Known shipments of steam coal from eastern Kentucky to power plants within the United States decreased by 34 percent in 2015, from 24.8 to 17.4 million tons. The largest markets for eastern Kentucky coal are traditionally located in the southeast and were led by South Carolina, North Carolina, and Virginia during the year. Overall, coal mined in the region was shipped to 15 different states in 2015. Total Kentucky coal deliveries have decreased by an average of 8.9 million tons, or by 14 percent every year since 2005, primarily because of reduced shipments from eastern Kentucky. The Winyah power plant in South Carolina was the single largest consumer of coal from eastern Kentucky in 2015, receiving 1.9 million tons. The Commonwealth’s largest consumer of eastern Kentucky coal in 2015 was the Big Sandy power plant, which has retired its coal burning unit as of May 2015.

Given the accessibility of river ports in western Kentucky, half of the region’s coal was distributed via barges in 2014. Just under a third of western Kentucky coal was transported by rail during the same year, and 19 percent was delivered by truck. In 2014, electric power plants represented 99 percent of the demand for western Kentucky coal. Kentucky exported 605 thousand tons of coal to three countries in 2015, down 35.6 percent from 2014. The federally available data are complicated by the confusion of export terminals and mining areas. For example, California is ranked tenth above in bituminous coal exports, yet produces no coal.

There are two Class 1 railroads, one regional railroad, and two short line railroads that operate totally in Kentucky or originate coal in Kentucky. The vast majority of coal shipped from eastern Kentucky in 2014 was delivered to electric power plants in the United States. Industrial facilities were the next largest consumer of eastern Kentucky coal 16.8 percent of demand for the commodity. Coke plant deliveries reached nearly one million tons in 2014. Demand from commercial consumers accounted for one percent of eastern Kentucky coal distribution during the year. Of the coal deliveries originating in Eastern Kentucky, 81 percent were distributed via rail car. The remaining loads were carried by river barge or truck.

The annual distribution of coal mined in Kentucky is a combination of instate consumers, out of state power plants, factories, and foreign exports. Demand from out of state consumers has consistently been the largest component of Kentucky coal deliveries for several decades. Eastern Kentucky coal has predominantly been sold to states in the southeastern United States. Conversely, western Kentucky coal has mostly been mined for instate consumption. Kentucky remains the single largest consumer of Kentucky coal. As other states have decreased their consumption of coal from the Commonwealth, the percentage of Kentucky coal consumed in the state has increased. Known foreign exports of Kentucky coal in 2015 were 605 thousand tons or 1.0 percent of known coal deliveries.

Longwall mining is used most efficiently in uniform coal seams (medium height 40 to 60 inches). As in the room–and-pillar method, longwall mining starts with sets of entries cut into the panel areas. The difference in the technique lies in the distance between these sets of entries and the method used to extract intervening coal. Longwall blocks range from 300 to 600 feet wide and are sometimes a mile long. The longwall machine laterally shears or plows coal from the entire face. Then the longwall machine will transport the fallen coal by an advancing conveyor to a secondary haulage conveyor. This reverses direction at the end of a cut and supports the roof around the face by a self-advancing system of hydraulic jacks. Over 80% of the entire coal face can be removed with this method. The roof is allowed to cave-in behind the advancing work areas, and the roof is occasionally blasted to ensure a controlled cave-in rate and to reduce overburden pressure on the coal being mined. The shortwall method of mining coal is best described as a process like longwall mining with two exceptions. One being the blocks of panels are smaller, usually ranging from 100 to 150 feet wide and 300 feet long. The second one being the coal is cut with a continuous miner and is loaded into shuttle cars.

Underground mining is more challenging and requires more miners, but some of the best coal is underground. Underground mining is used when the coal is buried several hundred feet or more below the surface. Some mines can extend to depths of more than 1,000 feet. Miners use heavy machinery to cut out the coal and rely on conveyor systems to transport the coal to the surface. Some underground mines require elevator shafts to move miners and coal to and from the surface. Mining has become much safer and more efficient over the years. Underground mine operations accounted for 69 percent of coal production in Kentucky in 2015, with room and pillar systems being the most common mining method. Throughout most of history, underground mines have provided most employment and coal production in the Commonwealth. During 2015, combined coal production from underground operations and surface operations was more than 61 million tons with a slight majority of production in western Kentucky

A bench is created from the removal of overburden material and coal from the surface of the perimeter of a coal seam, and the machines are generally operated from it. Previously augered areas and trench mining can also be used with a highwall miner. When the highwall miner is operated off a bench, a minimum bench width of forty-two feet is required, with fifty-five feet or more being ideal. The highwall miner is capable of mining coal seams from thirty inches to sixteen feet in thickness and depths up to one thousand feet. The highwall miner mines this range of coal seam heights because of its fitting interchangeable cutterhead modules. A highwall miner has low, medium, or high seam mining ability.

FAQs Archive - Coal Sales Online

Q: ROOM-AND-PILLAR MINING

Room-and-pillar mining has been used in the United States longer than any other underground method. Mining is accomplished by driving entries off the panel entries. As mining advances, rooms are excavated in the coal seam, the mountain above the seam is supported by pillars of coal left in place. After a block panel or section has been mined, part of the coal in the pillars can be recovered as a retreat is made toward the main entry. Around 1950, continuous mining using electric-powered machines to bore, dig, or rip the coal from the working face has largely replaced conventional mining. Conventional mining involved undercutting, drilling, placing explosives, and blasting to extract the coal. Coal is either loaded directly into shuttle cars by the machine or in a separate operation. Continuous mining is interrupted by stops to support the roof, waiting of shuttle cars, advance power and water supplies, and service the equipment.

Q: THE DIFFERENT TYPES OF UNDERGROUND MINING

Access to coal deposits for underground mines is provided by drift mining. Drift mining cuts horizontally into a hill. Slope mining is cut at an angle from the valley bottom into the hill where the coal is located. Shaft mining is cut straight down deep into the surface by way of a vertical shaft with an elevator to reach the coal seam. In underground mining, after the initial development has gained access to the coal, one of three methods are commonly used to extract the coal. Room-and-pillar, longwall, or shortwall.

Q: MOUNTAINTOP REMOVAL MINING

Mountaintop mining, often referred as mountaintop mining or valley fills, is a form of surface mining that involves an extreme topographic change to the summit or summit ridge of a mountain. It is most closely associated with coal mining in the Appalachian Mountains, located in the eastern United States. The process involves the removal up to 1,000 vertical feet of overburden to expose underlying coal seams. The overburden is often scraped into the adjacent drainage valleys in what is called a valley fill. Because of its destructive nature, Mountaintop mining is controversial and is protested by environmentalists, local residents, and others. Controversy over the practice stems from both the extreme topographical and ecological changes that the mining site undergoes, as well as from the storage of waste material generated from the mining and processing of the coal.