In the late nineteenth and early twentieth centuries, coal mining was the most important industry in Colorado. Coal mines served as the crucibles of empire, churning out the fuel needed to power the railroads, precious-metal mines, and smelters that helped develop the region. They were also contested sites of worker resistance and rebellion where the power dynamics of industrial capitalism were acted out in tragic ways.

Although it is no longer mined in Colorado at the rates it once was, coal has maintained its relative importance to the state’s energy economy through the present. Today, coal mining remains an important industry in the Moffat County, and coal-fueled power plants provide electricity to hundreds of thousands of residents along the Front Range. These coal mines and power plants are sources of air and water pollution, and the industries coal helped fuel are equally pollutive.

Formation of Coal

About 70 million years ago, during the late Cretaceous Period, much of Colorado was covered by a shallow, tropical sea. When the uplift of the Rocky Mountains began about a million years later, it pushed up the inundated land, giving rise to many swampy bogs. It was in these bogs that Colorado’s coal began to form as millions of years of the sun’s energy became trapped in vegetation that died and decomposed on top of itself. The plant material was gradually compressed into a primordial muck that eventually hardened into coal.

When engineer Ferdinand V. Hayden surveyed the geology of Colorado in the late 1860s and early 1870s, he identified several areas that held vast coal reserves. These included the Raton Basin in southern Colorado, whose coal Hayden described as being “inexhaustible and of excellent quality,” as well as the northwest part of what was then Colorado Territory.

The Advent of Industrial Coal

The earliest coal mining in Colorado took place in the late 1850s near the fledgling town of Denver, but industrial development of the state’s coal resources awaited the arrival of William Jackson Palmer in the late 1860s. Over the next two decades, Palmer turned coal into Colorado’s most important commodity. In addition to founding the tourist town of Colorado Springs in 1871, Palmer opened dozens of new coal mines in southern Colorado, and his Denver & Rio Grande Railroad (D&RG) brought that coal to market in Denver. To manage his new coal empire, Palmer started Colorado Coal & Iron, which eventually became Colorado Fuel and Iron (CF&I), arguably the state’s most powerful coal company. The southern Colorado towns of Trinidad and Walsenburg became important hubs of coal mining and transport, with the latter known as “The City Built on Coal.”

Coke and Industry

Coal mining in Colorado developed alongside precious-metal mining. In addition to providing the fuel needed to transport gold and silver ore, coal also warmed the homes of residents in Denver and other mushrooming Front Range cities.

By the 1860s, as gold and silver miners left behind panned-out streambeds and began extracting more metal-bearing ore from the mountains, it became apparent that extreme heat was needed to separate gold and silver from the rock that held it. Coal would provide that heat, but not just any coal would do. Smelters, the heat-driven facilities that melted gold and silver ore to extract the metals, required coal that would burn hot enough to melt rock. This type of coal, a densely layered type called coking coal, was formed by the supercompression of underground coal seams. When heated without oxygen, coking coal turns into coke, a fuel that burns hot enough to melt rock and forge steel.

In the 1880s, coke became even more essential in Colorado, as it fueled William Jackson Palmer’s steel mill in Pueblo. Coking coal was most commonly found in Colorado’s southern coalfields, making those fields even more important to the state’s industrial economy in the late nineteenth and early twentieth centuries.

Major Coal Mining Locations

As Palmer’s southern coalfields coalesced in Las Animas and Huerfano Counties, railroad expansion allowed other parts of the state to become major coal producers as well. In 1881 the D&RG reached Crested Butte, in northern Gunnison County, which would contain some of the most productive mines in the state; it was also the site of the grisly Jokerville Mine Explosion that killed fifty-nine workers in 1884. Toward the end of that decade miners began tapping coalfields in Boulder County, which fueled the growth of towns such as Louisville and Lafayette in the 1890s.

