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Show 73 coatings of native copper, cuprite ( copper oxide), and malachite. Malachite coatings are also found on boulders at the beach and as crusts on the tailings themselves. During the tailings test of 1965- 1966, about 470 tons of tailings were placed in the Lake. Although these tailings contained only about 0.075 percent copper, streaks of sulfides ( chiefly pyrite but containing some chalcopyrite) formed, which contained up to 1.6 percent copper. As waves and currents acted on the tailings and dispersed the lighter minerals into the Lake, the overall copper content of the remaining tailings increased to 0.22 percent copper. ( Suekawa, 1970) It is probable that the malachite on the oolitic sands and boulders and the copper minerals on the nail derived from the tailings. Details of the solution of copper from the tailings and its redeposition are not fully understood and are currently under investigation. THE GREAT SALT LAKE AS AN EFFLUENT RECIPIENT Due to location, size, and quality, the Great Salt Lake has been the natural choice to receive waste water. From the time the first sewer was installed for Salt Lake City until 1965 when the first sewage treatment plant was constructed for the city, the Lake has been receiving raw sewage. The water quality of inflows has improved since 1965 and, with implementation of water quality management programs in the various tributaries, will be upgraded further. Thus, sludge accumulated at the bottom of Farmington Bay over the years has been and will be a major water quality problem although it was prevented from rapid decomposition by the hypersaline environment. The |