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This study used integrated geochemical, and ionic ratios, to investigate hydrogeochemical aspects, quality, and possible contamination due to mining activities in Wadi Asal and Wadi Queih, Red Sea, Egypt. Five groundwater samples were gathered from Middle Miocene, Duwi Formation, and Nubian aquifers. The dominant ions are: Ca2+ > Na+ > Mg2+/Cl– > > for Duwi aquifer, while Asal and Nubian aquifers have Na+ > Ca2+ > Mg2+/Cl– > > . The hydrochemical facies for Duwi aquifer plot in Ca–Na–Cl–SO4 field (40%), and Asal and Nubian aquifers in Wadi Queih (60%) plot in Na–Ca–Cl–SO4 field. The heavy metal contents are as follows: Zn > Pb > Cr > Ni > Cd > Cu for Asal and Pb > Cr > Zn > Ni > Cd > Cu for Queih; all related to mining activities of Pb–Zn and phosphates. Drinking water quality index (DWQI) reveal that all the groundwater samples are improper for drinking. Irrigation water quality index (IWQI) reveal that all groundwater demonstrating a medium quality class for irrigation purposes. Groundwater exploration combined with suitable remediation techniques is recommended for future sustainable development in the investigated zone and similar coastal areas in Egypt. [ABSTRACT FROM AUTHOR]

Potential toxic elements emanating from extracted ores during gold processing present occupational and unintentional health hazards in communities, the general populace, and the environment. This study investigated the concentrations and potential health effects of metal content in the topsoils of Obuasi municipality, which has been mined for gold over the past century. Surface topsoil samples, sieved to 250 µm, were initially scanned for metals using x-ray fluorescence techniques, followed by confirmation via ICP-MS. In vitro bioaccessibility assays were conducted using standard methods. The geoaccumulation indices (Igeo) indicate high enrichment of As (Igeo = 6.28) and Cd (Igeo = 3.80) in the soils, especially in the eastern part of the municipality where illegal artisanal mining is prevalent. Additionally, the southern corridor, situated near a gold mine, exhibited significant levels of As and Mn. Results obtained for the total metal concentrations and contamination indices confirmed the elevation of the studied potential toxic elements in the Obuasi community. A hazard index value of 4.42 and 3.30 among children and adults, respectively, indicates that indigens, especially children, are susceptible to non-cancer health effects. [ABSTRACT FROM AUTHOR]

Mining operations have been a significant source of environmental pollution due to their excessive water usage during ore processing and the subsequent discharge of tailings into the environment. It is imperative to assess the extent of toxic metal release resulting from these activities at any given time. In this investigation, we explore the environmental risks and the release patterns of zinc (Zn) from zinc leach residues (ZLRs) originating from the Angoran mine in the Zanjan province of Iran. A series of batch experiments were conducted on two distinct ZLR samples (S1 and S2) to analyze the influence of factors such as particle size, contact duration, liquid-to-solid ratio, and pH of the leach solution on the leaching behavior of Zn. The primary constituents in the ZLR samples were found to be SiO2 and CaSO4. It was observed that the release of Zn was contingent on pH, with increased acidity leading to higher Zn release. Even after 360 min of contact, equilibrium was not achieved, and the release exhibited an upward trajectory. Heterogeneous behavior was noted in the particle size distribution, with the greatest Zn release observed in particles within the 0.3–0.5 mm size range. The solubility of Zn was identified as the dominant factor influencing its release from the residues, raising environmental concerns as a significant portion of Zn is present in a soluble fraction. Based on the mobility index and leaching limits defined in Decision 2003/33/EC, the tested ZLR samples were classified as highly hazardous. [ABSTRACT FROM AUTHOR]

On February 22, 2023, a devastating landslide occurred on the mining slope of an open-pit coal mine in Inner Mongolia, China, leading to the mining area being buried and 53 fatalities. The source area of the landslide measured approximately 500 m in both length and width, with an estimated volume of the deposited material reaching approximately 5 million cubic metres. Based on the severe impact of this incident, our study conducted preliminary research using a combination of methodologies, including particle image analysis, synthetic aperture radar interferometry, interpretation of optical remote sensing data, and post-event news reports analysis. The results indicated that the landslide lasted 23 s from initiation to cessation of movement. The historical deformation indicated that prior to the resumption of the mining activities, only localized deformation was observed at the rear edge of the landslide. However, when mining activities resumed in April 2021 and extended to the vicinity of the north slope, the deformation range and rate in the source area of the landslide rapidly increased. The investigation deduced that the soft foundation at the slope bottom and mining activities are the primary causative factors of this event. Mining activities, which stripped coal seams within the slope and surface rock masses, led to the expansion of tension cracks within the landslide body, weakening resisting forces at the leading edge and thus playing a significant role in destabilizing the landslide body. The evolution of the landslide from incubation to instability could be divided into four stages: early microcrack development, slow creep, accelerated deformation after resumption of mining, and ultimate instability. Therefore, it is of great significance to advance real-time deformation monitoring and early warning systems specifically those designed for mining slope areas by comprehensive measures. Furthermore, enhancing the high-frequency monitoring capabilities of synthetic aperture radar satellites is crucial to reducing the occurrence of these catastrophic events. [ABSTRACT FROM AUTHOR]

This research is focused on the assessment of the pollution status of river and lake sediments near Pb, Zn, and Cu mines and tailings in the southeastern part of Serbia—Krajište area. The study is based on hypothesis that investigated rivers and lakes in the Krajište area could be polluted by potentially toxic elements (PTEs) and that these elements could pose considerable ecological risk to the studied surface water environment. High PTE contents are detected in studied river sediments (up to 7892 mg kg−1 for Zn, 3224 mg kg−1 for Cu, 36,790 mg kg−1 for Pb, 64.2 mg kg−1 for Cd, and 1444 mg kg−1 for As). Given that the contents of the studied elements in most of the river sediments exceeded the background values, values prescribed by regulations of the Republic of Serbia, as well as probable effect concentration (PEL), it is possible to conclude that sediments were heavily polluted and that detrimental effects can be expected. Contamination indices including the enrichment factor (EF), contamination factor (CF), index of geoaccumulation (Igeo), potential ecological risk index (Eri), ecological risk index (RI), pollution load index (PLI), and aggregative toxicity index (ATI) were used to assess the degree of pollution by PTEs. The ecological risk assessment revealed that there is a significant risk observed for toxic elements (primarily Pb, Cu, Cd, and As) at this moment. The highest contamination indices (EF, Igeo, CF, PLI, and ATI) are mainly associated with historical and current mining activities. The Monte Carlo analysis based on the risk assessment indices was used to evaluate the uncertainty. The most pronounced toxic risk is found for the Pb, Cu, Cd, and As which assessment was in the range of high and extremely high-risk probabilities. The obtained results suggest that levels of toxic elements pose a significant ecological risk to the surface water environment near Pb, Zn, and Cu mines in the Krajište area. The methodology applied in this paper could be very useful for other researchers dealing with the problem of environmental pollution by toxic elements. [ABSTRACT FROM AUTHOR]

