Railroads and Mining in Utah's Bingham Canyon, Copper Era 1989 to Today
Index For This Page
This page last updated on November 3, 2023.
(Return to Bingham Index Page)
Copper Era, From 1989 to today (Rio Tinto)
(Read a brief summary of Kennecott history, through 1995; courtesy of Jim Harrawood's now-abandoned UtahRails.com web site)
(Read a brief summary of Kennecott history at Utah History Encyclopedia, published in 1994)
1989
With the completion of the new Copperton mill, production for the Bingham mine was reported as: 111,000 tons of ore mined per day; 99,200 tons of waste rock moved per day; 210,000 tons of copper produced in 1989.
During 1989 there were five ore shovel faces, and five waste shovel faces being worked to maintain production. The majority of the ore was located in the bottom 900 feet off the mine, below the 5740 Level. The upper-most waste removal was taking place at the 7740 level. (Jeffery D. Tygesen, "Porphyry Copper: Bingham Canyon Mine", Society for Mining, Metallurgy and Exploration, SME Mining Engineering Handbook, Second Edition, Volume 2, 1992, ISBN -0-87335-100-2)
January 1990
The new parent company, RTZ Corporation, announced that it would spend $227 million to expand the Utah operations of its Kennecott Corporation subsidiary. The expansion would increase the Copperton mill's production by 35,000 tons of copper ore per day, from 77,000 tons per day, to 112,000 tons per day, and was in addition to the current 30,000 tons per day being processed by the North Concentrator Complex (the Bonneville grinding mill and the Magna concentrating mill). The annual production of finished copper would be increased from 235,000 to 270,000 tons per year. The increase was made possible by using state-of-the-art technology, and by improved economies of scale for the overall mine operations. (Deseret News, January 4, 1990; New York Times, January 15, 1990)
The improvements included:
- Expansion of the coarse ore stockpile at the Copperton mill
- Addition of a four grinding line at the Copperton mill
- Addition of a new floatation circuit at the Copperton mill
- Expansion and upgrade of the existing molybdenite recovery plant at the Copperton mill
- Addition of a fourth filter press at the Garfield smelter
May 1990
As part of an effort to remove unnecessary facilities, and improve overall safety, RTZ removed the overhead bridge between its Garfield smelter south of State Route 201, and the slag disposal "hill" on the north side of the highway. The bridge formerly supported the electrified railroad that was used for slag disposal, but had not been used following the modernization of the entire smelting process in 1987-1988.
1991
After being closed since 1984, the Arthur concentrator complex was demolished during 1991. (Salt Lake Tribune, May 11, 2007) (The adjacent Magna concentrator was closed in 2001, and demolished in 2007)
Kennecott expanded the capacity of the Copperton concentrator, adding a fourth crushing and grinding line. The intent was that the Copperton operation would replace the North Concentrator Complex, which had been restarted in September 1986, following the suspension of all operation at Bingham in 1985.
1992
Kennecott mined a total of 142,000 tons per day during 1992. (Jeffery D. Tygesen, "Porphyry Copper: Bingham Canyon Mine")
(Read more about Kennecott in 1992)
1992
"The Copperton concentrator was expanded in 1992 and fitted with some of the world's largest Semi-Autogenous Grinding (SAG) and ball mills, and large flotation cells. There are four grinding and flotation lines, sequentially yielding a copper and molybdenum concentrate. The copper concentrate is piped about 27km to the smelter. Until its closure in mid-2001, the older North plant supplied about 20% of the copper concentrate for smelting." (Mining Technology.com)
April 27, 1992
The Bingham Canyon visitors center was re-dedicated after a new access road was completed during the winter of 1991-1992. The new access road was constructed from a new entrance gate at the old location of the Lark townsite, climbing northward across the face of the waste dump area to an expanded parking lot. After the new access road to the new visitors center was opened in April 1992, Utah Route 48, the state road in Bingham Canyon, was decommissioned and abandoned. The roadway and right-of-way west of Copperton became private property of Kennecott.
March 11, 1992
Kennecott announced a $900 million expansion project that was to modernize its Garfield refinery, and build a new high-tech flash-converting smelter, just east of of its existing smelter at Garfield. The new smelter would the cleanest copper smelter in the world, capturing 99.9 per cent of the sulfur contained in copper concentrates, or just 200 pounds of sulfur dioxide per hour, said to be just 1/20th of the 4,700 pounds per hour allowed by current Utah environmental laws. (The current smelter only captured 93 per cent of the sulfur.) The new smelter would also generate 85 per cent of its own energy, and would use only 1/4 of the energy used by the current smelter to produce one ton of finished copper. The new flash-converting smelting process smelter would replace the current smelter, after which the existing smelter would be dismantled. The expansion project was planned to be completed within three years, by 1995, and would allow Kennecott to process all of its copper concentrate. Currently, Kennecott is shipping 40 per cent of its copper concentrate out of the state, mostly to Japan. (Deseret News, March 11, 1992)
March 1992
Kennecott Utah Copper Corporation (KUCC) became a unit of RTZ Corporation (England). It is reported that a new smelter would be built with a completion date set for 1995. At present, 40 percent of the mine's output is exported for processing. The new smelter will change the amount shipped out for processing. (Wall Street Journal, March 12, 1992)
March 1992
The capacity of the Copperton concentrator was increased to 112,000 tons per day. "Commissioned in March 1992, the Copperton concentrator expansion project increased its nominal capacity to 112,000-stpd. In 1992, a three-year program was initiated to replace the existing smelter facility with a new Outokumpu flash converting smelter. This project also included a double contact acid plant, cogeneration power plant, modernization of the existing copper refinery and a new precious metals refinery. It was completed in June 1995 at a total cost of US $1.1 billion." (David F. Briggs, Mining Operations Report, Bingham Canyon, June 2005)
"The Copperton Concentrator was completed in 1988. Modernization and expansion of the facility was completed in 1992 and was designed to process a capacity of 142,000 tons of ore per day. Ore is transported from the Bingham Mine via a conveyor belt to the coarse ore stockpile. The ore is fed to Semi-Autogenous Grinding (SAG) mills which crush the ore for separation and floatation to concentrate metal recovery. Tailings are slurried via a 13 mile pipeline to the tailings impoundment adjacent to the Great Salt Lake." (Utah Water Quality Report, 2009)
November 1993
Kennecott announced a $510 million expansion to its tailings pond, expanding the existing pond. The expanded tailings pond will be built on land acquired from Morton Salt Company "several years ago." The expanded pond was to be completed by 1998. (Salt Lake Tribune, November 4, 1993)
March 9, 1994
Kennecott received the approval of the Salt Lake County Planning Commission for the design if its expanded tailings pond. (Salt Lake Tribune, March 9, 1994)
March 16, 1994
Later negotiations with Salt Lake City and Salt Lake County reduced the size of the planned tailings pond expansion, by removing the eastern one-mile portion, which was within Salt Lake City limits. Salt Lake City had numerous concerns about the expanded tailings pond, and this reduction completely removed Salt Lake City from the permitting process. (Deseret News, April 29, 1994)
March 24, 1994
Kennecott awarded a contract to Morrison Knudsen for the construction of the new $500 million tailings impoundment expansion. Initial work had begun in October 1993, with a completion date of late 1998. The expansion would add six square miles to the present tailings pond. When completed, the new impoundment would be 230 feet high. (Morrison Knudsen press release dated March 24, 1994)
1994-1995
As part of the expansion of the tailing pond, Kennecott bought the property of the former Chevron Chemical phosphate fertilizer plant:
Chevron Fertilizer Plant: Located just north of the pre-1997 South Tailings Impoundment and mostly buried by the North Tailings impoundment was the Chevron Fertilizer Plant and its wastes. The plant, built in 1952, was originally a joint venture of Kennecott, ASARCO, and Stauffer Chemical. The plant treated phosphate ores with sulfuric acid to produce phosphoric acid and dry phosphate fertilizer products. Annual production ranged between 10,000 and 70,000 tons/year. Wastes included 300,000 tons/year of phosphogypsum. Chevron bought the facility in 1981. They ceased production of the phosphoric and acid and dry phosphate in 1986. Then they leased the land to FCI Agri-chem who mined the phosphogypsum tailings at the site for use as soil additives. The wastes covered about 385 acres and was thought to be about 6 million cubic yards. Kennecott bought the land in 1994 for use in the North Expansion and dismantled the plant in 1995 retaining only the administration building. There were 4 above ground fuel oil storage tanks that were removed and contamination in the footprint excavated and placed in a land farm at the site. There were also reports of the burial of Picloram at the site, but an investigation did not find any traces of this pesticide. (Kennecott.com -- Record of Decision, North End)
