![USGS Wyoming uranium production](https://upload.wikimedia.org/wikipedia/commons/0/01/USGS_Wyoming_uranium_production.png)
Uranium mining in Wyoming was formerly a much larger industry than it is today.
Wyoming
Wyoming () is a U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho to the west, Utah to the south ...
once had many operating uranium mines, and still has the largest known uranium ore reserves of any state in the U.S. At the end of 2008, the state had estimated reserves dependent on price: 539 million pounds of uranium oxide at $50 per pound, and 1,227 million pounds at $100 per pound.
Wyoming has produced a total of 84,000
tonnes
The tonne ( or ; symbol: t) is a unit of mass equal to 1000 kilograms. It is a non-SI unit accepted for use with SI. It is also referred to as a metric ton to distinguish it from the non-metric units of the short ton ( United States ...
of uranium, and from 1995 until 2015, actually led the nation in production. Total reserves as of 2015 still amounts to 141,000 tonnes at 0.065 percent
grade
Grade most commonly refers to:
* Grade (education), a measurement of a student's performance
* Grade, the number of the year a student has reached in a given educational stage
* Grade (slope), the steepness of a slope
Grade or grading may also ref ...
. However, since the early 1990s, this production has been by the
in situ leach
In-situ leaching (ISL), also called in-situ recovery (ISR) or solution mining, is a mining process used to recover minerals such as copper and uranium through boreholes drilled into a deposit, ''in situ''. In situ leach works by artificially disso ...
method.
The Wyoming uranium mining industry was hard-hit in the 1980s by the drop in the price of uranium. When the uranium price dropped, the uranium-mining boom town of
Jeffrey City lost 95% of its population in three years.
Powder River Basin
US Geological Survey
The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, an ...
geologist
David Love discovered uranium in 1951 near Pumpkin Buttes, about 25 miles northeast of
Midwest, Wyoming
Midwest is a town in Natrona County, Wyoming, United States. It is part of the Casper, Wyoming Metropolitan Statistical Area. The population was 404 at the 2010 census.
Geography
Midwest is located at (43.408203, -106.278114).
According to t ...
. Other deposits were found along a 60-mile northwest-southeast trend in the southwest part of the
Powder River Basin
The Powder River Basin is a geologic structural basin in southeast Montana and northeast Wyoming, about east to west and north to south, known for its extensive coal reserves. The former hunting grounds of the Oglala Lakota, the area is very s ...
, and production began in 1953. The deposits are
roll fronts in fluvial sandstones of the
Eocene
The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene' ...
Wasatch Formation
The Wasatch Formation (Tw)Shroba & Scott, 2001, p.3 is an extensive highly fossiliferous geologic formation stretching across several basins in Idaho, Montana Wyoming, Utah and western Colorado.[Paleocene
The Paleocene, ( ) or Palaeocene, is a geological epoch (geology), epoch that lasted from about 66 to 56 mya (unit), million years ago (mya). It is the first epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), E ...]
Fort Union Formation
The Fort Union Formation is a geologic unit containing sandstones, shales, and coal beds in Wyoming, Montana, and parts of adjacent states. In the Powder River Basin, it contains important economic deposits of coal, uranium, and coalbed methane.
...
. The principal ore minerals are
uraninite
Uraninite, formerly pitchblende, is a radioactive, uranium-rich mineral and ore with a chemical composition that is largely UO2 but because of oxidation typically contains variable proportions of U3O8. Radioactive decay of the uranium causes t ...
,
coffinite
Coffinite is a uranium-bearing silicate mineral with formula: U(SiO4)1−x(OH)4x.
It occurs as black incrustations, dark to pale-brown in thin section. It has a grayish-black streak. It has a brittle to conchoidal fracture. The hardness of coffini ...
,
metatyuyamunite, and
carnotite
Carnotite is a potassium uranium vanadate radioactive mineral with chemical formula K2( U O2)2( VO4)2·3 H2O. The water content can vary and small amounts of calcium, barium, magnesium, iron, and sodium are often present.
Occurrence
Carnotite i ...
. Gangue minerals are
calcite
Calcite is a Carbonate minerals, carbonate mineral and the most stable Polymorphism (materials science), polymorph of calcium carbonate (CaCO3). It is a very common mineral, particularly as a component of limestone. Calcite defines hardness 3 on ...