Globally, the environmental contamination of stream sediments due to geogenic and anthropogenic sources is of growing concern. In this study, the heavy metals (Cd, Co, Cr, Cu, Ni, Pb, and Zn) in 22 superficial sediments in Wadi Asal, Red Sea, Egypt, were explored to assess sediment sources, the mobility of chemical species, and the degree of contamination in sediments. Therefore, the total heavy metal values in the fine fraction (< 63 μm), a five-step sequential extraction on selective samples, risk assessment, and principal component analysis (PCA) were applied. The mobility of heavy metals in Wadi Asal sediments, according to non-residual fraction percent, declines in the following order: Cd (90.9%) > Pb (85.2%) > Co (84.4%) > Cu (80.8%) > Zn (75.9%) > Ni (48.4%) > Cr (39.6%); indicating the high mobility of Cd, Zn, Pb, Cu, and Co. The mean metal contamination factor (CF) order is Cd (10.96) > Ni (3.91) > Cr (2.77) > Zn (2.18) > Pb (2.10) > Co (1.12) > Cu (0.70). The Geo-accumulation Index (Igeo) is decreased in the following order: Cd (2.19) > Ni (0.78) > Cr (0.55) > Zn (0.44) > Pb (0.42) > Co (0.22) > Cu (0.14). The risk assessment code (RAC) revealed very high to high risk for Cd, Co, and Pb. The results pointed out that the metals Cr, Co, Cu, and Ni are from geogenic sources, while Zn, Cd, and Pb are from anthropogenic sources due to Pb–Zn mining activities. Based on the threshold effect level (TEL), Cd, Cr, Ni, and Pb have adverse effects on living organisms. According to these findings, the area along Wadi Asal and the downstream regions on the beach are highly polluted and heavy metal monitoring in sediments and aquatic organisms is recommended. [ABSTRACT FROM AUTHOR]

Maps of potential biodiversity are prominent tools for regional conservation planning because they allow to quantify the diversity of species that potentially inhabit different habitats. These maps are constructed from modeling species ecological niches based on the association between the geographical localities where species were detected and the environmental variables at those localities. Previous researches addressed the development of MPB for administrative regions using regional species distributions data to modeling ecological niches, which may lead to flawed predictions on potential biodiversity. Our aim is to assess the consequences of failing to include all available records on full species distribution to develop MPB. As a study case, we produced two MPBs for an administrative region of Argentina using RSD and FSD data sets of 14 species of insects and performed Environmental Niche Factor Analysis to model their ecological niches. Our results evidenced that both MPB were not spatially congruent in their predictions on potential biodiversity, because the ecological niches represented by RSD and FSD data were different in their position and volume. We found that the MPB based on RSD data may underpredict the potential biodiversity of distinct habitats at the landscape level, and that the use of this map may underestimate areas with different conservation potential within an administrative region. These results suggest that the choice of the extent of geographic records used to construct the MPB strongly conditions the quality and credibility of these maps. [ABSTRACT FROM AUTHOR]

On November 5, 2015, the Fundão dam collapsed and released > 60 million m3 of iron-rich mining sediments into the Doce river basin, covering >1000 ha of floodplain soils across ~80 km from the rupture. The characterization of alluvial mud covering and/or mixed with native soil is a priority for successful environmental rehabilitation. Portable X-ray fluorescence (pXRF) spectrometry was used to (1) assess the elemental composition of native soils and alluvial mud across impacted riparian areas; and 2) predict fertility properties of the mud and soils that are crucial for environmental rehabilitation and vegetation establishment (e.g., pH, available macro and micronutrients, cation exchange capacity, organic matter). Native soils and alluvial mud were sampled across impacted areas and analyzed via pXRF and conventional laboratory methods. Random forest (RF) regression was used to predict fertility properties using pXRF data for pooled soil and alluvial mud samples. Mud and native surrounding soils were clearly differentiated based on chemical properties determined via pXRF (mainly SiO2, Al2O3, Fe2O3, TiO2, and MnO). The pXRF data and RF models successfully predicted pH for pooled samples (R2 = 0.80). Moderate predictions were obtained for soil organic matter (R2 = 0.53) and cation exchange capacity (R2 = 0.54). Considering the extent of impacted area and efforts required for successful environmental rehabilitation, the pXRF spectrometer showed great potential for screening impacted areas. It can assess total elemental composition, differentiate alluvial mud from native soils, and reasonably predict related fertility properties in pooled heterogeneous substrates (native soil + mud + river sediments). [ABSTRACT FROM AUTHOR]

In recent years, concern has been increasing regarding the carbon emissions generated by mining activities. China is an extremely large coal producer (3695 Mt/2015) and consumer (3698 Mt/2015), and Shanxi Province (i.e., a major coal-producing province in China) is a crucial element in China's energy conservation and emission reduction goals. In this study, the Pingshuo mining area (PMA) in Shanxi Province was chosen as a case to analyze the dynamic changes in carbon emissions based on the Intergovernmental Panel on Climate Change (IPCC) method, and the factors influencing carbon emissions were analyzed via the IPAT equation. Carbon emission sources in opencast mines mainly included fuel and explosive use, coal mine methane escape, coal and gangue spontaneous combustion, and electricity consumption. The carbon emission of the PMA increased from 4 × 104 Mg in 1986 to 1.05 × 106 Mg in 2015, with an average annual increase of 11.64%. In the PMA, 4.71 × 106 Mg of carbon emissions from fuel consumption accounted for 41.79% of carbon emissions, and 5.26 × 106 Mg of carbon emissions from methane emissions accounted for 46.66%. Carbon emissions from explosives and electricity use were 4.1 × 105 Mg and 8.8 × 105 Mg, respectively. In this mining area, the factors influencing carbon emissions included population, GDP, and coal output. The results of this study not only provide a reference for cleaner production in mining areas but also lay a foundation for the study of global opencast coal mining carbon emissions. [ABSTRACT FROM AUTHOR]

The tree species and its diversity are two critical components to be monitored for sustainable management of forest as well as biodiversity conservation. In the present study, we have classified the tree species and estimated its diversity based on hyperspectral remote sensing data at a fine scale level in the Saranda forest. This area is situated near the mining fields and has a dense forest cover around it. The forest surrounding the study area is exhibiting high-stress condition as evidenced by the dying and dry plant material, consequently affecting tree species and its diversity. The preprocessing of 242 Hyperion (hyperspectral) spectral wavebands resulted in 145 corrected spectral wavebands. The 21 spectral wavebands were selected through discrimination analysis (Walk's Lambda test) for tree species analysis. The SVM (support vector machine), SAM (spectral angle mapper), and MD (minimum distance) algorithms were applied for tree species classification based on ground spectral data obtained from the spectroradiometer. We have identified six local tree species in the study area at the spatial level. The result shows that Sal and Teak tree species are located in the upper and lower hilly sides of two mines (Meghahatuburu and Kiriburu). We have also used hyperspectral narrow banded vegetation indices (VIs) for species diversity estimation based on the field-measured Shannon diversity index. The statistical result shows that NDVI705 (red edge normalized difference vegetation index) is having the best R2 (0.76) and lowest RMSE (0.04) for species diversity estimation. That is why we have used NDVI705 for species diversity estimation. The result shows that higher species diversity values are located in the upper and lower hilly sides of two mines. The linear regression between Hyperion and field measured Shannon index shows the R2 (0.72) and RMSE (0.15). This study will aid in effective geoenvironmental planning and management of forest in the hilltop mining areas. [ABSTRACT FROM AUTHOR]

