Mascotte Tunnel

The Mascotte Tunnel is remembered as a groundbreaking feat of construction. Built by the Bingham Consolidated Mining and Smelting Company, it was used to drain the mines and served as an ore-hauling corridor for many years.

The story of mining in Utah—or more specifically the Salt Lake Valley and bordering mountain ranges— begins with the coming of Colonel Patrick Edward Connor and his 700 to 750 troops to the Salt Lake Valley in 1862. Connor and his troops would establish Camp Douglas (later Fort Douglas) on the east bench of the Wasatch Mountains overlooking Salt Lake City. To keep his men occupied, Connor sent them up into the Oquirrh Mountains to prospect and in 1863, his men discovered silver in what is now known as Bingham Canyon. That the Oquirrh Mountains contained valuable ores was not a secret to Brigham Young, the leader of the Church of Jesus Christ of Latter-Day Saints, and top political figure in the Salt Lake Valley; however, Young wanted to keep this knowledge a secret (May 1989; Sdler 1979). Young knew the Oquirrh Mountains contained valuable ore as early as 1848, after he sent the Bingham brothers, Thomas and Sanford, with herds of horses and cattle to graze in the upper reaches of the canyon now known as Bingham Canyon. The Bingham brothers soon informed Young about the ores they had discovered in the canyon and Young advised that they remain silent about their discovery. Young thought labor was better spent in the establishment of a viable community in the Salt Lake Valley, and he was also concerned that mining would attract Gentiles (non-church followers) and the rowdy population typically associated with mining and mining towns. He feared that their presence would have a negative effect on the society he was trying to establish (Crump 1994). 

On January 3, 1866, the first claim in the Lark area was made and it was not long until claims had sprung up across the mountainside. It is likely the hillsides were covered with tent structures and hastily constructed wood-frame structures (Sandstrom 1978). Several large mining properties would develop out of these initial claims, the largest and most successful mines in the area being the Brooklyn and Old Lead Mines. Combined, these properties would recover hundreds of thousands, if not millions of dollars from the rich silver and lead veins riddling the hillsides. These mines eventually closed due to the decline of silver and lead prices during the difficult economic times of the 1890s following the Panic of 1893. A few years after the mines closed their doors, several mines in the area were consolidated under the Dalton and Lark Gold, Silver, and Lead Mining and Milling Company. Times were tough for the new conglomerate though, as silver prices remained low. In addition to the nationwide economic conditions, a fire destroyed one of their concentrators along with several pieces of equipment. To make matters even worse, underground mining operations had encountered aquifers, which were slowly filling up the lower levels of the mine with water. This was a common problem in underground mining and was typically solved by pumping the water to the surface. Unfortunately, at the time the company was unable to acquire pumps that could efficiently remove the water, thus stalling mining operations (Anderson 1980).

The solution to the water problem was the construction of the Mascotte Tunnel within the town of Lark. The tunnel was constructed by Bingham Consolidated Mining and Smelting Company (Bingham Consolidated) between 1901 and 1902 to drain the Brooklyn and the Dalton and Lark shafts (Billings 1952). In addition to alleviating the water problem, the tunnel also served as an ore-hauling corridor. The Mascotte consisted of three components: the tunnel, the ditch, and the pond that received water from the Mascotte Tunnel via the Mascotte Ditch (Hoffman 2005). The Mascotte Tunnel was originally 8,000 feet (ft) long and later lengthened to 14,000 ft to intersect the Ohio Copper ore body (Hoffman 2005). The Mascotte Ditch would come to serve as the water source for the town of Lark, with Lark residents drawing water directly from the ditch. Sometime between 1901 and 1907, Bingham Consolidated piped the water coming from the Mascotte Tunnel to a tap near the tunnel entrance. As the town of Lark grew during the 1930s to the 1950s, the Bingham Consolidated constructed a formal water system that included fire hydrants, a buried water pipe system, and a water tank (McDonald 1946). During a cultural resources survey in 2014, the water tank was still in use (Adams et. al. 2014) and it is highly likely that Rio Tinto is still using it. 

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Mascotte Tunnel overview 1950 (Richardson 2017).

