Bioleaching is the extraction or liberation of metals from their ores through the use of living organisms. Bioleaching is one of several applications within biohydrometallurgy and several methods are used to treat ores or concentrates containing copper, zinc, lead, arsenic, antimony, nickel, molybdenum, gold, silver, and cobalt.
The Summitville mine was a gold mining site in the United States, located in Rio Grande County, Colorado 25 miles (40 km) south of Del Norte. It is remembered for the environmental damage caused in the 1980s by the leakage of mining by-products into local waterways and then the Alamosa River.
In mining, tailings or tails are the materials left over after the process of separating the valuable fraction from the uneconomic fraction (gangue) of an ore. Tailings are different from overburden, which is the waste rock or other material that overlies an ore or mineral body and is displaced during mining without being processed.
The Berkeley Pit is a former open pit copper mine in the western United States, located in Butte, Montana. It is one mile (1.6 km) long by one-half mile (800 m) wide, with an approximate depth of 1,780 feet (540 m). It is filled to a depth of about 900 feet (270 m) with water that is heavily acidic, about the acidity of Coca-Cola, lemon juice, or gastric acid. As a result, the pit is laden with heavy metals and dangerous chemicals that leach from the rock, including copper, arsenic, cadmium, zinc, and sulfuric acid.
Acid mine drainage, acid and metalliferous drainage (AMD), or acid rock drainage (ARD) is the outflow of acidic water from metal mines and coal mines.
Acidithiobacillus is a genus of the Acidithiobacillia in the phylum "Pseudomonadota". This genus includes ten species of acidophilic microorganisms capable of sulfur and/or iron oxidation: Acidithiobacillus albertensis, Acidithiobacillus caldus, Acidithiobacillus cuprithermicus, Acidithiobacillus ferrianus, Acidithiobacillus ferridurans, Acidithiobacillus ferriphilus, Acidithiobacillus ferrivorans, Acidithiobacillus ferrooxidans, Acidithiobacillus sulfuriphilus, and Acidithiobacillus thiooxidans.A. ferooxidans is the most widely studied of the genus, but A. caldus and A. thiooxidans are also significant in research. Like all "Pseudomonadota", Acidithiobacillus spp. are Gram-negative and non-spore forming. They also play a significant role in the generation of acid mine drainage; a major global environmental challenge within the mining industry. Some species of Acidithiobacillus are utilized in bioleaching and biomining. A portion of the genes that support the survival of these bacteria in acidic environments are presumed to have been obtained by horizontal gene transfer.
Ferroplasma is a genus of Archaea that belong to the family Ferroplasmaceae. Members of the Ferroplasma are typically acidophillic, pleomorphic, irregularly shaped cocci.
A lithoautotroph is an organism which derives energy from reactions of reduced compounds of mineral (inorganic) origin. Two types of lithoautotrophs are distinguished by their energy source; photolithoautotrophs derive their energy from light while chemolithoautotrophs (chemolithotrophs or chemoautotrophs) derive their energy from chemical reactions. Chemolithoautotrophs are exclusively microbes. Photolithoautotrophs include macroflora such as plants; these do not possess the ability to use mineral sources of reduced compounds for energy. Most chemolithoautotrophs belong to the domain Bacteria, while some belong to the domain Archaea. Lithoautotrophic bacteria can only use inorganic molecules as substrates in their energy-releasing reactions. The term "lithotroph" is from Greek lithos (λίθος) meaning "rock" and trōphos (τροφοσ) meaning "consumer"; literally, it may be read "eaters of rock". The "lithotroph" part of the name refers to the fact that these organisms use inorganic elements/compounds as their electron source, while the "autotroph" part of the name refers to their carbon source being CO2. Many lithoautotrophs are extremophiles, but this is not universally so, and some can be found to be the cause of acid mine drainage.
Biomining is the technique of extracting metals from ores and other solid materials typically using prokaryotes, fungi or plants. These organisms secrete different organic compounds that chelate metals from the environment and bring it back to the cell where they are typically used to coordinate electrons. It was discovered in the mid 1900s that microorganisms use metals in the cell. Some microbes can use stable metals such as iron, copper, zinc, and gold as well as unstable atoms such as uranium and thorium. Large chemostats of microbes can be grown to leach metals from their media. These vats of culture can then be transformed into many marketable metal compounds. Biomining is an environmentally friendly technique compared to typical mining. Mining releases many pollutants while the only chemicals released from biomining is any metabolites or gasses that the bacteria secrete. The same concept can be used for bioremediation models. Bacteria can be inoculated into environments contaminated with metals, oils, or other toxic compounds. The bacteria can clean the environment by absorbing these toxic compounds to create energy in the cell. Bacteria can mine for metals, clean oil spills, purify gold, and use radioactive elements for energy.
