The Bull Mountain coal mine south of Roundup recently received state approval to significantly expand the area to be mined using the underground longwall mining method.
The mine plan revision will enable the company to take advantage of its reserves by recovering more coal more efficiently, said John DeMichiei, president and chief executive officer of Bull Mountain Coal Mining Inc., formerly BMP Investments Inc.
The Montana Department of Environmental Quality’s Industrial and Energy Minerals Bureau approved the mine expansion Jan. 17, about a year after the company applied for the revision. The application went through a technical analysis, an environmental assessment and public review.
The DEQ’s approval requires the company to submit a mitigation plan for potential damage to surface structures and increases the bonding amount.
DeMichiei, a former administrator with the federal agency that regulates mine safety, said he thinks the state has taken an ”ultra-conservative” approach to the expansion plan but accepts the requirements. He said he is diligently trying to work with the regulators and to build trust.
A landowner, whose ranch lies above the mine expansion area, is still concerned about potential damage to her property and springs.
”The company is saying nothing bad will happen. I have grave doubts about the truth of that,” said Ellen Pfister, whose family runs cattle south of the mine. ”I think it’s basically an experimental permit.”
The company also is seeking another major amendment to its mine plan to modify a coal-hauling railroad loop and to add new processing facilities. The DEQ determined the company’s application was complete on Jan. 18 and has started its technical review.
The mine expansion adds 2,172 acres to the existing 4,220 acres permitted, bringing the total permitted area to 6,392 acres.
The expansion also adds about 23.5 million tons of coal reserves to the existing permit area, for a total of about 39.5 million tons of coal permitted. About 26.9 million tons from those reserves are recoverable, the DEQ said.
The company estimates that it has 144 million tons of coal reserves for the first 21 years of mining, said Catherine Dreesbach, a DEQ engineer who worked on the mine expansion amendment.
Overall, the company has an estimated 340 million tons of coal reserves, DeMichiei said. ”This is the last significant reserve in the United States that is contiguous,” he said.
The mine seeks to begin longwall mining in December. At full production, it will produce 11 million tons of coal a year, DeMichiei said.
More efficient mining
The Bull Mountain mine, whose history dates to the 1880s, is Montana’s only underground coal mine. The mine extracts coal with a machine called a continuous miner, which leaves some coal as support pillars. But the company intends to switch to the more efficient longwall method.
Longwall mining uses a machine that extracts almost all of the coal from panels called longwalls. As the machine advances and removes coal, the ground above the mined-out area collapses or caves in. Surface collapsing, known as subsidence, is one of the environmental effects of longwall mining.
The initial mine plan called for longwall panels that were 800 feet wide and 10,000 feet long. The revision enlarges the panels to 1,250 feet wide by 23,000 feet long (more than four miles).
Today’s technology, DeMichiei said, allows coal to be mined more efficiently from longer and wider panels, which reduces the number of times the equipment must be moved.
Enlarging the panels causes a more uniform surface subsidence over larger areas, the DEQ said. ”From an environmental regulatory standpoint, this revision is an improvement over the previous mine plan in that surface effects would be fewer and more spread apart,” the agency said.
With the Bull Mountain expansion, the surface is expected to drop or subside as much as nearly eight feet, the agency predicted. The Mammoth coal seam, which the company now mines, ranges in thickness from eight feet to 11 feet in the permit area.
Dreesbach said about 90 percent of the subsidence occurs immediately as mining progresses. There also may be some residual subsidence over time, depending on the geology.
Because subsidence could damage communication towers on Dunn Mountain, the DEQ is requiring the company to submit a mitigation plan before April 1. The plan must be approved before longwall mining begins.
Measures also are planned to address surface and groundwater resources that may be affected within the permit area, the DEQ said. Water resources – including springs, streams and wells – are to be monitored by the company.
Water for livestock could become an issue if the aquifers that landowners use are damaged, Dreesbach said. The company would have to replace the water sources, she said. Some surface cracking is expected, and minor damage to roads and fences is possible.
State regulations also require the company to promptly repair damage to private property. While there are some buildings within the permit boundary, there are no residences, Dreesbach said.
The regulations may offer some comfort to Pfister, but she had her doubts. The area of her ranch to be undermined includes four sections in the northern portion of her property and Dunn Mountain. Pfister calls the area the ”high country.” It’s where the Pfisters depend on high-quality water from springs to pasture their cattle in the summer.
Pfister said she is worried that the mining will drain her springs and doesn’t know how the company would replace them.
A longtime member of the Northern Plains Resource Council and an activist on coal-mining issues, Pfister has visited longwall mines in the East and has seen the effects of subsidence.
”If I had a house in that area (of the Bull Mountains identified for mining), I would be desperate. What it does to structures is pretty wild,” she said. Pfister’s house is located about six miles south of the expanded mining area.
Pfister expects to have to wait until mining is complete to see what the environmental damage might be. ”If it happens, I’ll be on his (DeMichiei’s) doorstep. If it doesn’t, I’ll be happy,” she said.
A higher bond
The mine plan revision also requires a higher bond to pay for cleanup costs if, for some reason, the company becomes unable to do it.
The DEQ, DeMichiei said, allowed the company to bond in three phases. The first phase bond is $6.1 million and applies to existing disturbances at the mine, as well as to items associated with mining in the amendment area. The $6.1 million includes the current $1.5 million bond plus an additional $4.5 million.
At the company’s request, the $4.5 million will be submitted in two parts. The first amount, $1.8 million, which the company posted last month with a cash bond, will cover additional underground mining operations, including the operation of the longwall miner. The remaining $2.7 million must be posted before any disturbance within the approved waste disposal area.
The second and third phases of the bond will cover additional mine facilities and longwall mining but have not yet been determined. Those amounts will be addressed in subsequent mine plan revisions, Dreesbach said. All phases of bonding must be posted before longwall mining begins.