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Why must topsoil and overburden be removed before open-pit tar sand mining?
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heavy oil and tar sand
Major oil fields of the Arabian-Iranian basin region.
In open-pit mining, topsoil and overburden must be removed to access the tar sand deposits located beneath the surface.1
The process involves using heavy earth-moving equipment to strip and stockpile the topsoil and to remove and dispose of the overburdenāthe layer of rock, soil, and vegetation covering the resourceāso that the underlying ore can be excavated. This removal is a necessary operational step to reach the bitumen-bearing sands, which are then transported to a mill for processing and separation.1