In the United States, copper mining has been a major industry since the rise of the northern Michigan copper district in the 1840s. In 2017, the US produced 1.27 million metric tonnes of copper, worth $8 billion, making it the world's fourth largest copper producer, after Chile, China, and Peru. Copper was produced from 23 mines in the US. Top copper producing states in 2014 were Arizona, Utah, New Mexico, Nevada, and Montana. Minor production also came from Idaho, and Missouri. As of 2014, the US had 45 million tonnes of known remaining reserves of copper, the fifth largest known copper reserves in the world, after Chile, Australia, Peru, and Mexico.
Tar Creek Superfund site is a United States Superfund site, declared in 1983, located in the cities of Picher, Douthat and Cardin, Ottawa County, in northeastern Oklahoma. From 1900 to the 1960s lead mining and zinc mining companies left behind huge open chat piles that were heavily contaminated by these metals, cadmium, and others. Metals from the mining waste leached into the soil, and seeped into groundwater, ponds, and lakes. Because of the contamination, Picher children have suffered elevated lead, zinc and manganese levels, resulting in learning disabilities and a variety of other health problems. The EPA declared Picher to be one of the most toxic areas in the United States.
The outflow of acidic liquids and other pollutants from mines is often catalysed by acid-loving microorganisms; these are the acidophiles in acid mine drainage.
Spring Creek Debris Dam is an earthfill dam on Spring Creek, a tributary of the Sacramento River, in Shasta County in the U.S. state of California. Completed in 1963, the dam, maintained by the U.S. Bureau of Reclamation, serves primarily to collect severe acid mine drainage stemming from the Iron Mountain Mine. The dam forms the Spring Creek Reservoir, less than 1 mile (1.6 km) long. Spring Creek and South Fork Spring Creek flow into the reservoir from a 16-square-mile (41 km2) watershed. The dam is directly upstream from the city of Keswick, California and the Keswick Reservoir. The operation is part of the Trinity River Division of the Central Valley Project.
Mining in the United States has been active since the beginning of colonial times, but became a major industry in the 19th century with a number of new mineral discoveries causing a series of mining rushes. In 2015, the value of coal, metals, and industrial minerals mined in the United States was US$109.6 billion. 158,000 workers were directly employed by the mining industry.
Leviathan Mine is a United States superfund site at an abandoned open-pit sulfur mine located in Alpine County, California. The mine is located on the eastern slope of the Sierra Nevada at about 7,000-foot (2,100 m) elevation, 6 miles (9.7 km) east of Markleeville and 24 miles (39 km) southeast of Lake Tahoe. The mine site comprises approximately 250 acres (100 ha) of land surrounded by the Toiyabe National Forest, which is only accessible a few months a year. The approximately 22 million tons of sulfur ore-containing crushed rock at the mine are responsible for contaminating the Leviathan and Aspen Creek, which join with Mountaineer Creek to form Bryant Creek which ultimately empties into the East Fork of the Carson River. These water bodies are listed as 303(d) impaired. The site location is seismically active.
Rimini, is a ghost town in Lewis and Clark County, Montana, United States. It is one of the oldest mining districts in the state. It was established when silver lodes were discovered in 1864. Other names for the district were Lewis and Clark, Tenmile, Vaughn, Colorado, and Bear Gulch. It was the site of Camp Rimini.
The New Idria Mercury Mine encompasses 8,000 acres of land in the Diablo Mountain range, incorporating the town of Idria in San Benito County, California. Idria, initially named New Idria, is situated at 36°25′01″N120°40′24″W and 2440 feet (680m) above mean sea level. The area was, in the past, recorded in the US Census Bureau as a rural community; however, Idria has become a ghost town since the closing of once lucrative mining operations in the early 1970s.
Abandoned mine drainage is a form of water pollution involving water that has been polluted by contact with mines, typically coal mines. Although it is sometimes called "acid mine drainage", not all abandoned mine drainage is acidic.
According to a survey completed by the Colorado Geological Survey between 1991 and 1999, the number of abandoned mines in Colorado is 18,382. The Arkansas Headwaters, Las Animas River, Rio Grande Headwaters, Alamosa, and Uncompahgre were the priority watersheds studied in this survey. In the survey, analysis was completed with Environmental Degradation Measures ranging from none to extreme. Results showed 26 abandoned mines with extreme degradation and mineral hazards, 219 with significant degradation, and 672 potentially significant hazards.
The Blue Ledge Mine is an inactive underground copper mine that has been classified as a Superfund Site by the Environmental Protection Agency (EPA) due to high concentrations of heavy metals. The mine is located approximately 3 miles south of the California–Oregon border in the Rogue River-Siskiyou National Forest. It is within the Siskiyou Mountain range, and sits near a summit at about 4,800 feet above sea level. The underground mining excavations span over 2 miles, and it is one of the largest mining operations to have existed in the region.
