Characterization and Pollution Assessment of Potentially Toxic Metals (PTMs) in the Sulfide Tailings from Boudoukha Abandoned Mine (Zn-Pb-Cu), NE Algeria

The Boudoukha mining field located at the North-East of Algeria, was mainly exploited for Pb, Zn and Cu, which provided nearly 30,000 tons of concentrate containing 45-50% Zn, and 5000 tons of concentrate containing 55-75% Pb. However extraction method, treatment, and enrichment process for this type of ore have allowed release and anarchic storage of sulfide mine tailings and their waste rock, which are a potential source of pollution. For that, an environmental pollution assessment is required at this mine site, in order to identify and evaluate which potentially toxic metals (PTMs) contained in this mine tailings may present an immediate risk. Such an interdisciplinary approach is crucial to meet the environmental challenges associated with mining activities. Characterization results show that potentially toxic metals PTMs (Zn, Pb, Cu, Cd, and As) comes mainly from sulfide tailings of processed ore, while dominant silicates come from their host rocks. Static methods using multivariate PCA analysis show that the main source for these potentially toxic metals (PTMs) is the Boudoukha Ore deposit and their mining activities. Thus, acid-generating potential indicate that tailings ranging from uncertain (UC) to immediate potential acid forming (PAF) with high risk. That confirms the results obtained by using environmental geochemical indices [enrichment factor (EF) and geo-accumulation index (Igeo)], which shows enrichment degree and pollution level in PTMs in all samples, varies from severe enrichment to background values, and from strongly or very strongly to no pollution respectively. Characterization and acid-production potential of Boudoukha mine tailings.Pollution assessment of PTMs on the immediate environment.