While underground mining requires an array of resources, equipment and financial backing, the method is best suited if the environment and coal potential harmonize. Longwall mining accounts for 50 percent of coal mines in the world and is much safer than other methods of coal mining.
Longwall mining is a highly productive underground coal mining technique. Longwall mining machines consist of multiple coal shearers mounted on a series of selfadvancing hydraulic ceiling supports. The entire process is mechanized. Longwall mining machines are about 800 feet (240 meters) in width and 5 to 10 feet ( to 3 meters) tall.