• Economic and Environmental Geology
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• v.38 no.5 s.174
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• pp.513-523
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• 2005

The contamination of soils and groundwaters in the Dalcheon mine area, Ulsan, is investigated, and a natural attenuation capacity on redox and pH is evaluated. Arsenopyrite, the major source of arsenic pollution in the Dalcheon mine area, is contained up to $2\%$ in tailings. Furthermore, As-bearing minerals such as loellingite, nicolite, rammelsbergite, gersdorffite cobaltite and pyrite are also source of arsenic contamination, which show various concentration of arsenic each other. Surface of pyrite and arsenopyrite in tailings partly oxidized into Fe-arsenates and Fe-oxides, which means a progressive weathering process. There is no relationship between pH and arsenic content in groundwaters, otherwise Eh and arsenic concentration in unsaturated and saturated groundwater shows positive relationship. RMB (Red Mud Bauxite) could be useful as a trigger on natural attenuation due to superior ability of removal capacity of arsenic when contaminated soil and groundwater in the Dalcheon mine area are remediated.

• Journal of Soil and Groundwater Environment
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• v.18 no.5
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• pp.56-64
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• 2013

After the law has been enacted for the prevention and recovery of mining damage in 2005, efforts of remediation have been started to recover heavy metal contaminated soils in agricultural land near mining sites. As part of an effort, the upper part of cultivation layer has been treated through covering up with clean soil, but the heavy metal contamination could be still spreaded to the surrounding areas because heavy metals may be remained in the lower part of cultivation layers. In this study, the most frequently occurring arsenic (As) contamination was selected to study in agricultural land nearby an abandoned metal mining site. We applied separation technologies considering the differences in the physical characteristics of soil particles (particle size, density, magnetic properties, hydrophobicity, etc.). Based on physical and chemical properties of arsenic (As) containing particles in agricultural lands nearby mining sites, we applied sieve separation, specific gravity separation, magnetic separation, and flotation separation to remove arsenic (As)-containing particles in the contaminated soil. Results of this study show that the removal efficiency of arsenic (As) were higher in the order of the magnetic separation, flotation separation, specific gravity separation and sieve separation.

• Journal of Wetlands Research
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• v.24 no.2
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• pp.142-154
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• 2022

Arsenic (As) contamination in groundwater is one of the main problems in Bangladesh. As toxicity causes serious human health problems such as edema, skin cancer, bladder cancer, lung cancer, hyperkeratosis, premature birth, and black foot disease. As contamination in groundwater mainly originates from the geological characteristics of the area due to the influence of anthropogenic activities. Since most of the people in Bangladesh rely on tube well for drinking water, it is necessary to investigate the current status of As pollution and identify the treatment technologies that can be used to provide arsenic-free drinking water in water-scarce areas. A total of 92 papers were reviewed in this study to present a complete overview of the recent status of groundwater As contamination in Bangladesh and different low-cost remediation technologies. A method for evaluating the relative feasibility of different treatment technologies was also utilized to determine the most appropriate technologies for groundwater As treatment in Bangladesh. The districts with the highest groundwater As contamination include Brahamanbariya, Tangail, Barisal, Pabna, Patuakhali, Kurigram, Magura, and Faridpur, with concentrations exceeding 0.05 mg/L. Only six districts had relatively low groundwater arsenic concentrations (0.01 mg/L), including Kushtia, Khagrachari, Jessore, Dinajpur, Meherpur, and Munshiganj. There were a number of technologies used for treating As in water, but aerated electrocoagulation, Mg-Fe-based hydrotalcite-like compound, and electro-chemical As remediation (ECAR) reactor were found to be the most feasible treatment methods for As. Overall, the investment, operational, and maintenance costs, availability of materials, and expertise requirements should be considered when selecting the most appropriate treatment method for As in water.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.347-350
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• 2002

Arsenic speciation changes between As(V) and As(III) are subject to changes in accordance with redox conditions in the environment. It is common to find contaminated sites associated with mixed wastes including both organic pollutants and heavy metals. We conducted microcosm experiment under hypothesis that the co-disposed organic pollutants would influence on the arsenic forms and concentrations, via degradation of the organic pollutants and the consequent impact on the redox conditions in soil. Artificially contaminated soil samples were run for 40 days with control samples without artificial contamination. We noticed arsenic in the contaminated soil showed different behaviour compared with the arsenic in the control soil. The findings indicate degradation of organic pollutants in the contaminated soil influenced on the arsenic speciation and concentrations. A further work is needed to understand the process quantitatively. However, we could confirm that degradation of organic pollutants can influence on the abiotic processes associated with geochemical reactions in contaminated soil. Degradation of organic pollutants can increase the mobility and toxicity of arsenic in soil and sediment by changing redox conditions in the geological media and subsequently from As(V) to As(III).

