Uranium mining in the United States produced of U3O8 in 2023, 15% of the 2018 production of of U3O8. The 2023 production represents 0.4% of the uranium fuel requirements of the US's nuclear power reactors for the year. Production came from five in-situ leaching plants, four in Wyoming (Nichols Ranch ISR Project, Lance Project, Lost Creek Project, and Smith Ranch-Highland Operation) and one in Nebraska (Crowe Butte Operation); and from the White Mesa conventional mill in Utah.
From 1949 to 2019, total US production of uranium oxide (U3O8) was 979.9 million pounds (444,500 tonnes).
History While uranium is used primarily for nuclear power, uranium mining had its roots in the production of radium-bearing ore from 1898 from the mining of uranium-vanadium sandstone deposits in western Colorado. The 1950s saw a boom in uranium mining in the western U.S., spurred by the fortunes made by prospectors such as Charlie Steen. The United States was the world's leading producer of uranium from 1953 until 1980. In 1980 annual U.S. production peaked at 43.7 million pounds of U3O8. Until the early 1980s, there were active uranium mines in Arizona, Colorado, New Mexico, Oregon, South Dakota, Texas, Utah, Washington and Wyoming.
Price declines in the late 1970s and early 1980s forced the closure of numerous mines. 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 late 1970s. By 2001, there were only three operating uranium mines (all in-situ leaching operations) in the United States. Annual production reached a low of 779 metric tons of uranium oxide in 2003, but then more than doubled in three years to 1672 metric tons in 2006, from 10 mines. The U.S. DOE's Energy Information Administration reported that 90% of U.S. uranium production in 2006 came from in-situ leaching.U.S. Energy Information Administration: U.S. uranium mine production and number of mines and sources, accessed 6 March 2009.
The average spot price of uranium oxide (U3O8) increased from $7.92 per pound in 2001 to $39.48 per pound ($/kg) in 2006.Department of Energy's Energy Information Administration data, official energy statistics from the U.S. Government In 2011 the United States mined 9% of the uranium consumed by its nuclear power plants.US Energy Information Administration, Where our uranium comes from, 2 July 2012. The remainder was imported, principally from Russia and Kazakhstan (38%), Canada, and Australia.Warren I Finch (2003) Uranium-fuel for nuclear energy 2002, US Geological Survey, Bulletin 2179-A.See S&TR: September 2005, How One Equation Changed the World, which discusses the progress of the HEU Purchase Agreement made between the Russian Federation and the United States in 1993. "Currently, Russian plants are processing about 30 metric tons of HEU per year into about 875 metric tons of LEU. This amount meets half the annual fuel requirement for U.S. nuclear power plants and provides the fuel to generate 10 percent of the electricity used in the U.S." Although uranium production has declined to low levels, the United States has the fourth-largest uranium resource in the world, behind Australia, Canada, and Kazakhstan. United States uranium reserves are strongly dependent on price. At $50 per pound U3O8, reserves are estimated to be 539 million pounds; however, at a price of $100 per pound, reserves are an estimated 1227 million pounds.US Energy Information Administration, U.S. uranium reserves estimates, July 2010. Rising uranium prices since 2001 have increased interest in uranium mining in Arizona, Colorado, Texas and Utah.WISE Uranium Project: New uranium mining projects – USA, accessed 25 March 2009. The states with the largest known uranium ore reserves (not counting byproduct uranium from phosphate) are (in order) Wyoming, New Mexico, and Colorado.J. Keller and others, Colorado, Mining Engineering, May 2006, p. 76.
The radiation hazards of uranium mining and milling were not appreciated in the early years thereod, resulting in workers being exposed to high levels of radiation. Radon gas is a colorless, odorless, radioactive gas that forms naturally from the decay of radioactive elements like uranium, found in rocks and soil. Inhalation of radon gas caused sharp, consistent increases in lung cancers among underground uranium miners employed in the 1940s and 1950s. In 1950, the US Public Health service began a comprehensive study of uranium miners, leading to the first publication of a statistical correlation between cancer and uranium mining, released in 1962.Dawson, Susan E, and Gary E Madsen. "Uranium Mine Workers, Atomic Downwinders, and the Radiation Exposure Compensation Act." In Half Lives & Half-Truths: Confronting the Radioactive Legacies of the Cold War, 117–143. Santa Fe: School For Advanced Research, 2007) In 1969, the federal government regulated the standard amount of radon in mines.Brugge, Doug, Timothy Benally, and Esther Yazzie-Lewis. The Navajo People and Uranium Mining. Albuquerque : University of New Mexico Press, 2006. In 1990, Congress passed the Radiation Exposure Compensation Act (RECA), granting compensation for those affected by mining. Out of 50 present and former uranium milling sites in 12 states, 24 have been abandoned and are the responsibility of the US Department of Energy.
By state
Alabama Uranium in Alabama is found in the Coosa Block of the Northern Alabama Piedmont. Metamorphic uranium occurrences have been found in the Higgins Ferry Group in Coosa and Clay Counties. Some exploration has been done, but no economic deposits have been found to date.
