Why Is Underground Mining For Hard Rock Used?

Why Is Underground Mining For Hard Rock Used?

Mining Ventilation is primarily used for the deep deposits of the valuable minerals. The mines are quite expensive as compared to the surface mined and they typically take much longer time to generate profits. The value of ore should be large enough for making up for increased costs.

Accessing the underground ore deposits

Before the underground ore deposits may be accessed, the central excavation needs to be created. There are mainly 3 types of excavations i.e. shafts, declines and adits.

Decline is the wide spiral shape ramp which cuts into bedrock. They are cut out for allowing the heavy trucks to access to deep parts of mines. They are generally used for shallow underground mines.

Adits are the horizontal tunnels which are dug into ore bearing hills or the mountains. They are mainly used while the ores body is horizontally oriented and therefore a deep shaft is not necessary.

Techniques used for underground mining

Pillar and room mining is used for the horizontal ores bodies.

Stopping is mainly used for the vertical ore body. The hole is blasted in the ore body and desired ore is eradicated leaving an empty space known as stope.

Dangers of the underground mining

The miners could be exposed to the toxic fumes while the process of mining is done. Flammable chemicals may accumulate under the ground till they pose combustion hazard. Cave in is a huge risk irrespective of the steps that the miners take for supporting mine ceilings.