This study aimed to compare the efficiency of two different sizes of the Surber sampler to assess benthic macroinvertebrates in headwater streams in two Amazonian regions. Two Surber samplers of different sizes were used, one measuring 20 × 20 cm and the other 30 × 30 cm, both with a 0.25-mm net. The number of replicates taken was 6 for the smaller sampler and 3 for the bigger one, maintaining approximately the same total sampled area. The study was carried out in 12 headwater streams with different environmental conditions. Biological metrics were calculated for each size at each site and compared within each stream health category. A two-way analysis of similarities test was performed to compare the community structure assessed by each method at each stream. A normalized sampling effort was used to quantify the number of samples required to correctly sample each site. The data did not show a significant difference between the two sizes regarding the taxonomic recruitment and the community structure sampled at each stream, but differences were found between the two sizes in dominance values and in Shannon index scores for the natural sites. Furthermore, the smaller Surber was able to assess 70% of the estimated richness in all sites, which suggests that it is better to assess benthic macroinvertebrates than the larger Surber. Moreover, the smaller Surber is easier to transport in the field, reducing the effort of the technician, and takes less time to sort the material collected with it, which can reduce the sample processing effort, therefore reducing the cost of the project. [ABSTRACT FROM AUTHOR]

Gold mining operations generate a range of ecological and environmental impacts that can be measured spatially using geographic information system and remote sensing methods. This study assessed land-use and land-cover dynamics in the gold mining area using geographic information system and remote sensing techniques with the aid of Landsat 5 for years 1984, 1994, 2004 and Landsat 8 for 2014 and 2019 obtained from the United States Geological Survey and Remote Pixel Databases using ArcGIS 10.4 and R programming. The result from the study revealed the current changes and how they have evolved over the years where tailings dam and built-up areas increased from 90.5 to 172.9 km2 between the year 1984 and 2019, while mine effluent (return water ponds) and water bodies increased from 14.7 to 18.8 km2 during the same period. The area also experienced increased vegetation from 342.5 to 371.1 km2 (though fluctuating during the study period) an indication that the area has witnessed revegetation in the area. Results from the study further revealed the vegetation health in the area utilises some vegetation indices such as the Global Environmental Monitoring Index, Normalised Difference Impervious Surface Index and Normalised Difference Moisture Index. Findings from the study show that areas with low index values are susceptible to the impact of mining and other anthropogenic activities, whereas high-index areas connote little or no impact. The outcome of this study provides a cost-effective tool for evaluating environmental impacts in mining areas that can drive policy interventions for remediation in affected areas. [ABSTRACT FROM AUTHOR]

This paper presents an investigation on the characteristics of shear stress on normal fault plane by employing the mechanical model and the characteristics of water inrush from floor strata during mining activities by employing numerical model. The shear stress formula on fault plane is obtained by using the solution of a homogeneous half-plane affected by normally distributed forces in the theory of elasticity. The mechanical model shows the variation of shear stress on fault plane with different dip angle and fault reactivation is analyzed according to the shear stress. Based on these, the fracture distribution and seepage distribution on floor strata are numerically simulated by using the RFPA2D-Flow software, and the effect of dip angle on water inrush from floor strata is discussed. These results indicate that the smaller value of dip angle is easier to be reactivated and to produce connecting fractures between floor strata and normal fault comparing with the larger value of dip angle, which provide significant insights into remaining coal pillar with similar geological conditions. [ABSTRACT FROM AUTHOR]

In unregulated mining and processing for Cu and Au, large amounts of heavy metals and metalloids are generated as tails. These wasted by-products could actually pose serious environmental problems. The objective of this study was to assess the potential ability of Alternanthera sessilis and Aster philippinensis thriving abundantly in a small-scale mine processing site at Kias, Benguet, for possible Cu, Pb, Zn, and As uptake. It also aimed to determine the cellular localization of the contaminants within the plant biomass. Alternanthera sessilis and Aster philippinensis exhibited low bioaccumulation factor (BF) and translocation factor (TF) values for Cu, Pb, Zn, and As. The BF and TF values could suggest possible exclusion mechanisms of the plants in avoiding phytotoxicity. SEM-EDX analysis of the Alternanthera sessilis roots indicated higher weight % of Cu, Pb, and As in the epidermis, and Zn in the cortex. On the other hand, Aster philippinensis roots showed high weight % of Zn and As in the epidermis and Cu and Pb in the cortex. The localization of the contaminants in the root epidermal and cortical cells signifies restriction of their mobility to the xylem, preventing migration to the shoot system. The findings of this study suggest that Alternanthera sessilis and Aster philippinensis are considered potential phytostabilizers capable of immobilizing contaminant toxicity in the soil and in the rhizosphere. [ABSTRACT FROM AUTHOR]

This study explores the hydrogeochemical processes and groundwater quality of different aquifers in the Caojiatan coal mine in the Ordos Basin, northwestern China, using classical graphical methods and multivariate analysis. The study found that surface water and groundwater in the Quaternary unconsolidated aquifer (UA) and weathered bedrock zone (WZ) have a HCO3–Ca·Mg hydrochemical type, while the groundwater in the Jurassic Zhiluo aquifer (ZA) and Jurassic Yanan aquifer (YA) are predominantly of the HCO3–Na type. Rock weathering, silicate dissolution, and reverse cation exchange are the dominant hydrogeochemical processes controlling the water chemical variables in the study area. In addition, variations in the hydraulic conductivities and TDS in different aquifers indicate that groundwater residence time is also the main factor controlling the chemical variables. Groundwater in the UA and WZ is suitable for drinking and irrigation, with low ion concentrations. However, the groundwater in ZA and YA must be treated before drinking, because of the high pH value. The excessive concentrations of F-, and high sodium adsorption ratio Na%, and residual sodium carbonate values also make the water unsuitable for irrigation. Mining activities can significantly impact the circulation and occurrence of natural groundwater. Once the groundwater in WZ becomes mine water, it becomes contaminated because of the mixing process with groundwater in ZA and YA. Further, undissolved coal slime and large quantities of oil leaking from fully mechanized mining equipment increase the CODMn levels in the mine water, making the levels higher than in natural groundwater and beyond permissible limits for drinking. [ABSTRACT FROM AUTHOR]

Mining activities can contribute to sustainable development, focusing on economic, environmental, and community aspects. To this purpose, it appears essential to investigate the spatial dimension of mining operations to have a clear picture of the full range of impacts in terms of both opportunities and constrains. The paper illustrates the construction of a geodatabase for supporting planning and management of mining activities in Piedmont Region (Northern Italy). In the geodatabase, all the quarries located in the area are represented at a regional scale, distinguishing by active and inactive sites that have been further divided according to the main categories of extracted materials, namely aggregates, industrial minerals, and ornamental stones. The article discusses how the regional mining mapping can offer an integrated and interdisciplinary representation of the territory under analysis, thus supporting the decision-making processes in the context of the activities related to the Strategic Environmental Assessment of the planning of mining operations. [ABSTRACT FROM AUTHOR]

The anthropogenic salinisation of rivers causes grave environmental problems that are responsible for the degradation of water quality on a worldwide scale as well as for biological changes in aquatic ecosystems. The objectives of the survey were to analyse the structure of the macroinvertebrate communities in the Bolina River, which is currently the second most anthropogenic salinised river in the world, in relation to various types of instream microhabitats and to determine the environmental factors that have a significant effect on the structure of the macroinvertebrate communities. The result of a canonical correspondence analysis (CCA) showed that electrical conductivity, the temperature of the water and the organic matter content in the bottom sediments were the most important factors (statistically significant) that influenced the macroinvertebrate communities in the anthropogenic salinised river. A total of 77 taxa of macroinvertebrates were recorded in the Bolina River. A Kruskal-Wallis one-way ANOVA and multiple comparison post hoc tests revealed statistically significant differences in the median number of taxa and the median density of macroinvertebrates between the various types of microhabitats in the salinised river. The anthropogenic salinisation of a river can lead to a decrease in aquatic biodiversity that favours invasive species over native species. The Bolina River, which has a salinity of up to 33.6‰, is an example of a unique habitat for organisms that are salt tolerant (euryhaline) or eurytopic. It is a route for the spread of alien and invasive invertebrate species including Gammarus tigrinus, Potamopyrgus antipodarum, and Monopylephorus limosus. [ABSTRACT FROM AUTHOR]

