To Move A Mountain
Kennecott Utah Copper Parent Companies
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This page last updated on December 19, 2019.
Kennecott Copper Corporation
April 29, 1915
Kennecott Copper Corporation was incorporated in New York on April 29, 1915, to acquire all of the properties and assets of Kennecott Mines Company, which physical property lay at the Kennecott mine three miles from Kennecott, Alaska, and the Beatson mine on Latouche Island, Prince William Sound, Alaska. (Moody's Manual Of Railroads And Corporation Securities, Twenty-Third Annual Number, Industrial Section, Volume II, K to Z, 1922, page 1322) (Moody's Analysis Of Investments for 1917, page 1337, gives the date as May 4, 1915)
November 18, 1915
Guggenheim Exploration Company sold its 404,504 shares of Utah Copper Company to Kennecott Copper Corporation, payment being made in Kennecott stock on the basis of 1-1/4 shares of Kennecott for each share of Utah Copper. Guggenheim Exploration was to be dissolved in the near future, and this is how Kennecott, owned and controlled by the Guggenheim interests, started its majority interest and ownership in Utah Copper. (New York Times, November 18, 1915)
December 4, 1915
Kennecott Copper Corporation acquired 404,504 shares (24.9 percent) of Utah Copper Company, by purchase from Guggenheim Exploration Company. On December 31, 1916, Kennecott owned 435,404 shares of Utah Copper's 1,624,490 outstanding stock (26.7 percent). (Moody's Analysis Of Investments, Part II, Public Utilities and Industrials, 1917, page 1337)
March 16, 1916
Guggenheim Exploration was dissolved and its remaining interests merged with M. Guggenheim Sons. The new merged company become Guggenheim Brothers. (The Guggenheims: An American Epic, John H. Davis, 1989, page 120)
March 22, 1917
Kennecott purchased 200,000 shares of Utah Copper Company on the open market "in the last few months," at a reported cost of $20 million. This was in addition to the 404,504 shares acquired from Guggenheim Exploration prior to that company being dissolved. The total of 600,000 shares owned by Kennecott was not an actual majority, but gives practical control. (New York Times, March 22, 1917)
The Moody's Manual for 1922 reported that on December 31, 1921, in addition to the properties in Alaska, and the Copper River & Northwestern Railway, Kennecott Copper also owned 38 percent of Utah Copper Company. Of that 38 percent, Kennecott had purchased an initial 25 percent of Utah Copper from Guggenheim Exploration in return for a similar value of stock in Kennecott Copper Corporation. The additional 13 percent of Utah Copper was purchased between 1915 and the end of 1921. (Moody's Manual Of Railroads And Corporation Securities, Twenty-Third Annual Number, Industrial Section, Volume II, K to Z, 1922, page 1324)
February 3, 1933
Kennecott Copper Corporation owned 98-1/2 percent of Utah Copper Company. After the distribution of Nevada Consolidated Copper to Utah Copper stockholders (in other words, Kennecott) on or before February 14, 1933, Kennecott would own and control 87 percent of Nevada Consolidated Copper Company, which in-turn owned Ray Consolidated and Chino Copper. One year before, at the end of 1931, Utah Copper held 31 percent of Nevada Consolidated. (New York Times, February 5, 1933)
November 9, 1936
The stockholders of Utah Copper Company approved the merger of the company with "Copper Corporation of Utah." Shares of Utah Copper Company would be traded on the basis of one share of the old company for three shares of the new company. Ninety-nine percent of Utah Copper Company was owned by Kennecott Copper Corporation. (New York Times, November 10, 1936, "yesterday") (The article also references a "Utah Copper Corporation")
November 10, 1936
Kennecott Copper Corporation took full ownership of Utah Copper Company, having organized a new Utah Copper Company in Delaware, as a subsidiary, on November 6, 1936 for the purpose. The original Utah Copper Company had been organized in New Jersey in 1904. On April 29, 1915, Kennecott Copper Corporation had been organized in New York to acquire the worldwide Guggenheim copper interests, including all of the interests of Kennecott Mines Company in Alaska (including its Copper River & Northwestern Railroad) and 25 percent interest in Utah Copper Company in Utah, along with 96 percent interest in Braden Copper Company in Chile. In 1923 Kennecott Copper Corporation acquired 77 percent control of Utah Copper Company and by 1925 Kennecott had acquired 95 percent interest in Utah Copper. (Arrington and Hansen, The Richest Hole on Earth, A History of the Bingham Copper Mine, Utah State University, Volume XI, Number 1, October 1963. p. 68, citing Kennecott's 1936 Annual Report)
