Highwall mining is a
hybrid system that extracts the coal reserves lying beyond the reach of your
conventional surface mining operations and for substantially
less
capital cost and
lead time. It consists of a
continuous miner driven by remote control, extracting the
coal and conveying it through augers or chain conveyors to the outside for stockpiling and transporting. It is typically a rectangular horizontal cut from a
highwall bench, it's depth may be as deep as 900 feet. The highwall mining system is usally adopted in the later stages of area or
contour mining. A highwall mining guidance system can be utilized to provide navigation and control of coal mining machines, a guidance system may include a
ring laser gyroscope and
gamma detector for control of the cutting horizon.