Garfield County in western Colorado also held productive mines, including the volatile Vulcan Mine, which suffered three deadly explosions between 1896 and 1918. In the early 1900s, thanks to the completion of the Moffat Road rail line, a relatively smaller coal industry developed in Routt County in the northwest part of the state. After the Moffat Road reached Craig in 1913, the coal beds of Moffat County could be tapped, too.

By 1917 Colorado had 238 coal mines operating throughout the state, most of which were divided between three companies: CF&I, Rocky Mountain Fuel Company, and Victor American Fuel Company. That year, the state’s coal mines produced a total of some 12.5 million tons of coal, an increase of nearly 2 million tons from the previous year.

Even as it gradually lost market share to oil and natural gas, coal mining continued throughout the twentieth century in Colorado. In Moffat County, for instance, production reached more than 100,000 tons annually between 1943 and 1951. Mining in the state also shifted during this period from deep mining, the kind that sent miners far belowground, to open-pit mining, where heavy machinery is used to excavate shallower coal seams. By the 1960s, coal production had dwindled to the point where the industry had only a small fraction of its earlier power and influence.

Work in the Coal Mines

Working in coal mines was dirty and dangerous, and labor conditions were dismal and underregulated. Most coal mines grouped together men from more than a dozen different nations and backgrounds, including Austria, Britain, Greece, Italy, Mexico, Poland, and the United States. In the 1880s, coal miners worked from fourteen to sixteen hours per day for paltry wages that were often paid in scrip, a kind of currency that could be used only at company stores. Since many coal camps were remote, these stores were often the sole local source of food and supplies, keeping miners tethered to the company. Moreover, coal companies such as CF&I often built whole company towns, where workers paid rent to live. Along with company stores, company housing ensured that most wages were returned to the company.

In the mines, workers inhaled coal dust all day long, which led to the devastating respiratory disease known as black lung. Mine shafts could collapse or flood. Rock slides and fires were also common; in 1917 the state mine inspector reported that sixty-six miners died from routine accidents, including “falls of rock, falls of coal, mine cars and motors, explosives,” and “electricity.” In addition, methane and other flammable gases released from coal beds often built up in the mines, and each morning an inspector had to check the air quality before work could begin. Employed since the early 1800s, safety lamps, whose flames burned differently when held close to flammable gases, helped determine whether a mine’s air quality was safe. Davy lamps with longer wicks were also used to burn off harmful gases.

Most mines employed inspectors to monitor safety conditions, but even a slight mistake could spell instant death for dozens of miners. This was the case in the Hastings Mine Explosion, Colorado’s deadliest mining disaster, which occurred north of Trinidad in 1917. For unknown reasons, the mine inspector took apart his safety lamp and attempted to relight it with a match, triggering a gas-fueled explosion that killed 121 workers. In addition, some mines exploded despite being declared safe; this occurred in the Jokerville Mine blast of 1884, which killed fifty-nine miners. A total of eighty-five workers perished during the three explosions of the Vulcan Mine between 1896 and 1918. These disasters reflected the troubling trend of Colorado miners dying at a rate of twice the national average between 1884 and 1912.

Labor Strife

Coal miners were victims of owner exploitation and hazardous working conditions, and they often tried to improve their lot. As early as the 1870s, they organized strikes and walkouts, and later they joined unions such as the United Mine Workers of America (UMWA), formed in 1890. The first UMWA local in Colorado was formed in the Boulder County town of Erie that year, and the union organized its first major strike during the financial calamity of 1893-94. Thousands of coal miners across the state walked off the job, hoping to produce a coal shortage that would force owners to meet their demands of abolishing company stores and paying workers in cash. In the end, however, there were not enough walkouts to produce a shortage, so miners went back to work under prestrike conditions. By 1900 similar actions had earned some hard-won improvements, including a state law mandating an eight-hour workday, but coal miners had to pressure companies such as CF&I to follow the laws.

Recognizing the power of strikes, mine owners and companies took them seriously, employing both economic oppression and violence to stop them. Owners fired striking workers and hired strikebreakers to work for lower wages than strikers were demanding, hoping to end the strikes. When these approaches failed, mine owners and companies raised citizen militias or petitioned the state to call in the National Guard to force miners back to work.