• Advances in concrete construction
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• v.16 no.1
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• pp.69-78
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• 2023

This investigation delves into the adverse repercussions stemming from the impact of arsenic on steel pipes concealed within soil designated for rice cultivation. Simultaneously, the study aims to ascertain effective techniques for detecting arsenic in the soil and to provide strategies for mitigating the corrosion of steel pipes. The realm of nanotechnology presents promising avenues for addressing the intricate intersection of renewable energy, oil, and environmental pollution from a novel perspective. Nanostructured materials, characterized by distinct chemical and physical attributes, unveil novel pathways for pioneering materials that exert a substantial impact across diverse realms of food production, storage, packaging, and quality control. Within the scope of the food industry, the scope of nanotechnology encompasses processes, storage methodologies, packaging paradigms, and safeguards to ensure the safety of consumables. Of particular note, silver nanoparticles, in addition to their commendable antibacterial efficacy, boast anti-fungal and anti-inflammatory prowess, environmental compatibility, minimal irritability and allergenicity, resilience to microbial antagonism, thermal stability, and robustness. Confronting the pressing issue of arsenic contamination within both environmental settings and the food supply is of paramount importance to preserve public health and ecological equilibrium. In response, this study introduces detection kits predicated upon silver nanoparticles, providing an expeditious and economically feasible avenue for identifying arsenic concentrations ranging from 0.5 to 3 ppm within rice. Subsequent quantification employs Hydride Atomic Absorption Spectroscopy (HG-AAS), which features a detection threshold of 0.05 ㎍/l. A salient advantage inherent in the HG-AAS methodology lies in its capacity to segregate analytes from the sample matrix, thereby significantly reducing instances of spectral interference. Importantly, the presence of arsenic in the soil beneath rice cultivation establishes a causative link to steel pipe corrosion, with potential consequences extending to food contamination-an intricate facet embedded within the broader tapestry of renewable energy, oil, and environmental pollution.

• Journal of Soil and Groundwater Environment
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• v.23 no.5
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• pp.17-25
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• 2018

The Boroo area in Mongolia is known to have been contaminated with heavy metals due to irregular gold mining activities and the release of mercury from gold extraction process. Soil and mine tailings were collected to analyze contamination patterns of heavy metals in the Boroo area. Analyses revealed that mercury, arsenic and cadmium concentrations exceeded the regulatory standard of the nation (Mongolia National Standard). In case of mercury, about 80% of the survey area was over the limit and the concentration distribution heavily influenced by influx of mercury through water transport. Soil contamination by arsenic was most severe that the concentration exceeded the regulatory limit in almost entire survey area, showing peak concentrations at nearby streams and river along with ore processing facilities. For cadmium, about 20% of the survey area was over the limit with the concentration distribution similar to that of arsenic.

• Environmental Engineering Research
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• v.13 no.1
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• pp.33-40
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• 2008

Levels of arsenic in stream and reservoir waters affected by an abandoned gold mine were examined. The abandoned mine has been left without proper civil and remedial works preventing potential environmental hazards. Field and laboratory chemical analyses revealed that the stream waters downgradient from the mine area were severely contaminated with arsenic and furthermore the reservoir water, 2-3 km away from the mine, also contained substantial levels of As, far exceeding the Korean stream water standard. Relatively higher pH values (6.5-9.4) enhanced mobility of As and mainly sustained substantial As concentration in waters. Chemistries of the stream water, groundwater and reservoir water were dominated by two main factors including effects of mine effluent and anthropogenic agricultural activities. Considering that there has been a substantial As input to the reservoir and the reservoir water has been used for agricultural and domestic uses, immediate remedial works are essentially required.

• International Journal of Advanced Culture Technology
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• v.8 no.2
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• pp.283-288
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• 2020

This study investigated the purification process of groundwater contaminated with zinc and arsenic using a permeable reactive barrier with a zero-valent iron/pumice mixture. We determined the removal rates of the contaminants for 30 days. In this study, column reactor filled with the zero-valent iron/pumice reactive mixture was used. Experimental results showed that the mixture exhibited an almost complete removal of the zinc and arsenic ions. Arsenic was removed via co-precipitation and adsorption processes while zinc ions were asorbed in active sites.The purification process of water from the metal ionscontinued for 30 days with constant hydraulic conductivity because of the enhanced porosity of the pumice and interparticle distance between the zero-valent iron and pumice. Contaminants removal rates and the remediation mechanism for each reactive system are described in this paper.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.10a
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• pp.171-171
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• 2005

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.10a
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• pp.91-92
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• 2005