Revenues from recovered wastes

Table 4.5 Revenues from recovered waste materials...

The economics of some mines frequentiy depend heavily on the revenues derived from leaching the waste to recover additional copper. This waste material, which has to be removed to uncover the ore, may be hauled to specially constmeted dumps, where the sulfides, the most common form of copper mineral, are oxidized and the leach solution can contact the waste material uniformly. Economics sometimes precludes optimization of dumps for leaching operations because of such factors as compaction, size distribution, and terrain (16). 

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