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Laboratory and field treatment tests were performed to evaluate the effectiveness of lime treatment for mitigation of environmental effects of acid mine drainage (AMD) at the Sarcheshmeh porphyry copper mine. AMD associated with the rock waste dumps is contaminated with Al ([36,215 lg/L), Cd ([105 lg/L), Co ([522 lg/L), Cu ([53,250 lg/L), Mn ([42,365 lg/L), Ni ([629 lg/L), and Zn ([12,470 lg/L).The concentrations of other metals (Fe, Mo, Pb, and Se) are low or below detection limits (As, Cr, and Sb). Due to the very high Al and Mn content and the low concentration of Fe, a two-stage lime treatment method was chosen for the laboratory tests. In the first stage, the AMD was treated at four pH set points: 7.5, 8.9, 9, and 10. In the second stage, after removing the sludge at pH 9, treatment was continued at pH 10 and 11. The results indicated that a two-stage treatment method was not necessary because elements such as Al, Cu, Co, and Zn were easily treated at pH 7.5, while complete removal of Cd, Mn, and Ni only required a pH of 10. Increasing pH during the treatment process only caused a slight increase in Al. Field treatment tests support the laboratory results. Lime treatment of highly contaminated AMD from dump 11, using simple low density sludge pilot scale equipment, show that contaminant metals are treatable using this method. The mean treatment efficiency for contaminant metals was 99.4% for Al, % for Cd, 99.6% for Co, 99.7%for Cu, 98.5% for Mn, 99.7% for Ni, 99% for U, and 99.5% for Zn. The optimum pH for AMD treatment by lime was in the range of 9-10. The produced sludge in the treatment process was highly enriched in the contaminant metals, especially Cu ([7.34%), Al ([4.76%), Mn ([2.94%), and Zn ([1.25%). A correlation coefficient matrix indicates that the distribution pattern of the contaminant metals between soluble and precipitated phases is consistent with the hydrochemical behavior of the metals during the lime treatment process.

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Identifying the possible sources of potential harmful metals in groundwater systems plays a crucial role in evaluating the potential risks to residents and local plant cover. An attempt was made to define the origin of Al, Cd, Cu, Fe, Mo, Ni, and Pb in groundwater using multivariate statistic approaches [principal component analysis (PCA), hierarchical cluster analysis], and tailings sequential extraction by the method of Tessier et al. The concentrations of studied elements were measured in 42 samples collected from 15 stations surrounding and downward the tailings dam of Miduk Copper Complex, central province of Kerman, Iran. According to the PCA results, confirmed by cluster dendrogram and metal content measurement of tailings sequential extracts, two components accounting for nearly 73% of the total variance, controlled the heavy metal variability and classified the possible source of groundwater contamination into two categories: (1) upper seepage which controls the variability of Cd, Cu, Fe, Ni, and Pb and (2) toe seepage of tailings dump affecting on Mo and Al concentration in downstream groundwater.

Feasibility study using microwave-IRT sorting technique for preconcentration of oversize screen rejected ores in primary mills of concentration units of Sarcheshmeh copper complex was investigated in this study. Three size fraction samples were exposed to microwave radiation followed by thermography imaging. Temperature rise of samples were compared with their element grades as provided by XRF analysis. Sortability performance index was computed for each size fraction and cumulative mass copper recovery was plotted for them. At first, the statistical method of cluster analysis (CA) was employed to study the thermographic data. The results of this analysis, in addition to the confirmation of previous findings on the relationship between temperature rise of the samples and their content of iron and copper sulfides showed that the ratio was proportional to the grade of iron and copper sulfide. Finally, it was shown that sorting this rejected stream using MW/IRT method is feasible and beneficial.