Discuss Two Methods of Mineral Extraction ??
Answers
There are two basic types of extraction: surface and sub-surface (deep), each relying on a variety of techniques. Regardless of process, U.S. legislation requires operators to submit a plan for restoring the land and mitigating acid mine drainage before a permit is granted for mining operations. It further specifies that all sites be restored to their original contours and provides a funding mechanism for helping restore abandoned mines.
Underground Mining:-
When minerals are located deep within the ground, there are a variety of underground mining methods that can be utilized for excavation. The method is based primarily on whether the mineral is soft rock (i.e., coal) or hard rock (often those containing hard metals like copper or lead), and is often site specific—taking geologic, economic, and safety factors into consideration.
Surface Mining:-
Surface mining is undertaken when the minerals are located near the surface of the Earth. As opposed to underground mining in which the overlying rock and soil are left primarily intact and tunnels are dug, surface mining involves removing the top soil, called the overburden, in order to recover the minerals. The three most common types of surface mining are open-pit mining, strip mining, and quarrying.