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Risk assessment is considered an essential tool to assist in the management and mitigation of polluted areas, especially those associated with economic activities that significantly degrade the environment, such as mining. However, most of the methodologies of risk assessment adopt the deterministic approach of using a fixed value for ascertaining the hazards derived from exposure to chemical pollutants. However, this is not the case of the Human, Ecological and Radiological Risk (HERisk) code, which allows space-time assessments of ecological, radiological, and human health risks. Indeed, this work aims to describe this new software (enhanced version of HHRISK), which not only improves the performance of the code but also increases its applicability and versatility. To showcase its usefulness in evaluating ecological pollution and human health risk were studied the contents of potentially toxic elements (Co, Cu, Fe, Mn, Ni, Pb, and Zn) in soils and surface waters from the nickel mining area in the municipality of Itagibá (Bahia, Brazil). The obtained results showed that metals are non-homogeneous distributed, suggesting the presence of local enrichment sources, mainly related to human activities. The statistical analyses carried out revealed that mining and agricultural activities are possibly responsible for the contents of these pollutants in both soils and surface waters. The calculated ecological indices of pollution confirmed anthropogenic pollution around the mining area, especially in the locations closest to sterile waste piles. The results of the human health risk assessment revealed that the ingestion of meat and contaminated water are the main routes for entering the potentially toxic elements to the human body and that Co is the chemical specie that poses the highest risk in the entire region. The hazard index (HI) values indicated that the whole area around the mine should be considered as a high risk for human health., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Mining, although relevant and indispensable for human socioeconomic development, is considered one of the most polluting anthropogenic activities. Water resources are the most vulnerable environmental compartment to the direct impacts of mining, especially in the semi-arid regions. In these regions, mining activity constitutes an important challenge in the management of water resources; since its impacts can be maximized by the adverse meteorological conditions. This study aimed to assess the level of contamination in water resources of three important mining areas in a semi-arid region, where approximately 70,000 people live. The concentrations of eleven heavy metals in sediment, surface and groundwater samples were determined by ICP OES. The results obtained for water samples indicated significant contamination by Cd, Pb, and U, based on the limits established by Brazilian and international regulatory legislation. In the case of sediment samples, higher concentrations of Cr, Cu, Ni, and V were observed. Pollution indices (PLI, CF and I geo ) revealed moderate to extreme contamination mainly along the Jacaré and Contas rivers. The Pearson correlation, Principal Component, and Hierarchical Cluster analyses were performed to identify patterns in the distribution of elements and common sources of pollution. The results suggested that the concentrations of Co, Cr, Cu, Fe, Mn, Ni, and V were mainly related to mining activities and, to a lesser extent, natural sources. In the case of Cd and Pb, contamination may have an important contribution from fertilizers use, whereas Zn has a mixed source of both lithogenic and anthropogenic origin. On the other hand, the high concentrations of U, specifically in groundwater samples, were associated with geogenic causes. Although the potential ecological risk values indicated a low ecological risk; other sediment quality indices (TEL, PEL, ΣTU, and PEL-Q) revealed that there is 25% of the probability that the content of heavy metals in water resources near the mining areas induces adverse toxic effects on aquatic organisms., (Copyright © 2020 Elsevier Ltd. All rights reserved.)