Since 1864, coal has been produced in a total of 29 Colorado counties. Currently it is produced in nine counties: Delta, Garfield, Gunnison, La Plata, Moffat, Montrose, Rio Blanco, and Routt counties. Coal production fell mid-century, as it was replaced by natural gas for heating and diesel fuel for locomotives. The 1960s was a time when natural gas was new and surpassed home use of coal for hot water, heating and cooking. In 1971, Colorado coal mines produced only 5.3 million tons of coal.

By 1975, overall electricity consumption began to increase and Colorado coal production increased substantially to meet demand. Production rebounded in the mid-1970s, driven by high-grade coal recovered from large new mines in northwestern Colorado and by the increasing demand for power-plant fuel.

The Clean Air Act of 1990 limited how much sulfur dioxide power plants could emit, so high sulfur coal from eastern U.S. states was blended with cleaner low sulfur coal from Wyoming, Utah, Colorado, and New Mexico. This resulted in a large increase in Colorado coal production. By 1997, Colorado coal production was more than five times as much as 1971-27.4 million tons. Mines in Routt, Moffat, and Gunnison counties accounted for more than two-thirds of this total. Annual coal production peaked in 2004 with nearly 40 million tons produced.

Since then almost all power plants in the eastern US that use Colorado coal have achieved SO2 and NO2 compliance, and Colorado’s coal production has decreased to around 25 million tons per year. See the Statistics tab for list of coal production by mine in 2010.

Colorado coal production in tons

More modern- and larger mining equipment has boosted production. During 1996, the underground Twentymile Mine used its new longwall mining system, illustrated below. This system contains three-mile-long panels, the longest in the world, to establish the current world record for one month’s coal production — just over 1 million tons. The Colowyo Mine, a surface mine, uses equipment which is among the largest in the state: a dragline bucket that holds 60 cubic yards, 240-ton trucks, and loaders with buckets that hold 35 cubic yards. The overall productivity of Colorado mines was 7.3 tons per worker-hour in 1996, compared with about 0.7 tons per worker-hour 40 years ago. This level of productivity ranked sixth out of 27 coal-producing states — a real feather in Colorado’s cap. Most Colorado coal comes from underground mines, which nationally tend to have lower production rates. Colorado’s efficient operations largely compensate for mining under more difficult conditions.

  • 2009 Colorado coal production:
  • Total coal production(federal, state, and fee):28.5 million tons
  • Federal coal production:17.7 million tons
  • Federal coal royalty:$44 million

Diagram of an underground mining method called longwall mining used at 5 mines in Colorado.

2012 Colorado coal production by county:

Underground Surface Total
Coal-ProducingState & County Number of Mines Production* Number of Mines Production* Number of Mines Production*
Delta 1 3,430 1 3,430
Gunnison 2 9,810 2 9,810
La Plata 1 639 1 639
Las Animas 2 69 2 69
Moffat 2 4,567 2 4,567
Montrose 1 353 1 353
Rio Blanco 1 1,673 1 1,673
Routt 2 8,024 2 8,024

*Thousand short tons

National statistics:

  • The USA produces 1.1 billion tons of coal each year – second only to China.
  • US coal deposits contain more energy than all of the world’s oil reserves.
  • Coal generates nearly half of all electricity in the USA.
  • Over 2 million acres of coal mined lands have been reclaimed in the last 25 years.