Prior to the Mascotte Tunnel, an earlier attempt to drain the mines was conducted by the Dalton and Lark Mining Company (Dalton and Lark) in 1895. Then known as the Bingham Tunnel, excavation had reached a length of 160 ft, but excavation ceased in in late 1895 when Dalton and Lark was hit by financial troubles and was unable to continue tunneling operations. Tunneling operations remained inactive throughout the remainder of the 1890s due to the nation-wide economic depression. By 1900, however, the economy had improved, and plans were developed to begin tunneling once again. The Mascotte name was first used in early 1900 and originated from the name of a placer mine owned by Dalton and Lark. At that time, the Dalton and Lark properties were sold, and the full name of Mascotte of Bingham Mining was chosen to distinguish shares of the company that a handful of stockholders refused to sell to the new owner, the Bingham Consolidated Mining and Smelting Company. By the end of 1900, the stockholder difficulties were settled, and the mine once again operated as the Dalton and Lark while the tunnel retained the name of Mascotte. Digging of the tunnel commenced in early 1901 and by August of that year, the tunnel reached a length of 1,070 ft. Men labored around the clock using hand drills and churned out about seven feet per day (Strack 2018). 

By March 1905, the Mascotte Tunnel was nearly 8,000 ft long and provided water drainage for all the Bingham Consolidated mines. A large stream of water flowed from the tunnel and into the valley below where it was used for irrigation. At the 8,000 ft length, the tunnel was nearly under the Dalton and Lark workings and plans were to continue drilling farther into the mountain and at the same time cut upraises and crosscuts from the main tunnel to intersect the various ore veins known to exist. Once the tunnel connected with the Dalton and Lark workings, the ore was shipped via the tunnel, which was considerably cheaper than hoisting it up the Dalton and Lark shaft. Ores from the upper levels were dropped down to the 1,070 or 1,100 ft levels, then loaded into skips (small rail cars) that were dumped into chutes that emptied onto the Mascotte level. The Lark mines were producing 200 to 300 tons of copper and 50 to 100 tons of lead per day and a newly constructed electric locomotive along the Mascotte Tunnel was capable of hauling 60 tons of rock out of the tunnel per load. The pride of the operation was the power plant that was providing compressed air for the operation of 17 machine drills and 7 hoists. The air was supplied through a two-mile long pipeline (Strack 2022a). 

Near the outlet of the Mascotte Tunnel was the Dalton and Lark Railroad (D&L), on which ore and supplies could be transported. The D&L was established in January of 1902 and connected with the Rio Grande Western Railroad (RGW) at Revere station, later renamed Dalton. The railroad replaced the earlier four-mile-long horse tramway. Unfortunately, the rails for the newly laid railroad were too light to support the 10-ton locomotive and derailments were a common occurrence. By October 1902, however, the light rails were replaced with the heavier standard gauge rail and a trial run of 59 cars was conducted without incident. By May of 1903, 100 tons of ore was being taken from the Brooklyn mine while a veritable river of water issued from the Mascotte Tunnel. In November of 1903, the RGW bought the D&L from Bingham Consolidated Mining and Smelting Company and renamed it the Dalton and Lark Spur (Strack 2022a). 

Between 1905 and 1907, Augustus Heinze, an investor with ties to New York City and with previous mining investment experience in Montana, acquired control of the Ohio Copper Company and a large interest in the Bingham Consolidated Mining and Smelting Company (Deseret Evening News [DEN] 17 September 1907:6). In an attempt to increase the production and transportation of ore from the Ohio Copper and Bingham Consolidated mine operations, Mr. Heinze purchased the Mascotte Tunnel from the Bingham Consolidated company in 1907 and established the Bingham Central Railway Company. The goal of this company was twofold: first, to expand the existing Mascotte Tunnel to facilitate the transport of ore from multiple mines along the eastern slope of the Oquirrh Mountains near Bingham; and second, to construct a new railroad between Bingham and Salt Lake City which would transport ore from the mines to mills and smelters near Salt Lake City (DEN 17 September 1907:6; McDonald 1946:69; Railway Gazette 1907:277) and to the newly constructed Ohio Copper gravity-feed concentrator mill at Lark (McDonald 1946:69).

Transportation in the town of Lark was also significantly impacted by the construction of the Mascotte

Tunnel and D&L railroad line. Prior to the construction of railroad lines to Lark in 1902, all

supplies were brought to Lark using freight wagons over poor and dangerous roads between Lark and the Bingham area (McDonald 1946:73). With the advent of the D&L, supplies and ore shipments were transported by rail from Lark to the Revere (later Dalton) Switch station on the Bingham Branch of the Rio Grande Western railroad. For passengers and mail, a buggy wagon—commonly known as the White Top Buggy—was used on the existing stage line between Lark and the Revere Switch station (McDonald 1946:73). From the Revere station, passengers could board trains for Bingham or Salt Lake City. Following the growth and development of Lark in the early twentieth century, paved roads and highways, including State Route 111, were constructed between Lark and neighboring towns.