Kennecott chairman Stephen Birch, remarked that 17-cent copper was too high and uneconomic, adding that 12.5-cent copper is better for both the producers of copper, and the users of copper. (New York Times, May 5, 1937)
The original Kennicott copper mine in Alaska was closed. The profits from this mine in Alaska between 1911 and 1938 were reported as the reason the Kennecott Copper Corporation took full ownership of the Utah Copper Company, making it the Utah Copper Division of Kennecott Copper Corporation. (Deseret News, June 8, 1998)
Utah Copper Company was dissolved. The company was organized in 1936 to take over Kennecott Copper Corporation's operations in Utah. (New York Times, March 7, 1947)
January 1, 1947
Utah Copper Company became the Utah Copper Division of Kennecott Copper Corporation. (Kennecott Historical Index)
"Commencing January 1, 1947, Utah Copper operations are to be conducted under the name Kennecott Copper Corporation, Utah Copper Division. This is a change in name only. There will be no change in operating personnel, and the change will simplify accounting." ("Important Events In the History of the Bingham Mining District" document kept by Kennecott Engineering Department staff, citing "Mills Annual Report 1947, page 12")
June 29, 1968
Kennecott Copper Corporation purchased Peabody Coal Company. In 1963, Kennecott had purchased the Knight Ideal Coal Company in Utah. This small property was purchased so as to gain coal reserves which would provide a hedge against rising natural gas costs, both which serve as fuel for Kennecott's Central Power Station at Magna, Utah. Kennecott's experience managing this coal company and an involvement with the coal industry would later be the basis for Kennecott's purchase of Peabody. (Kennecott Copper Corporation Vs. Federal Trade Commission, Docket 71-1371, United States Court of Appeals, Tenth Circuit, September 15, 1972; F.T.C. 467 F.2d 67, 1972)
June 7, 1977
Kennecott Copper Corporation's sale of Peabody Coal Company was made final on June 7, 1977. The initial announcement of Kennecott's purchase of Peabody was made in July 1966, and the final purchase completed in March 1968. The sale was opposed by the Federal Trade Commission, which in May 1974 issued a order for Kennecott Copper to divest Peabody Coal. The forced sale was completed on June 7, 1977. (part from New York Times, June 8, 1977)
Name Change to Kennecott Corporation
May 6, 1980
Kennecott Copper Corporation changed its name to Kennecott Corporation at its 65th annual stockholder's meeting. (Deseret News, May 7, 1980; Salt Lake Tribune, May 7, 1980)
At the same time, Kennecott reorganized its major business units. The mining operations and mineral interests were organized as Kennecott Minerals Company. A second unit was called Kennecott Engineered Systems Company, and a third unit was called Kennecott Development Company, which was sold to Kennecott's subsidiary Carborundum Company in September 1980. (part from New York Times, May 16, 1980 and September 10, 1980)
(The earliest reference to Kennecott Minerals Company in agreements and contracts was in July 1979.)
January 28, 1981
After a three-year battle in corporate boardrooms and federal district courtrooms, a hostile takeover of Kennecott Copper Corporation by Curtiss-Wright Corporation failed. On January 28, 1981 both companies jointly announced that neither would attempt to take over the other for the next 10 years. (New York Times, January 29, 1981)
Sohio and British Petroleum
Kennecott was in a weakened financial state, and needed cash to modernize its operations. Its management had been distracted after the 1977 forced sale of Peabody Coal, and using the proceeds of that sale in 1978 to buy Carborundum Corporation, rather than using the money to start a modernization program for its copper mines. The facilities at the Bingham canyon mine needed to be upgraded to take advantage of a recently discovered high-grade body known as the North Ore Shoot Extension. Kennecott had been seeking to develop this new ore body through a joint venture with Fluor Corporation. "Kennecott has suffered from the neglect of its facilities. Over the last decade and a half [since 1966], management energy and cash flow was devoted to acquisition battles and to the protection of Peabody Coal, which they had to give up." The sale to Sohio gave Kennecott the cash to modernize. For Sohio, the Kennecott purchase gave the oil company a natural resource with a longer life span, and an outlet for the large amount of cash generated by its Prudhoe Bay reserves in Alaska. As of December 31, 1980, Sohio had cash reserves and marketable securities totaling $3.82 billion. (New York Times, March 14, 1981)
Standard Oil Company (Ohio), which was 53 percent owned by the British Petroleum Company, reached a definitive agreement to acquire all of Kennecott Corporation's approximately 28.5 million outstanding shares for $62 cash per share. The transaction was subject to approval of Kennecott shareholders and certain other conditions. (New York Times, May 5, 1981)
