Strip Mining

Bucket-Wheel Excavator

This is the largest digging machine (or trencher or rotating shovel) in the world. It was built by Krupp and is shown here crossing a road in Germany on the way to its destination, an open air coal mine. Although at the mine the treads are unnecessary, it was cheaper to make the machine self-propelled than to try and move it with conventional hauling equipment. Some facts:

The machine is 95 meters high and 215 meters long (almost 2.5 football fields in length)
Weight is 45,500 tons (that's equivalent to a bumper to bumper line of jeeps 80 miles long)
It costs of $100 million
It takes five people to operate it
Maximum digging speed is 10 meters per minute
Can move more than 76,000 cubic meters of coal, rock, and earth per day

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Toquepala Copper Mine, Southern Peru

The rugged, mineral-rich Andes support some of the world’s biggest mines (gold, silver, copper, and more). This image looks down the bull’s-eye of Peru’s Toquepala copper mine, a steep sided and stepped open-pit mine. Mid-afternoon sunlight on the arid slopes of the central Andes mountains provides an accent to the mine contours. At the surface the open pit is 6.5 km across and it descends more than 3000 m into the earth. A dark line on the wall of the pit is the main access road to the bottom. Spoil dumps of material mined from the pit are arranged in tiers along the right (northwest) lip of the pit. Numerous angular leaching fields appear lower left, and the railroad to the coast is a line that exits the image upper left. The railroad was built to export Toquepala’s copper and connects the coastal port of Ilo, 95 km to the southwest.

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