia east of Lake Baikal, by 2010.
==== Scotland ====
Substantial uranium deposits were found on [[Orkney]] in the 1970s,<ref>{{cite web
| url= http://www.scottish.parliament.uk/business/officialReports/meetingsparliament/or-05/sor1110-02.htm
| title= Official Report 10 November 2005 | publisher= [[Scottish Parliament]]
| accessdate= 2008-05-10 }} </ref> When [[Margaret Thatcher]] proposed a uranium mine on Orkney a campaign followed which successfully argued that uranium mining would mean irreversible environmental, social and psychological damage.<ref>{{cite web
| url= http://www.chamberoperamemphis.org/the_composer%20of%20The%20Medium.htm
| title= Peter Maxwell Davies
|date= |year= |month= |format= |work= |publisher= The Chamber Opera of Memphis
| accessdate= 2008-05-10 }} </ref>
==== Sweden ====
In [[Sweden]] developmental uranium mining of oil shale deposits took place at Ranstadsverket between 1965 and 1969. The goal was to make Sweden self-supplying with uranium. The high operating costs of the pilot plant (heap leaching) due to the low concentration of uranium in the shale and the, at that time, availability of comparatively cheap uranium on the world market, caused the mine to be closed, although a much cheaper and more efficient leaching process, using sulfur-consuming bacteria, had by then been developed. Since 2005 there have been investigations on opening new uranium mines in Sweden.
=== Africa ===
==== Namibia ====
[[Namibia]] produces uranium at [[Rossing]] deposit, where an [[igneous]] deposit is mined from one of the world’s largest [[Open pit mining|open pit mines]]. The mine is owned by a subsidiary of the [[Rio Tinto Group]].<ref>George J. Coakley (2004) ''Namibia'', in Minerals Yearbook, Area Reports: International 2002, Africa and the Middle East, U.S. Geological Survey, p. 24.2.</ref> The Langer Heinrich calcrete uranium deposit was discovered in 1973 and the open pit mine was officially opened in 2007.<ref>[http://www.infomine.com/minesite/minesite.asp?site=langerheinrich Langer Heinrich mine]</ref>
==== Niger ====
Niger is Africa’s leading uranium-producing nation. Uranium is produced from mines at [[Arlit]] owned by [[Areva NC]].<ref>Thomas R. Yager (2004) ''Burkina Faso, Mauritania, and Niger'', in Minerals Yearbook, Area Reports: International 2002, Africa and the Middle East, U.S. Geological Survey, p. 6.2.</ref>
Niger's uranium came to world attention before the US invasion of Iraq, when it was asserted that Iraq had attempted to buy uranium from Niger (see ''[[Niger uranium forgeries]]'').
==== South Africa ====
South Africa produces uranium from deposits in [[Precambrian]] [[quartz]]-pebble [[Conglomerate (geology)|conglomerate]]s of the [[Witwatersrand Basin]], at [[Brakpan, Gauteng|Brakpan]] and [[Krugersdorp, Gauteng]].
=== India ===
In [[Nalgonda District]], the [[Rajiv Gandhi Tiger Reserve]] (the only [[tiger]] project in [[Andhra Pradesh]]) has been forced to surrender over 1,000 sq. kilometres to uranium mining following a directive from the [[Central Ministry of Environment and Forests]].<ref>{{cite web
| url= http://www.wildlifewatch.in/news/1004
| title= Tiger reserve in Andhra made to shrink legally
|date=January 7, 2008 |work= |publisher= Wildlifewatch.in
| accessdate= 2008-05-22 }}</ref>
== Exploration ==
Uranium prospecting is similar to other forms of mineral exploration with the exception of some specialized instruments for detecting 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 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 counter]]s.
The use of [[airborne detector]]s 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 [[Radiometer|radiation detector]]s (ionization chambers and Geiger counters) 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 is now the accepted leading technique for uranium prospecting with worldwide applications for geological mapping, mineral exploration & environmental monitoring.
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 the amounts of ore that are estimated to be recoverable at stated costs.
== Types of uranium deposits ==
Many different types of uranium deposits have been discovered and mined.