In Colorado the UMWA was most active in the early twentieth century, with thousands of members joining strikes in the southern coalfields of Fremont, Huerfano, and Las Animas Counties. A strike in 1903–4 again called for the abolition of scrip and company stores, as well as implementation of the state’s eight-hour workday law. The failure of that strike led to rising tensions that exploded again in the spring of 1913. The UMWA led a strike in the southern coalfields that involved about 90 percent of the state’s coal workers and resulted in the Ludlow Massacre when National Guard members fired on striking miners and set the strikers’ tent colony on fire. It was the deadliest labor conflict in state history.

Coal mining conditions were hardly improved for miners by the time another major conflict broke out in the late 1920s. In 1927, during a strike in the northern coalfields of Weld County, the Colorado State Police (then known as the Colorado Rangers) opened fire on strikers and their wives at the Rocky Mountain Fuel company town of Serene, killing six and wounding twenty.

Strikes and labor conflict became less common after the passage of the federal Wagner Act in 1935, which recognized workers’ rights to unionize. Still, there remained periods of strife, such as in 1978, when miners at the Allen and Maxwell Mines in Las Animas County walked off the job for three months as part of a national strike organized by the United Mine Workers.

Environmental Effects

In addition to the injuries and health hazards to workers, coal mining has produced a number of negative environmental effects that Coloradans continue to deal with today. Air pollution is the largest environmental cost of coal production. To make the air in coal mines breathable, methane and other harmful gases are vented out into the atmosphere, contributing to local smog and global climate change. The West Elk Mine in Gunnison County is the largest methane emitter in Colorado, belching out emissions in 2017 that equaled those of 98,000 cars. Abandoned coal mines also release methane. Nationwide, coal mines account for almost 10 percent of all methane emissions.

In addition, mines often need to be expanded to maintain their profitability, which leads to deforestation and other forms of habitat destruction. As such, environmental groups often take the coal industry to court over mine expansion as well as pollution. At the West Elk Mine, for example, a proposed expansion into a designated roadless forest resulted in years of litigation before it was ultimately blocked in 2020—but only after the company illegally bulldozed a road through the area.

Coal-fueled power plants are another major source of pollution. In 2020 The Denver Post named Colorado’s six coal-fired power plants among the state’s top ten greenhouse gas emitters. Coal-fired power can contaminate water sources, too; in 2019 an investigation by the Platte River Power Authority found that groundwater near the Rawhide Energy Station in Larimer County was contaminated with selenium, a chemical that can harm both humans and wildlife. Aware of coal’s ongoing potential to harm air and water quality and wildlife, environmental groups such as the Sierra Club and WildEarth Guardians have repeatedly sued to stop the expansion of the coal industry in the state.

Today

Despite its environmental effects, coal mining continues in Colorado today. In Moffat County, coal still underwrites the local economy. As much as 46 percent of the total property value in the county is generated from its two major coal mines, the Colowyo and Trapper Mines. The Craig Station power plant, completed in the early 1980s and operated by the Westminster-based Tri-State Generation and Transmission company, provides hundreds of jobs in Moffat County and supplies power to some 250,000 square miles in Colorado, Nebraska, New Mexico, and Wyoming. Despite its importance to local economies in places like Craig, Tri-State has decided to shut down the company’s coal-fired plants in Colorado and New Mexico by 2030.

Even though production has declined almost every year since 2012, Colorado remains the eleventh-largest producer of coal in the country, with nearly one-quarter of its coal exported to other countries. The West Elk Mine remains one of the state’s largest, employing around 220 people and producing nearly 4 million tons of coal in 2016. Coal from within and beyond the state provides more than half of Colorado’s net electricity generation. This means that coal will play a part in Colorado’s economy for at least the next decade, even as state and industry leaders move toward less pollutive and renewable energy sources.