Anaconda In Utah
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This page was last updated on June 18, 2022.
Anaconda as a mining company, first came to Utah in March 1924 with its purchase of the Utah Consolidated Mining Company. The purchase (actually a foreclosure) was by Anaconda's International Smelting Company subsidiary, which it had controlled since 1914. The smelter had begun producing copper in August 1910, and lead in February 1912.
But the persons and interests who controlled Anaconda in those early years, namely the Rockefellers and their associates, also owned Standard Oil. This group was usuallly referred to variously in the newspapers as the Standard Oil trust, or the Standard Oil crowd.
The Highland Boy mine in Carr Fork in the Bingham district was owned and operated by Utah Consolidated Mining Company, which had its own smelter out in the Salt Lake Valley. The smelter smoke suit of 1904 forced them to close that smelter and find other smelting capabilities. The obvious choice was the newly completed Garfield smelter on the south shore of Great Salt Lake, but the two companies failed to come to agreeable terms for contracts that would bring all of Utah Consolidated's ores solely to the Garfield smelter. Instead, the principle persons and their investors (referred to as the Cole-Ryan interests), organized the International Smelting & Refining Company to build a new smelter in competition to the Garfield company to process ore coming from Utah Consolidated's mines, and custom ores from other mines in the region. The Tooele Valley Railway was built to serve the International smelter to bring in these custom ores from around the region, and was opened in 1910. A lead-silver smelter was added in 1912.
Ore arrived at the Tooele smelter by two methods, either by the 20,000 feet long aerial tramway of Utah Consolidated that traversed the ridge from Bingham Canyon, or by the Tooele Valley Railway that operated between International and a connection with Union Pacific at Tooele Junction (later Warner), west of Tooele.
Ore continued to arrive at the International smelter from the Utah Consolidated's mines in Bingham Canyon. Through a series of court cases and mergers, Utah Consolidated was reorganized as the Utah Delaware mining company, and in 1937 was combined with several other underground Bingham/Carr Fork mines, including Utah Apex to form the new company known as National Tunnel and Mines Company. In 1944, the company purchased Utah Metal and Tunnel.
From 1910 through 1972, the company operated copper and lead smelters and a lead-zinc flotation mill. The smelter processed ores mined from its own mines, and other mines in Utah and Nevada. The copper smelter was closed in 1946, followed by the closure of the lead/zinc flotation mill in 1968, and finally, closure of the lead smelter in 1972. The entire site was demolished during the years 1972-1974.
"In 1913 the company acquired the International Smelting and Refining Company, which owned smelters at Tooele, Utah, and Miami, Arizona, as well as the Raritan Copper Works in New Jersey. In 1922 Anaconda bought the American Brass Company in Waterbury, Connecticut, one of the major producers of finished copper products. Also in the early 1920s, Anaconda invested in Chile, acquiring the Chuquicamata copper mine from the Guggenheim family, as well as the smaller, but important, Potrerillos mine. It acquired from the heirs of Georg von Giesche a large zinc treatment plant at Katowice, Poland. In 1928 W.A. Clark's heirs sold his Montana companies to Anaconda. In 1955, in recognition of the wide range of corporate operations, the company name was changed to The Anaconda Company." "In 1971, however, Chile nationalized the Chuquicamata and other American-owned mines. This, along with low copper prices brought about a financial crisis. Forced to meet financial deadlines in New York, the company sold its entire lumber operation, including thousands of square miles of Montana timber land and the Bonner mill, to Champion International. This liquidation, however, did not solve the company's financial problems, and in 1979 the company was purchased by the Atlantic-Richfield Company (ARCO)." (Historical Note, Anaconda Copper Mining Company records, 1876-1974, Archives West)
In 1969, Anaconda began exploration drilling with plans for a large expansion project. In 1974, Anaconda constructed and operated a copper mine and mill known as the "Carr Fork Operations". The main mill of the new Carr Fork operation was one mile east of the International Smelting smelter property in Pine Canyon on approximately 12.5 acres. The Carr Fork operation began processing ore in 1979 and ran until ARCO shut it down in 1981 (Atlantic Richfield purchased Anaconda in 1977).
