R. Dabiri; M. Bakhshi Mazdeh; H. Mollai
Abstract
The aim of this study was to determine the extent of metal pollutions and the identification of their major sources in the vicinity of the Sangan iron mine occurring in NE Iran. Soil samples were collected from the vicinity of the mine site and analyzed for heavy metals. In addition, the chemical speciation ...
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The aim of this study was to determine the extent of metal pollutions and the identification of their major sources in the vicinity of the Sangan iron mine occurring in NE Iran. Soil samples were collected from the vicinity of the mine site and analyzed for heavy metals. In addition, the chemical speciation of these metals was investigated by means of the sequential extraction procedure. The statistical and spatial variability of the metal concentrations and other soil parameters were also analyzed by the multivariate statistical methods (principal component analysis and cluster analysis). Contaminant Factor (CF) and Enrichment Factor (EF) were used to evaluate soil pollution in the samples. By this study, one can conclude that a notable enrichment of heavy metals happened in the margin of the mining area. The data obtained reveal that soils in the area are contaminated, showing higher levels of Fe, Sn, Co, Cu, Sb, S, and Cd in comparison with their normal distributions. The results of sequential extraction analysis and multivariate (geo)statistical methods show that the variability of Fe, Sn, Co, Cu, Sb, S, and Cd is predominately controlled by the anthropogenic source (mining activity), whereas Pb, Cr, and Zn are mainly of natural (geogenic) origin.
M. Otari; R. Dabiri
Abstract
Heavy metal concentration in the soils and sediments has increased worldwide during the last century due to the mining, smelting, and industrial activities. The Forumad chromite deposit is located in the Sabzevar ophiolitic complex (SOC), with a long history of mining activities, yet very little is known ...
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Heavy metal concentration in the soils and sediments has increased worldwide during the last century due to the mining, smelting, and industrial activities. The Forumad chromite deposit is located in the Sabzevar ophiolitic complex (SOC), with a long history of mining activities, yet very little is known about the heavy metal contamination in its surrounding environment. In this research work, the soil pollution by heavy metals was investigated with respect to the geochemical, statistical, and environmental indicators over the chromite mine in Forumad. The concentrations of heavy metals were analyzed, and the results obtained showed that the mean concentrations of Cr (5837.5 ppm) and Ni (570.7 ppm) in the nearby soils and sediments were significantly high. On the other hand, the mean concentrations of the other heavy metals present such as As, Cd, Co, Cu, Pb, and V were close to the geological background values. The multivariate statistical analyses (Pearson coefficient analysis, Cluster analysis, and principal component analysis) were used to understand the various anthropogenic and geological (lithogenic) sources. Our geochemical and environmental assessments suggested that Cr, Ni, Co, and V had similar properties, and their presence in the soils was mainly from the ultramafic rocks and chromite deposits. However, the calculated enrichment factors for Cr and Ni were more than 10, suggesting their anthropogenic sources due to the mining activities. The significant Cr and Ni contaminations in the Forumad nearby soils indicated that the status of heavy metal contaminations of the area should receive further considerations in the metal mine areas throughout SOC.
