(2) In an open pit coal mine coal is being extracted on four levels. Mine cars carry the
coal to bins from which it is dumped into hoist cars. These cars transport the coal to the hoist
building, and a conveyor carries it to the railcar-loading building (Figure 2-11).
Figure 2-11. Open Pit Coal Mine.
(3) In an open pit chromium mine a round depression has been excavated in the valley
floor. To prevent flooding, a diversion dam was constructed, and a tunnel in the hillside carries the
stream around the site of the mine. The ore is dug by a power shovel and transported by rail