The Carr Fork mine stopped production in November 1981, while Anaconda waited for copper prices to rise. When this did not happen, the processing facilities were torn down, sold, and removed from the property in late 1984. The Carr Fork Operation property was sold to Kennecott Copper in October 1985. This included the mine and mill along with several acres of land east of the smelter site.
Tooele Valley Railway was used to haul away the scrap as the International smelter was torn down in 1972-1974, and remained to serve the new Carr Fork mine and mill in Pine Canyon. It was finally shut down and abandoned when the Pine Canyon "Carr Fork" mine and mill shut down, with its last day of operation being on August 28, 1982.
Anaconda bought, at auction, the properties of the bankrupt National Tunnel and Mines in 1948, for $500,000. They had held a large interest, at times a controlling interest, since the earliest days in 1914 when the International smelter had opened. But in 1948, they made it official and took full ownership of the Bingham mines, the Elton Tunnel, the International smelter, and the Tooele Valley railroad.
The prices on the metal markets had collapsed due to the end of wartime subsidies, and Anaconda had plenty of other active mines worldwide, and because the ore at Bingham had essentially been exhausted and worked out, they let the Bingham mines go idle. Exploration and research restarted in 1963, and exploritory drilling started in 1969. The International smelter closed in 1972, but Anaconda continued its exploration, looking for new ore bodies at Bingham.
In 1974, Anaconda announced a new $136 million project to produce copper from a new mine, from a new ore body found among its properties laying under its properties at the top of Carr Fork. Development began of new tunnels and shafts, and underground facilities, along with a new mill and above-ground facilities in Dry Canyon, on the Tooele side of the Oquirrh mountains. In 1979, production began. In the mean time, in 1977, Atlantic Richfield (Arco) used its new mega-profits from its oil fields in Alaska to buy Anaconda.
Arco was an oil company, and its top-level management was a bit mystified when it came to hard-rock copper mining. Their heart wasn't really in the effort, and although excellent progress was being made in developing the Carr Fork project, in 1982, Arco closed the project. Many people on the inside, and observers on the outside, felt that the Carr Fork project had great potential, and that shutting the project down was a big mistake, since it was reportedly the most modern and productive underground mine in the world. But history is filled with good projects being ignored by inept managers, as well as bad projects being promoted far past their time.
The Carr Fork Operation property was sold to Kennecott Copper in October 1985.
June 18, 1895
Anaconda Copper Mining Company was organized to own and control the largest copper mine in Montana, located at Butte. In 1899, a large percentage of ownership, and control passed to Amalgamated Copper Company. At the time, Anaconda was the largest producer of copper in the world. (The Copper Handbook, Volume II, 1901, page 294)
April 27, 1899
Amalgamated Copper Company was organized as a holding company, owning either outright, or having controlling interest in the copper mines of Butte, Montana. The company was owned by the Rockefeller interests (Henry H. Rogers and William G. Rockefeller). (The Copper Handbook, Volume II, 1901, page 292)
The original president of the Amalgamated copper trust was Marcus Daly, and the trust was formed to buy control of the Anaconda company. (Salt Lake Herald, May 14, 1899, includes a full page summary of the players in the worldwide copper market, and the need for stabilization of copper prices.)
The International Smelting & Refining Company was rolled into the organization of a larger International Smelting Company, organized in 1914 by Anaconda Copper Company to control and operate several of its metal smelting and refining properties.
The International Smelting Company was organized in May 1914 as a subsidiary of Anaconda Copper Company to take over and hold its interest in the former International Smelting & Refining Company, and other properties in Arizona and Utah, along with a copper refinery in New Jersey and a lead refinery in East Chicago.