1995
During 1995, Kennecott built a pilot plant to test the Solvent Extraction/Electrowining process. The pilot plant, was located at Dry Fork and was closed in 1998. In 2008, a new Solvent Extraction/Electrowining plant was constructed at Copperton, and replaced the existing precipitation plant. (Utah Air Quality Control Board comment sheet dated August 4, 2008)
April 1995
Kennecott's 300,000-tons-per-year copper smelter had been completed by mid April 1995 and began its testing phase, with limited production expected to begin in May. When full production starts, in June or July, the old smelter will be demolished. The old smelter used old technology that used open blast furnaces to convert copper concentrate to copper matte, using large overhead cranes and ladles to move the molten copper matte from the furnaces to cast the copper matte into anodes, which were then transported by rail car to the refinery. The new smelter would reduce smelter operating costs by 53 per cent, and changes to the refining process would reduce refining costs by 45 per cent. The resulting copper would be 99 per cent pure. The modernization of the smelter and refinery would allow Kennecott to process all of the copper ore being produced by the Bingham Canyon mine. (Salt Lake Tribune, March 22, 1995; April 16, 1995)
Problems getting the various parts of the new and complex smelting process to work together, forced the smelter to operate at 80 to 85 percent capacity until early 1997. The reduced capacity meant that Kennecott had to sell come of its copper concentrate to other smelters, and to begin stockpiling concentrate pending the smelter's return to full capacity. The new smelter had been commissioned in July 1995. (Salt Lake Tribune, September 13, 1996)
April 26, 1995
The U. S. Army Corps of Engineers had contemplated its environmental assessment of Kennecott's planned expansion of its tailings pond. The expansion would increase the existing 5,700-acre tailings pond by an additional 3,500 acres. The Corps stated that the new pond would have minimal impact due to Kennecott's intent to replace 1,055 acres of affected wetlands, which were already highly degraded and of low habitat value due to the existing adjacent interstate highway and railroad tracks, with a new 2,500-acre nature preserve. Kennecott had purchased land along Great Salt Lake's south shore, northeast of the former Saltair beaches, which would be set aside as a formal nature preserve. (Salt Lake Tribune, April 26, 1995)
As part of the tailings pond expansion, in July 1996, Kennecott began the relocation of 8.2 miles of Union Pacific railroad mainline, moving the railroad line from its current location along the north side of the current tailings pond, north to a new alignment parallel to Interstate 80, and along the north edge of the planned expanded pond. Utah State Route 202, the 1-7-mile connector along the western edge of the existing tailings pond between State Route 201 on the south and Interstate 80 on the north, would be closed until April 1998 to allow construction equipment unimpeded access between the new tailings pond site, and material stockpiles adjacent to the smelter. (Deseret News, July 5, 1996) (Union Pacific began using the relocated tracks in mid June 1997; site preparation had begun in late summer 1995.)
September 21, 1995
Kennecott dedicated its modernized Utah smelter on September 21, 1995. The following is taken from the company's press release dated the same day.
Kennecott today dedicated the new $880 million smelter/refinery project at its Utah Copper operations near Salt Lake City. The smelter, the most technically advanced facility of its kind in the world, will produce 310,000 tons of refined copper per year — double the capacity of the previous operation.
When the new smelter is at full capacity in the first quarter of 1996...
This facility will be the cleanest smelter in the world. It is designed to capture 99.9% of the sulfur generated in the smelting process. Sulfur dioxide emissions will be less than five percent of the emissions from the old smelter and particulate emissions will be less than one-third the level permitted by the State of Utah. Initial results confirm this predicted reduction in emissions. In addition, the smelter will capture waste heat as steam and cogenerate about 85 percent of its electrical power needs.
The new smelter utilizes what is called "flash smelting" technology for the first step.
Copper matte (the molten copper metal from the flash smelting furnace) is quenched in water and granulated instead of being transferred by ladle and overhead crane. Granulation and storage of the matte provides for independent operation of both the smelting and converting furnaces, allowing each to operate at peak efficiency. Granulation of the matte also eliminates the transfer of molten metal between furnaces, which was a major source of emissions in the old smelter.
The second step of the process represents the first major application of the technology known as "flash converting." This unique technology was developed by Kennecott in cooperation with Outokumpu, a Finnish company and a leader in smelting technology. Flash converting has two basic environmental impacts. First, it allows for a greater capture of gases than the old process. Second, it allows the smelter's primary pollution control device — the acid plant -- to operate more efficiently.
The $880 million project also included the modernization and expansion of the Kennecott Utah Copper Refinery. This highly automated facility utilizes sophisticated robotic systems to handle the design capacity of 310,000 tons of refined copper. The refinery also includes a new precious metals facility to produce by-product gold and silver from the Bingham Canyon Mine.
The start up of the smelter/refinery completes the $880 million modernization project announced in 1992. Before construction of the new facility, Kennecott Utah Copper concentrate production exceeded smelting capacity and the company was exporting 40 percent of its copper concentrate. When the facility is running at full capacity, Kennecott Utah Copper will process all of its own concentrate at the Utah facility.
Since 1985, Kennecott has invested more than $1.5 billion to modernize the Utah Copper operations. The expansion of the tailings impoundment, at a cost of $500 million and scheduled for completion at the end of the decade, will complete the $2 billion modernization of the entire copper production process at the Utah facility.
Additional comments about the modernized smelter come from the February 5, 1999 issue of the Deseret News newspaper.
- In 1985-1992, Kennecott's Copperton mine and concentrator were modernized at a reported cost of $620 million.
- In 1992-1995, the smelter and refinery were modernized at a reported cost of $880 million, making for a total cost of $1.5 billion for Kennecott's 1985-1995 modernization programs.
- Flash smelting produced copper matte that is 70 percent pure; flash converting further converted copper matte to blister copper, which is 98.6 percent pure.
October 1995
Kennecott signed a contract with Union Switch & Signal Company for US&S to furnish a desktop computer-based rail traffic control system. The hardware of the new system was to include one dispatcher console and one system maintenance console. The dispatcher would be able to control wayside signals, switch machines and other wayside field equipment from the single console. The system would include centralized traffic control functions such as train tracking and entrance-exit routing. (US&S news release dated October 24, 1995)
November 1995
Kennecott's Bingham mine produced 97,000 tons of copper during the third quarter of 1995, compared to 89,000 tons produced in the same quarter of 1994. Gold production increased from 138,000 ounces to 183,000 ounces. (Salt Lake Tribune, November 14, 1995)
October 17, 1996
A brief two-day strike was called by the 1,800 workers belonging to 17 unions at Kennecott's copper mine, mills, power plant, smelter and refinery in Utah. The dispute was over pensions, medical coverage, work assignments and wages, and was resolved in a very short period. It was the first strike at Kennecott in 17 years. (Salt Lake Tribune, October 17, 18 and 19, 1996; Deseret News, October 17, 1996)
February 1997
The problems with getting the new smelter fully operational drove RTZ profits down 23.9 per cent, from $1.4 billion in 1995, to $1.1 billion in 1996, about half due to falling metals prices, and about half due to delays concerning the new smelter. The new smelter was expected to be fully operational by June 1997. (Salt Lake Tribune, February 28, 1997; Salt Lake Tribune, March 20, 1997)
March 1997
Effective April 1, 1997, RTZ was to close 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 the former BP 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 of the 220 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; Salt Lake Tribune, March 20, 1997)
May 27, 1997
Kennecott's new smelter was re-started after a six-week shutdown. Production was about 100 tons of copper anodes per hour, with each anode weighing 720 pounds, and being 99.5 percent pure copper. The anodes were then transported to the Utah refinery, where the copper was further refined to be 99.99 percent pure. (Salt Lake Tribune, June 12, 1997; Salt Lake Tribune, July 31, 1997)
June 2, 1997
RTZ Corporation changed its name to Rio Tinto. (Rio Tinto press release dated June 2, 1997)
The proposal was sent to shareholders in April 1997 as part of the 1996 annual report. The reason given was to do away with the confusing "alphabet soup" name of RTZ-CRA, derived from the names of the companies that were merged in October 1995.