The New York Times of March 13, 1981 reported that the first contact came on February 27th, with Sohio's chairman contacting Kennecott's chairman about the possibility of a friendly deal. First indication of the sale came on Wednesday March 12, when the New York Stock Exchange halted trading of both companies. At the time, Sohio was the 14th largest American oil company. Sohio was headquartered in Cleveland, Ohio, and Kennecott was headquartered in Stamford, Connecticut. (New York Times, March 13, 1981)
The Kennecott Corporation, the nation's largest producer of copper, said that net income in the first quarter of 1981 plunged 43.7 percent, to $34.6 million, from $61.5 million, in the first quarter of 1980. Sales fell 15.1 percent, to $547.9 million, from $645.2 million. If not for the sale of one-third interest in its Chino operations to Mitsubishi Corporation, for a reported $42.1 million, Kennecott would have had a loss of $7.5 million. (New York Times, May 5, 1981)
June 2, 1981
Federal Trade Commission approved the merger of Sohio and Kennecott on June 2, 1981. The four-person commission voted 3-to-1 to reject a staff recommendation to sue Sohio on anti-trust grounds, due to concerns that the sale would result in a Sohio monopoly in the production of molybdenum. An agreement was signed between BP, which held 53 percent of Sohio, and the FTC for BP to sell, within 30 months, its 6.8 percent ownership of Amax, Kennecott's competitor in the production and sale of molybdenum. (New York Times, June 3, 1981, "yesterday"; Salt Lake Tribune, June 3, 1981)
June 4, 1981
Standard Oil Company of Ohio (Sohio) bought Kennecott Corporation and its Kennecott Minerals Company (KMC) subsidiary; 53 percent of Sohio was owned by British Petroleum (BP), which was 25 percent owned by the British government and 20 percent owned by Bank of England. (Salt Lake Tribune, September 24, 1981)
- $1.77 billion takeover of Kennecott by Sohio. (Salt Lake Tribune, March 27, 1981)
- Sohio made announcement of takeover on Thursday March 12, 1981. (New York Times, March 13, 1981, "yesterday"; Salt Lake Tribune, March 15, 1981)
- Sohio's bid of $62 per share was 2.5 times the current Kennecott share price of $27. (New York Times, March 13, 1981; Salt Lake Tribune, September 20, 1981)
- Notice of proposed merger of Sohio and Kennecott was filed with the Anti-Trust Division of the U.S. Justice Department on March 18, 1981. (Salt Lake Tribune, March 26, 1981)
- Sohio traded 25 percent of itself for BP's Alaska North Slope holdings in 1969. By 1980 BP had purchased 53 percent interest in Sohio. (Salt Lake Tribune, March 17, 1981)
- Sohio was largest producer of crude oil in United States, at 9 percent of all U.S. production - more than half of the Alaska North Slope. Kennecott shareholders voted to accept the merger on May 5, 1981. (Salt Lake Tribune, May 2, 1981)
- Kennecott shareholders approved the sale. Sale and merger not final until reviewed by Federal Trade Commission. (Salt Lake Tribune, May 6, 1981)
- Sohio formally acquired Kennecott on June 4, 1981, after approval by Kennecott shareholders and Federal Trade Commission. (Salt Lake Tribune, July 31, 1981)
January 1, 1982
Kennecott's Carborundum Corporation subsidiary, which consisted of six separate business units, was reorganized as Sohio Industrial Products. The new company also included the former Kennecott subsidiaries Chase Brass, Dorr-Oliver, and Panghorn. (Sohio News, Volume 36, Number 2, March 1982, page 5)
February 8, 1982
In a reorganization of Sohio entire corporate structure, Kennecott Minerals Company became part of the new Sohio Metals Mining Group, with Joklik as its head, with responsibility for Sohio's interests in copper, gold, silver, molybdenum, lead and zinc. The other groups included the Sohio Oil and Gas Group, the Downstream Petroleum Group, the Chemical and Industrial Products Group. (Sohio News, Volume 36, Number 2, March 1982, page 1, 10)
"British Petroleum gets a new name -- 'The British Petroleum Company Limited' has a new name. From now on, it will be known as 'The British Petroleum Company p.l.c.' The initials 'p.l.c.' stand for public limited company. The British government requires the new nomenclature under a Companies Act." (Sohio News, Volume 36, Number 2, March 1982, page 4)
In an MSHA decision dated September 16, 1985, the company was referred to as "Kennecott Minerals Company, Utah Copper Division." (Federal Mine Safety & Health Review Commission)
In late June 1987, after buying the remaining 45 percent of Sohio that it did not own, giving it full ownership of Sohio, British Petroleum Company (BP) merged its other interests in North America with those of Sohio to form BP America.
