Historical Markers
Mammoth Mine Explosion Historical Marker
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Mammoth Mine Explosion

Laurel Highlands/Southern Alleghenies


Marker Location:
St. John's Cemetery

Dedication Date:
September 29, 2000

Behind the Marker

Head and shoulders drawing of Col. Moore.
Colonel J.W. Moore, founder of the Mammoth Mine, circa 1882.
In 1879, Colonel J.W. Moore of Greensburg bought 2,000 acres of land in Westmoreland County. Six years later, in 1885, his company opened the slope-entry Mammoth Mine to extract bituminous coal from the rich Pittsburgh seam. markerFirst Mining of Pittsburgh Coal Soon after, the company dug a second shaft mine and constructed beehive markercoke ovens nearby.

Some 176 men and boys worked at the two mines in 1886, producing more than 154,000 tons of coal, most of which went to the coke ovens where another 110 men and boys labored. In 1889 Moore sold the Mammoth Mine and coke ovens to the H.C. Frick Coke Company, which dominated coke production in southwestern Pennsylvania (see markerHenry Clay Frick.)

Broadside of the death announcement
"As a Thief in the Night," newspaper headline, January 1891.
On January 27, 1891, a huge explosion tore through the underground tunnels. According to a local newspaper, "It was about nine o'clock that the explosion occurred and soon a black vapor poured out of the top of the 107 foot shaft, telling those above ground plainer than words could do that death lurked in the depths." All 109 miners who had entered the mine died. "Even the fireboss, William Snaith, who had made out his report at an early hour, showing that the mine was safe, met the same fate that befell those who were permitted to enter the mine only by his order."

Thirty-one men left families behind. The other seventy-eight victims were single men or boys. Many of the miners' bodies were mangled beyond recognition by the force of the explosion, and were buried anonymously in a mass grave.

Soon after the explosion, United Mine Workers of America (UMWA) officers and miners petitioned Pennsylvania governor Robert Pattison to draw attention to the disaster and urge the legislature to enact more effective mine-safety laws. The petitioners wrote, "Over 150,000 of our brothers daily enter the respective mines of the state. In addition to the hardships incident to the working underground, they are, in many instances, in constant danger of meeting the same fate as befell the miners at Mammoth, a fate that has shocked the entire Commonwealth and the country."

The state legislature appointed a commission to investigate the disaster and recommend changes in mine-safety laws. The commission concluded that the explosion occurred due to a number of causes, including an accumulation of combustible mine gas, and the open flames that miners carried to illuminate their work and that ignited the gas. In addition, the commission stated that the mine safety law was "very defective and ambiguous and needs revision and extension, marker requiring much time and labor."
News clipping
Account of the 1891 Mammoth mine explosion, by T. T. O'Malley.

After receiving the investigating commission's report, the state legislature appointed a second commission to propose changes to mine-safety laws. Despite support for new legislation from miners, state mine inspectors, and both commissions, the existing "very defective and ambiguous" laws remained on the books.

The men and boys who perished in the Mammoth Mine explosion were among some 18,000 people who died at Pennsylvania bituminous mines between 1877 and 1940; an average of about 280 deaths each year. The toll peaked at 806 in 1907, when the markerDarr Mine disaster killed 239 men and boys. Thousands more bituminous miners were injured or maimed for life.

Large-scale explosions like the one at Mammoth Mine, however, were atypical of the way most miners died. Bituminous miners usually perished one or two at a time. During the early twentieth century, more underground bituminous miners died from falling rock than any other cause. Other underground miners succumbed when mine cars or locomotives crushed them, they were electrocuted, gas or coal dust ignited and exploded, or black powder or dynamite detonated unexpectedly. Mining was one of the most dangerous occupations in the Commonwealth, and death and injury were a constant threat.

Color photograph of the Mammoth Patch Homes.
Mammoth Mine Patch Houses In the Mt. Pleasant - Latrobe portion of the Connellsville...
For decades mine owners and government did little to stem the tide of death and injury. Coal operators often blamed miners' carelessness, neglect, or ignorance for mishaps. Mine managers also frequently failed to institute mine-safety programs, despite repeated large-scale disasters such as the Mammoth Mine explosion. Miners did cause accidents, but so did owners, who evaded responsibility by blaming accidents on miners and not implementing safety measures.

Miners and the UMWA advocated laws that mandated state inspections. Pennsylvania was the first state government to enact mine-safety laws, beginning in 1869, but during the late nineteenth century, it was slow to enforce these laws. During the early twentieth century, however, the number of state-appointed mine inspectors increased and courts began to find mine operators liable, helping to improve enforcement.

A 1911 law also required bituminous operators to institute first-aid programs, more closely supervise workers to prevent accidents, post safety regulations in various languages, and increase the minimum age for working in mines. State laws also required that skilled miners meet standards of competency, helping to decrease accidents caused by miners. Beginning in the 1920s, these measures helped significantly reduce the number of deaths in the mines.

Large pile of slate.
The unreclaimed gob pile at Mammoth Mine
Beginning in the early twentieth century, some companies also voluntarily developed mine-safety programs. The H.C. Frick Coke Company started a safety program in its bituminous mines that included training rescue and first-aid teams, and posting warning signs in multiple languages. Deaths and injuries, however, continued at the Mammoth Mine despite safety programs, mine inspections, union pressure, and miners' actions. For instance, in 1908 Mike Wilcek died instantly when rock fell from a tunnel roof. Wilcek, a Polish immigrant, left a wife and child.

The H.C. Frick Coke Company continued to operate the Mammoth Mine and coke works until 1927, when it closed and abandoned them. Lessees operated coke ovens there from the 1930s to mid-1940s. Subsequent owners strip mined coal and reclaimed coal from the waste piles near the site of the shaft.
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