Alaska Alaska's only uranium mine, Ross-Adams, was discovered in 1955 by an airborne gamma radiation survey. The deposit is on the side of Bokan Mountain on Prince of Wales Island. The principal ore mineral is uranothorite, which occurs in veinlets in granite. Accessory minerals are primarily hematite and calcite, with lesser amounts of fluorite, pyrite, galena, quartz, and rare earth minerals. Mining commenced in 1957, when approximately 18,000 tonnes of thorium-bearing uranium ore grading 1% U3O8 was recovered from an open pit. Additional mining took place in 1961–1962 (6800 tonnes of ore), 1963 (10,880 tonnes), and 49,885 tonnes from 1968–1971 from underground operations.E.M. MacKevett Jr. (1963) Geology and Ore Deposits of the Bokan Mountain Uranium-Thorium Area, Southeastern Alaska, US Geological Survey, Bulletin 1154. A total of 1.3 million pounds of U3O8 at a grade of 0.76% was produced from open pit and underground operations, with milling taking place in Washington and Utah.
Arizona
Uranium mining in Arizona has taken place since 1918. Prior to the uranium boom of the late 1940s, uranium in Arizona was a byproduct of vanadium mining of the mineral carnotite.
California Uranium was discovered in 1954 in the Sierra Nevada of Kern County, along the Kern River about northeast of Bakersfield. Two mines, the Kergon mine and the Miracle mine, made small shipments in 1954 and 1955. Uranium occurs as uraninite and autunite in shear zones in granodiorite. Accessory minerals include fluorite and the molybdenum minerals ilsemannite and jordisite.E.M. MacKevett Jr. (1960) Geology and Ore Deposits of the Kern River Uranium Area, California, US Geological Survey, Bulletin 1087-F.
Colorado
The first uranium identified in the US was pitchblende from the Wood gold mine at Central City, Colorado in 1871. Uranium mining in southwest Colorado goes back to 1898. The Uravan district of Colorado and Utah supplied about half the world's radium from 1910 to 1922, and vanadium and uranium were byproducts. The last producing uranium mine in the state, the Topaz Mine, part of the Sunday Complex near Uravan, Colorado, was closed down on March 18, 2009, by then owner Denison Mines due to depressed uranium prices. On July 6, 2021 Western Uranium & Vanadium Corp announced the resumption of mining activities at the Sunday Mine Complex. On February 14, 2022 Western Uranium & Vanadium Corp announced 2,000 tons of new production was moved into four separate underground stockpiles.J. Burnell and others, Colorado, Mining Engineering, May 2007, p. 77.
Florida The Central Florida (Bone Valley) phosphorite deposits are considered to contain the largest known uranium resource (one million metric tons of uranium oxide) in North America (but note that resources are not the same as ore reserves). Uranium has been produced as a byproduct of phosphate mining and the production of phosphoric acid fertilizer. The uranium is contained in the phosphate minerals francolite, crandallite, millisite, wavellite, and vivianite, found in Miocene and Pliocene sediments of the Bone Valley Formation. The average uranium content is 0.009%, which is considered to be low grade. Concentrations of uranium in this type of deposit typically grade to 0.01–0.015% U3O8.Warren I. Finch (1996) Uranium provinces of North America-their definition, distribution, and models, US Geological Survey, Bulletin 2141. Recovery process costs are estimated at $22 to $54 per pound of U3O8; higher than the market price of uranium during the 25-year period spanning the 1980s through the early first decade of the 21st century. Consequently, uranium recovery from Florida phosphate ceased in 1998.Energy Information Administration (12 Feb. 2008): 4th Quarter 2007 uranium production was 1.2 million pounds
Idaho From 1955 to 1960, uranium was extracted from placer black sand deposits derived from the Idaho Batholith in southwest Idaho. The deposits were mined for uranium, thorium, and rare earths. Uranium and thorium were in the monazite grains; rare earths were in columbite and euxenite. Production was 365,000 pounds (165 metric tons) of U3O8.Energy Information Administration: Lowman mill and disposal site
Uranium was mined at the Stanley district in Custer County, Idaho from 1957 to 1962. Deposits occur as veins in granite of the Cretaceous Idaho Batholith, and in strataform deposits in possibly Paleocene arkosic conglomerates and sandstones between the underlying Idaho Batholith and overlying Challis Volcanic Group (Eocene). The USGS has estimated production to be less than 170,000 pounds (78 metric tons) of U3O8.Bradley S. Van Gosen and others (2005) A Reconnaissance Geochemical and Mineralogical Study of the Stanley Uranium District, Custer County, Central Idaho, US Geological Survey, Scientific Investigations Report 2005-5264.
Nebraska
The only operating uranium mine in Nebraska is the Crow Butte mine, operated by Cameco. The mine is southeast of Crawford in Dawes County, western Nebraska.R.M. Lyman, Wyoming, Mining Engineering, May 2005 p. 130. The roll-front deposit in the Oligocene Chadron formation was discovered in 1980 by Wyoming Fuel Co. Commercial operation began in 1991. Uranium is mined by in-situ leaching which involves the extraction by boreholes of uranium-bearing (U3O8) water, which is then filtered through resin beads. Through an ion exchange process, the resin beads attract uranium from the solution. Uranium loaded resins are then transported to a processing plant, where U3O8 is separated from the resin beads and yellowcake is produced. The resin beads are returned to the ion exchange facility where they are reused.Nuclear Regulatory Commission (13 Feb. 1998): Crow Butte resources Inc., Final finding of no significant impact
Nevada