Crews encounter 300-degree temperature in burning remnants of Colorado coal mines
Crews tearing apart a 1.5-acre pile of coal mine refuse that has been smoldering for two decades recently uncovered a section which measured 300 degrees Fahrenheit.
The Corley Mine Surface Burn Mitigation Project began in early June. Prior to the recent spike, temperatures inside the pile ranged between 100 and 110 degrees.
The Corley Mine operated between the 1920s and 1990s about nine miles south-southwest of Florence, Colorado. A total of 15 mines were dug over that time at the site. The refuse pile accumulated during the 1950s, according to the Colorado Division of Reclamation, Mining and Safety (DRMS). The pile - approximately 35 feet tall, 150 feet wide, and 300 feet long - is a mixture of lower quality coal and rock/dirt debris that was removed from underground during extraction.
The fire likely started through spontaneous combustion of exposed coal waste, per DRMS.
A company contracted by the DRMS is carrying out the work. They are uncovering the material, quenching it with water, and blending it with equal of amounts of the area's other rock and dirt - which, it can be safely assumed, do not contain coal.
Crews peeled nine acres of surface vegetation away from the mitigation site to prevent the smoldering material from starting a brush fire.
The planned completion of the project is September 4. It is expected to cost $853,000.
Once the excavated pile is mixed and cooled, crews will backfill the site and replant it with seeds from plants native to it.
DRMS finished digging up and extinguishing two former coal mine sites in Boulder County in January. Temperatures found on those sites did not reach 200 degrees, and the mitigation projects helped eliminate those underground fires as a cause of the 2021 Marshall Fire, monetarily the most destructive wildfire in state history.
Right now, DRMS crews are mitigating another underground coal mine site near Glenwood Springs. A coal seam there has burned since 1910. It was blamed for igniting the Coal Seam Fire which burned more than 10,000 acres and destroyed 28 homes in 2002. there reached 600 and 900 degrees earlier this year.
Trails below the site will have intermittent closures due to rockfall danger until the project is completed in early July, if all goes according to plan.
