Distribution and risk assessment of toxic metal pollution in the soil and sediment around the copper mine

Background: Industrial pollution of metals is a serious environmental concern. The presence of Sarcheshmeh copper (Cu) mine and the possibility of soil pollution, were the primary motivations for evaluating heavy metals in this area. Methods: A total of 171 soil and 10 sediment samples were collected randomly from the study area for Cu, aluminum (Al), molybdenum (Mo), lead (Pb), and cadmium (Cd) determination. The USEPA method was used to acid digest soil samples, and metals present in the samples were detected using atomic absorption spectroscopy. Results: By measuring metal concentrations and calculating the geo-accumulation index (Igeo), enrichment factor (EF), and contamination factor (CF), the level of soil pollution by metals was assessed. It was found that soil and sediment samples were contaminated with Cu and the pollution decreased from the mine to Rafsanjan city, indicating that the pollution was anthropogenic. The soil has not been poisoned by Al or non-natural states because it was alkaline. Sediment samples were less than moderately polluted by Mo and Pb, but Cd and Cu were more problematic. Conclusion: Increasing the distance from the Cu mine resulted in a decrease in toxic metal concentration. The study concludes that by monitoring and filtering wastewater from the Cu mine, pollution caused by trace elements in the soil can be greatly reduced.