- RTZ = Rio Tinto - Zinc
- CRA = Conzinc Riotinto of Australia
The original Rio Tinto Company dates from 1873. In 1962, Rio Tinto Company merged with the Australian firm Consolidated Zinc to form the Rio Tinto – Zinc Corporation (RTZ) and its main subsidiary, Conzinc Riotinto of Australia (CRA). Consolidated Zinc was an Australian mining company dating from 1949, with its predecessor company, Zinc Corporation, dating from 1905. (Wikipedia)
October 1998
The price of copper was at 70 cents per pound, down from $1.10 per pound in January 1997. (Salt Lake Tribune, October 27, 1998)
June 1999
Kennecott applied to the Utah Division of Air Quality to allow its Bingham Canyon mine to increase production of waste rock and metal ore at the Bingham Canyon mine, from 150 million tons per year to 197 million tons per year. The increased production would result in an increase of regulated dust, known as PM10. (Salt Lake Tribune, June 15, 1999; Deseret News, June 27, 1999)
July 1999
A summary of the modernized Utah smelter was published in the July 1999 issue of Mining Engineering, published by the Society of Mining Engineers (SME). The following highlights are taken from the article.
- Before 1995, the smelting process at the Kennecott Utah Copper Corp. (KUCC) smelter consisted of Noranda reactors and Pierce-Smith converters. When considering expansion, it was decided that the existing process would not lend itself to a program geared toward processing the total output of copper precipitate and copper concentrate from KUCC mining and concentrating operations.
- The smelter facility that used the Noranda technology was shut down in May 1995. The flash smelting furnace operation began in June [1999] with the flash converting furnace startup a few weeks later.
- Initial expansion of the KUCC Bingham Canyon Mine and Copperton concentrator facilities was completed in 1988. Production rates increased to 852,000 tons per year of copper concentrate. In 1992, a fourth milling circuit was added to increase concentrate production to 1.1 million tons per year. At that time, KUCC's smelter could process only about half of the concentrate production because of insufficient gas-handling and acid-plant capacity to meet air emission regulations. As a result, the rest of the concentrate production was sold.
- In 1989, KUCC began a study of smelting requirements to process all of the available concentrate resulting from the expansion of mining and milling facilities and also future expansions.
- In 1990, the Outokumpu flash-smelting process was chosen as the primary smelting vessel, to be combined with Kennecott-Outokumpu flash-converting technology to process solid matte through to blister copper. These two processes best met the primary criteria of achieving the identified annual throughput, complying with environmental requirements and positioning the smelter for future anticipated, more restrictive, emission requirements.
- In the spring of 1991, full-scale tests were carried out using 3.5 kt (3,850 st) of KUCC concentrate to confirm impurity deportments. These tests were performed at the Outokumpu smelter at Harjavalta, Finland. Matte produced was granulated and ground to the required size for subsequent conversion to blister copper in Outokumpu's pilot furnace at the Pori Research Center. This test work confirmed the selection of flash smelting and flash converting for the modernized KUCC smelter. Engineering was started and the basic layout and design were completed in early 1992.
- The smelter expansion required a modernization of the KUCC copper refinery. This included installing the Kidd Process, using stainless steel electrodes. An innovative hydrometallurgical process was also installed to recover precious metals from tankhouse slimes.
- The strategy developed for the modernized smelter was to install the best available emission-control equipment to meet stringent environmental regulations and minimize the need for progressive modifications to the facility in the future.
- The permit limits for the modernized smelter are low by contemporary standards for smelters. The modernized KUCC smelter was designed and constructed to be the "cleanest" smelter in the world, with a sulfur capture of 99.9%. The new air-permit approval was received in April 1993, less than five months after the initial submission. Construction began in early 1993 and was completed by May 1995.
- The Flash smelting furnace began commercial smelting operations of copper concentrate on June 13,1995, and as of 1999 was producing 225 dry-tons per hour of gradulated 70-percent copper matte.
- The Flash converting furnace began commercial converting operations on July 4,1995, and as of 1999 was producing 82 tons per hour of 98.6 percent copper matte.
- After a planned shut-down in April and May 1997 for repairs and upgrades, portions of the processes across the smelter were improved.
- After the 1997 upgrade, the anode plant had a capacity of 110 tons per hour of finished copper anodes to be transported by rail cars to the copper refinery.
- (Read a simplified, edited text version of the July 1999 Mining Engineering article)
September 1999
During the period between 1999 and 2005, Kennecott would need a place to dump 400 to 600 million tons of waste rock. The best candidate was to fill in Bingham Canyon itself, but there was a set of railroad tracks in the way. By way of the 5840 railroad tunnel, these tracks connected the last in-mine reload station with tracks that took ore trains to the North Concentrator at Magna. Plans were put into place in September 1999 to relocate the reload station from inside the mine, to a point just below Dry Fork Shops. The move was estimated to cost about $8 million, but the payoff was projected to be $30 million. The move was originally scheduled to be completed in 2004, but in September 1999 plans were made to move the reload station in 2000. (Kennecott employee newsletter, dated September 8, 1999)
Fall 1999
Kennecott had two concentrators during 1999. A new concentrator was built at Copperton, completed in 1988 it was supplied by a conveyor belt directly from the pit, and the Magna mill and concentrator became known as the "North Concentrator," which was supplide by rail. The mainline railroad continued to operate as long as the North Concentrator was operating. When the North Concentrator was shut tempoarily in mid 2001, then permanently six months later, it was the end of the rail operation to Copperton.
March 2000
The reload facility in the mine was moved to a site below Dry Forks shops. The previous reload site was inside the pit, accessed via rail through the 5840 tunnel, and had been found to be located on top of a pocket of high grade ore. Moving the reload site outside of the mine also allowed the 5840 tunnel to be closed. The rail in the 5490 tunnel had been replaced in January 1988 by a new conveyor belt that moved ore from the primary crusher in the pit, out to the new Copperton concentrator.
March 19, 2000
The last ore train was operated from the last reload site inside the mine, through the 5840 tunnel, down the remaining rail corridor in old Bingham Canyon to Copperton yard. After that date, all ore was loaded at the new Dry Fork reload site, outside of the mine. (Louie Cononelos, email dated December 27, 2011)
During May 2001, there were three or four trains per day between the mine and the mills. (Steve Ellis, Trainorders.com, May 21, 2001)
May 30, 2001
The last ore train was moved from the Dry Fork reload site at Bingham, to the Bonneville crusher. All later moves over the former Ore Haulage mainline were to transport new sections of the conveyor belt between the rail interchange with Union Pacific at Garfield, and Copperton, where Kennecott was marshalling supplies for conveyor maintenance. (Ken DeLuca, email dated December 27, 2011, citing an earlier internal document compiled on September 5, 2008)
Sections of the conveyor belts were replaced during 2001 and 2002 as production downtime was scheduled for other equipment at the mine, including the relocation of the primary crusher in the mine itself.
June 1, 2001
Kennecott shut down the original Magna mill. In its news release dated May 25, 2001, Kennecott gave the reason for the closure as a reduction of operating costs and improved efficiencies. During 2000, Kennecott had shipped 30,000 tons of copper concentrate to independent refineries and smelters because its mills were producing more concentrate than Kennecott could process in its Garfield smelter. (Kennecott news release, dated May 25, 2001)
Kennecott To Curtail Operations
Magna, Utah -- May 25, 2001 -- Kennecott Utah Copper Corporation (KUC) will start to suspend operations at its North Concentrator Plant on or about June 1. Associated rail haulage operations will also be curtailed. The curtailment will impact about 235 hourly and salaried employees, and will reduce KUC's annual ore production by about 18 percent. Worker Adjustment and Retraining Notification Act notices were issued on May 25 announcing the curtailment.
According to Bruce Farmer, Kennecott's president and CEO, "The action is in response to difficult market conditions and the need to improve the Company's business performance. Our costs are too high and the closure of the higher cost, older North Concentrator Plant, will help reduce our costs over all. This action will be only a part of an ongoing drive to reduce costs and improve efficiencies." In the last three years, continuing low copper prices and increased costs of production have resulted in United States copper production being reduced by more than 33 percent.