,
gypsum
Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula . It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, blackboard or sidewalk chalk, and drywall. ...
,
pyrite
The mineral pyrite (), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Iron, FeSulfur, S2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral.
Pyrite's metallic Luster (mineralogy), lust ...
, iron oxide, and
barite
Baryte, barite or barytes ( or ) is a mineral consisting of barium sulfate ( Ba S O4). Baryte is generally white or colorless, and is the main source of the element barium. The ''baryte group'' consists of baryte, celestine (strontium sulfate), ...
.
Northern Black Hills
Uranium
Uranium is a chemical element with the symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium is weak ...
was discovered in 1952 in
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of th ...
sandstones of the
Inyan Kara Group
The Inyan Kara Group is a geologic group classification applied in South Dakota and adopted in portions of Wyoming and Montana. It preserves fossils of the mid-Cretaceous period. Of late Albian age, this classification correlates with the lower Da ...
near its outcrop in
Crook County, Wyoming
Crook County is a county in the northeastern section of the U.S. state of Wyoming. As of the 2020 United States Census, the population was 7,181, making it the third-least populous county in Wyoming. Its county seat is Sundance.
History
Croo ...
, near the northeast edge of the
Black Hills
The Black Hills ( lkt, Ȟe Sápa; chy, Moʼȯhta-voʼhonáaeva; hid, awaxaawi shiibisha) is an isolated mountain range rising from the Great Plains of North America in western South Dakota and extending into Wyoming, United States. Black Elk P ...
. Production began in 1953. Ore minerals are
uraninite
Uraninite, formerly pitchblende, is a radioactive, uranium-rich mineral and ore with a chemical composition that is largely UO2 but because of oxidation typically contains variable proportions of U3O8. Radioactive decay of the uranium causes t ...
and
coffinite
Coffinite is a uranium-bearing silicate mineral with formula: U(SiO4)1−x(OH)4x.
It occurs as black incrustations, dark to pale-brown in thin section. It has a grayish-black streak. It has a brittle to conchoidal fracture. The hardness of coffini ...
in unoxidized
sandstone
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks.
Most sandstone is composed of quartz or feldspar (both silicates) ...
, and
carnotite
Carnotite is a potassium uranium vanadate radioactive mineral with chemical formula K2( U O2)2( VO4)2·3 H2O. The water content can vary and small amounts of calcium, barium, magnesium, iron, and sodium are often present.
Occurrence
Carnotite i ...
and
tyuyamunite
Tyuyamunite (pronounced tuh-YOO-ya-moon-ite) is a very rare uranium mineral with formula Ca(UO2)2V2O8·(5-8)H2O. It is a member of the carnotite group. It is a bright, canary-yellow color because of its high uranium content. Also, because of tyuyam ...
in oxidized sandstone.
Gangue
In mining, gangue () is the commercially worthless material that surrounds, or is closely mixed with, a wanted mineral in an ore deposit. It is thus distinct from overburden, which is the waste rock or materials overlying an ore or mineral body t ...
minerals in unoxidized deposits are
pyrite
The mineral pyrite (), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Iron, FeSulfur, S2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral.
Pyrite's metallic Luster (mineralogy), lust ...
,
marcasite
The mineral marcasite, sometimes called “white iron pyrite”, is iron sulfide (FeS2) with orthorhombic crystal structure. It is physically and crystallographically distinct from pyrite, which is iron sulfide with cubic crystal structure. Both ...
, and
calcite
Calcite is a Carbonate minerals, carbonate mineral and the most stable Polymorphism (materials science), polymorph of calcium carbonate (CaCO3). It is a very common mineral, particularly as a component of limestone. Calcite defines hardness 3 on ...
; in oxidized deposits
calcite
Calcite is a Carbonate minerals, carbonate mineral and the most stable Polymorphism (materials science), polymorph of calcium carbonate (CaCO3). It is a very common mineral, particularly as a component of limestone. Calcite defines hardness 3 on ...
and iron oxide.
No mining has taken place in the Northern Black Hills district in recent years, but recent high uranium prices have brought new exploration drilling to the are
Gas Hills
The
Gas Hills
Gas is one of the four fundamental state of matter, states of matter (the others being solid, liquid, and plasma (physics), plasma).