The Sassi of Matera, UNESCO site since 1993, represents a human settlement completely integrated in the natural landscape. There, the development of the community is closely connected to the geology since prehistoric times. The Calcarenite di Gravina, a Pleistocene poorly lithified limestone onlapping a large area of the Apulian foreland in southern Italy, is the building stone that people used to carve their houses inside, and build the town outside. The use of calcarenite for housing began in the prehistory with the first human settlement, deepening natural caves which served as dwellings, while the mining activity began in the third century B.C., increasing until the nineteenth century in connection with the urban development of Matera. The calcarenite was carved out on site and used to build houses. In the eighteenth century, the great urban development of the city gave way to large mining activities in the northern area of Matera. Geomorphological analysis through aerial photographs and a geological survey in this area have been carried out to investigate the historical quarrying activities. In the present study, six quarry areas along the Appia Antica road are valuated: the Madonna delle Vergini topographic high; Cava della Palomba; Parco Scultura–Cava Paradiso; Cava del Sole, the Monumental Quarry Remains; Via Ridola inside the Piano, the highest area of Sassi. They represent peculiar and important examples to be safeguarded and valued. Their geomorphological, geostratigraphical and palaeontological elements provide useful information for understanding the territory evolution in the last two millennia. [ABSTRACT FROM AUTHOR]

Long-term mining activities reshape the hydraulic and hydrochemical field, and threaten the safe use of groundwater and ecosystem balance. Here, we concluded the evolution characteristics and processes of karst groundwater system based on the water level and hydrochemistry data of the Carboniferous and Devonian aquifer in Maoping lead-zinc deposit, a representative in southwestern China. After concentrated mining lasting for nearly three decades, this mining area has generated a huge depression cone coupled with decreased level, changed flowpath, massive drainage, and direct hydraulic connection across the aquiclude. However, these two sets of karst aquifers exhibited distinct hydrochemical evolution patterns in particular with respect to sulfate. SO42− and the total dissolved solids (TDS) increased slightly in the Carboniferous aquifer and maintained the hydrochemical type of HCO3 and HCO3·SO4. While, SO42− and TDS in the Devonian aquifer decreased drastically, and the hydrochemical type was converted from SO4 and SO4·HCO3 to HCO3 and HCO3·SO4. Before concentrated mining, pyrite oxidation and dissolution of carbonate minerals mutually promoted each other in sluggish groundwater flow, then generated abnormally high concentrations of SO42−, Ca2+, and Mg2+ in Devonian karst aquifer, causing an illusion of saturation state of gypsum dissolution. At present, SO42− is mainly derived from pyrite oxidation indicated by sulfur isotope except deep groundwater contributed by gypsum dissolution. Groundwater quality in the Devonian aquifer was improved together by the dilution of northern shallow groundwater from the external Carboniferous aquifer and upward recharge of southern deep groundwater itself. Results of principal component analysis (PCA) verified the different recharge resources and mixing process resulted from continuous mining activities, which were the driving forces of hydrochemical evolution. Qualitatively speaking, the disturbing degree of the hydrodynamic field was consistent with the variation degree of hydrochemical filed. This research shed light upon the groundwater system and its evolution induced by intensive mining, which will benefit the future mining project. [ABSTRACT FROM AUTHOR]

Sorption studies were conducted to investigate the effect of the presence of organic acids or exudates released by crops [acetic acid (AA), citric acid (CA) and oxalic acid (OA)] and ethylenediaminetetraacetic acid (EDTA) on the adsorption of carcinogenic cadmium (Cd) by an agricultural podsolic soil acting as a natural adsorbent. Powder X-ray diffraction, X-ray fluorescence, Fourier transform infrared spectroscopy and cation exchange capacity were used to characterize the soil. The effect of pH and changing concentration of the organic acids and Cd on the adsorption was investigated. PHREEQC (short for pH, REdox and EQuilibrium in C language) geochemical modeling was used to determine the speciation of Cd. The podsolic soil was effective as a natural clay adsorbent in capturing Cd, thus preventing mobility to groundwater. In the presence of crops organic acids and EDTA, the adsorption capacity decreased at all initial concentrations of Cd and the extent of reduction followed the sequence: OA < AA < CA < EDTA. The adsorption of Cd onto the soil was best described by Freundlich isotherm in the presence of all acids. The adsorption of Cd decreased as the concentration of crop organic acids increased. Moreover, EDTA totally inhibited the adsorption of Cd at all concentrations. The adsorption of Cd increased in the presence of CA and EDTA at pH greater than 5. The capturing of Cd by the soil will be decreased by the presence of organic acids, thus increasing mobility to groundwater which should be protected from such pollutants. [ABSTRACT FROM AUTHOR]

Mining activities are responsible for the elevated input levels of suspended sediment and hazardous metals into the riverine ecosystem. These have been shown to threaten the riverine fish populations and can even lead to localized population extinction. To date, research on the effects of mining activities on fish has been focused within metal contamination and bioaccumulation and its threat to human consumption, neglecting the effects of suspended sediment. This paper reviews the effects of suspended sediment and metal pollution on riverine ecosystem and fish population by examining the possibilities of genetic changes and population extinction. In addition, possible assessments and studies of the riverine fish population are discussed to cope with the risks from mining activities and fish population declines. [ABSTRACT FROM AUTHOR]

Soil contamination was investigated in the vicinity of Zarshouran gold mine through determination of total concentrations and chemical speciation of As, Cu, Zn, Cd, and Pb. Forty-six surface soil samples at depth of 0-15 cm were collected and analyzed from the mining district. The average concentrations (reported as mg/kg) of As 155.88, Pb 184.22, Cd 8.66, Zn 129.92, Cu 65.06, in the soil samples are much higher than the world average, while Ni and Fe are less than the world average. Examination of the single element distribution plots revealed that enhanced levels of heavy metals are associated with known mineralization zones and depended on the distance from the mine site except for Ni. Geo-accumulation indices and Enrichment Factors performed on the data imply that the collected soils have been significantly influenced by the Au-mining activities. The calculated geoaccumulation values for the soil samples indicated that the surface soils are virtually unpolluted with respect to Fe, and Ni but highly polluted with As and Cd. Enrichment level of Cu and Zn was considerable, while Pb showed very high to extremely high enrichment. The results obtained from the sequential extraction analysis of the metals from all the fine fraction of the soil samples revealed that heavy metals were largely associated with the residual fraction. However, the amounts of metals bound to Fe-Mn oxides and organic matter were relatively higher than those bound to carbonates or those in exchangeable forms. The average speciation percent and risk assessment code (RAC) results revealed that Cd and Pb were mobile in exchangeable phase while As, Pb, Zn and Ni bound to Fe-Mn oxides with a medium risk to the environment. [ABSTRACT FROM AUTHOR]