"Kennecott regrets the impact that this necessary action will have on employees. To minimize this impact, the Company is discussing an enhanced early retirement for eligible hourly and salaried employees. Meetings have been held with union officials to discuss the proposal for hourly represented employees. An early retirement program also will be offered to eligible salaried employees. We are hopeful that the loss of jobs can be minimized through attrition," said company spokesman Louie Cononelos. He added that the Company believes that the proposed enhanced retirement plans and the reassignment of personnel should reduce the number of involuntary terminations.
The North Concentrator is Kennecott's oldest plant. Its Bonneville Crushing and Grinding facility was built in 1966, and its Magna Flotation facility was upgraded in 1982. Following completion of Kennecott's Bingham Canyon Mine and Copperton Concentrator modernization in 1988, the North Concentrator was to be closed, but its operations were continued because of high copper prices. In 2000, KUC sold approximately 30,000 tons of copper in concentrate produced from the North Concentrator to independent smelting and refinery facilities because it was unable to process it on site. According to Farmer, KUC's smelting and refining production will be maximized as the Company reduces operating costs and improves efficiencies.
November 2001
In June 2001, operations at the North Concentrator Complex had been temporarily suspended, but on November 27, 2001, Kennecott Utah Copper announced that it would close the North Concentrator Complex permanently.
November 27, 2001 - Rio Tinto's wholly owned Kennecott Utah Copper Corporation (KUC) today announced several steps to cut costs and improve productivity to help secure its future. KUC will permanently close its North Concentrator and make consequential changes to its mining operations as well as outsource smelter maintenance.
KUC announced the permanent closure of the North Concentrator near Magna, Utah where operations were temporarily suspended in June 2001. On an annual basis, KUC's North Concentrator processed approximately 12 million tons of ore and produced about 60,000 tons of copper in concentrate. Because of the closure, concentrate sales, which had averaged about 100,000 tons per year in recent years, will cease. As a result of this closure, associated rail ore delivery systems at the mine will be shut down and the equipment fleet matched to the new mine plan. Two electric shovels and rotary drills together with part of the haul truck fleet will be idled. These changes will affect about 30 jobs. KUC anticipates that copper production for 2002, based on a lower ore grade at the mine, will be about 320,000 tons.
KUC will outsource the maintenance function at its smelter, affecting approximately 150 positions. The decision was arrived at only after the company and union failed to negotiate a reasonable, practical and mutually agreeable alternative. The implementation effects will now be discussed and negotiated with union officials. Eligible employees may be offered enhanced retirement benefits or other employment within the company, and there may be some forced reduction in numbers.
Bruce Farmer, KUC's President and CEO, said: "These are tough but necessary actions for our operations in response to the difficult economic climate. Copper prices remain at record lows and 50 per cent of American copper production is idled. We must reduce overall costs by 20 per cent and improve productivity significantly."
With an initial investment of $880 million in the mid 1990's, KUC built a new smelter and expanded and modernized its refinery. The smelter is the key facility that processes copper bearing minerals, through heat and oxidation in furnaces, into 99.5 per cent copper metal called anodes. The anodes are then transported by rail to the nearby refinery, where they are further processed into copper cathodes, which are sold to KUC's customers. KUC's smelter is the cleanest, most energy efficient copper smelter in the world. It captures 99.9 per cent of sulfur given off during the smelting process, and uses waste heat to co-generate about 60 per cent of the plant's electric power needs. On an annual basis, the smelter is designed to produce about 320,000 tons of copper anodes. (Rio Tinto news release, dated November 27, 2001)
December 2001
"Milling operations at the North (Bonneville/Magna) concentrator were suspended in June 2001 and it was permanently closed in December 2001, due to high operating costs and low copper prices." (David F. Briggs, Mining Operations Report, Bingham Canyon, June 2005)
December 2001
With the closure of the North Concentrator Complex at Magna at the end of 2001, Kennecott also ended its own rail operations. All rail operations in the Magna and Garfield area were out-sourced to a private contractor, using locomotives that Kennecott sold to the contractor. (Demolition of the Magna concentrator complex began in April 2007, with work starting on May 11, 2007 for the removal of the overhead flume and pipeline that carried tailings over State Route 201. -- Salt Lake Tribune May 11, 2007)
March 26, 2002
All rail switching operations were assumed under a contract awarded to Railworks. From that date, Railworks was responsible to deliver rail cars to Copperton, including cars with new conveyor belt segments for the conveyor belt refurbishment project. They also made several trips per month unrelated to the belt cars. On December 11, 2003, a separate contract line item was added for Rail Link to operate "extra switching" trains between Garfield and Magna, and Copperton. These became known as a "Copperton run."
As part of its contract with Kennecott, Railworks made a subcontract with Rail Link, a company owned by Genessee and Wyoming, the parent company of Utah Railway. Railworks was responsible for the operations contract and Rail Link furnished the operating crews. Railworks was also responsible for the maintenance of Kennecott's rail car fleet (mostly the white sulfuric acid tank cars). To fulfill the operations contract, Railworks purchased three of the GP39-2s from Kennecott. The Railworks contract (and Rail Link subcontract) remained in place until Railworks was purchased by Tangent Rail in 2005.
(Read more about railroad switching at Garfield)
August 2002
The longest of the six conveyor belts used to move ore from the pit to the Copperton mill was replaced due to normal wear and tear. It had been put into operation in January 1988, and was installed in the 5490 rail tunnel. The conveyor system consisted of six separate conveyor belts, with the longest, known as C-6, being 17,300 feet in length. By the time the longest belt was replaced, the conveyor system had carried 700 million tons of 10-inch minus material, from the in-pit crusher, out to the material storage pile adjacent to the Copperton mill. The conveyor belts were 72-inches wide. The C-6 belt was replaced during a normal 10-day downtime to move the in-pit crusher. "After almost 14 years of service, the most critical belt was removed after exceeding all warranty expectations. In particular, it exceeded warranty life by 40 percent and warranty tonnage by 245 percent. The belt was finally replaced [in August 2002] due to the convenience of system downtime created by a crusher move and because of the awareness of the increasing incidence of cord damage/breaks." (Dr. Robin B. Steven, The Goodyear Tire & Rubber Company, "Replacing C-6 Conveyor Belt at Kennecott Copper, Bingham Canyon Copper Mine")
"The first relocation was in 2002, and the crushing/conveying system was shutdown for 10 days. Prior to that the stockpile at Copperton was oversupplied by several hundred thousand tons to minimize production impact. Simultaneously with the shutdown the C6 (5490 tunnel conveyor) belt was changed - all 6 miles of it! During the shutdown the crusher control tower was raised and the dump pocket enlarged to accommodate 350 ton trucks - in 1988 our largest trucks were 240 tons. During this period the record daily throughout for the system was 205,000 tons, unless that's been exceeded it recent years."(Peter Harvey, Bingham Canyon History Facebook group, November 27, 2021)
The in-pit crusher and conveyor system was constructed in 1987 and went into service in early 1988. The in-pit crusher and conveyor system were moved in 2002 to accommodate pit expansion. The move in 2002 was the first time in 14 years the in-pit crusher had been moved. It was moved a second time in 2011, in a move that took nine days, with all the associated changes in the conveyor system that continued to use the 5490 tunnel. The in-pit crusher was moved a third and final time in 2020-2021. (Read more about the move in 2020-2021)
2004-2006
The following comes from Kennecott's 2004 Sustainable Development Report:
- East Wall Pushback - Work began in February 2005 to push back the east area within the open pit mine, to extend mine life through 2017.
- The current truck shop and visitors center will have to be moved in 2006 to accommodate the East Wall Pushback.
- Add a pebble crusher to the Copperton concentrator. Using pebble crushing will allow the concentrator to achieve higher throughput rates when encountering harder rock types in the mine, resulting in greater copper production.
- In 2005 and 2006, capital expenditures of $138 million will be spent on new and relocated mine facilities, mobile equipment and concentrator upgrades. Approximately $53 million in additional capital will be required in 2008 for the relocation of the in-pit crusher and de-watering facilities.
