Uranium mining in Wyoming
Encyclopedia
Uranium mining in Wyoming, a state of the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 was formerly a much larger industry than it is today. Wyoming
Wyoming
Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...

 once had many operating uranium mines, and still has the largest known uranium ore reserves of any state in the U.S. 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
Jeffrey City, Wyoming
Jeffrey City is a census-designated place and former uranium mining boomtown located in Fremont County, in the central part of the U.S. state of Wyoming. The town is famous in Wyoming and the American West as symbol of a boomtown that went “bust” very quickly, as the mine was shut down in 1982...

 lost 95% of its population in three years.

Powder River Basin

US Geological Survey geologist J. D. Love discovered uranium in 1951 near Pumpkin Buttes, about 25 miles northeast of Midwest, Wyoming
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 408 at the 2000 census.-Geography:Midwest is located at ....

. Other deposits were found along a 60-mile northwest-southeast trend in the southwest part of the Powder River Basin
Powder River Basin
The Powder River Basin is a geologic region in southeast Montana and northeast Wyoming, about east to west and north to south, known for its coal deposits. The region supplies about 40 percent of coal in the United States. It is both a topographic drainage and geologic structural basin...

, and production began in 1953. The deposits are roll fronts in fluvial sandstones of the Eocene
Eocene
The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...

 Wasatch Formation and underlying Paleocene
Paleocene
The Paleocene or Palaeocene, the "early recent", is a geologic epoch that lasted from about . It is the first epoch of the Palaeogene Period in the modern Cenozoic Era...

 Fort Union Formation
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
Uraninite is a radioactive, uranium-rich mineral and ore with a chemical composition that is largely UO2, but also contains UO3 and oxides of lead, thorium, and rare earth elements...

, coffinite
Coffinite
Coffinite is a uranium-bearing silicate mineral with formula: U1-x4x.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 coffinite is between 5 and 6.It was first described in 1954 for an...

, metatyuyamunite, and carnotite
Carnotite
Carnotite is a potassium uranium vanadate radioactive mineral with chemical formula: K222·3H2O. The water content can vary and small amounts of calcium, barium, magnesium, iron, and sodium are often present.-Occurrence:...

. Gangue minerals are calcite
Calcite
Calcite is a carbonate mineral and the most stable polymorph of calcium carbonate . The other polymorphs are the minerals aragonite and vaterite. Aragonite will change to calcite at 380-470°C, and vaterite is even less stable.-Properties:...

, gypsum
Gypsum
Gypsum is a very soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO4·2H2O. It is found in alabaster, a decorative stone used in Ancient Egypt. It is the second softest mineral on the Mohs Hardness Scale...

, pyrite
Pyrite
The mineral pyrite, or iron pyrite, is an iron sulfide with the formula FeS2. This mineral's metallic luster and pale-to-normal, brass-yellow hue have earned it the nickname fool's gold because of its resemblance to gold...

, iron oxide, and barite
Barite
Baryte, or barite, is a mineral consisting of barium sulfate. The baryte group consists of baryte, celestine, anglesite and anhydrite. Baryte itself is generally white or colorless, and is the main source of barium...

.

Northern Black Hills

Uranium
Uranium
Uranium is a silvery-white metallic chemical element in the actinide series of the periodic table, with atomic number 92. It is assigned the chemical symbol U. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons...

 was discovered in 1952 in Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

 sandstones of the Inyan Kara Group near its outcrop in Crook County, Wyoming, near the northeast edge of the Black Hills
Black Hills
The Black Hills are a small, isolated mountain range rising from the Great Plains of North America in western South Dakota and extending into Wyoming, USA. Set off from the main body of the Rocky Mountains, the region is something of a geological anomaly—accurately described as an "island of...

. Production began in 1953. Ore minerals are uraninite
Uraninite
Uraninite is a radioactive, uranium-rich mineral and ore with a chemical composition that is largely UO2, but also contains UO3 and oxides of lead, thorium, and rare earth elements...

 and coffinite
Coffinite
Coffinite is a uranium-bearing silicate mineral with formula: U1-x4x.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 coffinite is between 5 and 6.It was first described in 1954 for an...

 in unoxidized sandstone
Sandstone
Sandstone is a sedimentary rock composed mainly of sand-sized minerals or rock grains.Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any colour, but the most common colours are tan, brown, yellow,...