Antimony (Sb) usually occurs associated with arsenic, lead, and other metal elements in sulfide deposits, and most is currently being extracted from the Karst areas, southwest China. In these areas, the acid generated from the oxidative dissolution of sulfide minerals is neutralized by the abundant carbonates but little is known about the effect of this process on the geochemical behavior of Sb and other contaminants. In this study, physicochemical properties (pH, EC) and the trace elements (Sb, As, Cu, Pb, Zn, Sr, etc.) concentrations in waters from mining-impacted Karstic environments were determined in order to determine their distribution and migration potential. It was found that pH values ranged from 6.51 to 9.82, and EC values varied from 369 to 1705 μs·cm−1 in river water samples. Waters of various types such as adit waters, flotation drainage, leaching waters, and river waters all contained high concentrations of dissolved trace elements, reaching up to 5475 μg·L−1Sb, 1877 μg·L−1As, 10,371 μg·L−1Zn, 1309 μg·L−1 Pb, 46 μg·L−1 Cu, and 1757 μg·L−1 Sr. The elevated concentrations of dissolved Sr indicated that Sr could be considered as an indicator of oxidative dissolution of sulfide minerals in the Karst rivers. A proportion of the trace elements were removed in the streams in the vicinity of the mine due to adsorption onto particulate matter, whereas migration of trace elements in the downstream of mine area was attributed to dispersion in dissolved forms. Strontium and Sb have a strong hydrophilicity compared to the other elements analyzed; in contrast, Pb had a high affinity for suspended particulate matter (SPM). It was also found that downstream sediments had elevated concentrations of mining-derived trace elements, but there was a significant decrease in concentration of contaminants in aqueous phase, suggesting that contaminant behavior was conservative in the water-sediment systems under the oxic conditions prevailing in these waters. There was a good correlation between Sb and As in water-SPM-sediment system, indicating that Sb and As are homologous in water environment of the study area. [ABSTRACT FROM AUTHOR]

The Itataia uranium-phosphate deposit is the largest uranium reserve in Brazil. Rare earth elements (REEs) are commonly associated with phosphate deposits; however, there are no studies on the concentrations of REEs in soils of the Itataia deposit region. Thus, the objective of the research was to evaluate the concentration and spatial variability of REEs in topsoils of Itataia phosphate deposit region. In addition, the influence of soil properties on the geochemistry of REEs was investigated. Results showed that relatively high mean concentrations (mg kg−1) of heavy REEs (Gd 6.01; Tb 1.25; Ho 1.15; Er 4.05; Tm 0.64; Yb 4.61; Lu 0.65) were found in surface soils samples. Soil properties showed weak influence on the geochemical behavior of REEs in soils, except for the clay content. On the other hand, parent material characteristics, such as P and U, had strong influence on REEs concentrations. Spatial distribution patterns of REEs in soils are clearly associated with P and U contents. Therefore, geochemical surveys aiming at the delineation of ore-bearing zones in the region can benefit from our data. The results of this work reinforce the perspective for co-mining of P, U and REEs in this important P-U reserve. [ABSTRACT FROM AUTHOR]

The clam Gafrarium pectinatum was investigated to assess its usefulness as a bioindicator species of metal mining contamination in the New Caledonia lagoon. The uptake and depuration kinetics of Ag, Cd, Co, Cr, and Zn were determined following exposures via seawater, sediment, and food using highly sensitive radiotracer techniques (110mAg, 109Cd, 51Cr, 57Co, and 65Zn). When the clams were exposed to dissolved metals, Co, Zn, and Ag were readily incorporated in their tissues (concentration factors (CF) ranging from 181 to 4982 after 28 days of exposure) and all metals were strongly retained (biological half-lives always >2 months). The estimated transfer factor (TF) in clam tissues after a 35-day sediment exposure was 1 to 4 orders of magnitude lower than the estimated CF, indicating a lower bioavailability of sediment-bound metals than dissolved ones. Once incorporated, metals taken up from sediment and seawater were retained longer than metals ingested with food, indicating that the uptake pathway influences the storage processes of metals in clam tissues. Compilation of our data into a global bioaccumulation model indicated that, except for Ag that essentially originated from food (92%), sediment was the main source of metal bioaccumulation in the clam (more than 80%). These results highlight that bioaccumulation processes strongly depend from one metal to the other. The overall efficient bioaccumulation and retention capacities of the clam G. pectinatum confirm its usefulness as a bioindicator species that can provide time-integrated information about ambient contamination levels in the tropical marine coastal environment. [ABSTRACT FROM AUTHOR]

Abandoned mines are a recurrent problem for nearby communities in Mediterranean regions because mine tailings represent a major source of polymetallic contamination. Metal contaminants are emitted in mining areas and dispersed by wind and water erosion in the surroundings. The goal of this literature review was to identify the specific features of polymetallic contamination arising from abandoned mines in the Mediterranean regions. Mediterranean climate conditions and local geochemical context are the most important factors that control the metal-bearing particle dispersion toward the different compartments of ecosystems. Acid mine drainage, as an important source of damage to the environment, is limited to a certain extent by the predominance of carbonate rocks in the Mediterranean regions. In opposite, aeolian contamination is specific to the semiarid conditions of the Mediterranean climate. In this context, impacts on different compartments such as agricultural soils and edible plants or human populations were underlined. The analysis of environmental laws and regulations of North and South Mediterranean countries shows that one of the main differences is the lack of identification and definition of mining waste as a public concern in the latter countries. In order to limit the transfer of contaminants from mining waste to the different components of the environment, phytostabilization of mine tailings was considered as the more adapted green technology even in the Mediterranean region where water access is limited. Finally, this review of polymetallic pollution from abandoned mines in Mediterranean regions enabled to identify priority actions for future research. [ABSTRACT FROM AUTHOR]

The West Bokaro coalfield is a richest coal-mining belt in the Damodar Valley, India. The extensive mining of the area has resulted in disruption of the groundwater availability in terms of both quantity and quality. This has led to a drinking water crisis, especially during the pre-monsoon period in the West Bokaro coalfield area. The characterization of the hydrogeological system and the artificial recharging of the aquifers might help to better manage the problem of the groundwater-level depletion. For this purpose, seven important hydrogeological factors (water depth, slope, drainage, soil, infiltration, lithology, and landuse) have been considered to define the most suitable locations for artificial groundwater recharging in the mining area. Different thematic maps were prepared from existing maps and data sets, remote-sensing images, and field investigations for identification of the most suitable locations for artificial recharge. Thematic layers for these parameters were prepared, classified, weighted, and integrated into a geographic information system (GIS) environment by means of fuzzy logic. The results of the study indicate that about 29 and 31% of the area are very suitable and suitable for recharging purposes in the West Bokaro coalfield. However, the rest of the area is moderate to unsuitable for recharging due to the ongoing mining and related activities in the study area. The groundwater recharging map of the study area was validated with measured electrical conductivity (EC) values in the groundwater, and it indicated that validation can be accepted for the identification of groundwater recharging sites. These findings are providing useful information for the proper planning and sustainable management of the groundwater resources in the study area. [ABSTRACT FROM AUTHOR]

Key message : The study gives an insight into the effect of the stress produced due to an anthropogenic activity like mining on the secondary xylem, which is one of the most conservative features of plants. Abstract: The anatomy of the wood of mature trees is supposed to be conservative in nature though variations in them can occur due to the possible stressful conditions around the tree. This novel study is concerned with the effect of mining activities on the wood microscopic features of hardwood trees in and around the forest areas of the largest and oldest active open-cast iron ore mines of India. The work was carried out with systematic sampling from trees belonging to 22 different genera and species. The data of the microstructure analyzed using different statistical tools, such as Student's t test, ANOVA, and Fisher's exact test, revealed that there were quite significant variations in the quantitative features of the elements of secondary xylem, though the qualitative features remained more or less the same, with very few significant variations as compared to the control samples of the same species. Estimation of the specific gravity and the iron element content in the stressed and control wood samples was also carried out. The exhaustive results obtained led to the conclusion that Buchanania lanzan was the species which was found to be the sturdiest in the stressed conditions, and on the other hand, the most dominant species of the locality, Shorea robusta, showed the maximum number of variations in its secondary xylem. [ABSTRACT FROM AUTHOR]

