The underground fire burning for weeks in a Utah coal mine could disrupt power generation at two of the state’s biggest power plants, according to the Bureau of Land Management. And putting it out will require an extensive program of drilling and flooding the mine with water and foams, lasting weeks if not months.
Emery County’s Lila Canyon Mine has been burning since Sept. 20, idling 230 workers and cutting off production from Utah’s busiest coal mine. Federal authorities have barred anyone from entering the mine, given the dangerous conditions, making it all but impossible to fight the fire. That’s about to change.
The mine operator has drilled at least two emergency boreholes into the mine to sample its air and craft a plan for putting out the fire smoldering in a coal seam, hopefully without destroying the mine in the process.
In the meantime, Rocky Mountain Power’s two primary Utah power plants, Hunter and Huntington, also in Emery County, have lost access to one of their principal coal suppliers, according to an environmental assessment (EA) conducted by the BLM. The two plants accounted for 37% of the power generated in Utah last year.
Utah’s largest utility, RMP is a subsidiary of the multistate power provider PacifiCorp, which has been monitoring the situation at Lila and contacting coal suppliers.
“At this time, it is difficult to assess the specific impacts that the Lila Canyon fire may have on operations at PacifiCorp’s Utah coal-fueled power plants,” said RMP spokesman Dave Eskelsen. “We will continue to ensure there are no disruptions of electric service to our customers and will utilize our diverse multi-state generation portfolio to maintain reliability of service.”
Lila Canyon operates on 5,549 acres of federal and 1,280 acres of state coal southeast of Price, yielding Utah’s highest quality coal at a rate of about 3.5 million tons a year, or about a quarter of Utah’s current coal production. About 40% of its output was trucked directly Hunter and Huntington last year, covering a fifth of their consumption.
“Though these plants do not rely solely on Lila Canyon Mine coal, Lila Canyon is an important volume to these local power generators,” the EA states. “These plants would not be able to readily replace this coal from the domestic market.”
The mine’s parent company, Ohio-based American Consolidated Natural Resources, has not responded to repeated emails seeking comment since the emergency began five weeks ago, including two emails sent Tuesday.
The BLM conducted the environmental review in response to the operator’s proposed plan for fighting the fire, which could burn indefinitely and leave the mine permanently shuttered.
The fire was trigged in a coal pillar through spontaneous combustion, a not uncommon risk for mines in the Book Cliffs of Utah and Colorado.
According to Jurgen Brune, a professor at the Colorado School of Mines, these kinds of fires often result in the end of the mine because either the fire can’t be extinguished or putting out the fire with floodwaters destroys the mining equipment, worth hundreds of millions of dollars.
“Spontaneous combustion happens with certain coals, particularly in the western U.S., when you expose these coals to just the right amount of oxygen and just the right amount of airflow, then the coal can spontaneously combust,” Brune said.
So-called “sponcom” fires have been burning for years in some Colorado mines.
“Normally when you want to put out a fossil fuel fire, you cut off oxygen,” Brune said. “But in a mine that is very extensive underground, it’s often difficult because the sponcom fire requires only very low oxygen,” Brune said. “The coal itself already has oxygen in it. So in some cases you can you can sustain this sponcom fire without any external oxygen.”
The Lila mine was successfully evacuated Sept. 20 with no injuries reported. Although no one was trapped inside, the operator deployed its mine rescue team and Wolverine Fuels, a competitor operating mines elsewhere in central Utah’s coal country, dispatched two more teams, according to text messages to and from the Utah Office of Coal Mine Safety that were obtained through a document request.
Federal regulations require at least three teams respond to emergencies, according to a Utah Labor Commission spokesman. He said they entered the mine to conduct “recovery of mine” operations, but he was not able to specify what exactly that entailed.
A few weeks into the emergency, the operator was able to drill two boreholes into the part of mine that is burning.
“The air sampling and visual data [the operator] has collected indicates that the elimination of oxygen in the mine has prevented the fire from spreading but that it continues to smolder,” the EA states. Based on this data, the operator sought permission to drill more holes to seal the burn area from the surface and dewater a section of the mine to flood the burn area.”
The new plan, approved by the BLM on Oct. 21, is to drill 35 boreholes from six pads, construct temporary roads to access these drill sites and an aboveground pipeline, and to seal the mine with a cavity-filling compound known as phenolic foam.
The BLM conducted its study without public involvement because of the need to make a decision quickly.
The firefighting efforts could take months to complete, but even if the fire is put out, it remains unclear whether Lila Canyon would come back online anytime soon.