, and carnotite
Carnotite
Carnotite is a potassium uranium vanadate radioactive mineral with chemical formula: K222·3H2O. The water content can vary and small amounts of calcium, barium, magnesium, iron, and sodium are often present.-Occurrence:...

 and tyuyamunite in oxidized sandstone. Gangue
Gangue
In mining, gangue is the commercially worthless material that surrounds, or is closely mixed with, a wanted mineral in an ore deposit. The separation of mineral from gangue is known as mineral processing, mineral dressing or ore dressing and it is a necessary and often significant aspect of mining...

 minerals in unoxidized deposits are pyrite
Pyrite
The mineral pyrite, or iron pyrite, is an iron sulfide with the formula FeS2. This mineral's metallic luster and pale-to-normal, brass-yellow hue have earned it the nickname fool's gold because of its resemblance to gold...

, marcasite
Marcasite
The mineral marcasite, sometimes called white iron pyrite, is iron sulfide with orthorhombic crystal structure. It is physically and crystallographically distinct from pyrite, which is iron sulfide with cubic crystal structure. Both structures do have in common that they contain the disulfide...

, and calcite
Calcite
Calcite is a carbonate mineral and the most stable polymorph of calcium carbonate . The other polymorphs are the minerals aragonite and vaterite. Aragonite will change to calcite at 380-470°C, and vaterite is even less stable.-Properties:...

; in oxidized deposits calcite
Calcite
Calcite is a carbonate mineral and the most stable polymorph of calcium carbonate . The other polymorphs are the minerals aragonite and vaterite. Aragonite will change to calcite at 380-470°C, and vaterite is even less stable.-Properties:...

 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 area.http://www.powertechuranium.com/s/NewsReleases.asp?ReportID=201275&_Type=News-Releases&_Title=Aladdin-Project-Drilling-Update

Gas Hills

The Gas Hills district, straddling the Natrona-Fremont county line in central Wyoming, was discovered in 1953, and ore production began in 1955. The ore consisted of lenticular bodies of meta-autunite, uraninite
Uraninite
Uraninite is a radioactive, uranium-rich mineral and ore with a chemical composition that is largely UO2, but also contains UO3 and oxides of lead, thorium, and rare earth elements...

, and coffinite
Coffinite
Coffinite is a uranium-bearing silicate mineral with formula: U1-x4x.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 coffinite is between 5 and 6.It was first described in 1954 for an...

 in fluvial arkosic
Arkose
Arkose 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....

 sandstone
Sandstone
Sandstone is a sedimentary rock composed mainly of sand-sized minerals or rock grains.Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any colour, but the most common colours are tan, brown, yellow,...

s in the upper Wind River Formation of Eocene
Eocene
The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...

 age. Mining was mostly by open pit, although there were also some underground mines. Strathmore Minerals Corp. of Kelowna, British Columbia
Kelowna, British Columbia
Kelowna is a city on Okanagan Lake in the Okanagan Valley, in the southern interior of British Columbia, Canada. Its name derives from a Okanagan language term for "grizzly bear"...

 is currently applying for permits to mine properties in the Gas Hills district.http://www.strathmoreminerals.com/s/GasHills.asp

Little Mountain district

In the Little Mountain mining district on the west side of the Bighorn Mountains, Big Horn County, Wyoming, uranium was produced from 1955 to 1970 from paleokarst breccia
Breccia
Breccia is a rock composed of broken fragments of minerals or rock cemented together by a fine-grained matrix, that can be either similar to or different from the composition of the fragments....

s in the Madison Limestone
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 western United States. The rocks serve as an important aquifer as well as an oil reservoir in places...

 of Mississippian age. The uranium occurs as carnotite
Carnotite
Carnotite is a potassium uranium vanadate radioactive mineral with chemical formula: K222·3H2O. The water content can vary and small amounts of calcium, barium, magnesium, iron, and sodium are often present.-Occurrence:...

 and tyuyamunite.

Shirley Basin

Uranium was discovered in the Shirley Basin, Carbon County
Carbon County, Wyoming
Carbon County is a county located in the U.S. state of Wyoming. As of 2010, the population was 15,885. Its county seat is Rawlins.- History :Carbon County was organized in 1868....

, in 1955. Production began in 1960 from underground and open-pit mines. Mining by in-situ leaching began in 1961, the first in-situ leach mining of uranium in the United States. The ore occurs as roll fronts in Eocene
Eocene
The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...

 sandstone of the Wind River Formation, as uraninite
Uraninite
Uraninite is a radioactive, uranium-rich mineral and ore with a chemical composition that is largely UO2, but also contains UO3 and oxides of lead, thorium, and rare earth elements...

 with pyrite
Pyrite
The mineral pyrite, or iron pyrite, is an iron sulfide with the formula FeS2. This mineral's metallic luster and pale-to-normal, brass-yellow hue have earned it the nickname fool's gold because of its resemblance to gold...

, marcasite
Marcasite
The mineral marcasite, sometimes called white iron pyrite, is iron sulfide with orthorhombic crystal structure. It is physically and crystallographically distinct from pyrite, which is iron sulfide with cubic crystal structure. Both structures do have in common that they contain the disulfide...