The sale of International to Anaconda was in the form of an exchange of stock: 1 share of International stock was exchanged for 3.3 shares of Anaconda stock. The then-current market value of the exchange was reported as being $110 million. The International company was known as a Ryan corporation, with John D. Ryan as its president. "The same interests that control the Amalgamated and Anaconda company control this company." (The Anaconda Standard, April 22, 1914)
February 18, 1924
International Smelting foreclosed on Utah Consolidated Mining Co. for the $1.3 million mortgage it held, from a note that was issued on January 27, 1922 (when the district court initially decided on the damages). The foreclosure was filed in the U. S. District court. The mortgage was written to include all parcels and property as collateral, including the concentrating mill adjacent to the International smelter. All property to be sold as a single unit, to satisfy the mortgage in the amount of $1.3 million. (Ogden Standard Examiner, February 19, 1924; Salt Lake Mining Review, February 29, 1924)
March 31, 1924
The property and assets of Utah Consolidated Mining Company were sold at a Sheriff's sale on the steps of the Salt Lake city and county building. The successful bid was for $1 million, and came from International Smelting Company, a subsidiary of Anaconda Copper Company. (Salt Lake Telegram, March 31, 1924)
March 20, 1924
Utah-Delaware Mining Company was incorporated in the State of Delaware. (State of Delaware, Delaware Division of Corporations, File 166222)
Utah Consolidated Mining Company was reorganized as the Utah Delaware Mining Company, a full subsidiary of International Smelting Company, the Utah operating company of Anaconda Company.
March 12, 1937
National Tunnel and Mines Company was a merger of Utah Apex and Utah Delaware mining companies.
"UTAH MINING FIRMS AGREE UPON MERGER -- Utah-Apex, Utah-Delaware Plan To Resume Operations -- PORTLAND, Me., March 12. (AP) — Stockholders of the Utah-Apex Mining company voted here today to merge with the Utah-Delaware Mining company to form the National Tunnel and Mines company for operation of copper, lead and zinc mines in Utah and California." "Little more than an hour was required to effect the consolidation and elect officers under a previous joint agreement by respective boards of directors." "By the consolidation agreement, Utah Apex will be the surviving corporation, continuing under the name of the National Tunnel & Mines company. The new corporation will have authorized stock of 1,050,000 shares a without par value, 528,200 shares will be issued to the stockholders of Utah Apex in a share-for-share conversion plan. 328,000 will be issued to the holder of outstanding shares of Utah-Delaware, Inc., International Smelting and Refining company in conversion of a like number of fully paid and non-assessable share of Utah-Delaware now outstanding. The remaining 200,000 shares of the new corporation will be issued in conversion of a like number of partly-paid shares of Utah-Delaware Mining company, for which the Anaconda Copper Mining company has subscribed at the rate of $5 per share." "SHUT DOWN IN 1932 -- Properties of the two companies were shut down in 1932 because of the low price in metals." "The agreement proposed construction of a 22,000-foot drainage it and transportation tunnel through the joint properties." (Ogden Standard Examiner, March 12, 1937)
Utah Apex was shown as a subsidiary of Anaconda Copper Mining Company. (Lewiston [Maine] Daily Sun, March 12, 1937)
Work began on the construction of what would later be named the Elton Tunnel, to replace the aerial tramway. The tunnel was a project of the National Tunnel and Mines Company, a subsidiary of International Smelting Company, which also controlled the Utah Delaware Mining Company and the Utah Apex Mining Company.
December 6, 1940
National Tunnel and Mines was shown as being a subsidiary of Anaconda. (Salt Lake Tribune, December 6, 1940)
August 21, 1941
The Elton Tunnel was formally opened during a ceremony on August 21, 1941. The tunnel was named for J. O. Elton, general Manager of International Smelting & Refining Company, and its National Tunnel and Mines Company subsidiary which built the tunnel. The capacity of the tunnel was said to be 1000 tons per day. (Deseret News, August 21, 1941, "today")
The International smelter stopped smelting copper in 1946. (Deseret News, November 5, 1971)
Copper mining ended in the Carr Fork mine when World War II era government subsidies ended. (Desert Magazine, December 1948, citing the Salt Lake Tribune)
October 4, 1948
"The holdings of the National Tunnel and Mines company were sold at auction October 4, to the Anaconda Copper company for $500,000. The properties, including the Elton tunnel, buildings and more than 5000 acres of patented mining claims, had been estimated to have a value of $6,000,000. The 23,000-foot tunnel, running eastward from Tooele to connect with the workings of the Apex and Highland [Boy] mines on the Bingham side of the Oquirrh mountains, was completed in 1941. In addition to draining 2500 gallons of water per minute from the mines, 800,000 tons of ore were moved through the tunnel during World War II. When government subsidies on copper and lead were dropped, it was said, the ore was not of high enough grade to pay for its mining." (Desert Magazine, December 1948, page 30, citing the Salt Lake Tribune)
The Anaconda Company and American Smelting, Refining & Mining Company formed a joint venture for their Park City mining properties. The new company would be known as United Park City Mines Company, and would be a merger of the Park City district's two largest mining companies, the Park Utah Consolidated (which included the pioneer Ontario claim) and the Silver King Coalition. From 1953 through 1970, the focus was on mining, with a small side line of a small resort developed in late 1963. In 1970, The Anaconda Company and ASARCO formed Park City Ventures and leased all mining properties of United Park City Mines Company in the district. After Park City Ventures ceased operations in 1978, Noranda Mining Company leased the Ontario mine from 1979 to 1982, and was the last company to operate a mine in the district.
