Uranium mining in Arizona
Encyclopedia
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
.
as a byproduct of vanadium
mining. The district is in Apache County
, in the northeast corner of Arizona. The uranium
and vanadium
occur as carnotite
in sandstone of the Salt Wash member of the Morrison Formation
(Jurassic
). Production stopped in 1921. Another period of mining took place from 1941 to 1966, producing 360,000 pounds (160 metric tons) of uranium oxide (U3O8).
discovered uranium in 1942 in Monument Valley
on the Navajo Indian Reservation in northeast Arizona
. The first mine in the district opened in 1948. Uranium and uranium-vanadium minerals occur in fluvial channels of the Shinarump Sandstone member of the Triassic
Chinle Formation
. Ore deposits are associated with carbonized wood in the sandstone. Mining stopped in the Monument Valley
district in 1969, after producing 8.7 million pounds (3900 metric tons) of uranium oxide, more than has been produced from any other uranium mining district in Arizona. In 2005 the Navajo Nation
declared a moratorium on uranium mining on the reservation, for environmental and health reasons.
deposit in the Moenkopi Formation
was discovered to have economic concentrations of uranium
. The deposit was in the Lukachukai Mountains
of Apache County
. Uranium totaling 3.5 million pounds (1600 metric tons) of U3O8 was produced from 1950 until the mines closed in 1968.
prospector Hosteen Nez found uranium near Cameron
in Coconino County
in 1950. The uranium is in the Kayenta Formation
and the Chinle Formation
. Production was from 1950 to 1963, and totaled 1.2 million pounds (540 metric tons) of U3O8.
in 1950. The mine has been private property since 1906, and is today completely surrounded by Grand Canyon National Park
. The discovery led to the finding of uranium in other collapse breccia pipes
in northern Arizona. The breccia pipes were formed when overlying rocks collapsed into caverns formed in the Mississippian Redwall Limestone. The pipes are typically 300 feet (91.4 m) in diameter, and may extend up to 3000 feet (914.4 m) vertically.
Dripping Springs Quartzite in Gila County
. The uranium mineral is most commonly uraninite
, which occurs with pyrite
, marcasite
, and chalcopyrite
. The orebodies are in veins or strataform deposits within one-half mile of diabase
intrusions.
siltstones and mudstones of lacustrine
and paludal
origin of the Chapin Wash formation of the Date Creek Basin in Yavapai
, La Paz
, and Mohave
counties. The Anderson mine is now owned by Concentric Energy Corp. which is doing extensive development work to bring it into production.
recovered uranium as a byproduct from leach solutions recovering copper from waste material.
. Denison Mines
plans to begin mining its Arizona One mine in 2007. The deposit is in a breccia pipe
on the Colorado Plateau
of northern Arizona. In March of 2011, the State of Arizona issued air and water permits to Denison which would allow uranium mining to resume at three locations north of the Grand Canyon, subject to federal approval.
In July 2009 Secretary of the Interior Ken Salazar
announced a two-year ban on new mining on federal land in an area of approximately 1 million acres (4,046.9 km²) surrounding Grand Canyon National Park
. Although the ban is on all mining, the main effect is on exploration and development of breccia-pipe uranium deposits. Those claims on which commercial mineral deposits have already been discovered are exempt from the ban. During the two-year ban the Department of the Interior will study a proposed 20-year ban on new mining in the area.
Arizona
Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...
was a byproduct of vanadium
Vanadium
Vanadium is a chemical element with the symbol V and atomic number 23. It is a hard, silvery gray, ductile and malleable transition metal. The formation of an oxide layer stabilizes the metal against oxidation. The element is found only in chemically combined form in nature...
mining of the mineral 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:...
.
Carrizo Mountains
Uranium mining started in 1918 in the Carrizo MountainsCarrizo Mountains
The Carrizo Mountains are a small range 15 to 20 km in diameter located on the Colorado Plateau in northeastern Arizona. The range is about southwest of the Four Corners. The highest summit, Pastora Peak, is in elevation, whereas elevations on the surrounding plateau are near . The mountains...
as a byproduct of vanadium
Vanadium
Vanadium is a chemical element with the symbol V and atomic number 23. It is a hard, silvery gray, ductile and malleable transition metal. The formation of an oxide layer stabilizes the metal against oxidation. The element is found only in chemically combined form in nature...
mining. The district is in Apache County
Apache County, Arizona
-2010:Whereas according to the 2010 U.S. Census Bureau:*23.3% White*0.2% Black*72.9% Native American*0.3% Asian*0.0% Native Hawaiian or Pacific Islander*2.0% Two or more races*1.3% Other races*5.8% Hispanic or Latino -2000:...
