By contrast, underground mining produces minimal waste. But it’s more costly because the equipment is much smaller than the equipment used in, for example, open-pit mining. Usually, however, the quality of the mined ore offsets these costs.
The dangers of underground mining means access is very limited compared to surface mining operations, resulting in lower productivity.
Key fact: In terms of tons produced per worker per shift, underground mining productivity can be 5-50 times lower than surface mining
There are several techniques used in underground mining. Room-and-pillar mining, for example, is used for mining coal, and involves making horizontal drifts between large square pillars, which support the roof overburden.
Meanwhile, narrow vein stoping is used to mine platinum, and is carried out along an underground excavation’s geological veins, which contain crystallised minerals.
The final technique is large-scale mining, which can be further subdivided into long-wall mining, sub-level caving, and block caving. These are all used to mine coal, diamonds, and copper.
Benefits
Less waste
High quality ore
Economically recovers deep mineral deposits