On May 18, 1955
The Anaconda Copper Mining Company was changed to The Anaconda Company. (Anaconda, by Isaac F. Marcosson, 1957, page 310)
July 12, 1963
Anaconda and Kennecott announced an agreement that would allow Anaconda access to its property adjoining the northwest rim of Kennecott's open pit mine, to allow Anaconda to begin core drilling and exploration of its property. Earlier core drilling by Anaconda had sunk exploration core holes below the bottom of Kennecott's open pit mine, at 5,490 feet. During earlier discussions, Anaconda and Kennecott had tried to reach an agreement about Kennecott expanding its open pit mine into Anaconda property to allow Kennecott access to ore bodies still on Kennecott's side of the property line, but talks had been stalled for several years. To continue expansion, Kennecott then made an agreement with United States Smelting, Refining & Mining Company for access along the south and southeast rim of Kennecott's open pit mine. (Salt Lake Tribune, July 12, 1963)
March 27, 1964
Kennecott and Anaconda reached an agreement to allow Kennecott to use portions of the old county road up Carr Fork to Highland Boy for its expanded pit operations, including truck haulage roads. The ownership of the surface ground, and the underlying mining claims, was dovetailed across the county road, with some already in Kennecott ownership, and some in Anaconda ownership. The settlement gave Kennecott surface rights to build and maintain its roads. Kennecott had filed an eminent domain suit to gain access to the surface rights in November 1963, but the parties settled the law suit. (Salt Lake Tribune, November 28, 1963; March 27, 1964)
July 11, 1965
Richard M. Stewart was appointed as the new manager of Anaconda's properties in Utah and portions of Nevada. This included the International smelter, the Tooele Valley Railway, "the inactive copper holdings near Bingham Canyon, several inactive lead, zinc and silver properties in the Tintic Mining District, and interests in the mining operations of the United Park City Mines Co." The International smelter was processing custom ores from many of Utah's small mining operations, and Stewart would be working with these mines to increase production. (Salt Lake Tribune, July 11, 1965)
July 20, 1967
Anaconda announced the creation of a new research department for all of its interests in the North and South America. The new department would be headquartered in a new building that Anaconda would soon complete at 1849 W. North Temple in Salt Lake City. (Salt Lake Tribune, July 20, 1967)
Drill exploration started for what would soon be known as the Carr Fork Mine, made up of the Yampa and Highland Boy properties. (Mining, Smelting and Railroading in Tooele County, page 77)
November 12, 1971
"Last week, the Anaconda Company announced it was closing its International Smelting and Refining Co. lead smelter at Tooele." United States Smelting Refining and Mining Co. announced it would close its mining and milling operations "before the end of the year." The United States company employs 410 men, and the International smelter employs 437 men. The United States company had an estimated 500 miles of underground tunnels near the open pit copper mine of Kennecott Copper Corp., and had been losing money on its Utah operations over the past two years, reaching a million dollars in the first half of 1971. (Ogden Standard Examiner, November 12, 1971)
January 28, 1972
The smelter of International Smelting and Refining Company was scheduled to close on January 1, 1972, but reduced production work continued for another three weeks. On January 28, 1972, the Tooele Valley Railway made it last run between the smelter and the interchange at Warner. Throughout its history, the railroad had made the trip at least twice daily. The last trip was made with only a single boxcar and a caboose. The boxcar had been used to bring the last load of newsprint paper for the Tooele Transcript newspaper. (Tooele Transcript, February 11, 1972)
Operations on the Tooele Valley Railway continued after the International smelter was closed. Until about 1975, the railroad was used to ship outgoing scrap from the dismantling of the smelter, and until 1981, the railroad was used to accept inbound shipments of construction materials for the development of the new Carr Fork Mine. (Mining, Smelting and Railroading in Tooele County, page 118)
Tooele Valley Railway was used to haul away the scrap as the International smelter was torn down in 1972-1974, and remained to move inbound material for the construction the new Carr Fork mine and mill in Pine Canyon. It was finally shut down and abandoned when Anaconda's Carr Fork Project mine and mill shut down, with its last day of operation being on August 28, 1982.
