Assessment of Soil Physicochemical Characteristics and As, Cu, Pb and Zn Contamination in Non-Active Mines at the Portuguese Sector of the Iberian Pyrite Belt

This study aimed to evaluate soil physicochemical characteristics (pH, electrical conductivity, organic matter, total N, and extractable P K), potentially toxic elements (As, Cu, Pb, Zn), in non-active mines located the Portuguese sector of Iberian Pyrite Belt (IPB). A 70 sampling sites were surveyed at Aljustrel Lousal, areas already rehabilitated, São Domingos, where rehabilitation was only beginning. The soils Domingos very heterogeneous, with extreme values for some properties (e.g., minimum pH 2.0 maximum As concentration, 4382.8 mg kg?1 dry weight basis (DW)). site that presented a higher As, Zn concentration (median values: 441.5, 545.9, 1396.8, 316.5 DW, respectively), above quality guidelines proposed by Environmental Agency (18, 230, 120, 340 respectively). principal component analysis identified most relevant explain data variance, which Pb followed Cu concentrations, allowing separation from other mines. Pearson correlation coefficients revealed strong associations between markedly found concentrations whereas had an elevated but also Zn. It is evident risk persists mine area, not alleviated “dig, dump, cover” techniques implemented rehabilitate area.