Underground Coal Mine May Have Started Devastating Marshall Fire

A new report suggests that a smoldering underground fire may be linked to the massive blaze that decimated neighborhoods in Northern Colorado last month.

The Los Angeles Times detailed the history of underground coal mine fires starting devastating wildfires across the West, including Colorado. Reporters surmise that abandoned coal mines underneath Boulder County may have been a factor in igniting the Marshall Fire on December 30, 2021.

Investigators are still trying to figure out how the intense blaze started, which left at least one person dead and over 1,000 homes either damaged or destroyed. Initial reports suggested the Marshall Fire originated on the property belonging to a religious group deemed a "cult."

But the LA Times' report points to a history of coal mine fires sparking flames on the surface:

"Could smoldering coal have started such a fire? History shows the answer is yes, with at least two Colorado blazes in the past 20 years blamed on mine fires that spread to the surface. And in Montana, last summer, slow-burning coal reserves fanned by winds sparked a pair of blazes that burned 267 square miles on and around the Northern Cheyenne Indian Reservation."

Reporters specially mentioned the Marshall Mine, which sits underneath an open-space park owned by the city of Boulder. A 2019 report for the Colorado Division of Reclamation, Mining and Safety noted that the mine's "fire’s activity is very low and thus presents little potential to start a surface fire."

"The state mining division said it was not notified of any changes at the mine fire since the 2019 report," according to the LA Times.

The Boulder County Sheriff's Office confirmed to KUSA-TV that they are investigating the mines as a potential origin point, but declined to specify which ones.

Even if the mines were responsible for the fire, state and local officials have no authority to quell the flames below the surface. That responsibility falls to the property owners.