=== Uranium deposits in sedimentary rock ===
Uranium deposits in sedimentary rocks include those in sandstone (in Canada and the [[Western United States|western US]]),<ref name="TENORM Uranium V1, Distribution">{{Citation
|title=Technologically Enhanced Naturally Occurring Radioactive Materials From Uranium Mining
|volume=1: "Mining and Reclamation Background"
|first1=Sanjib |last1=Chaki
|first2=Elliot |last2=Foutes
|first3=Shankar |last3=Ghose
|first4=Brian |last4=Littleton
|first5=John |last5=Mackinney
|first6=Daniel |last6=Schultheisz
|first7=Mark |last7=Schuknecht
|first8=Loren |last8=Setlow
|first9=Behram |last9=Shroff
|first10=Thomas |last10=Peake
|date=January 2006
|publisher=[[US Environmental Protection Agency]] Office of Radiation and Indoor Air
Radiation Protection Division
|location=Washington, DC
|url=http://www.epa.gov/radiation/docs/tenorm/402-r-05-007.pdf
|pages=1--8 to 1--9
}}</ref>
[[Precambrian]] [[unconformity|unconformities]] (in Canada),<ref name="TENORM Uranium V1, Distribution"/>
[[phosphate]],<ref name="TENORM Uranium V1, Distribution"/>
[[Precambrian]] [[quartz]]-pebble [[Conglomerate (geology)|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 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 (geology)|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 the [[Blind River, Ontario|Blind River]]-[[Elliot Lake]] district of Ontario, Canada, and from the gold-bearing [[Witwatersrand]] conglomerates of [[South Africa]].
=== Igneous or hydrothermal uranium deposits ===
Hydrothermal uranium deposits encompass the vein-type uranium ores. Igneous deposits include [[nepheline]] [[syenite]] intrusives at Ilimaussaq, [[Greenland]]; the disseminated uranium deposit at [[Rossing]], Namibia; and uranium-bearing [[pegmatite]]s. Disseminated deposits are also found in the states of Washington and Alaska in the US.<ref name="TENORM Uranium V1, Distribution"/>
== Mining techniques ==
As with other types of [[Underground mining (hard rock)|hard rock mining]] there are several methods of extraction. The main methods of mining are ''[[box cut]]'' mining, ''[[open pit]]'' mining and ''in situ leaching'' (ISL).
=== Open pit ===
In [[open pit mining]], [[overburden]] is removed by drilling and blasting to expose the ore body which is mined by blasting and excavation via loaders and dump trucks. Workers spend much time in enclosed cabins thus limiting exposure. Water is extensively used to suppress airborne dust levels.
=== Underground uranium mining ===
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]]. There is less waste material removed from underground mines than open pit mines, however this type of mining exposes underground workers to the highest levels of radon gas.
Underground uranium mining is in principle no different to any other [[Underground mining (hard rock)|hard rock mining]] and other ores are often mined in association (eg [[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 the crosscut. To win the ore, the next step is to drive tunnels, known as raises when driven upwards and winzes when driven downwards through the deposit from level to level. These raises are subsequently used to develop the stopes where the ore is mined in the veins.
The stope, which is the workshop of the mine, is the excavation from which the ore is being extracted. Two methods of stope mining are commonly used. In the “cut and fill” method and open stopping method, the space remaining following removal of ore after blasting is filled with waste rock and cement. In the “shrinkage” method just sufficient broken ore is removed via the chutes below to allow the miners to work from the top of the pile to drill and blast for the next layer to be broken off; eventually leaving a large hole. Another method, known as room and pillar, 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 sufficient for roof support.
=== Heap leaching ===
Waste rock is produced during open pit mining when [[overburden]] is removed, and during underground mining when driving tunnels through non-ore zones.
Piles of these [[tailings]] often contain elevated concentrations of [[radioisotope]]s compared to normal rock. Other waste piles consist of ore with too low a grade for processing. The transition between waste rock and ore depends on technical and economic feasibility criteria. All these piles threaten people and the environment after shut down of the mine due to their release of [[radon]] gas and seepage water containing [[radioactive]] and toxic materials.
In some cases uranium has been removed from this low-grade ore by heap leaching. This may be done if the uranium contents is too low for the ore to be economically processed in a uranium mill. The leaching liquid (often [[sulfuric acid]]) is introduced on the top of the pile and percolates down until it reaches a liner below the pile, where it is caught and pumped to a processing plant. Due to the potential for extreme damage to the surrounding environment , this practice is no longer in use.
=== ''In-situ'' leaching ===
[[In-situ leaching]] (ISL), sometimes referred to as ''in-situ recovery'' (ISR) or ''solution mining'', is performed by pumping liquids (weak [[acid]] or weak [[alkaline]] depending on the [[calcium]] concentration in the ore) down through injection wells placed on one side of the deposit of uranium, through the deposit, and up through recovery wells on the opposing side of the deposit - recovering ore by [[leaching]]. ISL is also used on other types of metal extraction such as [[copper]]. ISL is often cost-effective because it avoids excavation costs, and may be implemented more quickly than conventional mining. However, it is not suitable to all uranium deposits, as the host rock must be permeable to the liquids (as is often the case in [[sandstone]]).