Carr Fork Project
The following comes from Ken Krahulec's "History And Production Of The West Mountain (Bingham) Mining District, Salt Lake County, Utah," published in 1998.
The 1970s also brought a reappraisal of Bingham Canyon's deep copper-gold skarn potential. This resulted in Anaconda's decision to develop the Carr Fork copper skarn, on the down-dip projection of the old Highland Boy-Apex mines, which had closed in 1947. By 1974 Anaconda had tested the deposit with 17 deep surface holes from their property on the northwest flank of the open pit copper mine. After five years of development, the Carr Fork mine began production in August 1979. The mine only operated for slightly over two years, however, before high operating costs, dilution, shaft problems, and low copper prices forced its closure.
Similarly, Kennecott Copper re-examined the North Ore Shoot copper-gold skarn to the northeast of the pit. The deposit was discovered in 1957 and initially delineated by 24 surface holes drilled over the next 15 years. A 20-foot diameter shaft was completed to a depth of 3,089 feet in 1983. The deposit was further explored by 12,300 feet of drifting, three test stopes, and 72,848 feet of drilling in 124 underground holes. The North Ore Shoot has yet to begin production, and both the Carr Fork and the North Ore Shoot mines are now flooded.
September 7, 1974
Anaconda announced a new project to begin mining copper from a new underground mine to be located about two miles west of Kennecott's Bingham open pit mine. The project was to cost $136 million, and the new mine would produce 56,000 pounds of copper per year, beginning in 1979. Development work was to begin immediately, with the new mine to be 2,000 to 5,000 feet below the surface. Concentrates from the 10,000 tons per day concentrator mill would be shipped to Anaconda's copper smelter in Anaconda, Montana. Anaconda had been exploring the potential mine since 1969, when the ore body was first discovered. The ore body would be mined using the room-and-pillar method, using heavy machinery and methods similar to those being used in many coal mines. Waste rock would be removed from the mine and dumped at the site of the now-retired International smelter site, and existing road and railroad facilities would also be used. (Ogden Standard Examiner, September 7, 1974)
(A monument at the site shows September 6, 1974 as the project start date, and August 31, 1979 as the date of first production.)
August 12, 1975
Anaconda announced that it would halt work on shafts No. 1 and No. 3, two of the four shafts it was excavating as part of its Carr Fork underground mine. Although the mine was still planned to be in operation in 1979, its capacity would be reduced from 10,000 tons per day, to 5,000 tons per day. (Provo Daily Herald, August 12, 1975)
(Photos taken in August 1975 show the headframe of the exhaust shaft for its Carr Fork mine on Anaconda property on the north side of what was formerly Carr Fork canyon, but by that time was simply the north slope of the Bingham open pit mine. The headframe and hoist building were about 1,000 feet up-canyon from the Kennecott observation platform, which is visible in the photos. The headframe was removed when the vertical shaft reached the desired depth, and replaced by a large exhaust fan.)
In January 1977, Atlantic Richfield Company (ARCO) purchased the all interests of Anaconda Copper Mining Company.