, hematite
Hematite
Hematite, also spelled as haematite, is the mineral form of iron oxide , one of several iron oxides. Hematite crystallizes in the rhombohedral system, and it has the same crystal structure as ilmenite and corundum...

, calcite
Calcite
Calcite is a carbonate mineral and the most stable polymorph of calcium carbonate . The other polymorphs are the minerals aragonite and vaterite. Aragonite will change to calcite at 380-470°C, and vaterite is even less stable.-Properties:...

, and organic matter.

Crooks Gap district

The Crooks Gap district of Fremont County contains uranium ore in fluvial sandstones of the Eocene
Eocene
The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...

 Battle Spring Formation.

Current Activity

By 2006, the only active uranium mine in Wyoming was the Smith Ranch-Highland
Smith Ranch-Highland
Smith Ranch and Highland are uranium mining operations located in Wyoming, 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 uranium production facility in the United States.Smith Ranch and...

 in-situ leaching operation in the Powder River Basin
Powder River Basin
The Powder River Basin is a geologic region in southeast Montana and northeast Wyoming, about east to west and north to south, known for its coal deposits. The region supplies about 40 percent of coal in the United States. It is both a topographic drainage and geologic structural basin...

, owned by Power Resources, Inc., a subsidiary of Cameco
Cameco
Cameco Corporation is the world's largest publicly traded uranium company, based in Saskatoon, Saskatchewan. In 2009, it was the world's second largest uranium producer, accounting for 16% of world production.-History:...

. The mine produced 907 tonnes of yellowcake
Yellowcake
Yellowcake is a kind of uranium concentrate powder obtained from leach solutions, in an intermediate step in the processing of uranium ores. Yellowcake concentrates are prepared by various extraction and refining methods, depending on the types of ores...

 (uranium oxide concentrate, U3O8) in 2006, making it the leading uranium producer in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

.

In October 2007, Energy Metals Corp. applied for a Nuclear Regulatory Commission
Nuclear Regulatory Commission
The Nuclear Regulatory Commission is an independent agency of the United States government that was established by the Energy Reorganization Act of 1974 from the United States Atomic Energy Commission, and was first opened January 19, 1975...

 (NRC) permit to start an in-situ leach
In-situ leach
In-situ leaching , also called in-situ recovery or solution mining, is a mining process used to recover minerals such as copper and uranium through boreholes drilled into a deposit, in situ....

 mine at the Moore Ranch deposit in Campbell County in the Powder River Basin
Powder River Basin
The Powder River Basin is a geologic region in southeast Montana and northeast Wyoming, about east to west and north to south, known for its coal deposits. The region supplies about 40 percent of coal in the United States. It is both a topographic drainage and geologic structural basin...

. Energy Metals is a subsidiary of Uranium One
Uranium One
Uranium One is a Canadian based uranium mining company with operations in Australia, Canada, Kazakhstan, South Africa and the United States.-History:...

. 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
Cameco Corporation is the world's largest publicly traded uranium company, based in Saskatoon, Saskatchewan. In 2009, it was the world's second largest uranium producer, accounting for 16% of world production.-History:...

) in Wyoming
Wyoming
Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...

 and Nebraska
Nebraska
Nebraska is a state on the Great Plains of the Midwestern United States. The state's capital is Lincoln and its largest city is Omaha, on the Missouri River....

 for recovery of the uranium.

Resistance to uranium mining

A campaign has been underway to halt any effort to mine uranium in the Black Hills because of its effect on Native American
Indigenous peoples of the Americas
The indigenous peoples of the Americas are the pre-Columbian inhabitants of North and South America, their descendants and other ethnic groups who are identified with those peoples. Indigenous peoples are known in Canada as Aboriginal peoples, and in the United States as Native Americans...

 and wildlife
Wildlife
Wildlife includes all non-domesticated plants, animals and other organisms. Domesticating wild plant and animal species for human benefit has occurred many times all over the planet, and has a major impact on the environment, both positive and negative....

 populations, as well as the effects of mining on the water table
Water table
The water table is the level at which the submarine pressure is far from atmospheric pressure. It may be conveniently visualized as the 'surface' of the subsurface materials that are saturated with groundwater in a given vicinity. However, saturated conditions may extend above the water table as...

 and local ranchers. Indigenous leaders and anti-nuclear
Anti-nuclear
The anti-nuclear movement is a social movement that opposes the use of nuclear technologies. Many direct action groups, environmental groups, and professional organisations have identified themselves with the movement at the local, national, and international level...

activists began organizing around this issue in the 1970s and there are still efforts underway to prevent mining on native lands.

External links


External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK