The Kennecott Copper Mine is an open-pit strip mine located 28 miles southwest of Salt Lake City. It is unique for being the world's largest excavation, measuring 2 and 3/4-miles across and 3/4-mile deep.
The mine is operated by Kennecott Utah Copper, which is the second-largest copper producer in the United States. The company's operations provide 13 percent of the copper needs of the country. Over 300,000 tons of refined copper are produced annually.
In addition to copper, the mine also produces about 400,000 ounces of gold, 4 million ounces of silver and 20 million pounds of molybdenum annually.
Kennecott Utah Copper began as Utah Copper on June 4, 1903. The company was created to mine and process low-grade copper ore found in a mountain in Bingham Canyon, located 25 miles southwest of Salt Lake City. Work on the mine began in 1906, and over the next century, the mountain would be reduced to the largest pit in the world.
Kennecott, another mining firm, would acquire Utah Copper in the 1930s. The Kennecott Mines Company was formed in Alaska in 1910 and began by mining a rich copper deposit in the Wrangell St. Elias Mountains. In 1915, Kennecott Mines became Kennecott Copper Corporation, which purchased a 25 percent interest in the Utah Copper Company. All of the assets of Utah Copper were finally acquired by 1936, and the company began to do business as a division of Kennecott.
The majority of mining companies today are owned by one of a very few companies. The story of Kennecott Copper is no different. In 1947 Utah Copper Company was dissolved and became the Utah Copper Division of Kennecott Copper Corporation.
In 1981, Standard Oil of Ohio acquired Kennecott, and in 1987 British Petroleum bought SOHIO. In 1989, RTZ Corporation purchased the company from British Petroleum; subsequently RTZ was renamed Rio Tinto. Today, Rio Tinto owns and operates the Kennecott Copper Mine.
Asbestos in Copper Mines
In most of the 1900s, whenever fire or excessive heat was a risk, various forms of asbestos were chosen as an insulator. Therefore, it was not uncommon for foundries such as the Kennecott Copper Mine to be built with materials made with asbestos. Another property of the fibrous mineral is that it's unaffected by conducting electricity. As a result, asbestos was utilized throughout the majority of copper plants, since processing copper not only involves extremely high temperatures but also uses large amounts of electric power. In addition, asbestos' ability to withstand caustic chemicals meant it was used in protective clothes, bench tops and lab equipment. There is little question that asbestos was excellent at protecting against extreme heat and flames. This strength, however, came with a significant cost in terms of human health.
Chrysotile was almost always the kind of asbestos used in these locations. Corporations for many years professed that chrysotile was the "good asbestos" and "environmentally friendly" - even in the face of scientific proof to the contrary. This chrysotile or serpentine asbestos was often mixed with amosite or crocidolite and formed into asbestos transite, which appeared for many years before being banned for construction purposes in the 1970s.
Asbestos transite could be laminated and sprayed onto ductwork and pipes just as cement could. Generally, new items made with transite were considered innocuous because the asbestos particles were trapped in the transite. Microscopic particles of asbestos are released into the atmosphere, however, as asbestos-containing transite grows older and becomes prone to crumbling. Asbestos when it is in this condition is called friable, a term used for materials that are easy to pulverize.
Why Friable Asbestos Is Bad
Asbestos particles, when friable, are easily dispersed into the environment. Medical conditions such as asbestosis and cancer can result from being exposed to airborne asbestos. Mesothelioma, a rare but almost always fatal disease of the mesothelium (the lining between the lungs and the pleural cavity), is strongly linked with exposure to asbestos. Swallowing asbestos fibers, which may occur when the tiny particles float in the air and land on food or drinks, can lead to pericardial or peritoneal mesothelioma.
Since medical research yielded more awareness of the risks of asbestos exposure, employees today enjoy the protection of stringent laws regulating the use of asbestos. However, when the Kennecott Copper Mine was constructed, asbestos was more common. And in way too many instances people worked with asbestos-containing materials without the protection of respirators or other protective gear.
Asbestos Exposure - a Hidden Danger
One of the insidious aspects of exposure to asbestos is the associated diseases can take ten, twenty, or even thirty years to manifest - frequently decades after a worker has left the employer. Given such a long time between asbestos exposure and the appearance of the resulting disease, a worker might not connect the current health problem with work he or she did decades ago. People that worked at or spent much time around sites such as the Kennecott Copper Mine should, therefore, inform their doctors about the possibility of asbestos exposure. Such information can enable physicians to make a timely diagnosis; especially with asbestos cancer, the sooner it is diagnosed, the better the odds of surviving or at the least of improved quality of life.Sources
Kennecott Utah Copper - Our History
University of Wisconsin - Asbestos Containing Material (ACM) - Laboratories and Shops
University of Wisconsin - Asbestos Disposal
Utah.com - Kennecott Utah Copper's Bingham Canyon Mine