Word: rocks
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Dates: during 1980-1989
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...motive for these mountainous excavations: gold. In 1961 Livermore, then working for the Newmont Mining Corp., made a seminal discovery. He looked for gold in the "windows" of a geological feature known as the Carlin Trend. Windows occur where obscuring layers of rock, displaced by an uplift, have eroded to expose the rock below. When Livermore cut into a window on the Carlin Trend, he hit what nongeologists took to calling invisible gold...
...extract gold from such low-grade deposits, miners must crush tons and tons of rock, which is piled into mammoth heaps and irrigated with cyanide. The cyanide percolates through the heap, extracting the gold. In the early days of the invisible-gold rush, a ton of ore might contain a few tenths of an ounce of gold. Today that minuscule amount would be considered high grade. Says Livermore: "They're mining deposits that we would have considered waste rock back in 1961." Nevada mines are now digging up a ton of rock to get back as little...
About a dozen large open-pit gold mines using such techniques are now strung out along the Carlin Trend. The Dee. Maggie Creek. Gold Quarry. Goldstrike. Blue Star. The Rain. The Bootstrap. American Barrick Resources Corp., a Canadian company, recently announced plans to excavate a billion tons of rock to get at 12 million oz. of gold -- worth about $4.4 billion at current prices. In the process, the mine will bequeath to posterity a hole 1,500 ft. deep, 4,000 ft. wide and 7,000 ft. long...
...down by U.S. Forest Service land in the Independence Mountains. Until gold was discovered, the Van Normans owned the rights to graze their cattle there. Now, on the very fence they built to control their herd, the Freeport-McMoRan Gold Co. has posted a big KEEP OUT sign. Waste rock from the mining operation has begun pushing toward the canyon like a moraine advancing at the prow of a glacier...
...This summer the state legislature passed the first mining-reclamation bill in its history. Already the more progressive companies have embarked on efforts to ameliorate the eyesores their mining operations have created. The Pinson Mine on the Getchell Trend, in which Livermore has an interest, is actively transforming waste-rock dumps into gently rolling hills planted with sagebrush, bitterbrush and crested wheat. Freeport-McMoRan, for its part, has hired a wildlife biologist to take charge of its reclamation activities. It has laid ambitious plans to hide its footprints by recontouring and reseeding old exploration roads, waste dumps and leaching heaps...