The Bingham Mine - Our National Historic Landmark

Bingham Canyon Mine is the largest open pit mine in the world. It measures over 0.75 miles deep (1,210 meters) and 2.5 miles (4 kilometers) wide (NASA 2007). In 1972, Bingham Canyon Open Pit Copper Mine was designated a National Historic Landmark (NHL) through the National Park Service’s NHL Program, which designates sites based on their significance to the history of the United States (U.S.). At the time of its NHL designation, the Bingham Canyon Mine Visitor Center saw 370,000 visitors a year. Often called “the richest hole on earth,” Bingham Canyon Mine produced 159,400 tons of copper, 139,500 ounces of gold, and 2.22 million ounces of silver in 2021 (Mining Technology 2022). Bingham Canyon gained its national fame as an important site not only due to its enormous size, but also because the mine was the first in the world to implement large-scale open pit mining and an economical method of processing low-grade copper ores (Krahulec 2007). 

Photograph 1: Bingham Canyon Mine n.d. Courtesy Rito Tinto Kennecott Copper (RTKC)

Several metals have been historically mined out of Bingham Canyon. Lead-silver was discovered in 1848 in Bingham Canyon when two brothers were sent to settle the Oquirrh Mountains along the west side of the Salt Lake Valley for ranching purposes. Thomas and Sanford Bingham, the canyon’s namesakes, reported the ore’s presence in the canyon to Brigham Young, then the leader of the Church of Jesus Christ of Latter-Day Saints. Not wanting to create an influx of non-Latter-Day Saint miners, Young decided to not pursue mining in the region (Arrington and Hansen 1963). 

Silver-lead ore was found by Army troops under the command of Colonel Patrick E. Connor, who assayed it. Once discovering its value, Connor directed the formation of the “West Mountain Mining District” in December 1863 covering Bingham Canyon and much of the Oquirrhs (Krahulec 1997). Connor’s goal was to bring in a rush of miners and prospectors to “overwhelm the Mormons by mere force of numbers…without the loss of a single soldier in conflict” (Arrington and Hansen 1963:12). 

In 1860, copper was found near Bingham Canyon. At the time, however, prospectors and miners did not see value in mining for copper. As the Deseret News reported on the find, they commented that “…in these days, gold is the principal thing sought after, and a man who would engage in copper mining in an inland coun’ry (sic) like this, might by some, be considered in a state of insanity” (Deseret News May 9, 1860). It would take three decades before interest and investors sought the valuable copper in Bingham Canyon.

Enos A. Wall, a miner and prospector, saw the potential of copper mining in Bingham Canyon, although many at the time scoffed at the idea of profiting from the ore, calling the copper “Wall’s rock” (Arrington and Hansen 1963:16). While investors and miners were still not convinced that low-grade copper ore could yield a sizable profit, Wall disagreed. After assaying copper in Bingham in 1887, he immediately staked claims in the area. To gain financial backing for his copper mining interests, Wall turned to Robert C. Gemmell and Daniel C. Jackling to take samples and test the ore. The two determined that processing the ore in large quantities would prove to be profitable. The 1899 Jackling-Gemmel report discussed stripping the overburden from the ore and utilizing railroad cars and steam shovels to haul both from the mine (Arrington and Hansen 1963:33). By 1900, Wall had acquired most of the claims in the canyon, covering nearly 200 acres, and in 1903, he established the Utah Copper Company (UCC).

Open pit mining didn’t come into practice at Bingham Mine until 1909. Prior to that, mining copper occurred through a system of mining called “caving.” Caving occurs below ground where sublevels are mined, causing the ore to collapse or slough off (Mindat.org 2022). This caving system of mining was in practice at Bingham Mine until 1907 (Arrington and Hansen 1963:31–33, 52). 

