Overburden

Common card · No. 277151

In mining, overburden (also called waste or spoil) is the material that lies above an area that lends itself to economical exploitation, such as the rock, soil, and ecosystem that lies above a coal seam or ore body. Overburden is distinct from tailings, the material that remains after economically valuable components have been extracted from the generally finely milled ore. Overburden is removed during surface mining, but is typically not contaminated with toxic components. Overburden may also be used to restore an exhausted mining site during reclamation. In some cases overburden can leach toxic materials into the environment. Interburden is material that lies between two areas of economic interest, such as the material separating coal seams within strata.

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