Coal mining: comprehension questions 

1.- The differences betwen surface and underground mining are: Underground mining is used deeper than 125 feet while surface mining is used when it´s lower than 125.

2.- In surface mining, you use the following machines: Dragline, conveyor, trucks, explosives and Drills.

3.- On underground mining the tunnels are used for transportation, air circulation and support for he mine.

4.- The conveyor belts transport the coal to trucks or to storage rooms.

5.- the three types of underground mines are:

A.- slope mine: In a slope mine a tunnel slants down from the surface to the coal seam.
B.- Drift mine: a drift mine is built when the coal seam lies in the side of a hill or a mountain
C.-Shaft mine: a large hole is drilled down into the ground until it reaches the coal seam.

Glossary

1.- Dragline:  a large machine used in the surface mining process to remove overburden, or layers of earth and rock, coering a coal seam.

2.- conveyor: a continuous moving belt that transports large volumes of material.

3.-  Reclamation The process of restoring a surface mine sit to it´s original contour, function, and appearance, thus " reclaiming" it.