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Surface mining

Surface mining is a type of mining used to extract deposits of mineral resources that are close to the surface. In surface mining, heavy equipment, such as earthmovers, first remove the overburden (the soil and rock above the deposit). Next, huge machines such as drag line excavators extract the mineral. Surface mining generally leaves large devastated areas called spoil banks unless the land is recovered and it has a huge negative effect on the local ecosystem and the environment.

Types of surface mining are:

  • Open-pit mining, usually called quarrying, and generally used to extract stone and gravel.
  • Dredging, often used to bring up underwater mineral deposits
  • Area strip mining, used on fairly flat terrain, to extract deposits over a large area
  • Contour strip mining, usually used in hilly terrain, involves cutting terraces in mountainsides following the contour of the land
  • Mountaintop removal, a method that is especially devastating to the environment

01-04-2007 01:16:19
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