September 24, 1987
BP America announced the formation of BP Minerals America, combining the assets of Sohio's Kennecott Corporation, headquartered in Salt Lake City, and with BP North America's Denver-based Amselco Minerals. (BP America news release, dated September 24, 1987, "today")
(In its fall 1987 issue, the BP employee's magazine "BP America Scene" reported that BP had purchased the remaining 45 percent in June 1987.)
Sale To RTZ
December 14, 1988
British Petroleum (BP) confirmed rumors that it was negotiating the sale of its mineral and mining interests (BP Minerals America) to RTZ Corporation. Prior to the recently completed $400 million modernization, Kennecott's Bingham mine was one of Kennecott's most expensive operations. The modernization made it one of the most competitive copper mining operations in the world, producing 240,000 tons of copper annually. (Salt Lake Tribune, December 24, 1988; New York Times, December 15, 1988, citing a Reuters story)
In mid December 1988, there had been reports that the sale of Kennecott by BP Minerals America to RTZ was "signed, sealed and delivered," and that the BP board of directors would likely approve the sale on either December 14 or 15. The Wall Street Journal of December 13 carried a news item that BP was seeking to sell Kennecott to RTZ. (Deseret News, December 14, 1988; December 15, 1988)
January 3, 1989
British Petroleum Company, Britain's largest company, announced that it had agreed to sell it mineral interests to the international mining group RTZ Corporation Plc for a reported $4.4 billion. BP's managing director, Patrick Gilliam, said that the sale would allow BP to move away from its international mining activities, and focus on its core business of oil and petroleum production. The Utah copper and gold mines were managed as part of BP Minerals America, with BP as its parent company, and included mines in Utah, Nevada, South Carolina, Alaska and Montana. Besides BP Minerals America, the sale included BP's mining activities in Canada, Brazil, Norway, Zimbabwe, South Africa, Australia, Indonesia and New Guinea. (Deseret News, January 3, 1989)
At the same time as the RTZ announcement, in a separate $3.56 billion deal, BP announced that it would buy back 790 million of its own shares from the Kuwait Investment Office, reducing the government of Kuwait's stake in the company from 21.6 per cent to 9.9 per cent. The sale of Kuwait interests had been ordered by the British government to address concerns of the government's Monopolies and Mergers Commission that the large percentage posed a threat to British interests. (Deseret News, January 3, 1989)
The sale of Kennecott by BP to RTZ would allow BP to buy back the 22 per cent interest in BP held by the government of Kuwait. The reported figure for both transactions was $4.3 billion. The government of Kuwait, through its Kuwait Investment Office, purchased over a period of a few months, 21.6 per cent of BP, which was a portion of the 31.5 per cent of BP that was sold by the British government in October 1987 as part of Margaret Thatcher's move to privatize companies in which the government held a financial interest (the sale raised $12 billion for the British government). Concerns were soon raised by BP management and British politicians about foreign ownership of a British company, and in October 1988, Kuwait was allowed three years to reduce its ownership of BP, a total of 1.3 billion shares. (New York Times, October 5, 1988; January 4, 1989)
British Petroleum went through a worldwide corporate image change, with new company names for most of the former Standard Oil of Ohio (Sohio) business units having their Sohio names replaced by a simi liar BP name.
May 25, 1989
RTZ Corporation of London announced that it had completed the terms of its purchase of the mineral assets of BP, for a reported $4.3 billion. (New York Times, May 25, 1989)
June 30, 1989
The sale of BP Minerals America to RTZ was expected to close on June 30, 1989, following the approval of the sale by RTZ, Corp., shareholders in London on June 16, 1989. (Deseret News, June 16, 1989)
The sale was for all of BP's mineral assets worldwide, including Australia, Europe, and South Africa, as well as the holdings in the United States.