Environmental impact studies are performed when evaluating ISL, because [[ground water]] can be affected. [[In-situ leaching]] is the only type of uranium mining currently being done in the United States (2006).
=== Recovery from seawater ===
The uranium concentration of sea water is low, approximately 3.3 mg per [[cubic meter]] of seawater (3.3 ppb). But the quantity of this resource is gigantic and some scientists believe this resource 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.<ref>{{cite web
| url= http://www.wise-uranium.org/upusa.html#SEAWATER
| title= Presidential Committee recommends research on uranium recovery from seawater
|author= |last= |first= |authorlink= |coauthors=
|date= August 2, 1999 |format= link to [[PDF]] |work=
| publisher= The President's Committee Of Advisors On Science And Technology
| quote= ... this resource ... could support for 6,500 years 3,000 GW of nuclear capacity ... Research on a process being developed in Japan suggests that it might be feasible to recover uranium from seawater at a cost of $120 per lb of U<sub>3</sub>O<sub>8</sub>.<sup><small>[40]</small></sup> Although this is more than 10 times the current uranium price, it would contribute just 0.5¢ per kWh to the cost of electricity for a next-generation reactor operated on a once-through fuel cycle—...
| accessdate= 2008-05-10 }} </ref> Some anti-nuclear 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 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 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 absorbent. The total amount of uranium recovered from three collection boxes containing 350 kg of fabric was >1 kg of yellowcake after 240 days of submersion in the ocean.<ref name="SekoEtAl2003">{{cite journal
|url=http://www.ans.org/pubs/journals/nt/va-144-2-274-278
|title=Aquaculture of Uranium in Seawater by a Fabric-Adsorbent Submerged System
|journal=Nuclear Technology
|publisher=American Nuclear Society
|author=Noriaki Seko, Akio Katakai, Shin Hasegawa, Masao Tamada, Noboru Kasai, Hayato Takeda, Takanobu Sugo, Kyoichi Saito
|date=November 2003
|volume=144
|number=2
|accessdate=2008-04-30
}}</ref> According to the OECD, uranium may be extracted from seawater using this method for about $300/kg-U.<ref name=OECDredbook2003p22>{{cite web
|url=http://www.neutron.kth.se/courses/reactor_physics/NEA-redbook2003.pdf
|title=Uranium Resources 2003: Resources, Production and Demand
|publisher=OECD World Nuclear Agency and International Atomic Energy Agency
|author=
|date=2008-03
|page=p. 22
|language=English
|accessdate=2008-04-23
}}</ref> 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 (Yen) 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 the May, 2008 exchange rate, this was about $240/kg-U.<ref>{{cite journal
|url=http://jolisfukyu.tokai-sc.jaea.go.jp/fukyu/mirai-en/2006/4_5.html
|author=Tamada M. ''et al''.
|title=Cost Estimation of Uranium Recovery from Seawater with System of Braid type Adsorbent
|publisher=Nippon Genshiryoku Gakkai Wabun Ronbunshi
|volume=5
|number=No. 4
|date=2006
|pages=p. 358–363
|language=Japanese, translated into English
|accessdate=2008-05-10
}}</ref>
== Rise, stagnation, renaissance and opposition to uranium mining ==
In the beginning of the [[Cold War]], to ensure adequate supplies of uranium for national defense, the United States Congress passed the [[Atomic Energy Act of 1946|U.S. Atomic Energy Act of 1946]], creating the [[United States Atomic Energy Commission|Atomic Energy Commission]] (AEC) which had the power to withdraw prospective uranium mining land from public purchase, and also to manipulate the price of uranium to meet national needs. By setting a high price for uranium ore, the AEC created a uranium "boom" in the early 1950s, which attracted many prospectors to the [[Four Corners (United States)|four corners region]] of the country. [[Moab, Utah]] became known as the Uranium-capital of the world, when geologist [[Charles Steen]] discovered such an ore in 1952, even though American ore sources were considerably less potent than those in the Belgian Congo or [[South Africa]].
At the height of the [[nuclear energy]] [[wiktionary:Euphoria|euphoria]] in the 1950s methods for extracting diluted uranium and [[thorium]], found in abundance in [[granite]] or [[seawater]], were pursued.<ref> {{cite web
| url= http://www.ornl.gov/info/ornlreview/rev25-34/chapter4.shtm
| title= Chapter 4: Olympian Feats
|author= |last= |first= |authorlink= |coauthors=
|date= |year= |month= | work= Oak Ridge National Laboratory Review
| publisher= [[Oak Ridge National Laboratory]], [[United States Department of Energy|U.S. Dept. of Energy]]
| accessdate= 2008-05-10 }} </ref> Scientists promised that, used in a [[breeder reactor]], these materials would potentially provide limitless source of energy.