As mining operations continued to expand in the Bingham Canyon area, the need for cheap labor also increased. Workers soon flooded into the area from all over the world. By 1912, around 65 percent of residents living in Bingham Canyon were foreign immigrants and by the early 1920s, the canyon’s population had grown to more than 15,000 (Crump 1994:43). Immigrant workers tended to settle together in camps with their fellow countrymen across different parts of the canyon. British, Welsh, Cornish, and Irish workers settled at Lark and Bingham; Finns, Swedes, and Norwegians at Carr Fork; Eastern and Southern European Slavs and Italians at Highland Boy; Greeks at Copperfield; Japanese at “Japtown”; and French-born miners at “Frogtown” (Crump 1994:43; Notarianni 1990:20). 

Photograph 2: Highland Boy, Bingham Canyon, n.d. Courtesy RTKC

The entry of the U.S. into World War I had a significant impact on copper mining operations in Bingham Canyon. Although the nation was generally supportive of the U.S. war effort, tensions arose between Euro-Americans and various ethnic groups not aligned with the U.S. The war effort also created a demand for metal and initiated major increases in productivity at all Utah mines and smelters (Sillitoe 1996:146). The UCC was a beneficiary of this increased demand and production increased from 63,798,500 short tons of ore (at a value of $16,204,800) in 1910 to 143,337,100 short tons (at a value of $67,342,000) by 1917 (Notarianni 1990:24). 

While production was increasing during the early 1900s, working and living conditions in the canyon and surrounding area were increasingly strained. At Bingham, the steep topography of Bingham Canyon meant that there was room for only one winding main street along the seven miles of canyon. The narrowness of the canyon was a safety hazard and contributed to floods, fires, and avalanches, all of which made it difficult to establish safe housing (Crump 1994:43). These dangerous conditions led UCC employees to petition the company for additional housing. The UCC, recognizing the importance of keeping their employees close to UCC operations, agreed to build new housing on a rise north of Bingham Creek. This area was known as “Rattlesnake Flats” because of its desolate appearance, although the soon-to-be community was officially named Copperton in honor of the original Copperton Mill (Crump 1978:12).

Photograph 3: Bingham Canyon and Railroad Operations 1923. Courtesy Utah State Archives.

After the end of World War I, mining returned to pre-war levels while towns in the Bingham Canyon continued to grow. The beginning of the Great Depression in 1929, however, brought that prosperity to an end. The Depression hit Utah hard and by 1932, the state had the fourth highest unemployment rate—36 percent—in the country. By 1935, one out of five—or 20 percent—of Salt Lake County families were receiving financial aid of some sort, while many others lived in abject poverty (Sillitoe 1996:173). 

Conditions for mine workers, however, were less severe. For example, the UCC, though experiencing a severe decline in production due to a low demand for copper, did not conduct massive layoffs (as most other local companies did). Instead—and much to their credit—officials at the UCC divided the remaining work among the employees. Initially, each employee worked 15 days straight and then had 15 days off. As the Depression worsened, though, this schedule was reduced to 10 days on and 10 days off. The UCC also charged its employees for rent only on days that the employee worked, provided fuel, allowed employees to pay for necessities only when they had money, and generally ensured that employees had food (Crump 1978:23–24). Due to these provisions and policies, most of the Bingham Mine area’s mining operations weathered the storm of the Great Depression and emerged intact. Also, of note during this period, Kennecott Copper Corporation (KCC), previously a minority stockholder in the UCC, purchased UCC in 1936. Following this purchase, operations at the local mining properties continued to expand under the new ownership. 

Utah as a whole and Bingham Canyon mining operations—much like other industries across the country—did not recover from the Great Depression until the beginning of World War II. The new war caused an increased demand for metals, as well as for agricultural and other commodities, and rapidly pulled the country out of the Great Depression. By 1943, ore production at Bingham Mine had skyrocketed to 323,989,000 tons per annum (valued at $84,237,100) (Notarianni 1990:24–25) and work was plentiful for area miners and mill workers. Because of high levels of demand, and because many male workers were now in the military, local teenagers and women often went to work at area mines to fill in the gaps. 

