Uranium mining in the United States produced 3,303,977 pounds (1,498,659 kg) of U3O8 (1271 tonnes of uranium) in 2015, 32% lower than 2014's production of 4,891,332 pounds (2,218,671 kg) of U3O8 (1881 tonnes of uranium) and the lowest US annual production since 2005. The 2015 production represents 7% of the anticipated uranium market requirements of the USA's nuclear power reactors for the year.[1]
Production came from one conventional uranium mill in Utah, and six in-situ leach operations: four in Wyoming, one in Texas and one in Nebraska.[2]
While uranium is used primarily for nuclear power, uranium mining had its roots in the production of uranium-bearing ore in 1898 with the mining of carnotite-bearing sandstones of the Colorado Plateau in Colorado and Utah, for their vanadium content. The late 1940s and early 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, when annual U.S. production peaked at 16,810 metric tons U3O8.[3] Until the early 1980s, there were active uranium mines in Arizona, Colorado, New Mexico, South Dakota, Texas, Utah, Washington, and Wyoming.[4]
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.[5] The U.S. DOE's Energy Information Administration reported that 90% of U.S. uranium production in 2006 came from in-situ leaching.[6]
The average spot price of uranium oxide (U3O8) increased from $7.92 per pound in 2001 to $39.48 per pound ($87.04/kg) in 2006.[7] In 2011 the United States mined 9% of the uranium consumed by its nuclear power plants.[8] The remainder was imported, principally from Russia and Kazakhstan (38%), Canada, and Australia.[9][10][11] 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.[10] 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.[12] Rising uranium prices since 2001 have increased interest in uranium mining in Arizona, Colorado, Texas and Utah.[13][14] The states with the largest known uranium ore reserves (not counting byproduct uranium from phosphate) are (in order) Wyoming, New Mexico, and Colorado.[15]
The radiation hazards of uranium mining and milling were not appreciated in the early years, resulting in workers being exposed to high levels of radiation. Inhalation of radon gas caused sharp increases in lung cancers among underground uranium miners employed in the 1940s and 1950s.[16][17][18] 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.[19] In 1969, the federal government regulated the standard amount of radonin mines.[20] In 1990, Congress passed the Radiation Exposure Compensation Act (RECA), granting reparations for those affected by mining.[19] 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.[21]