A pure gas may be made up of individual atoms (e.g. a noble gas like neon), chemical element, elemental molec ...
district, straddling the
Natrona-
Fremont county line in central Wyoming, was discovered on 9 Sept. 1953 by Neil McNeice, which led to the development of the Luck Mc Mine and others, with ore production beginning in 1955. The ore consisted of lenticular bodies of
meta-autunite,
uraninite
Uraninite, formerly pitchblende, is a radioactive, uranium-rich mineral and ore with a chemical composition that is largely UO2 but because of oxidation typically contains variable proportions of U3O8. Radioactive decay of the uranium causes t ...
, and
coffinite
Coffinite is a uranium-bearing silicate mineral with formula: U(SiO4)1−x(OH)4x.
It occurs as black incrustations, dark to pale-brown in thin section. It has a grayish-black streak. It has a brittle to conchoidal fracture. The hardness of coffini ...
in fluvial
arkosic
Arkose () or arkosic sandstone is a detrital sedimentary rock, specifically a type of sandstone containing at least 25% feldspar.
Arkosic sand is sand that is similarly rich in feldspar, and thus the potential precursor of arkose.
Quartz is c ...
sandstone
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks.
Most sandstone is composed of quartz or feldspar (both silicates) ...
s in the upper
Wind River Formation
The Wind River Formation is a geologic formation in Wyoming. It preserves fossils dating back to the Paleogene period. A recent study by Stanford suggests that fracking has contaminated the entire ground water resource in the basin.
Fossil conte ...
of
Eocene
The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene' ...
age. Mining was mostly by open pit, although there were also some underground mines. Strathmore Minerals Corp. of
Kelowna, British Columbia
Kelowna ( ) is a city on Okanagan Lake in the Okanagan Valley in the southern interior of British Columbia, Canada. It serves as the head office of the Regional District of Central Okanagan. The name Kelowna derives from the Okanagan word ''ki ...
is currently applying for permits to mine properties in the Gas Hills distric
ref name="Heinrich">
Little Mountain district
In the Little Mountain mining district on the west side of the
Bighorn Mountains
The Bighorn Mountains ( cro, Basawaxaawúua, lit=our mountains or cro, Iisaxpúatahchee Isawaxaawúua, label=none, lit=bighorn sheep's mountains) are a mountain range in northern Wyoming and southern Montana in the United States, forming a nort ...
,
Big Horn County, Wyoming
Big Horn County is a county in the U.S. state of Wyoming. As of the 2020 United States Census, the population was 11,521. The county seat is Basin. Its north boundary abuts the south boundary of Montana.
History
Big Horn County was created by ...
, uranium was produced from 1955 to 1970 from paleokarst
breccia
Breccia () is a rock composed of large angular broken fragments of minerals or rocks cemented together by a fine-grained matrix.
The word has its origins in the Italian language, in which it means "rubble". A breccia may have a variety of di ...
s in the
Madison Limestone
The Madison Limestone is a thick sequence of mostly carbonate rocks of Mississippian age in the Rocky Mountain and Great Plains areas of the western United States. The rocks serve as an important aquifer as well as an oil reservoir in places. Th ...
of
Mississippian age. The uranium occurs as
carnotite
Carnotite is a potassium uranium vanadate radioactive mineral with chemical formula K2( U O2)2( VO4)2·3 H2O. The water content can vary and small amounts of calcium, barium, magnesium, iron, and sodium are often present.
Occurrence
Carnotite i ...
and
tyuyamunite
Tyuyamunite (pronounced tuh-YOO-ya-moon-ite) is a very rare uranium mineral with formula Ca(UO2)2V2O8·(5-8)H2O. It is a member of the carnotite group. It is a bright, canary-yellow color because of its high uranium content. Also, because of tyuyam ...
.
Shirley Basin
![USGS Wyoming Shirley Basin uranium](https://upload.wikimedia.org/wikipedia/commons/5/5e/USGS_Wyoming_Shirley_Basin_uranium.png)
Uranium was discovered in the
Shirley Basin
Shirley may refer to:
Arts and entertainment
* ''Shirley'' (novel), an 1849 novel by Charlotte Brontë
* ''Shirley'' (1922 film), a British silent film
* ''Shirley'' (2020 film), an American film
* ''Shirley'' (album), a 1961 album by Shirley Bas ...