In 1929, the United States Smelting, Refining and Mining Company (USSR&M) acquired ownership of the Lark mines and in 1941, they moved operations out of upper Bingham Canyon to Lark. By 1949, USSR&M had constructed a new mining plant that included shops, offices, and a medical clinic. Soon after, the town of Lark expanded to the east with a new housing development known as Lark Heights (Billings 1952; Strack 2022b). In 1948, USSR&M began the construction of a new tunnel in Lark (Deseret News [DN] 16 April 1951:5), one of the most notable developments within the town of Lark during this period. Known as the Bingham Tunnel (aka the Lark Tunnel) (Billings 1952), its purpose was to connect with the old Niagara Tunnel and to replace the aging Mascotte Tunnel (DN 16 April 1951:5). 

Prior to the opening of the new Bingham Tunnel, tragedy struck on July 16, 1950 (Salt Lake Telegram [SLT] 19 July 1950:17) when a fire at the lead mine in Lark—then operated by the U.S. Smelting Refining and Mining Company—killed five mine employees. As a result of the fire and smoke, two miners were asphyxiated within the Mascotte Tunnel, while three others were trapped underground. The two asphyxiated miners recovered from the Mascotte Tunnel were hoist man Horace Martin Seal (59 years old) and assistant master mechanic Byron Gray Thomas (46 years old). The three trapped miners were pump operator Leland David Neilsen (38 years old), electrician Robert Gordon Meyerhoffer (38 years old), and general mine foreman Clyde Wilson Augustson (41 years old (Richardson 2016; SLT 19 July 1950:17). It was an agonizing 25 days before the fate of the trapped miners was known. Unfortunately, they did not survive, and their bodies were found at the 1,000-foot level in 4 feet of water on August 9, 1950 (The Midvale Sentinel [MS] 11 August 1950:1). In a tragic twist of irony, two months prior to the tragic mine fire, the Lark mine was awarded the Joseph A. Holmes Safety Association certificate of honor in May of 1950 for its safety record of 1,449,615 man-hours without a fatal accident (The Bingham Bulletin [BB] 12 May 1950:11). 

Lark Mine Fire July 16, 1950.

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Rescuers at mouth of Mascotte Tunnel (Richardson 2017).
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Rescuers entering Mascotte Tunnel (Richardson 2017).
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Entry into Mascotte Tunnel (Richardson 2016).
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Damage inflicted by fire (Richardson 2016).

Lark Mine Fire July 16, 1950.

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Rehabilitation of 5728 incline 1400 level to 1200 level (Richardson 2016).
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Rescuers inside Mascotte Tunnel, Benton Boyd, right front (Richardson 2016).
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One of the victims being taken out of the mine (Richardson 2017).
Rescuers take a meal (Richardson 2017).
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Family and friends stand vigil over mine rescue (Richardson 2017). 

With great emotion, Lois Elaine Fahrni Kieffer (then 9 years old) recalls the mine fire and standing vigil on the dump above the Mascotte Tunnel waiting for the bodies to be brought out. One of her friends lost a father and grandfather in the fire and another friend lost a father. Kieffer’s father was working at the mine that day and she and her mother feared that he may have been in the mine when the fire started. After what must have seemed like an eternity, her father showed up at home, still in his work clothes. Their relief was short-lived, however, since he informed them that he was on his way to the Tooele side of the mine to see if the mine could be accessed from that side. The Tooele-side tunnel was so filled with smoke that it was impossible for them to enter (Lois Kieffer, personal communication 2022).

The Bingham Tunnel was completed in 1951 and measured 3.9 miles in length, with the main portal located approximately 440 ft northeast of the existing Mascotte Tunnel portal (Billings 1952). The Mascotte Tunnel remained in operation until either late 1951 or mid-1952 (Adams et. al. 2014; Strack 2018). 

