State and local officials have announced the completion of the Marshall Mesa Coal Fire Mitigation Project in Boulder, Colorado. The project, which addressed a coal seam fire that had been burning underground for over a century, was led by the Colorado Division of Reclamation, Mining and Safety (DRMS) and involved collaboration with the City of Boulder and Mountain View Fire Rescue.
The mitigation work began in October 2024. It required excavation of smoldering coal left from historic mining operations about thirty feet below ground. After this process, DRMS handed off ongoing site work to the City of Boulder, which will now begin trailhead improvements expected to last eight months.
“The Marshall Mesa Coal Fire Mitigation Project is a collaborative effort to strengthen community resilience and reduce wildfire risk. This project exemplifies the power of partnerships in safeguarding our lands, homes, and future generations,” said Congressman Joe Neguse (CO-02).
To prevent future ignition risks, crews blended underground coal with cold soil and rock until it cooled below 80 degrees Fahrenheit before returning it to the excavation site. Unburned coal was also excavated and mixed thoroughly.
After subsurface mitigation concluded, crews restored both northern and southern sections of the area to match natural land contours and planted native vegetation.
“We appreciate the partnership and collaboration with the City of Boulder and the surrounding community to address the issues around the Marshall coal fire mitigation project. With their partnership and working closely with our contractors we were able to excavate problematic areas in the old coal mine and the coal seam to minimize the risk of future ignition,” said Jeff Graves, Director, Inactive Mine Reclamation Program at DRMS. “We will continue to monitor the site for as long as necessary in cooperation with the City as they move forward returning the area to public use through the Marshall Mesa trailhead project.”
With major mitigation completed, responsibility shifts to Boulder’s Open Space and Mountain Parks department for construction of a new Marshall Mesa Trailhead connecting visitors with more than 46,000 acres of city open space featuring 37 trailheads and 161 miles of trails.
“The City of Boulder extends our appreciation to the state and Division of Reclamation Mining and Safety staff for the partnership and coordination to conduct this important coal mine mitigation project,” said Dan Burke, director of City of Boulder Open Space and Mountain Parks. “Now that their hard work is complete, we look forward to creating a whole new Marshall Mesa Trailhead experience to help visitors enjoy Boulder’s remarkable open space.”
Planned improvements at Marshall Mesa Trailhead include new amenities such as restrooms, shade shelters, additional bike racks, picnic tables, benches; upgraded parking; enhanced vehicle access; improved connectivity via direct trail connection to RTD “Park-n-Ride”; better educational signage; an accessible trail for visitors with disabilities; as well as rerouted trails for improved traffic flow.
During construction on these enhancements—which is expected over several months—the trailhead itself will remain closed but most nearby trails are still accessible.
Mountain View Fire Rescue will also install a modern 20,000-gallon cistern at Marshall Mesa replacing an older leaking tank. This upgrade aims to provide immediate water access during emergencies near this high-traffic area.
“Having this asset in such a high traffic location will allow our crews to have water on hand for a quick response in the event of a fire starting near the trailhead, with the goal of limiting spread quickly,” said Rick Tillery, public information officer for Mountain View Fire Rescue.
