Word: open-pit
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...Pollution fouled streams and scarred mountainsides. By the mid-1940s, Butte's high-grade ore thinned out, forcing the company to increasingly undermine the town in its search for copper. By 1955, when the decreasing quality of the ore made even those operations uneconomical, Anaconda turned to cheaper open-pit mining...
...Open-pit mining methods, like those used to get copper in Butte, Mont., may also be tested, probably at one of the Colorado tracts. Great earth-moving machines would first peel back the sagebrush and grass over thousands of acres, next remove billions of tons of earth and rock, and finally gouge out the oil-shale beds 100 ft. to 850 ft. below the surface. The other technique, to be tried at the remaining leaseholds, will be to deep-mine with conventional pillar-and-room tunneling, as is done with coal-but on a gargantuan scale. More than...
There once was a time, about 20 years ago, when Reserve Mining's plant was considered a blessing. Northern Minnesota, its Mesabi Range depleted of rich iron ore by a half-century of open-pit mining, teetered on the brink of economic collapse. Then engineers devised a method of extracting iron from crushed taconite, a flintlike rock that contains some 25% iron. Reserve Mining, which is owned by Armco and Republic Steel, easily obtained dumping permits on the assumption that the gray torrent of taconite would sink 900 feet to the bottom of the lake's "Great Trough...
...problems that Allende's government is having with falling production, rising absenteeism and soaring wage demands at Chile's newly nationalized mines, Castro vigorously railed against troublemaking "demagogues" and "reactionaries" during a speech at a mine in Pedro de Valdivia. At Chuquicamata, the world's largest open-pit copper operation, he launched into a lecture on productivity. He thundered that "a hundred tons less per day means a loss of $36 mil lion a year...
...that period," complained Kennecott President Frank Milliken, whose firm has been a particularly good corporate citizen in Chile. Said Anaconda President John Place: "Allende's accounting theory is nothing more than a thin pretext for confiscation. He's now contrived to grab the world's biggest open-pit copper mine [Anaconda's Chuquicamata], plus a second major underground mine, and not pay a dime...