Officials are calling for a contractor to extinguish nearly 6,000 cubic yards of burning coal on Menefee Mountain.
A half-dozen contractors attended a pre-bid meeting outside of Mancos last week to survey piles of burning coal left over from historical mines that date back to the 1920s and 1930s. The coal fires were ignited last summer when the Weber Fire torched some 10,000 acres of forest southeast of Mancos.
"Coal mining on Menefee Mountain is turning out to be more extensive than anyone thought," said Steve Renner, project manager for the Colorado Division of Reclamation, Mining and Safety (DRMS).
The Weber Fire passed over numerous historical and abandoned coal mines, igniting both coal refuse piles and coal seams scattered across steep slopes along BLM Road 4556. Bid documents identify seven coal fire locations scattered across 10 acres of private, state and Bureau of Land Management lands along Menefee Mountain.
The project calls for excavating and mixing burning coal with a fire retardant foam and water mixture until the materials cool to less than 100 degrees.
The 51-page bid document reveals the largest deposit of smoldering coal is located at the Freeman Mine site near Flint Rock Point. There, some 3,000 cubic yards of coal refuse will be need to be extinguished using approximately 30,000 gallons of water and foam. In addition to major road repair at the site, the bid document states that all standing dead ponderosa pines must be felled prior to starting fire suppression efforts.
The smallest burning coal site is located at Spencer Mine. An estimated 500 gallons of water and foam are expected to suppress approximately 50 cubic yards of a burning coal seam. An open mine shaft will also be sealed at the location.
The Mancos Hill Mine and the Mancos Number 1 Mine sites are so inaccessibly steep that excavation and cooling will be required to be done by hand. Other locations included in the project are Mancos Number 2 Mine and the State Land Mine. The final site contained in the bid document is a line of eight coal seam fires along roadways south of the mines.
Bids will be opened Aug. 13, and construction is expected to start in September.
Some type of roadwork is projected at each of the sites to handle heavy machinery and water trucks. The bid document states that each site and any new roadwork performed must be restored to natural conditions.
Once the coal fires are smothered, the project calls for revegetation of approximately 10 acres across the seven mine sites. It's estimated that 10 tons of hay or straw mulch and an additional 500 bales of wood straw mulch will be needed to help reclaim the landscape.
Previous reports said the smoldering coal was belching small but steady streams of acrid smoke and generating surface heat of up to 600 degrees Fahrenheit. Reports also stated that the smoldering coal piles were oozing a hot, black tar-like substance. If left alone, the coal fires could smolder for decades, generally moving a couple of inches per year.
Kay Zillich, a BLM abandoned mine specialist, previously told the Cortez Journal that an unwary hiker could step on what looks like solid ground, but break through the crust and fall several feet into a searing hot coal oven.
"Under the soil surface, the coal burns away, leaving an unstable layer underneath forming fissures," she explained. "It is the same way a coal briquette retains its shape after it has completely burned."
Miners used hard-rock mining techniques to extract the low-grade coal from the Menefee Formation. The coal was transported to market via the Rio Grande Southern railroad.