February 5, 2005
Kennecott announced a $170 million program to extend the life of the Bingham mine through 2017. The improvements include expansion of the Copperton concentrator, adding a fifth grinding line, and a major expansion of the open pit mine in what was called the East Wall Pushback. Both the truck shop and the visitors center would have to be moved to accommodate the East Wall Pushback. The price of copper was at 80 cents per pound, and was apparently stabilizing, compared to a high of $1.30 per pound in 2004. (Deseret News, February 5, 2005)
January 26, 2006
Kennecott spent $3.2 million in 2005 to reclaim waste rock piles and tailings ponds. The figure was far in excess of the $50,000 per year agreed to in 1978 as part of its on-going environmental cleanup efforts. The piles of waste rock were regraded to more natural contours, and soil amendments added to allow native grasses, shrubs and small trees to flourish, and to attract more native species of small animals, and the predators that depend on them, such as owls, foxes and coyotes. (Casper Star Tribune, January 26, 2006, citing an AP story)
March 11, 2006
The East Wall Pushback would move the east side of the Bingham open pit back 900 feet, would steepen the eastern wall, and would deepen the pit itself by 400 feet. Additional studies and test programs indicate that underground mining will provide a lower cost alternative to open-pit mining, providing easier access to the projected 17 million tons of copper, as well as 23 million ounces of gold and 190 million ounces of silver. Underground mining is completely different than open pit mining, and Kennecott will go slow as it develops the processes needed to safely and economically access the vast reserves that are apparently available by this new mining method, which would extend the depth being mined down several thousand feet, down to sea level. (Salt Lake Tribune, March 11, 2006)
June 30, 2006
Kennecott reopened the public visitor's center that overlooked the Bingham Canyon open-pit mine. The new 6,000 square-foot visitor's center was located 300 feet lower in the mine, and included "1,200 square feet of additional exhibit space and 12 new exhibits and displays, including four video locations. Visitors also may view a new 16-minute video in a 90-seat theater." (Salt Lake Tribune, June 24, 2006, Business Digest)
August 3, 2006
Kennecott announced that its Utah smelter would be shutdown for 45 days in September and October 2006 for scheduled maintenance. (Rio Tinto news released dated August 3, 2006)
2007
During 2007, Kennecott Utah Copper had the following production:
- Provides 17 percent of the nation's copper
- 300,000 tons of copper were produced
- 400,000 ounces of gold were produced
- 3 million ounces of silver were produced
- 24 million pounds of molybdenum were produced
- approximately 1 million pounds of sulfuric acid were produced as a by-product of the smelting process
- $2 billion has been spent to modernize the operations since Rio Tinto purchased Kennecott in 1989
- $350 million has been spent to cleanup historic mining waste sites, and $100 million has been spent in groundwater cleanup
- Kennecott has 1,600 full-time employees, and 600 contract employees
- (Kennecott news release dated October 22, 2007)
April 2007
Demolition started of the Magna concentrator complex, shut down since November 2001. The work, expected to be completed by June 2007, included the removal in May 2007 of the overhead pipeline from the mill to the tailings pond that crossed over State Route 201. The Arthur mill to the west, was shut down in 1984 and was demolished in 1991. (Salt Lake Tribune, May 10, 2007)
May 13, 2007
Magna Overhead Flume Removed -- Over the Mother's Day weekend, from Noon on Friday May 11th through early morning on Monday May 14, 2007, State Route 201 was closed to traffic while a Kennecott contractor removed the 200-foot high bridge and double pipeline that crossed over the highway between the Magna concentrator and the tailings pond to the north. The concentrator buildings were also being demolished as part of the project to remove all of the buildings of the concentrator that was closed in late 2001. The project was expected to last through the end of 2007. (Ksl.com, April 25, 2007)
Reclamation of the Magna concentrator site included removal of the concentrator and associated buildings, along with all below-grade foundations, and installation of storm water management and containment to stabilize the site. The project included placement of 15,500 cubic yards of fill material to contour the site, and planting 16 acres of grasses and shrubs. Instead of simply being buried on site, all of the concrete was removed and recycled as aggregate for use on new construction. The reclamation cost 4.6 million, and was finished in less than a year. (Utah Mining Association award, cited in the April 2010 issue of the UMA Newsletter)
2006-2008
The buildings and facility of the Bonneville crushing and grinding mill were demolished in 2006. Initial dismantling had begun in 2005, and the large crusher building and associated rail car dumper were demolished and were gone by early summer 2006. During 2008, the site was to be reclaimed and replanted to return it to its original state prior to the construction of the mill in 1966. (Sam Bass, email to the Utah Railroading Yahoo discussion group, March 12, 2007; Kirk Rogers, email to the Utah Railroading Yahoo discussion group, March 13, 2007; Kennecott Sustainability Report, 2007)
2006
"Several other historic facilities underwent demolition and reclamation during this year including a pumphouse, inactive portions of the Precipitation Plant, the Lead mine site and the Bonneville Crushing and Grinding facility." (Kennecott 2006 Sustainability Report)
2008
During 1995, Kennecott built a pilot plant to test the Solvent Extraction/Electrowining process. Located at Dry Fork, the pilot plant was closed in 1998. In 2008, a production Solvent Extraction/Electrowining plant was constructed at Copperton, and replaced the existing precipitation plant. (Utah Air Quality Control Board comment sheet dated August 4, 2008)
2008
Contractors completed the recovery of the North Ore Shoot. In 2007 Kennecott Utah Copper contracted with Atkinson Construction LLC of Golden, Colorado, to recover its North Ore Shoot vertical shaft that was built in the early 1980s but had since been capped, backfilled, and abandoned in the 1983-1984 period prior to the shut down in July 1984. In 2007, to uncover the old shaft, crews excavated a 230-foot-deep, 28-foot-diameter shaft through unconsolidated waste rock fill to an existing heavily reinforced concrete shaft collar. The recovery included a new headframe for the vertical shaft, which, as of June 2021, remains on the site near the 6190 truck shop.
(Read more about Kennecott's North Ore Shoot Extension)
September 2008
Kennecott announced that it move its headquarters from Magna to a new building at Daybreak, the planned community in Salt Lake County's southwest quadrant. Kennecott and Rio Tinto would consolidate all of their offices from throughout Salt Lake Valley into the single new location. About 570 people from Rio Tinto, Kennecott Utah Copper, and Kennecott Land would be part of the move, which was expected to be completed by the end of October. Kennecott Utah Copper had been located in Magna for about 10 years, and before that, in downtown Salt Lake City in what was known as the Kennecott Building on the southeast corner of Main Street and South Temple Street. The new building at Daybreak had about 137,000 square feet and is part of the Daybreak Corporate Center. (Salt Lake Tribune, September 2, 2008)
November 8, 2008
Kennecott announced that they would build a molybdenum smelter at Magna, with ground breaking set for Tuesday November 11, 2008. Kennecott said the $270 million Molybdenum Autoclave Processing facility will run on clean energy and reduced emissions. Tom Albanese, chief executive of Kennecott parent company Rio Tinto, said that China and India are big buyers of molybdenum, a silvery white metal with many applications, including the points on spark plugs that fire everyday engines. The news release stated that molybdenum is a byproduct of copper production, and is used in high-strength steel alloys. It's also a key ingredient in oil refining. (KSL.com, November 8, 2008)
Prior to building the molybdenum facility, Kennecott sent semi-processed molybdenum to refineries in Belgium and Mexico for processing into finished metal. This new facility would allow Kennecott to process its molybdenum ore into finished and marketable metal. Molybdenum is used is steel making to make steel stronger, and to remove sulfur from crude oil as part of the refining process. Kennecott currently produces 300 million pounds of molybdenum per year, but is of a lower quality. Producing a higher quality molybdenum will increase Kennecott's share of the worldwide market for 400 million pounds per year. (Deseret News, June 11, 2008)
2008 Bingham Daily Production:
- 450,000 tons of waste rock and ore is hauled every day, of which 99 percent is waste rock
- 795 tons of copper is produced each day
- 12,000 troy ounces of silver
- 1,400 ounces of gold
- 20 tons of ore is mined to produce an 18-carat gold wedding ring
- (Fortune magazine, cited in CNNMoney.com, September 3, 2008)
2008
The following comes from Rio Tinto's 2008 annual report:
A US$82 million expansion and modernization of the bulk flotation process at KUC's Copperton concentrator was completed during 2008. The project is expected to increase copper recovery by two per cent and concentrate grade by four per cent.
