Open PIT & Open CAST Mining??

Open PIT & open CAST mining

Open pit or open cast mining is usually employed to exploit a near surface deposit or one that has a low stripping ratio* it often necessitate a large capital investment but generally result in high productivity , low operating cost and good safety conditions.

"Benches are created in a series to reach and exploit COAL(click here) by removing overburden."

• Open PIT Mining :

[1] Overburden is removed and dumped outside of pit [external dumping] and reclaimed later.

[2] Dumping cost higher.

• Open CAST Mining :

[1] Overburden removed is dumped inside the pit [Internal dumping] at already exploited area.

[2] Here simultaneous exploitation of coal and backfilling of void area is carried out.

[3] Dumping cost less.

[4] Work hazard to miner due to unstable overburden dump inside the pit.

*Stripping Ratio (waste/ore)- its the ratio of Volume of Overburden Handled(m³) to Amount of ore produced (tn).