The Bayan Obo Mine, the largest rare earth element (REE) deposit ever found in the world, has been mined for nearly 60 years for iron and rare earth elements. To assess the influences of mining activities on geochemical behavior of REEs in soils, 27 surface soil samples and three soil profile samples were collected from different directions in the vicinity of the mine area. The total concentrations of REEs in surface soils varied from 149.75 to 18,891.81 mg kg with an average value of 1906.12 mg kg, which was apparently higher than the average values in China (181 mg kg). The order of the average concentrations of individual REEs in surface soils was similar to that in Bayan Obo ores, which confirmed that the concentration and distribution of REEs in the soils was influenced by the mining activities. The concentrations of single REE in the soil profiles showed a similar trend with depth with an increase at 0-25 cm section, then decreased and remained relatively stable in the deep part. The normalized curves inclined to the right side, showing the conspicuous fractionation between the light and heavy REEs, which supported by the North American Shale Composite (NASC) and Post-Archean Australian Shale (PAAS) normalized concentration ratios calculated for selected elements (La/Yb, La/Sm, Gd/Yb). Slight positive Ce anomaly and negative Eu anomaly were also observed. [ABSTRACT FROM AUTHOR]

In many countries of Latin America (Mexico included), As and other toxic elements in water and soils may have a natural geogenic origin; however, the anthropogenic activities (specially in mining areas) trigger the metal(loid)s mobilization (mainly by acid mine drainage) aggravating the environmental pollution problem. In San Antonio–El Triunfo mining district (SA-ET MD), Baja California Sur State, Mexico, 200 years of intermittent mining activities have left around 800,000 tons of mine waste scattered across 400 km2 of the SA-ET area. Some environmental studies in the area assume mining wastes as the main source of contamination of groundwater (not considering the geothermal source). Moreover, recent studies have shown that the pollution in the region has occurred as consequence of seasonal erosion caused by winds and irregular episodes of heavy rainfall. Nevertheless, the actual potential to release As and other potentially toxic elements as well as the hazardousness derived from this mine waste and the geochemical-mineralogical mechanism that influence such mobilization has not been assessed yet. Through the detailed physicochemical and mineralogical characterization (X-ray diffraction and scanning electron microscopy), this novel study shows that jarosite and arsenolite are the key mineral phases controlling the potential release and arsenic mobilization and therefore the hazardousness of the mining wastes. What is more, from pH and acid base accounting results, it has been found that 35 % of the analyzed samples maintain basic to near-neutral conditions due to the neutralizing potential of aluminosilicates (feldspar, muscovite, etc.), while in the remaining 65 % of analyzed samples, the mineral composition is not enough to neutralize the generated acidity; hence, those samples present the potential of generating acid mine drainage, and consequently, they are considered hazardous. [ABSTRACT FROM AUTHOR]

Brazil is an important country within the global mineral industry. The main reserves of phosphate rock in Brazil are contained in the states of Goiás and Minas Gerais, at the Catalão and Tapira cities, respectively. Atmospheric inputs due to the mining of phosphate rock may have various effects on human health in areas near these types of mines. Thus, this work evaluated the influence of phosphate mining on the chemical composition and annual atmospheric deposition in Catalão (GO) and Tapira (MG), Brazil. The pH of rainwater was 6.90 in Catalão and 6.80 in Tapira. The ionic concentrations (in μeq/L) at both study sites decreased in the following order: Ca > Na > Mg > K for cations and HCO > NO > SO > PO > F > Cl for anions. High Ca content indicates that Ca contributes to the neutralisation of the rainwater pH in both of the areas studied. The annual atmospheric deposition of NO and SO can be attributed to the use of diesel-powered trucks in and around mining areas. Soil dust derived is responsible for the annual atmospheric deposition of Na and K. Phosphate mining activities are the main source of the annual atmospheric deposition of PO and F. [ABSTRACT FROM AUTHOR]

To reconstruct the history of environmental degradation in Sanliqi Lake (Daye City, central China), multiple proxies were analyzed in a sedimentary core which was dated using Cs and spheroidal carbonaceous particles (SCPs). The results show that Sanliqi Lake has experienced serious degradation during the past 60 years, resulting from a large influx of metals and nutrients. Expansion of agricultural and industrial activities between 1945 and 1993 enhanced nutrient and metal enrichment, indicated by increases in metals, SCPs, magnetic susceptibility, total phosphorus, total nitrogen and total organic carbon. Further enrichment of Zn, Cd, Ni and Cr after 1993 was linked to a recent intensification of mining activities. Decreases in Cu and Pb after 2006 probably resulted from recent environmental remediation. This study verified the coupling between lake sediment pollution and human activities in Daye City during the past 60 years. The reconstructed history of lake pollution can provide reference information for continued restoration of Sanliqi Lake and other similar heavily polluted lakes in the developing regions. [ABSTRACT FROM AUTHOR]

Mining activities and resulting wastes can be considered one of the most important sources of toxic metals and metalloids in the environment. To assess environmental risk in the surrounding areas of old abandoned W-Sn and Pb-Zn mines and resulting tailings and rejected materials, 333 samples were collected in stream sediments under the influence of abandoned mines. Samples were prepared and analyzed for Fe, Ba, P, Cu, Cr, Ag, B, Zn, Be, Y, Nb, Pb, Ni, V, Mn, Mo, As, W, Co, Cd, Sn and U. The inexistence of Portuguese legislation concerning parametric values for stream sediments led to the application of a quantitative index for progressive contamination on stream sediments, the Geoaccumulation Index (Igeo), as variables to create risk maps. A first exploratory multivariate statistical analysis, using the Principal Component Analysis (PCA), applied to the obtained Igeos, shows a first factor (F1) explaining the dependence of P and B (positive correlation with the axis) and the inverse correlation of these two elements with the cluster formed by Cr, Ni and V (negative correlation with the axis); the second factor (F2) explains Ni, Fe, Zn and As; Cd and U Igeos are not explained in the new factorial space and, therefore, are characterized individually. The variographic studies showed the existence of spatial structure for the new synthesis variables (F1, F2) as well as for Cd and U Igeos. The experimental point-support data was then interpolated using ordinary kriging within a narrow search window as shown in the fitted variogram models. The obtained maps show extremely high levels of pollution in Cd and W and strongly high levels of pollution in Cr, B, Ag, Zn and Pb. The accumulation of these elements in the studied stream sediments is higher on the abandoned mining areas and in their vicinity. [ABSTRACT FROM AUTHOR]