Wartime production set new world records for copper mining at Bingham Mine— including the production of 30 percent of the copper used during World War II—and pushed KCC into the national consciousness (Cononelos and Notarianni 1994:300; Crump 1978:37). On January 25, 1945, the U. S. Army took over the operation of the Bingham and Garfield Railway (B&GR) due to a labor dispute. The subsequent strike and shutdown of the railroad resulted in President Roosevelt authorizing the government takeover. The takeover was deemed necessary due the critical role of KCC in copper production for the war effort.  Control of the railroad returned to the company in September 1945 following the end of the war (Strack 2022). 

The B&GR received its first diesel-electric locomotive in 1942. The construction of a new, 14-miles long electrified railroad from Copperton to Magna began in 1946. In 1948, the new Copperton Low Line (CLL) began operations; that same year, the B&GR ceased operations and was later dissolved. The reason for the abandonment of the B&GR was that the CLL was constructed at a lower gradient than the B&GR, thus allowing for longer trains and increased ore hauling capacity. New high voltage locomotives were purchased for the CLL and the dumper yards at Magna and Arthur were converted to accommodate the higher voltages (Strack 2022).

Photograph 4: Bingham Canyon Mine 1957. Courtesy Utah State Archvies

In 1966, the National Survey of Historic Sites and Buildings nominated Bingham Canyon Open Pit Copper Mine as a National Historic Landmark (NHL), but KCC leaders refused to sign the document at the time because it was not seen as being beneficial to mine operations. Following this initial refusal, however, KCC leaders recognized that the visitor center brought in 370,000 visitors a year, thus illustrating the public relations value of the site (Lissandrello 1975). Therefore, when the National Park Service returned in 1972 to verify the earlier designation, KCC retracted its original decision and signed the documentation making the site an NHL. In 1984, Bingham Canyon Open Pit Copper Mine was also listed on the National Register of Historic Places (NRHP), further preserving, and reinforcing the status of the property as an NHL. 

KCC was bought by Rio Tinto Zinc in 1989 and was rebranded as Rio Tinto Kennecott Corporation (RTKC). Operations continued under new ownership with production levels rising above 250,000 short tons of copper produced yearly between 1990 and 2000. The Bingham Canyon Mine experienced two of the largest mining-related landslides in mining history on April 10, 2013. Named the Manefay Slides by RTKC, the landslides carried 145 million tons of waste rock into the pit. The first landslide—carrying 100 million tons of material— occurred at 9:30 p.m. and was followed by a smaller landslide. Eleven minutes after the second landslide, a magnitude 2.5 earthquake occurred beneath the mine. Despite all this activity within the mine, there were remarkably no injuries or deaths due to the advanced planning of RTKC (Krahulec 2016). 

Photograph 5: Manefay Slide. Courtesy of Kennecott Utah Copper

Chris Carter was the President of Mining and Concentrating for RTKC during the Manefay slides. During a recent oral history interview, Carter discussed the planning and management that went into preparing for the slide. 

“Yes, in 2013, when the Manefay slide happened, I was still here in Salt Lake. I had a lot of discussions with mine management at the time about how to manage it, how to communicate it, and how to best be prepared. That’s something that people will never forget either. But obviously, it was well managed, and nobody was hurt.” (Chris Carter 2022)

The Bingham Canyon Mine operation is the largest open pit mine in the world, encompassing nearly 1,900 acres and employing more than 2,400 people and hundreds of contractors. Today, the area north and west of Magna is heavily used for mining, railroad and highway transportation, and industrial development. 

On November 13^th, 1966, Secretary of the Interior, Stewart Udall, announced that the National Park Service recently recommended fifty-seven sites for the National Historic Landmark program, including the Bingham Canyon Mine. Udall stated that these landmarks processed “exceptional value and are of national significance in commemorating and illustrating the history of the United States” (National Park Service 1966). As the first and largest open pit mine in the world, it played an integral role in the history of mining.