Bingham Canyon Copper Mine

The Bingham Canyon Copper Mine is an open-pit copper mine southwest of Salt Lake City, Utah, in the Oquirrh Mountains, US; it is more commonly known as Kennecott Copper Mine among locals. The mine is that the largest man-made excavation, and deepest open-pit mine within the world, which is taken into account to own produced more copper than the other mine in history quite 19 million tons. The mine is owned by Rio Tinto Group, a British-Australian multinational corporation.

The classic copper porphyry orebody isn’t only significant but also experiences a reasonably uniform distribution of sulphide mineralization, mainly chalcopyrite. The existing pit was worked out by 2013, but the open-pit and then underground mining continued after that. As of end-2018, proven and probable open-pit reserves totaled 394Mt grading 0.45% copper, 0.022% molybdenum, 0.18g/t gold and 2.02g/t silver. Total mineral resources were 82Mt at 0.28% copper, 0.10g/t gold, 0.043% molybdenum and 1.54g/t silver.

The copper operations at Bingham Canyon Mine are managed through Kennecott Utah Copper Corporation which operates the mine, a concentrator plant, a smelter, and a refinery. The mine has been in production since 1906, and has resulted in the creation of a pit over 0.75 miles (1,210 m) deep, 2.5 miles (4 km) wide, and covering 1,900 acres (3.0 sq mi; 7.7 km2). It was designated a National Historic Landmark in 1966 under the name Bingham Canyon Open Pit Copper Mine.

Mining first began in Bingham Canyon within the late nineteenth century, when shafts were sunk to get rid of gold, silver, and lead deposits that played out by the first 1900s. it might take the appearance of open-pit mining in 1899 to show the Bingham copper deposit into an economically favorable resource. In open-pit mining, the copper-containing rocks are excavated from the surface downward in terraces. By the 1930s, open-pit mining had turned “the Hill” at Bingham Canyon into “the Pit.”

The end of the nineteenth century saw the consolidation of the small claims of many individual prospectors in Bingham Canyon into the hands of copper giants like the Boston Consolidated and Utah Copper Companies. The formation of these companies not only required a large supply of capital resources but also created a demand for cheap labor. The flood of immigrants that resulted made Bingham one of the most ethnically diverse areas in the state of Utah. It was estimated that in 1912, 65 percent of the residents were foreign-born.

The Bingham Canyon pit is now 2.5 miles wide and very deep. Mining uses a rotary drilling/blasting-shovel/truck in-pit crushing system, with two to four blasts a day. To contain costs, management has been quick to utilize the most cost-effective drilling, loading and haulage equipment, and management tools available.

At 9:30 pm on April 10, 2013, a landslide occurred at the mine. Around 2.3–2.5 billion cubic feet (65×106–70×106 m3) of dirt and rock thundered down the side of the pit. The massive slide was expected to cut the production of mined copper by 100,000 tonnes (110,000 short tons). A second slide caused an evacuation of 100 workers on September 11, 2013.

The variety of people in Bingham Canyon helped transform “the hill,” as the mining operations of the Utah Copper Company (later Kennecott Copper Corporation) were originally called, into the world’s largest open-pit copper mine. This expansion continually required the purchase of living areas for miners as the old towns of the canyon were gradually swallowed. Highland Boy and Copperfield were dismantled by 1960 and the last buildings in Bingham were torn down in 1972. Lark had disappeared from the map by the end of 1980. Copperton remains the sole survivor of the communities that helped to make Bingham Canyon one of the most culturally diverse and rich areas of Utah.

Today’s copper market is booming thanks to global demands from construction, telecommunications, and electronics sectors of the economy. The Kennecott Utah Copper Company removes about half a million tons of material from the Bingham Canyon Mine every day for processing. In 1906, the rate of removal was 100,000 tons of material per month. Over 17 million tons of copper have been removed to date. Geological and engineering models suggest that the mine can be deepened by an additional 200 meters before extraction costs become greater than the value of the remaining copper.

The Bingham Canyon Copper Mine is the largest artificially made excavation in the world and is visible to the naked eye from an orbiting space shuttle. Employing some 2,000 workers, 450,000 short tons (400,000 long tons; 410,000 t) of material are removed from the mine daily. Electric shovels can carry up to 56 cubic yards (43 m3) or 98 short tons (88 long tons; 89 t) of ore in a single scoop. Ore is loaded into a fleet of 64 large dump trucks which each carry 255 short tons (228 long tons; 231 t) of ore at a time; the trucks themselves cost about $3 million each. There is a five-mile (8 km) series of conveyors that take ore to the Copperton concentrator and flotation plant. The longest conveyor is 3 miles (4.8 km) long.

The current smelting facilities are the result of major investment, comprising a new primary flash smelter and flash converter system, designed by Outokumpu with input from Kennecott, plus a slag treatment plant. The converter treats matte that has been granulated and powdered. The 98.6% copper from the new converter is refined to 99.5% copper in two anode furnaces. Cast anodes are railed 3km to the refinery’s electrolytic tank house, where marketable high-purity copper is produced and the gold and silver content of the concentrate is also recovered.

The geological and chemical processes that produce copper deposits also produce minerals such as iron sulfides, which react with water or oxygen on the surface to produce colorful minerals. Geologists can sometimes use satellite observations to identify places where the topography and the rock types on the surface suggest copper ores might be present below ground. Bingham Canyon has proven to be one of the world’s most productive mines. The value of the resources extracted from the Bingham Canyon Mine is greater than the Comstock Lode, Klondike, and California gold rush mining regions combined. Mines in Chile, Indonesia, Arizona, and New Mexico now exceed Bingham Canyon’s annual production rate.

 

Information Sources:

  1. earthobservatory.nasa.gov
  2. mining-technology.com
  3. uen.org
  4. wikipedia