A US$73 million investment in mining equipment has also been agreed in order to accelerate mining and allow possible mine extensions beyond 2019.
Kennecott Utah Copper -- (Rio Tinto: 100 per cent) -- KUC operates the Bingham Canyon mine, Copperton concentrator and Garfield smelter and refinery complex near Salt Lake City, Utah. KUC is a poly-metallic mine, producing copper, gold, molybdenum and silver. As the second largest copper producer in the US based on 2008 production, KUC supplied approximately 12 per cent of the US's annual refined copper requirements and employed approximately 1,900 people at 31 December 2008.
Ore processed at the Copperton concentrator in 2008 was a new record. KUC's copper in concentrate production increased to 238,000 tonnes in 2008, an increase of 12 per cent from 2007. Copper cathode production of 200,600 tonnes was 65,000 tonnes less than in 2007. The decrease in refined copper and gold were primarily the result of a planned smelter shutdown during the second half of 2008. Molybdenum concentrate production in 2008 was 19,400 tonnes, compared to 26,600 tonnes in the previous year. The decrease in molybdenum production was driven by a nearly 17 per cent decrease in ore grades compared to 2007.
Stripping of waste rock on the east side of the pit was accelerated in mid 2008. This is expected to bring deliveries of higher grade ore forward to compensate for declines in ore grades expected in 2011 and 2012. Current ore reserves and mineral resources are expected to enable open pit operations to continue until 2019 and possibly to 2036.
2008 Kennecott Production:
- 13 percent of the nation's copper
- 292,280 tons of refined copper, compared to 240,200 tons for 2007
- 523,000 ounces of gold
- 4,364,700 ounces of silver
- (Deseret News, February 14, 2008)
2009
During 2009, Rio Tinto's Bingham Canyon mine was the number two copper mine in the nation (first was the Morenci mine in Arizona), and the United States was second on the world's copper producing nation in the world (first was Chile). (CopperInvestingNews.com - Top 10 Copper Producing Countries)
2009 Kennecott Production:
- Bingham mine provided about 18 percent of United States copper production
- Copper - 334,600 metric tonnes
- Gold - 584,000 ounces
- Silver - 4,877,000 ounces
- Molybdenum - 24.9 million pounds
- Sulphuric Acid - 1,071,000 tons (byproduct of smelting process)
- (Source: Rio Tinto, Kennecott Utah Copper Facts, dated February 2010)
Worldwide 2009 Copper Production
- Chile was the largest copper producer worldwide, producing 5,320,000 metric tonnes in 2009
- The Minera mine in Chile is the largest copper mine in the world (started development in 1990; production started in December 1999; first full year production was in 2000); produced 1,255,000 metric tonnes in 2008
- United States is the second largest copper producer, producing 1,310,000 metric tonnes in 2009
- The Morenci mine in Arizona is the largest copper producer in the U.S., producing 380,000 metric tonnes per year
- The Bingham Canyon mine in Utah is the second largest copper producer in the U. S., producing 265,000 metric tonnes in 2006
- (Source: CopperInvestingNews.com)
In July 2010, Kennecott upgraded the Copperton Concentrator. "Kennecott Utah Copper LLC (KUC) has requested approval for installation and operation of a pilot hydraulic roll press and associated equipment at the KUC Copperton Concentrator plant. Existing operations at the Copperton Concentrator are permitted under Approval Order (AO) DAQE-AN0571019-06. KUC is proposing to operate a new high pressure grinding roll press with different roll surface technologies for material size reduction. The equipment will consist of a coarse ore feed hopper, cone crusher and screen unit, hydraulic roll press and conveyor belts. Ore will be taken from the existing Copperton Concentrator coarse ore stockpile and fed into the cone crusher. The product from the cone crusher and screen unit will then be fed to the hydraulic roll press through a conveyor system. The final crushed ore product will be returned to the Copperton Concentrator coarse ore stockpile and then fed through the existing Copperton semi-autogenous grinding mill. Dust suppression water spays will be used on the partially enclosed cone crusher and screen unit. Dust control for the hydraulic roll press will be provided by a baghouse"
In August 2010, Kennecott Utah Copper began the approval process to expand the size of the Bingham Canyon mine, and to increase overall production. The expansion is known as the Cornerstone Project, and will pushback the south and southeastern walls of the Bingham open-pit mine, and deepen the pit by 300 feet to gain access to 700 million tons of ore. The project itself includes expansion of the mine, the Copperton concentrator, the power plant, and the tailings pond. The approval and permitting process was expected to take until late 2012 or early 2013. (Kennecott news release dated August 16, 2010)
In December 2010, Rio Tinto proposed to replace three coal-fired boilers at its Magna power plant, with a single natural gas-fired turbine and generator. The largest coal-fired boiler (Unit 4) will remain in use to give the power plant an alternate source of fuel. Unit number 4 was completed in 1959 and has always had the capability to be fired by either natural gas, or by coal. The improved power plant is needed to provide additional power to the planned Cornerstone project at the Bingham mine.
(Read more about Kennecott's Central Power Station)
In 2010:
- Nearly 25 percent of U.S. copper production
- One of the top producing copper mines in the world with total production at more than 19 million tons
- Produced approximately 296,000 tons of copper, 596,000 ounces of gold, 4.7 million ounces of silver, 28 million pounds of molybdenum
- Rio Tinto purchased the Bingham Canyon Mine and related facilities in 1989 and has invested more than $2 billion in the modernization since then
- Kennecott Utah Copper has also spent more than $350 million on the cleanup of historic mining waste and $100 million on groundwater cleanup
- Rio Tinto employs 2,400 people and influences 14,800 indirect Utah jobs and spends $1 billion in the state of Utah in wages, benefits, taxes and purchases from nearly 1,000 Utah area businesses every year
- (Kennecott Utah Copper news release, October 19, 2011)
2010 Kennecott Production:
- Production decline to 250,000 tons, compared to 303,500 tons in 2009, but still the leading U.S. copper mine producer
- Average copper grades declined to 0.53 percent, from 0.64 percent in 2009
- Molybdenum production increased to 12,900 tons from 11,300 tons in 2009
- Production of refined copper decreased to 269,000 tons from 274,000 tons in 2009
- (USGS 2010 Minerals Handbook, Copper)
August 2011
As part of the Cornerstone project, a fifth grinding line was added to the Copperton Concentrator. "Addition of an Ore Grinding Line and an Ore Sorting Plant. Kennecott's plans to install and operate a fifth ore grinding line and an ore sorting plant at the Copperton Concentrator. The new equipment will consist of an ore sorting plant with a baghouse, a small natural gas fired heater, a cold solvent degreaser, a fuel oil tank, a conveyor belt with transfer points, a pebble crusher, two lime bins with bin vents and a cooling tower to support the fifth ore grinding line."
Process Overview
Ore from the Bingham Canyon Mine is stockpiled in a storage pile in an A-frame enclosure. The process works like this:
-- From the storage pile, the ore is fed to the grinding lines through the coarse ore reclaim tunnels and a series of conveyors directly into the semiautogenous grinding (SAG) mills.
-- The SAG mill is equipped with a trommel screen allowing minus 5/8-inch material in slurry to pass through for further processing while discharging the larger pebbles at the trommel exit, where they are conveyed to the enclosed pebble crushing building and further reduced.
-- The slurry is sent to the cyclone clusters, where the overflow (30 percent solids) is sent to the flotation circuit for concentrating and the underflow (70 percent solids) is sent to the ball mills for further size reduction before being sent back to the cyclones and on to the flotation circuit. Inherent moisture content of the material in the SAG mill, ball mill, and cyclone processes eliminate emissions.
-- A cooling tower is used to cool the motors used in the grinding circuit. Drift eliminators installed on the cooling tower will eliminate drift to 0.005 percent of the process water flow.
-- Cyclone overflow is fed into the flotation circuits, mixed with reagents, and aerated to float copper and other valuable by-products from the ore. Concentrate overflow is pumped to the existing regrinding circuit, while tailings underflow gravity flows to a collection trench. Because the rougher scavenger flotation process is aqueous based, no emissions are emitted from the flotation circuit.
-- Tailings underflow from the flotation circuits feeds from the collection trenches to the tailings thickener feed distributor. Tailings are transported by gravity flow to the tailings impoundment for final deposition via pipelines. Thickener overflow is pumped back to the process water reservoir. No air emissions are emitted from the tailings thickening operations.
