Surface coal mining

Strip mining

Strip mining is a method used when coal is near the surface or when the surface is too unstable to mine under. As the mining progresses, the overburden is placed in previous mining cavities.

Contour mining

Contour mining follows the contour of a hill, leaving terraces in the mountainside.

Mountaintop removal

Mountaintop removal removes the tops of hills to access horizontal coal seams. Overburden is pushed to areas between high elevations and the original contour is not restored. This is the most controversial method of coal mining.

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