American military requirements declined in the 1960s, and the government completed its uranium procurement program by the end of 1970. Simultaneously, a new market emerged: commercial nuclear power plants. However, in the U.S. this market virtually collapsed by the end of the 1970s as a result of industrial strains caused by the [[energy crisis]], popular opposition, and finally the [[Three Mile Island accident|Three Mile Island nuclear accident]] in 1979, all of which led to a ''de facto'' moratorium on the development of new nuclear reactor power stations.
In [[Europe]] a mixed situation exists. Considerable nuclear power capacities have been developed, notably in [[Belgium]], [[France]], [[Germany]], [[Spain]], [[Sweden]], [[Switzerland]] and the [[United Kingdom|UK]]. In many countries development of [[nuclear power]] has been stopped and phased out by legal actions. In [[Italy]] the use of nuclear power was barred by a [[referendum]] in 1987, however this is now under revision.<ref>{{cite web
| url= http://www.nytimes.com/2008/05/23/world/europe/23nuke.html?partner=rssnyt&emc=rss
| title= Italy Embraces Nuclear Power
| last= Rosenthal | first= Elisabeth | date= May 23, 2008 | publisher= ''[[The New York Times]]''
| accessdate= 2008-05-22 }}</ref> [[Ireland]] also has no plans to change its non-nuclear stance and pursue nuclear power in the future.{{Fact|date=February 2007}}
Since 1981 uranium prices and quantities in the US are reported by the [[United States Department of Energy|Department of Energy]].<ref>{{cite web
| url= http://www.eia.doe.gov/cneaf/nuclear/umar/summarytable1.html
| title= Table S1: Uranium Purchased by Owners and Operators of U.S. Civilian Nuclear Power Reactors
| date= May 16, 2007 | work= Uranium Marketing Annual Report
| publisher= [[Energy Information Administration]], U.S. DoE
| accessdate= 2008-05-10 }} </ref><ref>{{cite web
| url= http://www.eia.doe.gov/emeu/aer/pdf/pages/sec9.pdf
| title= Section 9: Nuclear Energy
|date= |year= |month= |format= [[PDF]] |work= | publisher= Energy Information Administration, U.S. DoE
| accessdate= 2008-05-10 }} </ref>
The import price dropped from 32.90 US$/lb-U<sub>3</sub>O<sub>8</sub> in 1981 down to 12.55 in 1990 and to below 10 US$/lb-U<sub>3</sub>O<sub>8</sub> in the year 2000. Prices paid for uranium during the 1970s were higher, 43 US$/lb-U<sub>3</sub>O<sub>8</sub> is reported as the selling price for [[Australia]]n uranium in 1978 by the [http://www.ccsa.asn.au/nic/Uranium/UMarket.htm Nuclear Information Centre].
Uranium prices reached an all-time low in 2001, costing US$7/lb, but has since rebounded strongly and in the last few months extremely so. In April 2007 the price of Uranium on the spot market rose to US$113.00/lb.<ref>{{cite web
| url= http://www.miningmx.com/energy/801287.htm
| title= Uranium prices will correct soon
| last= Seccombe | first= Allan
|date= 24 Apr 2007 |work= |publisher= Miningmx.com
| accessdate= 2008-05-10 }} </ref> This is very close to the all time high (adjusted for inflation) in 1977.<ref>{{cite web
| url= http://www.uxc.com/review/uxc_g_hist-price.html
| title= Constant 2007 US$ vs. Current US$ Spot U<sub>3</sub>O<sub>8</sub> Prices
|date= |year= |month= |format= |work= | publisher= Ux Consulting Company, LLC
| accessdate= 2008-05-10 }} </ref> The higher price has spurred expansion of current mines, construction of new mines and reopening of old mines as well as new prospecting.