July 5, 1989
The name of BP Minerals America was changed to Kennecott Corporation on or about July 5, 1989. (Deseret News, July 5, 1989; Salt Lake Tribune, July 6, 1989) (Kennecott Minerals Company was a business unit of BP Minerals America, and remained a business unit of Kennecott Corporation.)
The following comes from an earlier Rio Tinto company history web page, now no longer available:
RTZ Corporation had its roots in the Rio Tinto Company organized in 1873 to mine the ancient copper works at Rio Tinto, Spain. In 1962 the Rio Tinto Company merged with The Consolidated Zinc Corporation, which had been organized in 1905 to treat zinc bearing tailings at Broken Hill in New South Wales, Australia. Rio Tinto had previously disposed of two-thirds of its Spanish interests in 1954, and the remainder was also disposed, making the zinc interests in Australia the focus of the new Rio Tinto-Zinc Corporation's activities. Following the 1962 merger, RTZ developed a number of major projects in South Africa, Namibia, and Portugal. It also grew through acquisitions, including the Borax group in 1968.
Between 1968 and 1985 significant interests in cement, chemicals, oil and gas and manufactured products were also developed. A major review of corporate strategy between 1987 and 1988 led to a series of disposals and acquisitions which refocused the company on mining and related activities. Between 1988 and 1994 non mining businesses were sold as going concerns, and interests in mining acquired. These included the 1989 acquisition of the major part of British Petroleum's international minerals businesses [including Kennecott's Bingham Canyon copper mine], and the 1993 acquisition of the Nerco and Cordero coal mining businesses in the US [in Wyoming's Powder River Basin].
Kennecott Utah Copper Corporation (KUCC) became a unit of RTZ Corporation (England). (Wall Street Journal, March 12, 1992)
Four years after purchasing BP Minerals America, RTZ Corporation announced the division of Kennecott Corporation into three separate operations: Kennecott Utah Copper, Kennecott Minerals Company, and Kennecott Energy Company.
(According to the May 2, 2006 issue of The News-Record of Gillette, Wyoming, where the company had its headquarters, Kennecott Energy Company was changed to Rio Tinto Energy America on May 1, 2006.)
October 9, 1995
RTZ Corporation, Kennecott's parent company based in London, announced that it would merge with CRA Ltd., an Australian company based in Melbourne. RTZ already owned 49 per cent of CRA. The merged companies will have operations in North America, Australia, South America, Asia, Europe and South Africa, embracing a broad range of products, principally copper, aluminum, coal, iron ore and gold, as well as other minerals and commodities. (Deseret News, October 10, 1995)
The RTZ Corporation Plc (of Britain) and CRA Limited (of Australia) were unified under common management.
CRA Limited was originally known as Conzinc Riotinto of Australia. Prior to the 1995 merger with RTZ, CRA had grown through the development of several important mineral discoveries, including Hamersley (iron ore) in Australia, Bougainville (copper) in Papua New Guinea, Comalco (bauxite, alumna refining and aluminum smelting) in Australia and New Zealand, Argyle (diamonds) and Blair Athol and Tarong (coal) in Australia, and Kelian (gold) and Kaltim Prima (coal) in Indonesia.
In an news item about the retirement of Bob E. Cooper, who had served as CEO and president of Kennecott Corporation since 1993, it was shown that Kennecott Corporation had three subsidiary companies as part of its North American operations: Kennecott Utah Copper Corporation; Kennecott Minerals Company; and Kennecott Energy Company. (Salt Lake Tribune, February 7, 1997)
RTZ closed its offices in downtown Salt Lake City as part of its global restructuring to reorganize the company along product lines - copper, iron ore, gold, aluminum - rather than along geographical lines that saw the North American group (the former BP Minerals America) manage of copper and coal properties, and the Australia group also manage copper and coal properties. Kennecott Utah Copper Corporation would report directly to RTZ in London, instead of Kennecott Corporation (the former BP Minerals America) in Salt Lake City. All parties in the RTZ copper group, including its mines in Brazil and Chile in South America, would also report directly to RTZ in London. The coal group would report to offices in Melbourne in Australia. The change meant that the 75 employees of Kennecott Corporation would no longer have jobs. The change would have no effect on the operations of Kennecott Utah Copper, which had its offices in Magna. (Deseret News, March 19, 1997)
(Kennecott had occupied the top six floors of the 18-floor office building owned by Zion Securities on the southeast corner of Main Street and South Temple Street in Salt Lake City. When the building was completed in 1965, it used copper panels as part of its exterior design, and was officially known as the Kennecott Building. After Kennecott vacated the building in 1997, the copper panels were painted over and the building was renamed as the Zions Bank Building.)