Consideration of human influences is crucial to understanding the coastal sediment supply and associated shoreline responses prior to undertaking coastal hazard management studies. Observation of the widening of some selected Indian beaches, especially over the last 6 decades, is of significance. From this perspective, Miramar Beach, Goa, India, was studied using three ground-penetrating radar shallow subsurface profiles (4 m depth). Based on a series of depositional siliciclastic packages, six progradational packages were recognised, which were interrupted by sharp erosional boundaries. These erosional boundaries represent transgressive phases of the shoreline migration. It was observed that the shoreline migration is coupled with the deposition and erosion of sediments, and this is supported by the historical admiralty charts. The optically simulated luminescence dating of the sediments collected at the first progradation period reveals that the age corresponds to the years 1952-1957, which also corroborates the information provided by the local populace. In the past 6 decades, the shoreline growth has been rapid because of the heavy sediment influx from the Mandovi River caused by increased mining activities (since the 1950s) in upstream areas. Since the 1950s, the shoreline has prograded rapidly, building a beach from ~40 to ~280 m wide (average rate of 4 m/year) in response to enhanced sediment supply from the Mandovi River created by mining activities upstream. Superimposed on this overall regressive trend is a series of deposition and erosion cycles. Perhaps, if a similar trend continues, then there will possibly be a further widening of the beach in the future. A close monitoring network is needed to understand the causes of the cycles in shoreline position and to predict their future behaviour. The present investigation on the nature of the coastal response to anthropogenic activities in a river basin as well as the role of short-time cycles on shoreline behaviour in the last 6 decades could be an ideal reference study and motivate the search for similar areas along other coastal locations. [ABSTRACT FROM AUTHOR]

In the Panasqueira mine area of central Portugal, some environmental media show higher metal(loid) concentrations when compared with the local geochemical background and the values proposed in the literature for these environmental media. In order to evaluate the effect of the external contamination on selected indexes of internal dose, As, Cd, Cu, Cr, Fe, Hg, Mg, Mn, Mo, Ni, Pb, S, Se, Si, and Zn were quantified by inductively coupled plasma mass spectrometry and inductively coupled plasma optical emission spectrometry in blood, urine, hair and nail samples from individuals environmentally ( N = 41) and occupationally exposed ( N = 41). A matched control group ( N = 40) was also studied, and data from the three groups were compared. Results obtained agreed with those reported by environmental studies performed in this area, pointing to populations living nearby and working in the mine being exposed to metal(loid)s originated from mining activities. Arsenic was the element with the highest increase in exposed populations. The concentration of other elements such as Cr, Mg, Mn, Mo, Ni, Pb, S, Se, and Zn was also increased, although at a lesser extent, specifically in the individuals environmentally exposed and in females. These findings confirm the need for competent authorities to act as soon as possible in this area and implement strategies aimed to protect exposed populations and the entire ecosystem. [ABSTRACT FROM AUTHOR]

Purpose: The impacts of mining contaminations and physico-chemical properties and geochemistry of mine tailings on the density, richness, biodiversity, evolution and succession of plant species and vegetation recovery in the mining area is very poorly reported in the literature. Therefore, the present study conducted an investigation on vegetation development and succession of plant communities at the abandoned São Domingos pyrite mining area. Materials and methods: We conducted the field survey to estimate the vegetation development and succession of plant communities, collect vegetation (plant species, lichen and moss) and tailing (and soil) samples, and finally analyzed the physico-chemical and geochemical properties and metal levels in mine tailings, soil and vegetation samples. Results and discussion: The results showed that the communities of low height and biomass like grass, legume, shrub, moss and lichen were dominating on the mine tailings and waste dumps at the inner sites and center of the mine, and the vegetation coverage was explicitly very poor. The reddish brown colluvia had poor soil quality, but high acidity and metal concentrations. However, at the outer edge of the mine the loamy soil and relatively lower acidity and metal contamination favored the higher vegetation cover and a gradual increase in the number of species and plant succession, where the taller, higher biomass and broad leaf trees were abundantly grown forming a dense forest and canopy. The succession of several plant communities dominating in the mining area, vegetation coverage and species richness were strongly related to the different levels of contamination, soil properties and adverse factors of mine tailings. Conclusions: Although the high concentrations of toxic trace elements and low pH soil are important factors for limiting the plant growth, however, proper soil development with enriched nutrients and properties on mining wastes, by either natural or external soil aided process, can help to promote the high vegetation growth, mine rehabilitation and ecological restoration of the mining degraded lands. [ABSTRACT FROM AUTHOR]

The distribution of trace elements throughout mining areas is an important issue because abandoned tailings could be a major source of environmental pollution. In order to analyze the spatial variation of trace elements in a zone where mining activities took place and to identify pollution sources in the study area, a three-step study was carried out at a regional, at a local, and a detailed scale. In addition, a conceptual model of trace elements dispersion was established and confirmed by a geographic information system. The results obtained allowed to establish points affected by primary, secondary, and tertiary contamination, according to their proximity to contamination sources and as a function of attenuation processes which could take place in the studied area. [ABSTRACT FROM AUTHOR]

Heavy metal levels in hair of residents living in villages around Fenghuang mine were investigated. Samples belonging to mine areas showed the highest values, with mean concentrations (mg kg) of 0.17 for Cd, 8.67 for Pb, 0.11 for As, 2.19 for Hg, and 0.64 for Se. Significant correlations ( p < 0.01) were found between Cd-Pb, Cd-As, Pb-As, and Se-Hg. There is no significant difference in any of the elements among age groups. However, significant differences in Cd and Pb levels were found between genders. Results revealed that children and females were more susceptible to Cd and Pb exposure. [ABSTRACT FROM AUTHOR]

Levels of seven metals (Mn, Cu, Zn, Pb, Cr, Cd, and Se) in the scalp hair of Daicun and Xiangtian inhabitants were determined by ICP-MS/AFS. Daicun, as an experimental site, is near Dexing Copper Mine, Jiangxi Province, China, and exposed to mining pollution; Xiangtian, as a control site, is free from any mining and other industrial pollution. The heavy metal distribution in the scalp hair of the two diverse population segments exposed to different environments was discussed against the background of the heavy metal content of local plants, waters, and soils. The results show: 1) Levels of Cu, Zn, Pb, Cr, and Cd in the scalp hair of Daicun inhabitants were higher compared with Xiangtian counterparts which showed higher comparative levels of Se and Mn. But there were no significant differences of the levels of Cu and Zn in the hair samples between the two villages. In the hair of the inhabitants in the two villages, the levels for Se, Zn, and Cu were lower, while the level for Mn was higher, than the corresponding levels from other regions of the world. Compared with the standard issued by the Trace Element Research Council of China for Chinese inhabitants there were serious Se, Zn, Cu and Cr-deficiency phenomena in the hair samples from Daicun and Xiangtian. 2) Against the geological background of high levels of Zn, Cu, Se and Cr, there were deficiencies of Zn, Cu, Se and Cr in the hair samples of the Daicun population. This may have been caused by the distribution forms of the heavy metals in the soils, and antagonism among the elements. 3) Principal Component Analysis (PCA) and Cluster Analysis (CA) indicated that the origins of the heavy metals in the hair samples from the two villages had some differences as well as some similarities, this should be contributed mainly to the influence of the mining activities. [ABSTRACT FROM AUTHOR]

In this paper, the cadmium distribution in Certej River sediments in an area seriously affected by intense mining activities has been studied. The main objective of this study was the evaluation of partition of this metal into different operational defined fractions by sequential extractions. Community Bureau of Reference (BCR) sequential extraction was used to isolate different fractions. The sediment quality was assessed both upstream and downstream the pollution input points, along the Certej River, in order to reveal a possible accumulation of cadmium in sediments and the seasonal changes in cadmium concentrations in BCR sediment phases. Our results reveal that most of the cadmium content is divided between both the soluble and iron and manganese hydrated oxide fractions. Based on total cadmium concentrations in sediments, the enrichment factors were estimated using aluminum as normalizing element and the regression curve Cd/Al corresponding to the geochemical background of the studied area. [ABSTRACT FROM AUTHOR]