September 2011
North Ore Shoot gold and copper skarn was the underground expansion project for Kennecott Utah Copper, one of the largest and oldest copper mines in the world, and a flagship mine for Rio Tinto. The ore body is about 1000 feet below the current bottom of the Bingham open pit mine, and the North Rim Skarn project will involve the construction of an underground mining facilities, including new vertical shafts and horizontal drifts and galleries and declines, as well as refurbishing an existing shaft. Most of the work will be contracted out. (Rio Tinto news release dated September 20, 2011)
A "skarn" is the area between host waste rock and mineralized ore rock, and can usually be mined due to high concentrations of minerals.
The new vertical shaft was to be connected to the existing vertical exploration shaft from the 1980-1981 period. The newer headframe and hoist were in the same location on the 6190 level as the previous headframe and hoist that had been removed to allow nearby waste-rock dumps to be expanded. The headframe was re-installed in about 2008 and was about 230 higher, on the same vertical shaft.
The new vertical shaft, 28 feet in diameter and 240 feet high, connected with the existing shaft, 20 feet in diameter, previously completed to a depth of 3,089 feet in 1983. The copper and gold deposit was further explored in the early 1980s with 12,300 feet of horizontal tunnels, known as "drifts," along with continuing to drill exploration holes. In the mid 1980s the vertical shaft accessing the North Ore Shoot, along with the former Anaconda Carr Fork mine (sold to Kennecott in 1985), were allowed to flood, and the shaft was sealed at the top and the headframe was removed. In 2007 the vertical shaft had been recovered after burying it with 230 feet of waste rock, and a new headframe was installed in 2008.
In 2011:
- On average, each person in America uses about 30 pounds of copper every year.
- A typical new home contains about 500 pounds of copper -- found mostly in wiring, plumbing and brass fixtures.
- Kennecott produces nearly 25 percent of the copper produced in America. Gold and silver are byproducts of the mining process.
- The largest electric shovel has a 56-cubic-yard dipper that scoops up approximately 98 tons of material in a single bite, a weight equivalent to about 50 automobiles.
- There are about 80 gigantic haul trucks operating in the mine. These trucks carry as much as 320 tons of material in a single trip.
- The fleet of haul trucks travel more than 10,000 miles a day at an average speed of 13 miles per hour.
- The elevation of the Bingham Canyon Mine drops from 8,040 feet above sea level to 4,390 feet above sea level.
- (Source: Rio Tinto)
2011 Kennecott Production:
- Second largest copper producer in the United States
- Nearly 25 percent of U.S. copper production
- Produced 237,300 tons of copper
- 379,400 ounces of gold
- 3.2 million ounces of silver
- 30 million pounds of molybdenum
- 878,300 tons of sulfuric acid
- Rio Tinto employs 2,810 people, influences 15,000 indirect Utah jobs and annually spends about $1 billion in the state of Utah in wages, benefits, taxes and purchases from nearly 1,000 Utah area businesses.
- (Source: Rio Tinto)
March 2012
Rio Tinto announced a test in 2013 for the use of a tunnel boring machine to develop underground mining methods at Kennecott's Bingham copper mine. The following comes from Mining Magazine, April 2012 (dated March 29, 2012)
Rio Tinto has announced a second tunnel-boring trial, aimed at significantly reducing the time taken to excavate underground.
The company is working in partnership with Atlas Copco on the trial, which will start in 2013 at Rio Tinto's Kennecott Utah Copper (KUC) mine in Salt Lake City. Tunneling rates of 10 meters per day are expected; nearly twice that of conventional methods.
Later this year, the Copper NuWave recovery technology, will be trial tested at Kennecott.
The first tunnel-boring trial is set to start this year, in partnership with Aker Wirth at the Northparkes copper and gold mine in New South Wales. Locations are currently being considered for a shaft-boring system trial.
John McGagh, head of innovation at Rio Tinto, pointed out that mining is moving increasingly towards underground operations as deeper ore bodies are being identified and open pits reach the end of their life.
He added: "These trials mean we can test the technology to allow us to mine deeper and more safely, with the potential benefits of greater efficiency and speed of underground mine construction, which would increase the value of projects."
As part of the mineral-recovery program, the company has even looked outside the mining industry by partnering Norway's TOMRA Sorting Solutions, which supplies sensor-based systems used in recycling and food processing. Together, the companies plan to develop commercial-scale systems for separating minerals from rock waste.
Another partnership with UK-based e2V uses large-scale microwave technology and radio-frequency generators to improve the efficiency of mineral recovery from discarded ore.
Mr McGagh added: "This technology has the capability of being a potential game changer in the mining industry."
June 2012
Rio Tinto announced that it would invest $660 million in its Kennecott Utah Copper mine at Bingham canyon. The investment would extend the life of the mine by 11 years, through 2029, and would include further development of processes to pursue ongoing underground mining operations, along with additional infrastructure to continue the Cornerstone Project, which will push back the south wall of the current open pit mine by 1000 feet, and deepen the mine by 300 feet. The project is focused on removing waste rock to allow access to additional 700 million tons of ore reserves, with actual mining of ore not expected until 2017. (Rio Tinto news release dated June 19, 2012; Salt Lake Tribune, June 29, 2012)
2012 Kennecott Production
- Mine production was 163,200 metric tonnes in financial year 2012, down 16 percent from financial year 2011.
2013
"The KUC Bingham Canyon Mine produced most of the copper in Utah and remained the second leading copper producer in the United States There was a temporary halt to operations after a pit wall failure in 2013. In June 2012, the $660 million Cornerstone push-back was approved to extend the Bingham Canyon Mine life from 2018 to 2029. This project involves pushing back the south pit wall about 300 meters to access an additional 515 Mt of ore." (USGS, Mineral Industry in Utah, 2012-2013, page 47.2)
April 10, 2013
Kennecott Utah Copper's Bingham Canyon Mine experienced a slide along a known fault line of its north eastern wall at 9:30 pm local time on April 10. An examination of available photographs shows that the site of the visitor's center was completely taken away by the slide, along with a large portion of the Apex truck shop. Movement on the north eastern wall had accelerated in recent weeks and pre-emptive measures were taken to relocate facilities and roads before the slide. All employees were safe and accounted for.
Notable is Kennecott's preparation for the slide, including moving the portion of the conveyor belt in the former railroad 5490 tunnel, which moved ore from the mine out to the Copperton mill. Although the scale of the slide was massive, and the amount of material that slipped from the top down to the bottom of the pit was equally massive, Rio Tinto was completely capable of solving this problem, and production l resumed as soon as safely possible.
(View Kennecott Utah Copper's photos of the slide on Flickr)
(Read the Deseret News article from April 11, 2013)
Just days before, geologists had measured movement of one-half inch per day. In anticipation of the work needed after the slide, Rio Tinto moved equipment to the bottom of the pit, on the far side of where the slide was projected to end. Included were several "new" drills because planners assumed that the slide would block of access to the pit bottom and wanted new equipment that would require less maintenance on the far side to maintain production while the access road was dug out. The slide was much larger than anticipated and buried a lot of equipment as well as stockpiles of fuel, tires and parts. The slide was larger than expected and buried nine haul trucks and three shovels that had been prepositioned, as well as a lot of other equipment and tools.
April 15, 2013
"Kennecott unit produces about 17% of copper supplies in the U.S. In 2012, output was close to 163,000 tons of refined copper plus 279,000 ounces of gold and about 9,400 tons of molybdenum, used as an alloy in steel. Rio Tinto last June approved spending of US$660 million to extend the life of the Bingham Canyon mine to 2029 from 2018. Commonwealth Bank said Monday that assuming the Bingham Canyon mine isn't operational for the rest of the year, the mine likely would report a loss of US$79 million. The bank had previously expected the mine to earn US$701 million this year, about 6% of Rio Tinto's total earnings." "The slip has destroyed the main access [tunnel] into the pit, so a new [tunnel] will need to be constructed before mining can resume." (Dow Jones Business News, April 15, 2013)
April 16, 2013
"On 10 April 2013, the Kennecott Utah Copper mine experienced a slide along a geotechnical fault line of its north eastern wall. Waste movement associated with the Cornerstone extension has restarted but ore production remains suspended and timing to restart ore production remains under evaluation. The concentrator has been shut down while the smelter and refinery are currently operating at reduced levels. Based on an early assessment of information currently available, it is estimated that 2013 refined copper production at Kennecott Utah Copper will be approximately 100,000 tonnes less than previously anticipated." (Rio Tinto, First Quarter 2013 Review)
"Rio Tinto said the collapse of a large section of the pit wall at the Bingham Canyon mine in Utah last week will mean its production of refined copper could fall by about 27% this year, making the company even more reliant on iron ore prices to drive its earnings. Ground near a section of the pit had been unstable for months and finally slumped into the mine last Wednesday, carrying with it more than 150 million metric tons of material and damaging 14 haulage trucks and other equipment. Rio Tinto had moved buildings and equipment in anticipation of a slide, but the effect on production would still be significant." (Fox Business News, April 16, 2013)
The slide damaged three of the mine's 13 shovels, and 14 of the mine's 100 hauling trucks. The equipment had been positioned at the bottom of the mine, away from what was expected to be the extent of the slide. But the slide material progressed farther than the planners thought it would.