,
Carbon County, in 1955. Production began in 1960 from underground and open-pit mines. Mining by
in-situ leaching
In-situ leaching (ISL), also called in-situ recovery (ISR) or solution mining, is a mining process used to recover minerals such as copper and uranium through boreholes drilled into a deposit, ''in situ''. In situ leach works by artificially disso ...
began in 1961, the first in-situ leach mining of uranium in the United States. The ore occurs as roll fronts in
Eocene
The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene' ...
sandstone of the
Wind River Formation
The Wind River Formation is a geologic formation in Wyoming. It preserves fossils dating back to the Paleogene period. A recent study by Stanford suggests that fracking has contaminated the entire ground water resource in the basin.
Fossil conte ...
, as
uraninite
Uraninite, formerly pitchblende, is a radioactive, uranium-rich mineral and ore with a chemical composition that is largely UO2 but because of oxidation typically contains variable proportions of U3O8. Radioactive decay of the uranium causes t ...
with
pyrite
The mineral pyrite (), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Iron, FeSulfur, S2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral.
Pyrite's metallic Luster (mineralogy), lust ...
,
marcasite
The mineral marcasite, sometimes called “white iron pyrite”, is iron sulfide (FeS2) with orthorhombic crystal structure. It is physically and crystallographically distinct from pyrite, which is iron sulfide with cubic crystal structure. Both ...
,
hematite
Hematite (), also spelled as haematite, is a common iron oxide compound with the formula, Fe2O3 and is widely found in rocks and soils. Hematite crystals belong to the rhombohedral lattice system which is designated the alpha polymorph of . ...
,
calcite
Calcite is a Carbonate minerals, carbonate mineral and the most stable Polymorphism (materials science), polymorph of calcium carbonate (CaCO3). It is a very common mineral, particularly as a component of limestone. Calcite defines hardness 3 on ...
, and organic matter.
Crooks Gap district
![USGS Wyoming Crooks Gap Green Mountain uranium](https://upload.wikimedia.org/wikipedia/commons/a/a5/USGS_Wyoming_Crooks_Gap_Green_Mountain_uranium.png)
The Crooks Gap district of
Fremont County contains uranium ore in fluvial sandstones of the
Eocene
The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene' ...
Battle Spring Formation. Most uranium deposits are in the Wasatch, with ore zones containing uraninite and pyrite. Oxidized ores include
uranophane
Uranophane ( Ca( U O2)2( SiO3O H)2·5 H2O), also known as uranotile, is a rare calcium uranium silicate hydrate mineral that forms from the oxidation of other uranium-bearing minerals. It has a yellow color and is radioactive.
Alice Mary Weeks, a ...
, meta-
autunite
Autunite (hydrated calcium uranyl phosphate), with formula Ca(UO2)2(PO4)2·10–12H2O, is a yellow-greenish fluorescent phosphate mineral with a hardness of 2–. Autunite crystallizes in the orthorhombic system and often occurs as tabular square ...
, and
phosphuranylite
Phosphuranylite is a uranyl phosphate mineral with formula KCa(H3O)3(UO2)7(PO4)4O4·8(H2O).
It was first described in 1879 by Frederick Augustus Genth, from an occurrence in the Flat Rock pegmatite in Mitchell County, North Carolina
Mitchell ...
.
[
]
Current Activity
By 2006, the only active uranium mine in Wyoming was the Smith Ranch-Highland
Smith Ranch and Highland are uranium mining operations located in Wyoming, United States, U.S.A. They are separate permits, operated as a single operation, and have one central processing facility. The Smith Ranch-Highland operation is the largest ...
in-situ leaching
In-situ leaching (ISL), also called in-situ recovery (ISR) or solution mining, is a mining process used to recover minerals such as copper and uranium through boreholes drilled into a deposit, ''in situ''. In situ leach works by artificially disso ...
operation in the Powder River Basin
The Powder River Basin is a geologic structural basin in southeast Montana and northeast Wyoming, about east to west and north to south, known for its extensive coal reserves. The former hunting grounds of the Oglala Lakota, the area is very s ...
