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Arizona’s Children and the Environment

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Surface brine deposits are exploited using solar evap- oration ponds to concentrate and precipitate the potash. The evaporation ponds are extensive, with some operations covering in excess of 90 square kilo- meters of land area to produce around 8 million tonnes of potash ore per year. Conventional mechanized underground mining oper- ations are the most widely used method for the extraction of potash ore. A variety of mining tech- niques and equipment may be employed depending on factors such as: the orebody depth, geometry, thickness and consistency, the geological and geotech- nical conditions of the ore and surrounding rock, and the presence of overlying aquifers. Methods in wide- spread use include variations of room.