March 21, 1978
Work resumed on Anaconda's Carr Fork underground mine. Work resumed on the drilling and excavation of a ventilation shaft following work being suspended earlier in the month due to the deaths of two workmen. Work on the ventilation shaft had begun a year earlier, and was to be completed in two months. (Deseret News, March 21, 1978, "today")
December 18, 1978
Anaconda announced that its Carr Fork underground mine would begin production in September 1979.
Anaconda's Carr Fork mine took delivery of five new 30-ton electric mining locomotives from General Electric in June and July 1979. These were intended to be used in the underground operations, but from information provided during their sale at auction stated that all five locomotive had never been used. (email correspondence with Robert Lehmuth, May 27 to May 30, 2011, citing GE builder records, and a sales brochure from the D'Angelo auction house)
(A monument at the site shows September 6, 1974 as the project start date, and August 31, 1979 as the date of first production.)
Anaconda began production from its Carr Fork underground mine. (Deseret News, November 2, 1984)
September 29, 1980
Anaconda Copper Mining Co. announced that it would close its smelter at Anaconda, and its refinery at Great Falls, both in Montana. (Eugene Register, September 29, 1980; Deseret News, September 30, 1980
The Carr Fork mine stopped production in November 1981, while Anaconda waited for copper prices to rise. When this did not happen, the processing facilities were torn down, sold, and removed from the property in late 1984.
October 7, 1982
Anaconda closed its Carr Fork underground mine, after just three years of operation. The move laid off 120 workers, leaving 50 employees to maintian the equipment, including keeping the pumps running to remove water from the underground shafts. A year before, there had been 900 workers as part of the Carr Fork Project. (Tooele Transcript Bulletin, October 7, 1982)
January 6, 1983
Anaconda announced that they would close the Butte copper mine, effective June 30, 1983. (Sarasota Herald-Tribune, January 8, 1983, Associated Press news item)
May 14, 1984
A large mudslide hit the surface works of Anaconda's Carr Fork mine in Pine canyon, killing one worker who was operating a bulldozer at the time. The slide also filled the service shaft located the the top of the canyon, the major access to the underground workings. Three days later, Anaconda shut down all operations and laid off all but eight workers, essentially closing the project permanently. The worker was clearing the debris from an earlier slide. The slide also cut off power to the service shaft and other buildings in the vicinity. (Tooele Transcript Bulletin, May 17, 1984; May 29, 1984)
November 1, 1984
Kennecott and Anaconda announced a joint venture that would resume production from Anaconda's Carr Fork underground mine. Kennecott was to be the operator and would receive 96 percent of the production, with Anaconda receiving the remaining four percent. The Carr Fork concentrator had a 10,000 tons per day capacity, but the mine never reached that number in its production. (Deseret News, November 2, 1984)
In 1985, Anaconda sold the last of its copper and molybdenum property and operations and became solely a coal mining company. Beaver Creek Coal Co., was shown as its only operation in Utah. (Coal Age, Volume 90, Number 6, June 1985, page 24)
"Before Kennecott purchased Anaconda the north west corner of the mine levels were so tight it was hard to get locomotives and cars around the levels. From about 5940 elevation up to 6240 elevation we could plan on having a derailment in that area daily." (Gary C. Curtis, posted to Bingham Canyon History group on Facebook, May 22, 2018)
"New York -- Kennecott, Salt Lake City, has purchased a portion of the Carr Fork, Utah, copper mine from Anaconda Minerals Co., Denver. The deal alters an original plan announced late last year between the two producers to jointly operate their Utah copper mining properties. "The purpose of the direct purchase was to give us flexibility in any future mining of the ore reserves which lie along the western boundary of our property," a Kennecott spokesman said." (American Metal Markets, October 3, 1985)
