Posted on 04/22/2013 12:52:47 PM PDT by dirtboy
For the past few months I’ve been reporting a big story on the copper industry for Pacific Standard. It takes a broad look at how the global economic boom of the past decade, led by China and India, is pushing copper mining into new regions and new enormities of investment and excavation. (It’ll be out in June.) But a few days ago a very local event shook the copper industry, and I thought it would be neat to look at how a crisis at a single mine can ripple through space and time, ultimately affecting just about everyone around the globe.
Above is a picture, from local news channel KSL, of a massive landslide at Bingham Canyon Mine, about 20 miles southwest of Salt Lake City.
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.) KSL has more pictures here, and 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.
(Excerpt) Read more at boingboing.net ...
They got greedy and failed to remove overburden resulting in unstable slopes and eventual failure. As far as the price of copper is concerned, that pit is a shadow of its former output when it was high grade low hanging fruit, and realistically shouldn’t affect copper prices or availability (in a world without speculators).
The guy with the corner office of that building had a great view!!
LMAO!
LOL that’s not the only ass backward thing I said. The big open pit mines in Michigan are iron mines.
Ya, they’ll be whistling while they work, too! That will be one dangerous endeavor!
Pictures in the link at Post 8.
Tailings are not the same as the removed overburden.
IT’s super-easy to find on Google Earth. The building right next to the flow of dirt is a truck maintenance building, and there was another building with lots of tires lined up that was wiped out.
Boy O Boy....I’m suprised no-one was killed.
This Utah USA mine is owned by Rio Tinto, which is British, aren't they? Or have they subcontracted operation to a Chinese company?
The copper mining company was aware of the impending slide and had warned residents near the mine Wednesday that a slide was possible any day. Kennecott engineers had been detecting ground movement as far back as February.
At the time, the movement amounted to just fractions of an inch, but it was enough for the company to close and relocate the mine’s visitors center. The visitors center will not open in 2013, the company announced Thursday.
“This is something that we had anticipated,” Bennett said of the slide. “We knew the slide was imminent. We had relocated machinery, we had rerouted roads, we had rerouted utilities, we had rerouted buildings.”
Over the past few days, engineers started seeing movement of up to 2 inches per day.
“We’ve seen acceleration rates increase until where we landed (Wednesday night),” Bennett said. “When it reaches 2 inches per day, that’s certainly a time when we want to take steps that we have been planning for a number of weeks in order to make sure people are out of the way.”
Wherever the removed overburden is, it would make a much bigger pile than that; look at its size relative to that of the pit.
I have been to a few mines of this nature. The walls of the pit are cut back in “benched” terrace excavation cuts to allow travel along the terraces as the back the cut wider and wider.
The underlying earth strata doesn’t always stay in place if ground water or other factors change. The banks of the entire pit have given way. The waste or tailings are placed elsewhere, not above the banks of the excavation as the overburden weight would be massive.
The earth strata is made up of layers or rock, shale, clays, silts and other materials. Generally they engineer what “angle of repose” is natural within the strata and design the benching to be as flat as the natural angle of repose for the native rock and soils. Sometimes they make a big error or the unanticipated happens.
Those photos clearly show that the weight of uncompacted overburden was more than the lip could bear and the piled up dirt was dumped down the side.
Lesson...... don’t pile the dirt too close to the edge of the hole
Rio Tinto supplies around 18 per cent of US annual refined copper requirements from the Bingham Canyon mine in Utah.
http://www.riotinto.com/documents/ReportsPublications/corpPub_Copper.pdf
Call Stephen King.
“Tak” has escaped.
I think you are right and I am wrong. I cannot find anything that clearly maps it out. I played around on the 3D in Google Earth and that likely was a “mountain” that had been “edged” but I could be wrong.
What is a nice view without answering the question is this:
http://www.3d-exposure.com/panos1/copper-mine-1.html
That pic looks like a painting. The color and lighting in it, in addition to the subject matter, makes it an interesting landscape.
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