Environmental impact assessment is now an integral part of mining operations. Remote sensing data enables the identification, delineating, and monitoring of pollution sources and affected areas, including derelict land, and changes in surface land use and to water bodies. The aim of this work was to evaluate the use of multi-temporal Landsat-5 and Landsat-7 images, SPOT Panchromatic, and ASTER data to map the natural environment on a local scale, and to assess the impact of mining activities by indicating the changes on land and water resources. Three case studies are presented: Lake Vegoritis and the Amynteon mine (both located in northern Greece) and the Lavrio mine area, in central Greece. We found that using high resolution satellite remote sensing data and state of the art GIS techniques with parallel development of a fully integrated geospatial database system provided monitoring and feedback at appropriate spatial scales; therefore, such data can be used for long-term environmental management and monitoring of reclamation and rehabilitation of mining areas. [ABSTRACT FROM AUTHOR]

This research focuses on the heavy metal contamination of the paddy soils and rice from Kočani Field (eastern Macedonia) resulting from irrigation by riverine water impacted by past and present base-metal mining activities and acid mine drainage. Very high concentrations of As, Cd, Cu, Pb and Zn were found in the paddy soils (47.6, 6.4, 99, 983 and 1,245 μg g−1) and the rice (0.53, 0.31, 5.8, 0.5 and 67 μg g−1) in the western part of Kočani Field, close to the Zletovska River, which drains the mining facilities of the Pb–Zn mine in Zletovo. In terms of health risk, the observed highest concentrations of these elements in the rice could have an effect on human health and should be the subject of further investigations. [ABSTRACT FROM AUTHOR]

In southern Chile, with a mild and rainy climate, high levels of heavy metals have been detected in many gold placer deposits. Many of the contaminants pose risks to human life, and consequently damage the trofic chain in this environment. The study zones selected correspond to the handicraft gold-bearing sands of Rio Gato (Los Muermos), Carelmapu and Cucao. These are all located in the X Region of “Los Lagos” in Chile. The type of methodology used in the characterization of the associated mineralization consists of testing each representative sample with a grain size distribution, statistical parameter analysis and a mineralogical analysis, using a binocular magnifying glass, a petrographic microscope, XRD and SEM/EDX. The chemical composition was defined by means of X ray fluorescence and micro-chemical analysis. The results of the study about sediments in southern Chile are presented. The major concentrations of heavy minerals are generally located in areas of dynamic river energy. In the samples, more than 70% of the heavy minerals were distributed among grain sizes corresponding to thin sand with good grain selection (meshes of 0.25–0.06 mm). The main mineral phases present in the analysed samples were gold, zircon, olivine, ilmenite, hornblende, hypersthene, hematite, garnet, chromite, chlorite, augite, amphibolitic-epidote, etc. The main heavy metals found as a result of the study were mercury, lead, cadmium, chrome, tellurium, indium, zinc, cobalt, copper, platinum, gold, etc., and as well some less common elements like cerium, praseodymium, gadolinium, neodymium, samarium and lanthanum. This research work is only a starting point for carrying out a risk probability mapping of heavy metals and the mineralogy of the Cucao, Carelmapu and Rio Gato gold-bearing sands. [ABSTRACT FROM AUTHOR]

The Zlata Idka village is a typical mountainous settlement. As a consequence of more than 500 years of mining activity, its environment has been extensively affected by pollution from potentially toxic elements. This paper presents the results of an environmental-geochemical and health research in the Zlata Idka village, Slovakia. Geochemical analysis indicates that arsenic (As) and antimony (Sb) are enriched in soils, groundwater, surface water and stream sediments. The average As and Sb contents are 892 mg/kg and 818 mg/kg in soils, 195 mg/kg and 249 mg/kg in stream sediments, 0.028 mg/l and 0.021 mg/l in groundwater and 0.024 mg/l and 0.034 mg/l in surface water. Arsenic and Sb concentrations exceed upper permissible limits in locally grown vegetables. Within the epidemiological research the As and Sb contents in human tissues and fluids have been observed (blood, urine, nails and hair) in approximately one third of the village’s population (120 respondents). The average As and Sb concentrations were 16.3 μg/l and 3.8 μg/l in blood, 15.8 μg/l and 18.8 μg/l in urine, 3,179 μg/kg and 1,140 μg/kg in nails and 379 μg/kg and 357 μg/kg in hair. These concentrations are comparatively much higher than the average population. Health risk calculations for the ingestion of soil, water, and vegetables indicates a very high carcinogenic risk (>1/1,000) for as content in soil and water. The hazard quotient [HQ=average daily dose (ADD)/reference dose (RfD)] calculation method indicates a HQ>1 for groundwater As and Sb concentrations. [ABSTRACT FROM AUTHOR]

Trace element contamination caused by mining is a serious environmental problem. The potential effects of exploiting the Yunfu pyrite mine (southern China) on soil were investigated by determining trace elements in 56 surface soil samples from the vicinity of the Yunfu pyrite mine. The samples were acid dissolved and measured by an inductively coupled plasma mass spectrometry (ICP-MS). Principal component analysis and hierarchical cluster analysis were used to identify factors influencing the trace element contents and possible sources of the trace elements. The degree of trace element pollution was determined using the geological accumulation index Igeo. Monte Carlo simulations were used to assess the health risks posed. The results show that (1) six factors (parent material, mining activities, ore composition, rainfall, terrain, and other inputs) strongly affected the trace element contents of the soil samples. (2) There were three groups of trace elements, according to their possible sources. One group (Cs, Ga, Ge, Hf, Nb, Rb, Ta, Th, Ti, U, and Zr) mainly originated in parent rocks. Another group (Cr, Ni, Sr, and V) was mainly supplied by industrial plants and traffic emissions. The third group (Ba, Co, Cu, Mn, Pb, and Zn) was mainly supplied through pyrite ore exploitation processes. (3) Some samples were slightly to moderately polluted with Cs, Ga, Ge, Nb, Rb, Ta, and Ti. Most samples were moderately to highly polluted with Ba, Co, Cu, Mn, Pb, and Zn. (4) Trace elements in soil pose strong non-carcinogenic and carcinogenic health risks to people (particularly children) living near the Yunfu pyrite mine. [ABSTRACT FROM AUTHOR]

Large amounts of heavy metal are released by mining and industrial activities to the surrounding environment, raising great concerns regarding the effects of environmental exposure to pollutants on human health. A combination of total and bioaccessible contents, spatial analysis, cluster analysis, and positive matrix factorization model was successfully used to determine the status and sources of heavy metals in a small farmland under long-term influences of mining and industries activities in this study. The results show that the average contents of arsenic (As), cadmium (Cd), lead (Pb), and zinc (Zn) in agricultural soils exceed the Chinese national standard 2.18, 5.95, 3.46, and 1.33 times, respectively. Cd poses the highest potential on human health with a mean geo-accumulation index (Igeo) of 4.51 and a bioaccessible ratio of 37.41%, followed by Pb, which has a mean Igeo of 1.58 and a bioaccessible ratio of 63.24%. The significant correlation (P < 0.01) was found between the total and bioaccessible four contaminated metal contents (As, Cd, Pb, and Zn), indicating that total concentration of heavy metals could be effective indicators on bioaccessibility in this study. The As was attributed to the atmospheric deposition, Cd and Zn were mainly derived from mining activities, and Pb contamination is highly related with cement plant. Compared to atmospheric deposition, industrial activities, and soil parent materials, mining activities has the greatest influence on the enrichments of the total heavy metals in agricultural soils with the proportion of 47.9%. [ABSTRACT FROM AUTHOR]