3 types of surface mining

     There are three types of surface mining. They all are on the surface. The three types of surface mining are: Contour mining, mountain top removal, and strip mining.
     contour mining is a type of strip mining that follows a hill. The advantage of counour mining is that it is less dangerous the disadvantage is that there is more erosion of the hill.
contour mining


     Mountain top removal is the next type of surface mining. The tops of hills are removed to access the coal on the inside of a mountain. The over burnden is pressed into other higher areas in the area. The disadvantages of this is that the origianal mountain is not restored after this. This is also very controversial. the advantages to mountain top removal is it is efficient.
mountiain top removal
 

     Strip mining is the final method of surface mining. It is used when coal is near the surface or the overburden is unstable. the advantage is that the dirt removed is placed in a previous cavity. the disadvantage is it is not very economically friendly.
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