== Health risks of uranium mining ==
Because uranium ore emits [[radon]] gas, uranium mining can be more dangerous than other underground mining, unless adequate ventilation systems are installed. During the 1950s, many [[Navajo Nation|Navajos]] in the U.S. became uranium miners, as many uranium deposits were discovered on Navajo [[Indian reservation|reservations]]. A statistically significant subset of these early miners later developed [[small cell carcinoma]] after exposure to uranium ore.<ref>{{Cite journal
| volume = 81
| issue = 4
| pages = 449–452
| last = Gottlieb
| first = LS
| coauthors = LA Husen
| title = Lung cancer among Navajo uranium miners
| journal = Chest
| accessdate = 2007-08-09
| date = 1982-04-01
| url = http://www.chestjournal.org/cgi/content/abstract/81/4/449
| doi = 10.1378/chest.81.4.449
}}</ref> [[Radon]]-222, a natural [[decay product]] of uranium, has been shown to be the cancer-causing agent.<ref>{{cite web
| url= http://www.rand.org/pubs/monograph_reports/MR1018.7/mr1018.7.chap2.html
| title= Chapter 2: Health Effects
| last= Harley | first= Naomi | coauthors= Ernest Foulkes, Lee H. Hilborne, Arlene Hudson, C. Ross Anthony
| year= 1999 | work= A Review of the Scientific Literature As It Pertains to Gulf War Illnesses
|publisher= [[RAND Corporation]]
|pages= Volume 7: Depleted Uranium |language= |doi= |archiveurl= |archivedate= |quote=
| accessdate= 2008-05-10 }} </ref> Some American survivors and their descendants received compensation under the [[Radiation Exposure Compensation Act]] in 1990.
In January 2008 [[Areva]] was nominated for an Anti Oscar Award.<ref>{{cite web
| url= http://www.guardian.co.uk/environment/2008/jan/22/corporatesocialresponsibility
| title= "Awards shine spotlight on big business green record"
| last= Aldred | first= Jessica | date= January 22 2008 | publisher= ''[[The Guardian]]''
| accessdate= 2008-05-10 }} </ref> The French state-owned company mines uranium in northern Niger where mine workers are not informed about health risks, and analysis shows radioactive contamination of air, water and soil.The local organization that represents the mine workers, spoke of “suspicious deaths among the workers, caused by radioactive dust and contaminated groundwater.”<ref>{{cite web
| url= http://www.foeeurope.org/activities/Nuclear/pdf/2008/Public_Eye_Denounces_Areva.pdf
| title= Public Eye Denounces Areva and Glencore, Praises Hess Natur
|author= |last= |first= |authorlink= |coauthors=
| date= January 23, 2008 | format= [[PDF]] |work= |publisher= The Public Eye Awards
| accessdate= 2008-05-10 }} </ref>
== Futher reading ==
* [http://www.wise-uranium.org/uippra.html Impacts of Uranium Mining at Port Radium, NWT, Canada].
* [http://www.wise-uranium.org/uhr.html Health Impacts for Uranium Mine and Mill Residents - Science Issues].
* [http://www.deseretnews.com/dn/sview/1,3329,250010691,00.html Uranium mining left a legacy of death].
== References ==
{{reflist}}
== See also ==
{{EnergyPortal}}
* [[JoAnn Tall]]
* [[List of uranium mines]]
* [[Peak uranium]]
* [[Radiation poisoning]]
* [[Radioactive contamination]]
* [[Uranium]]
* [[Uranium market]]
* [[Uranium metallurgy]]
* [[Uranium mining controversy in Kakadu National Park]]
* [[Uranium reserves]]
== External links ==
* [http://www.world-nuclear.org/info/inf23.html World Uranium Mining (giving production statistics)], [[World Nuclear Association]], July 2006
* [http://www.uraniumsa.org/processing/insitu_leaching.htm Further explanation of ISL]
* [http://npc.sarov.ru/english/digest/132004/appendix8.html Evaluation of Cost of Seawater Uranium Recovery and Technical Problems toward Implementation]
* {{Handbook of Texas|id=UU/dku1|name=Uranium Mining}}
* [http://www.nfb.ca/enclasse/doclens/visau/index.php?mode=view&filmId=18301&language=english&sort=title# Watch ''Uranium'', a 1990 documentary on the risks of uranium mining]
* [http://www.world-nuclear.org/info/inf75.html World Supply of Uranium] — [[World Nuclear Association]], March 2007
* [http://www.guardian.co.uk/environment/2008/jan/22/corporatesocialresponsibility The Guardian (22 Jan. 2008): ''Awards shine spotlight on big business green record'']
*[http://www.sric.org/voices/2001/v2n1/Usiberia.html Southwest Research and Information Center: ''Shedding Light on Uranium Operations in Siberia'']
*[http://pubs.acs.org/cgi-bin/abstract.cgi/esthag/2008/42/i07/abs/es702249v.html Sustainability of Uranium Mining and Milling: Toward Quantifying Resources and Eco-Efficiency]
*[http://www.azcentral.com/arizonarepublic/news/articles/0626grandcanyon.html New Uranium Mining halted at Canyon]
[[Category:Uranium mining| ]]
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