Specifically, the Anaconda interests that were purchased by Kennecott was the controlling 86 percent ownership of New Bingham Mary Mining Company, which adjoined Kennecott's property. New Bingham Mary had been organized in 1929, but very little activity took place until August 1978 when Anaconda was able to purchase its 86 percent ownership of New Bingham Mary stock. Through its majority ownership, Anaconda caused a lease to be assigned to itself, and the ore body was developed and worked from August 1979 to November 1981, solely by underground methods. In September 1985, Kennecott bought all of Anaconda's shares of New Bingham Mary. In November 1987, Kennecott assigned the previous Anaconda lease to itself, and began stripping overburden from the ore body, and mining the ore body by open pit methods. In 1997, the Kennecott-controlled management proposed to merge New Bingham Mary into Bingham Consolidation Company, a wholly owned subsidiary of Kennecott. The merger of the two companies into a new Bingham Consolidated Company was completed on January 1, 1998. (Bingham Consolidation Company vs. Groesbeck, Utah Court of Appeals, November 26, 2004)
ARCO After Anaconda
The following comes from the Wikipedia article about Anaconda after ARCO:
At the time of the sale to ARCO, Anaconda had large working hard coal holdings in the Black Thunder mine at Thunder Basin, Wyoming. ARCO planned to diversify its energy business into coal. In June 1998, Arch Coal completed the acquisition of the coal assets of Atlantic Richfield. Closing down the mines was not the end of the new owner's problems. The areas of Butte, Anaconda, and the Clark Fork River in this vicinity became highly contaminated by mining and smelting operations. Milling and smelting produced wastes with high concentrations of arsenic, as well as copper, cadmium, lead, zinc, and other heavy metals. Beginning in 1980s, the Environmental Protection Agency designated the Upper Clark Fork river basin and many associated areas as Superfund sites—the nation's largest. The EPA named ARCO as the "potentially responsible party." As a result, ARCO was obliged to remediate (clean up) the area. Since then, ARCO has spent hundreds of millions of dollars decontaminating and rehabilitating the area, though the job is far from finished. ARCO merged with BP in 2000. BP in turn sold most of ARCO (retail network in US Southwest states) to Tesoro in 2010. (Anaconda on Wikipedia)
The following comes from the Britannica article about ARCO after Anaconda:
During the 1980s and '90s the company reversed its diversification efforts in order to refocus on its historical strength in petroleum. By the end of the 20th century, Atlantic Richfield had sold off all or most of its minerals, coal, petrochemical, and solar energy assets. It had petroleum operations in all parts of the United States as well as in Indonesia, the North Sea, and the South China Sea. The company also owned and operated transportation facilities for liquid petroleum, including pipelines and tankers. The acquisition of Atlantic Richfield by BP Amoco in 2000 for $27 billion doubled the British company's share of natural gas in Prudhoe Bay and made BP the second largest oil company in the world. (ARCO at Britannica.com)
"Phillips Petroleum Co. agreed Wednesday to buy Atlantic Richfield Co.'s oil-producing assets in Alaska for $7 billion, clearing away a top concern of federal officials who had sought to block BP Amoco's $27 billion buyout of Arco for antitrust reasons." (CNN Money, March 15, 2000)
Arco (as a subsidiary of BP) remains as the primary responsible party in the environmental cleanup of both the International smelter site near Tooele, Utah, and the Anaconda smelter site at Anaconda, Montana. In the 2016 and 2017 time period, several agreements, settlements, trust funds and contingency funds were established to ensure the long-term care, monitoring and and mitigation of the sites. Having BP as a parent company has eased the financial future for the proper care of these various former mine and smelter sites formerly owned and operated by the Anaconda company.
New Bingham Mary
Throughout the 1960s into the 1980s, the north slope of Kennecott's Bingham open pit mine was unbroken and contained large patches of green hill side, looking much as it did from the early days of the mine. The reason was that Kennecott only held surface rights to the north slope, for dumping and for trackage rights, but no subsurface rights that would allow it to extract ore.
Although the name of Bingham Mary, and later New Bingham Mary were among hundreds of mining companies at Bingham, the property was unique because it was at the boundary between two giants, Kennecott and Anaconda. Kennecott owned the portions of Bingham Canyon south and east of the former site of the town of Highland Boy, situated at the top of Carr Fork, a major side canyon of the larger Bingham Canyon. Anaconda owned the north and west portions, essentially the north slope of Carr Fork, and the ridge between Bingham Canyon and Tooele. And the New Bingham Mary lay between the two.