Underground Coal Mining

Drift mining

 Drift mining is a method of mining where coal seams intersect the surface; the mine enters the seam at a horizontal direction following the coal.

Shaft mining

Shaft mining is one of the most common methods of mining. Elevators provide access to the mines that are deep underground. Most shaft mines in West Virginia are 1000+ feet below the surface.

Room & Pillar mining

Room and pillar mining is a less effective method of mining coal. Half the coal is left behind to create pillars that support the mine roof; pillars can squeeze, thus putting pressure on other pillars and causing the roof to collapse. Roof falls are a constant danger in these mines.

Continuous mining

Continuous mining utilizes machines with drift and room and pillar mines. One miner can operate a continuous machine with a rotating steel drum with tungsten carbide teeth to mine five feet of coal per minute. This method has been used since 1940 and is often combined with a conveyor system.

Longwall mining

Longwall mining is highly efficient. Machines support the roof of the mine with hydraulics as it is mined. Once the coal is removed, the machine retreats, allowing the roof to call behind it. This method mines more coal than the room and pillar method.

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