Massive Landslide Closes Bingham Canyon Mine

Tim Heffernan (via nc links):

Bingham is an open-pit mine—a gigantic hole in the ground. The landslide, in effect, was the collapse of one of the pit walls. (For scale, the pit is a bit less than three miles wide and a bit more than three-quarters of a mile deep, and as you can see, the collapse stretches halfway across it and all the way from top to bottom.) Kennecott Utah Copper, the subsidiary of the mining giant Rio Tinto which runs Bingham Canyon, has a spectacular Flickr set here. Check ’em out.
The landslide went off at about 9:30 in the evening on Wednesday, April 11. It was expected: like most modern mines, Bingham has redundant sensor systems (radar, laser, seismic, GPS) that measure ground movement down to the millimeter and give plenty of warning when a collapse is imminent. The mine was evacuated about 12 hours before the landslide, and nobody was hurt.
But the scale of the landslide was a surprise. Approximately 165 million tons of rock shifted, causing a highly localized earthquake measuring 5.1 Richter. It damaged or destroyed roads, power lines, and other infrastructure, and a number of the giant shovels and dump trucks that move ore and waste rock out of the pit. (For gearheads, the shovels are P&H 4100s and the trucks are Komatsu 930Es. Bingham’s fleet includes 13 of the former and 100 or so of the latter. Here’s a fun picture showing the scale of a 4100’s scoop)
The lost equipment was worth tens of millions of dollars, but much more significant is the fact that the landslide has shut Bingham Canyon down for an as-yet undetermined length of time. Much more significant because Bingham Canyon is not just another copper mine. Physically, it is the largest in the world, and it is among the most productive. Each year it supplies about 17 percent of U.S. copper consumption and 1 percent of the world’s.

Wow.