, in the northeast corner of Arizona. The 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...
and vanadium
Vanadium
Vanadium is a chemical element with the symbol V and atomic number 23. It is a hard, silvery gray, ductile and malleable transition metal. The formation of an oxide layer stabilizes the metal against oxidation. The element is found only in chemically combined form in nature...
occur 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:...
in sandstone of the Salt Wash member of the Morrison Formation
Morrison Formation
The Morrison Formation is a distinctive sequence of Late Jurassic sedimentary rock that is found in the western United States, which has been the most fertile source of dinosaur fossils in North America. It is composed of mudstone, sandstone, siltstone and limestone and is light grey, greenish...
(Jurassic
Jurassic
The Jurassic is a geologic period and system that extends from about Mya to Mya, that is, from the end of the Triassic to the beginning of the Cretaceous. The Jurassic constitutes the middle period of the Mesozoic era, also known as the age of reptiles. The start of the period is marked by...
). Production stopped in 1921. Another period of mining took place from 1941 to 1966, producing 360,000 pounds (160 metric tons) of uranium oxide (U3O8).
Monument Valley
A NavajoNavajo people
The Navajo of the Southwestern United States are the largest single federally recognized tribe of the United States of America. The Navajo Nation has 300,048 enrolled tribal members. The Navajo Nation constitutes an independent governmental body which manages the Navajo Indian reservation in the...
discovered uranium in 1942 in Monument Valley
Monument Valley
Monument Valley is a region of the Colorado Plateau characterized by a cluster of vast sandstone buttes, the largest reaching above the valley floor. It is located on the northern border of Arizona with southern Utah , near the Four Corners area...
on the Navajo Indian Reservation in northeast Arizona
Arizona
Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...
. The first mine in the district opened in 1948. Uranium and uranium-vanadium minerals occur in fluvial channels of the Shinarump Sandstone member of the Triassic
Triassic
The Triassic is a geologic period and system that extends from about 250 to 200 Mya . As the first period of the Mesozoic Era, the Triassic follows the Permian and is followed by the Jurassic. Both the start and end of the Triassic are marked by major extinction events...
Chinle Formation
Chinle Formation
The Chinle is a geologic formation that is spread across the U.S. states of northern Arizona, Nevada, Utah, western New Mexico, and western Colorado. The Chinle is controversially considered to be synonymous to the Dockum Group in eastern Colorado, eastern New Mexico, southwestern Kansas, the...
. Ore deposits are associated with carbonized wood in the sandstone. Mining stopped in the Monument Valley
Monument Valley
Monument Valley is a region of the Colorado Plateau characterized by a cluster of vast sandstone buttes, the largest reaching above the valley floor. It is located on the northern border of Arizona with southern Utah , near the Four Corners area...
district in 1969, after producing 8.7 million pounds (3900 metric tons) of uranium oxide, more than has been produced from any other uranium mining district in Arizona. In 2005 the Navajo Nation
Navajo Nation
The Navajo Nation is a semi-autonomous Native American-governed territory covering , occupying all of northeastern Arizona, the southeastern portion of Utah, and northwestern New Mexico...
declared a moratorium on uranium mining on the reservation, for environmental and health reasons.
Lukachukai Mountains
In 1948, a copperCopper
Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...
deposit in the Moenkopi Formation
Moenkopi Formation
The Moenkopi is a geological formation that is spread across the U.S. states of New Mexico, northern Arizona, Nevada, southeastern California, eastern Utah and western Colorado. This unit is considered to be a group in Arizona. Part of the Colorado Plateau and Basin and Range, this formation was...
was discovered to have economic concentrations of 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...
. The deposit was in the Lukachukai Mountains
Lukachukai Mountains
The Lukachukai Mountains are a mountain range in northeast Arizona, entirely within the Navajo Indian Reservation. The highest point of the range is an unnamed point at 9466 feet above sea level...
of Apache County
Apache County, Arizona
-2010:Whereas according to the 2010 U.S. Census Bureau:*23.3% White*0.2% Black*72.9% Native American*0.3% Asian*0.0% Native Hawaiian or Pacific Islander*2.0% Two or more races*1.3% Other races*5.8% Hispanic or Latino -2000:...
. Uranium totaling 3.5 million pounds (1600 metric tons) of U3O8 was produced from 1950 until the mines closed in 1968.