, owned by Power Resources, Inc., a subsidiary of Cameco
Cameco Corporation (formerly Canadian Mining and Energy Corporation) is the world's largest publicly traded uranium company, based in Saskatoon, Saskatchewan, Canada. In 2015, it was the world's second largest uranium producer, accounting for 18 ...
. The mine produced 907 tonnes of yellowcake
Yellowcake (also called urania) is a type of uranium concentrate powder obtained from leach solutions, in an intermediate step in the processing of uranium ores. It is a step in the processing of uranium after it has been mined but before fue ...
(uranium oxide concentrate, U3O8) in 2006, making it the leading uranium producer in the United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...
.
In October 2007, Energy Metals Corp. applied for a Nuclear Regulatory Commission
The Nuclear Regulatory Commission (NRC) is an independent agency of the United States government tasked with protecting public health and safety related to nuclear energy. Established by the Energy Reorganization Act of 1974, the NRC began operat ...
(NRC) permit to start an in-situ leach
In-situ leaching (ISL), also called in-situ recovery (ISR) or solution mining, is a mining process used to recover minerals such as copper and uranium through boreholes drilled into a deposit, ''in situ''. In situ leach works by artificially disso ...
mine at the Moore Ranch deposit in Campbell County in the Powder River Basin
The Powder River Basin is a geologic structural basin in southeast Montana and northeast Wyoming, about east to west and north to south, known for its extensive coal reserves. The former hunting grounds of the Oglala Lakota, the area is very s ...
. Energy Metals is a subsidiary of Uranium One
Uranium One is an international group of companies, part of the management circuit of the TENEX Group of Rosatom State Corporation. Since 2013, it is a wholly owned subsidiary of Moscow-based Uranium One Group, a part of the Russian state-owned nu ...
. The permit application is the first NRC application since 1988 for a new uranium recovery facility. The Moore Ranch deposit contains an estimated 5.8 million pounds (2600 tonnes) of uranium oxide. The uranium will be absorbed onto ion-exchange resin beads at the mine; the beads will be shipped to existing facilities of Power Resources Inc. (Cameco
Cameco Corporation (formerly Canadian Mining and Energy Corporation) is the world's largest publicly traded uranium company, based in Saskatoon, Saskatchewan, Canada. In 2015, it was the world's second largest uranium producer, accounting for 18 ...
) in Wyoming
Wyoming () is a U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho to the west, Utah to the south ...
and Nebraska
Nebraska () is a state in the Midwestern region of the United States. It is bordered by South Dakota to the north; Iowa to the east and Missouri to the southeast, both across the Missouri River; Kansas to the south; Colorado to the southwe ...
for recovery of the uranium.
In September 2014, Uranerz Energy shipped the first uranium concentrate from its Nichols Ranch mine in the Powder River Basin. Nichols Ranch is an in-situ leach mine, using oxygenated water and sodium bicarbonate to dissolve the uranium. The uranium is recovered at the surface onto resin beads by ion exchange. The resin beads are shipped to Cameco's Smith Ranch mill, where the uranium is recovered. Uranerz expects to produce 300,000 to 400,000 pounds of uranium concentrate in 2014.["Uranerz delivers first Nichols Ranch uranium to utilities," ''Engineering & Mining Journal'', Oct. 2014, p.8.]
See also
* High Plains Uranium
*Uranium mining
Uranium mining is the process of extraction of uranium ore from the ground. Over 50 thousand tons of uranium were produced in 2019. Kazakhstan, Canada, and Australia were the top three uranium producers, respectively, and together account f ...
*Uranium mining in the United States
Uranium mining in the United States produced of U3O8 in 2019, 88% lower than the 2018 production of of U3O8 and the lowest US annual production since 1948. The 2019 production represents 0.3% of the anticipated uranium fuel requirements of t ...
*List of uranium mines
Uranium production is carried out in about 13 countries around the world, in 2017 producing a cumulative total of 59,462 tonnes of uranium (tU). The international producers were Kazakhstan (39%), Canada (22%), Australia (10%), Namibia (7.1%), Nig ...
Citations
External links
Wyoming Geological Survey: Uranium Page
Wyoming Department of Environmental Quality: Uranium Mill Tailing Cleanup Program FAQs
{{Uranium mining
Wyoming
Wyoming () is a U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho to the west, Utah to the south ...
Mining in Wyoming
Geology of Wyoming
Geology of the Rocky Mountains