June 2, 1997
RTZ Corporation changed its name to Rio Tinto. (Rio Tinto press release dated June 2, 1997)
RTZ Corporation PLC became Rio Tinto plc (of Britain), and CRA Limited became Rio Tinto Limited (of Australia).
(The term "plc" is an abbreviation of "public limited company," a type of publicly held, limited liability company in the United Kingdom, whose shares are freely sold and traded to the public. Directors must be British or European Union citizens)
Rio Tinto's Kennecott group of companies in North America include:
Kennecott Utah Copper (Bingham Copper Mine)
Kennecott Minerals Company (U.S. gold, silver, copper, and base metal operations)
Kennecott Exploration Company (North American exploration activities)
Kennecott Energy Company (U.S. coal operations) (changed to Rio Tinto Energy America on May 1, 2006)
Each company operates as a separate entity
KCC or KMC or KUC
The Kennecott Minerals Co. (KMC) name was in place from mid 1979 through mid 1989, and any locomotives delivered in that time period likely had the Kennecott Minerals Company name applied to them. Several were locally painted with KMC letters. The wide-cab MP15ACs (120-122) and the SD40-2s (101-107) were delivered in 1978 lettered as Kennecott Copper Corporation. The standard MP15ACs (701, 704) were delivered in late 1978, also with KCC lettering.
Railroad operations were severely cut back with the mine modernization of 1985-1986. Most of the ore haulage in the mine was replaced by a conveyor belt to the new mill at Copperton, and a slurry pipeline to the Garfield smelter. Railroad operations were only used as backup for when the slurry pipeline was out of service.
When the 900-series locomotives (the green units) were relettered in the mid 1980s, they received KMC letters, "KMC, Utah Copper Division." When 123, 910 and 911 were transferred in 1983-1984, they were repainted as green units, and lettered as just "Kennecott," not as KMC. Only the two red smelter units were delivered in 1981 lettered as Kennecott Minerals Company.
The last train of ore was loaded in the mine in March 2000, with the ore being moved by train to the North Complex (Bonneville crusher and Magna mill), supplementing the Copperton mill. The North Complex was shut down in 2001, and all railroad operations between the mine and the smelter ended in June 2001. In December 2001, Kennecott shut down its railroad operations in the vicinity of the refinery and smelter at Garfield, and the operations have been contracted out since that time.
Utah Copper Company was sold to Kennecott Copper Corporation in November 10, 1936. Kennecott had organized a new Utah Copper Company in Delaware, as a subsidiary, on November 6, 1936 for the purpose. The original Utah Copper Company had been organized in New Jersey in 1904.
Utah Copper Company became the Utah Copper Division of Kennecott Copper Corporation on January 1, 1947.
Kennecott Minerals Company (KMC) name was first used in mid 1979. In May 1980 Kennecott Copper Corporation changed its name to Kennecott Corporation, and the worldwide mining operations were formally placed under control of KMC.
In February 1982, a SOHIO news release stated that Kennecott Minerals Company became part of the new Sohio Metals Mining Group, with responsibility for Sohio's interests in copper, gold, silver, molybdenum, lead and zinc. The other groups included the Sohio Oil and Gas Group, the Downstream Petroleum Group, the Chemical and Industrial Products Group. Other references from 1985 show the Utah copper mine as Kennecott Minerals Company, Utah Copper Division.
The mine shut down in April 1985, and the mills and smelter were shut down in August 1985. The mine reopened in September 1986, and the mills restarted in December 1986. The new smelter at Garfield produced its first copper in July 1987. In late 1986, Kennecott sold its operations in New Mexico and Arizona. (Nevada had been shut down in September 1978.)
In September 1987 Sohio was changed to BP America, with KMC still as a subsidiary.
In July 1989, BP sold the Kennecott business to RTZ (later Rio Tinto), and March 1992 the Utah copper mine (and its railroad operations) became Kennecot Utah Copper, a subsidiary of RTZ of England. Although there was still a Kennecott Minerals Company, it did not include any of the metal mines, and specifically did not include the Utah railroad operations.
Kennecott Corporation History -- A 1999 history of Kennecott Corporation, lifted from International Directory of Company Histories. (identical text used by Answers.com)