In 2014, Kennecott Utah Copper LLC (Kennecott) contracted with Logan Simpson to conduct a Class III Cultural Resources Inventory (inventory) in Lark. The inventory was performed in advance of proposed future expansion of mining activities in the vicinity of the abandoned Mascotte Tunnel. The Logan Simpson survey crew documented the Lark townsite (designated as archaeological site 42SL714) and identified two mining tunnels, a narrow-gauge railroad, standing structures, pads, depressions, foundation, retaining and terrace walls, roadbeds, municipal water system, electrical and communications infrastructure, wastewater flumes, and historic artifacts. The two tunnels identified were the Bingham Tunnel and the Mascotte Tunnel. The Bingham Tunnel was retrofitted with a poured concrete portal and concrete-lined walls and arched ceiling and was still in use as of 2014. The abandoned Mascotte Tunnel, which was shut down in 1951 or 1952 (Adams et. al. 2014; Strack 2018), once contained a wooden flume, a narrow-gauge railroad, overhead powerline structures, and a framed portal entrance with upper slope shoring. All of this associated infrastructure had been removed prior to the 2014 recording and the railroad ties and rails had been stacked near the entrance. The entrance measured approximately 5 ft by 5 ft. As of 2014, the tunnel was framed and supported by steel I-beams and railroad ties. The portal roof was partially covered with waste rock and the entrance had been gated and locked (Adams et. al. 2014). 

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Mascotte Tunnel Portal, condition as of 2014, facing west (Adams et. al. 2014).

Like all mining towns established in the nineteenth and first half of the twentieth centuries, Lark was intricately tied to the companies operating the Lark mines. No event in the history of Lark has exerted a greater impact on the development of Lark than the construction of the Mascotte Tunnel. The Mascotte Tunnel is the foundation from which all future mine developments and community expansions took place. 



Adams, Jesse, Danny Mullins, Michael Ligman, and Seth Button. 2014 A Class III Cultural Resources Inventory for Areas Potentially Impacted by Kennecott’s East Waste Rock Extensions, Salt Lake County, Utah. LSD Technical Report No. 125609a. Logan Simpson Design, Salt Lake City, Utah. 

Anderson, Rennette. 1980 Lark Becomes a Ghost Town as Progress Takes Her Toll. 3 January:1,3. The Jordan Valley Sentinel, Midvale, Utah. 

Billings, Thomas Parry. 1952 History of the Bingham Mining District. Located in the Wilbur H. Smith Papers Special Collections. University of Utah, Salt Lake City, Utah.

Bingham Bulletin, The (BB) 1950 US. Mine Gets Safety Honor. 12 May:11, Bingham Canyon, Utah).

Crump, Scott.1994 Bingham Canyon. Utah History Encyclopedia, electronic document, accessed November 8, 2022

Deseret Evening News (DEN) 1907 Heinze in Utah. 17 September:6. Salt Lake City, Utah.

Deseret News (DN). 1951 Lark Tunnel nears Completion as Crews Finish Drilling Work. 16 April:5. Salt Lake City Utah.

Hoffman, Eva J. 2005 Oquirrh Mountains Mining and the Environment. U.S. Environmental Protection Agency, Region 8. Denver, Colorado. 

May, Dean L. 1989 Economic Beginnings. In Utah’s History. Richard D. Poll, General editor, pp. 193-215. Utah State University Press, Logan, Utah. 

McDonald, Dora. 1946 History of Lark. In Communities of Jordan School District, pp.65-77. Vol. 1. Jordan School District, West Jordan, Utah

Midvale Sentinel, The (MS). 1950 Lark Mine Yields Bodies of Three Trapped Workers. 11 August:1. Midvale, Utah.

Railway Gazette. 1907 September 6, Volume 43, Number 10.

Richardson, Steven. 

2016 Lark Fire 1950. Lark, Utah Album. Facebook,

2017 Lark Fire 1950. Lark, Utah Album. Facebook,

Sadler, Richard W.

1979 The Impact of Mining on Salt Lake City. Utah Historical Quarterly 47(3):236-253. 

Salt Lake Telegram (SLT). 1950 Wet Hoist Motor Delays Lark Rescue Work. 19 July:17, Salt Lake City, Utah.

Sandstrom, Lillis. 1978A Brief History of Lark. Lark Ward of the Riverton Utah Stake of the Church of Jesus Christ of Latter-day Saints, Lark Utah.

Strack, Don B. 

2018 Mascotte Tunnel/Bingham Central Railway. UtahRails.Net. Electronic document Mascotte Tunnel/Bingham Central Ry. (, accessed December 19, 2022.

2022a Bingham Consolidated Mining Company. UtahRails.Net. Electronic document Bingham Consolidated Mining Co. (, accessed December 19,2022.

2022b United States Mining Company. UtahRails.Net. Electronic document United States Mining      Company (, accessed January 20, 2023. 2021 Lark, Utah. Scott Crump Collection. Electronic document Lark, Utah Scenes. (, accessed December 11, 2022.