"Rio said earlier on Tuesday it expects Kennecott's 2013 copper production to be reduced by about 100,000 tonnes because of the slide. Kennecott is the second-largest copper producer in the United States. Bingham Canyon, one of the world's largest open pits, produced 163,200 tonnes of copper last year, as well as 200,000 ounces of gold." (Reuters, April 16, 2013)
"Originally the miner had expected to produce 300,000 tonnes from Bingham Canyon this year but the landslip has turned out to be more extensive than first thought. Ironically the shortfall on copper production could, according to some analysts, be enough to hold up the world copper price because the supply and demand for the metal is so closely balanced. Copper prices have fallen this year over fears that China's economic growth is slowing." (London Times, April 16, 2013)
Rio Tinto has other copper mines in Chile (Minera Escondida), Indonesia (Grasberg), Australia (Northparkes), and South Africa (Palabora), with mines in final development in Peru (La Granja) and in Mongolia (Oyu Tolgoi), as well as a joint venture with BHP at Superior, Arizona (Resolution Copper project).
(Read the Wikipedia article about Rio Tinto's copper mines)
April 26, 2013
Rio Tinto to resume loading at Utah copper mine:
London, April 26, 2013 (Reuters) -- Rio Tinto's Kennecott Utah Copper expects to begin transporting copper ore to the concentrator at its Bingham Canyon mine in the next few days, after a landslide forced it to stop operations.
A spokesman for the company said crushers, tunnels and the conveyor system had now been checked and were found to be unaffected by the landslide earlier this month.
'We anticipate being able to start transporting ore to the concentrator in the next few days. Clearly it will be at significantly reduced volumes,' he said on Friday.
Rio had been forced to invoke force majeure with respect to contracts with copper cathode and sulphuric acid customers, and the company said that remained in place.
Rio said at the time of its first-quarter production statement that it expects Kennecott's 2013 copper production to be reduced by about 100,000 tonnes because of the slide.
Kennecott is the second-largest copper producer in the United States. Bingham Canyon, one of the world's largest open pits, produced 163,200 tonnes of copper last year, as well as 200,000 ounces of gold. (Reporting by Clara Ferreira-Marques; Editing by Alison Birrane)
(This crusher and conveyor system has been in place since January 1988, and uses the former 5490 railroad tunnel, itself completed in February 1959. The tunnel portal in the mine had been closed in anticipation of the slide, and the portion of the conveyor system potentially in harm's way had been safely removed.)
April 26, 2013
Rio Tinto To Restart Conveyor Belt At Utah Copper Mine
London April 26, 2013 (Dow Jones News) -- Rio Tinto PLC's Kennecott Utah Copper expects to start transporting copper ore to the crusher at its Bingham mine within the next few days following a mudslide that led to the shutdown its operations there, a company spokesman said Friday.
The spokesman said that the ore transportation system, which includes a conveyor belt that takes copper ore through a tunnel to a crusher was unaffected by a landslide at its Bingham mine in Utah, US earlier this month.
"We expect to start the transport of ore on the belt conveyor in the next few days," a company spokesman said. He however noted that it would still be a while before operations return to normal and added that a force majeure on customer contracts related to copper cathode and sulphuric acid sales was still in place.
Rio Tinto said during its first-quarter results that it expects to produce 100,000 metric tons less of refined copper this year due to the April 10 landslide.
The spokesman said the company "anticipates being able to access all parts of the pit in the next few weeks."
Kennecott Utah Copper is the second-largest copper producer in the U.S., accounting for nearly 25% of annual U.S. copper output. In 2011, Kennecott produced 237,000 tons of copper, 379,000 troy ounces of gold, 3.2 million troy ounces of silver, 30 million pounds of molybdenum and other products. (Reported by Alex MacDonald)
April 27, 2013
Rio Tinto restarted its conveyor delivery of ore on April 27th, but warned that due to the landslide, it would lose 150,000 tons of mined output (92 percent of previous year), and 100,000 tons of metal
production (61 percent of previous year). (Reuters UK, May 14, 2013)
June 2013
Due to reduced production at the Bingham mine following the slide in April, Rio Tinto began receiving third-party concentrate at its Kennecott Utah Copper smelter. The first shipment was a total of 30,000 dry metric tonnes of copper concentrate from the Robinson, Nevada, mine operated by KGHM. The shipments were part of a total of 150,000 dry metric tonnes that Kennecott was forced to buy from third-party sources during June through October 2013, when the Bingham mine began providing sufficient quantities of concentrates to match the capacity of the Garfield smelter. (Reuters, May 22, 2013)
October 2013
From the Rio Tinto 2013 Third Quarter report: "2013 expectations for mined copper at Kennecott Utah Copper have been upgraded to 185,000 tonnes. The new heavy vehicle access road is expected to be operational in the next few weeks."
(View a two-minute YouTube time-lapse video of repairs to the access road.)
December 2013
Kennecott Utah Copper completed its expanded Copperfield truck shop, located north of the older "6190" shop that was being closed to accommodate expansion of the open pit. The older 6190 shop was essentially empty at the time of the land slide on April 11, 2013, which swept away a portion of the 6190 shop.
The following comes from Utah Construction & Design magazine:
This project consists of a 116,000 square feet expansion on each side of Kennecott Utah Copper’s existing Copperfield Truck Shop. The addition included 16 new offices, 12 service and repair bays, two tire service bays, four new overhead cranes, a storage building and a separate change-house facility. The expansion also includes a new warehouse area to store and supply the expanded shop with parts.
The truck shop expansion was designed to accommodate huge mining equipment currently in use, including the massive 400-ton CAT 797F truck, which is more than 25 feet tall.
Amenities include an updated lube system, a fire suppression system, and a new hydronic in-floor heating system, which provides continuous warmth to shop employees and eliminates ice buildup on the concrete approach during winter months. Large fabric door are able to absorb minor collisions and can be repaired quickly. (Utah Construction & Design magazine, December 1, 2013)
The following comes from the Big D company's web site:
When the Kennecott Copper Mine doubled the number of 300-ton dump trucks in its fleet in 2006, the company needed more space to maintain them. Big-D built a new truck maintenance shop to meet the new demands on Kennecott’s existing truck shop. Big-D Construction performed the concrete work and steel erection of the new shop for Kennecott. The concrete footings are 16 feet square and eight feet deep; large enough to support the massive 300-ton dump trucks when they are fully loaded. The footings also support the hydraulic jack used in repairs.
The Kennecott Truck Shop project included a large truck maintenance area, complete with tire storage, office space, and supplemental storage tanks to house the necessary fluids for the vehicles. In addition to the large truck facilities, Big-D built a small truck wash bay and pump house, including adjacent water clarification ponds.
39,000 square feet; completed in five months.
2020-2021
The Bingham Conveyor System was moved from its in-pit location near the 5490 tunnel to allow expansion along the pit's east side. The former 5490 railroad tunnel was retired at the same time.
In March 2022, the railroad overpass crossing of State Route 111 (Bacchus Highway) at about 7500 South in southwestern Salt Lake Valley was removed by a contractor working for Utah Department of Transportation. The same contractor, at the same time, removed the overpass crossing at 5400 South. The Kennecott Ore Haulage railroad (a private railroad) that crossed S.R. 111 and 5400 South at those points had not been used for 20 years.
###