Cameron district
NavajoNavajo Nation
The Navajo Nation is a semi-autonomous Native American-governed territory covering , occupying all of northeastern Arizona, the southeastern portion of Utah, and northwestern New Mexico...
prospector Hosteen Nez found uranium near Cameron
Cameron, Arizona
Cameron is a census-designated place in Coconino County, Arizona, United States. The population was 978 at the 2000 census. Most of the town's economy is tourist food and craft stalls, restaurants, and other services for north-south traffic from Flagstaff and Page...
in Coconino County
Coconino County, Arizona
-2010:Whereas according to the 2010 U.S. Census Bureau:*61.7% White*1.2% Black*27.3% Native American*1.4% Asian*0.1% Native Hawaiian or Pacific Islander*3.1% Two or more races*5.2% Other races*13.5% Hispanic or Latino -2000:...
in 1950. The uranium is in the Kayenta Formation
Kayenta Formation
The Kayenta Formation is a geologic layer in the Glen Canyon Group that is spread across the Colorado Plateau province of the United States, including northern Arizona, northwest Colorado, Nevada, and Utah. This rock formation is particularly prominent in southeastern Utah, where it is seen in the...
and the Chinle Formation
Chinle Formation
The Chinle is a geologic formation that is spread across the U.S. states of northern Arizona, Nevada, Utah, western New Mexico, and western Colorado. The Chinle is controversially considered to be synonymous to the Dockum Group in eastern Colorado, eastern New Mexico, southwestern Kansas, the...
. Production was from 1950 to 1963, and totaled 1.2 million pounds (540 metric tons) of U3O8.
Collapse breccia pipes
Uranium was discovered in the Orphan copper mine near the south rim of the Grand CanyonGrand Canyon
The Grand Canyon is a steep-sided canyon carved by the Colorado River in the United States in the state of Arizona. It is largely contained within the Grand Canyon National Park, the 15th national park in the United States...
in 1950. The mine has been private property since 1906, and is today completely surrounded by Grand Canyon National Park
Grand Canyon National Park
Grand Canyon National Park is the United States' 15th oldest national park and is located in Arizona. Within the park lies the Grand Canyon, a gorge of the Colorado River, considered to be one of the Wonders of the World. The park covers of unincorporated area in Coconino and Mohave counties.Most...
. The discovery led to the finding of uranium in other collapse breccia pipes
Arizona breccia pipe uranium mineralization
During the late 1970s and through the 1980s, Mohave and Coconino County, Arizona, immediately north and south of the Grand Canyon and west of the Navajo Indian Reservation were explored for Arizona breccia pipe uranium mineralization...
in northern Arizona. The breccia pipes were formed when overlying rocks collapsed into caverns formed in the Mississippian Redwall Limestone. The pipes are typically 300 feet (91.4 m) in diameter, and may extend up to 3000 feet (914.4 m) vertically.
Sierra Ancha district
Uranium mining started in 1953 from deposits in the PrecambrianPrecambrian
The Precambrian is the name which describes the large span of time in Earth's history before the current Phanerozoic Eon, and is a Supereon divided into several eons of the geologic time scale...
Dripping Springs Quartzite in Gila County
Gila County, Arizona
-2010:Whereas according to the 2010 U.S. Census Bureau:*76.8% White*0.4% Black*14.8% Native American*0.5% Asian*0.1% Native Hawaiian or Pacific Islander*2.0% Two or more races*5.4% Other races*17.9% Hispanic or Latino -2000:...
. The uranium mineral is most commonly 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...
, which occurs 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...
, and chalcopyrite
Chalcopyrite
Chalcopyrite is a copper iron sulfide mineral that crystallizes in the tetragonal system. It has the chemical composition CuFeS2. It has a brassy to golden yellow color and a hardness of 3.5 to 4 on the Mohs scale. Its streak is diagnostic as green tinged black.On exposure to air, chalcopyrite...
. The orebodies are in veins or strataform deposits within one-half mile of diabase
Diabase
Diabase or dolerite is a mafic, holocrystalline, subvolcanic rock equivalent to volcanic basalt or plutonic gabbro. In North American usage, the term diabase refers to the fresh rock, whilst elsewhere the term dolerite is used for the fresh rock and diabase refers to altered material...
intrusions.
Date Creek Basin
The Anderson uranium deposit was discovered in 1955 by an airborne gamma-radiation survey. Small amounts of ore were produced from 1955 to 1959. Uranium is associated with organic material in carbonaceous MioceneMiocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
siltstones and mudstones of lacustrine
Lake
A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. Lakes can be contrasted with rivers or streams,...
and paludal
Paludal
Paludal is derived from the Latin word palus .*Paludal, in geology, refers to sediments that accumulated in a marsh environment.*Paludal, in ecology, refers to the environment of a marsh.----...
origin of the Chapin Wash formation of the Date Creek Basin in Yavapai
Yavapai County, Arizona
-2010:Whereas according to the 2010 U.S. Census Bureau:*89.3% White*0.6% Black*1.7% Native American*0.8% Asian*0.1% Native Hawaiian or Pacific Islander*2.5% Two or more races*5.0% Other races*13.6% Hispanic or Latino -2000:...
, La Paz
La Paz County, Arizona
La Paz County is a county in the western part of the U.S. state of Arizona. As of the 2010 census its population was 20,489. The county seat is Parker...
, and Mohave
Mohave County, Arizona
Mohave County is located in the northwestern corner of the U.S. state of Arizona. As of the 2010 census, its population was 200,186, an increase of 45,154 people since the 2000 census count of 155,032. The county seat is Kingman...
counties. The Anderson mine is now owned by Concentric Energy Corp. which is doing extensive development work to bring it into production.
Porphyry copper byproduct
For some years starting in 1980, the Twin Buttes copper mine in Pima CountyPima County, Arizona
-2010:Whereas according to the 2010 U.S. Census Bureau:*74.3% White*3.5% Black*3.3% Native American*2.6% Asian*0.2% Native Hawaiian or Pacific Islander*3.7% Two or more races*12.4% Other races*34.6% Hispanic or Latino -2000:...
recovered uranium as a byproduct from leach solutions recovering copper from waste material.
Uranium Mining and the Native People
Uranium mining caused many Native Americans and animals to become sick. Some problems were that there was limited amount of water located on the reservation, so locals would have to travel long distances for water. The Mines would leave contaminated waters unattended and would not even put up fences to prevent anyone passing through. So the native would bring their livestock and gather water at the contaminated area. This caused mutation between the animals and the Native People.Current activity
There are currently no producing uranium mines in ArizonaArizona
Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...
. Denison Mines
Denison Mines
Denison Mines Corp. is a Canadian uranium exploration, development, and production company. Founded by Stephen B. Roman, and best known for its uranium mining in Elliot Lake, it later diversified into coal, potash, and other projects....
plans to begin mining its Arizona One mine in 2007. The deposit is in a breccia pipe
Arizona breccia pipe uranium mineralization
During the late 1970s and through the 1980s, Mohave and Coconino County, Arizona, immediately north and south of the Grand Canyon and west of the Navajo Indian Reservation were explored for Arizona breccia pipe uranium mineralization...
on the Colorado Plateau
Colorado Plateau
The Colorado Plateau, also called the Colorado Plateau Province, is a physiographic region of the Intermontane Plateaus, roughly centered on the Four Corners region of the southwestern United States. The province covers an area of 337,000 km2 within western Colorado, northwestern New Mexico,...
of northern Arizona. In March of 2011, the State of Arizona issued air and water permits to Denison which would allow uranium mining to resume at three locations north of the Grand Canyon, subject to federal approval.
In July 2009 Secretary of the Interior Ken Salazar
Ken Salazar
Kenneth Lee "Ken" Salazar is the current United States Secretary of the Interior, in the administration of President Barack Obama. A member of the Democratic Party, he previously served as a United States Senator from Colorado from 2005 to 2009. He and Mel Martinez were the first Hispanic U.S...
announced a two-year ban on new mining on federal land in an area of approximately 1 million acres (4,046.9 km²) surrounding Grand Canyon National Park
Grand Canyon National Park
Grand Canyon National Park is the United States' 15th oldest national park and is located in Arizona. Within the park lies the Grand Canyon, a gorge of the Colorado River, considered to be one of the Wonders of the World. The park covers of unincorporated area in Coconino and Mohave counties.Most...
. Although the ban is on all mining, the main effect is on exploration and development of breccia-pipe uranium deposits. Those claims on which commercial mineral deposits have already been discovered are exempt from the ban. During the two-year ban the Department of the Interior will study a proposed 20-year ban on new mining in the area.
See also
- Arizona breccia pipe uranium mineralizationArizona breccia pipe uranium mineralizationDuring the late 1970s and through the 1980s, Mohave and Coconino County, Arizona, immediately north and south of the Grand Canyon and west of the Navajo Indian Reservation were explored for Arizona breccia pipe uranium mineralization...
- Uranium mining in the United StatesUranium mining in the United StatesUranium mining in the United States is the extraction of uranium-bearing ore from the earth. 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...
- The Navajo People and Uranium MiningThe Navajo People and Uranium MiningThe Navajo People and Uranium Mining is a non-fiction book edited by Doug Brugge, Timothy Benally, and Esther Yazzie-Lewis; it uses oral histories to tell the stories of Navajo Nation miners and families in the uranium mining industry. The foreword is written by Stewart L. Udall, former U.S. House...