• Economic and Environmental Geology
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• v.44 no.3
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• pp.203-215
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• 2011

Geochemical and mineralogical properties of a contamited soil should be taken into account to decide a remediation strategy for a given contaminant because development and optimization of soil remedial technologies are based on geochemical and mineralogical separation techniques. The objective of this study was to investigate the geochemical and mineralogical characteristics of arsenic-contaminated soils. The arsenic-contaminated soil samples were obtained from Chonam gold mine, Gwangyang, Chonnam, Particle size analysis, sequential extraction, and mineralogical analyses were used to characterize geochemical and mineralogical characteristics of the As-contaminated soils. Particle size analyses of the As-contaminated soils showed the soils contained 17-36% sand, 25-54% silt, 9-28% clay and the soil texture were sandy loam, loam, and silt loam. The soil pH ranged from 4.5 to 6.6. The amount of arsenic concentrations from the sequential soil leaching is mainly associated with iron oxides (1 to 75%) and residuals (12 to 91%). Major minerals of sand and silt fractions in the soils were feldspar, kaolinite, mica, and quartz and minor mineral of which is an iron oxide. Major minerals of clay fraction were composed of illite, kaolinite, quartz, and vermiculite. And minor minerals are iron oxide and rutile. The geochemical and mineralogical analyses indicated the arsenic is adsorbed or coprecipitated with iron oxides or phyllosilicate minerals. The results may provide understanding of geochemical and mineralogical characteristics for the site remediation of arsenic-contaminated soils.

• Spatial Information Research
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• v.20 no.4
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• pp.17-27
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• 2012

This study was performed to evaluate the spatial distribution of heavy metals using principal component analysis and Ordinary Kriging technique in the Gangwon Mine site. In the soils from the sub soil, the contents of Zn and Ni in the PC1 were gradually dispersed from south to north direction, while the components of Cd and Hg in the PC2 showed an increase significantly from middle-south area in the Gangwon Mine site. According to the cluster analysis, pollutant metals of As and Cu were presented a strong spatial autocorrelation structure in cluster D. The concentration of As was 0.83mg/kg and shown to increase from the south to north direction. The spatial distribution maps of the soil components using geostatistical method might be important in future soil remediation studies and help decision-makers assess the potential health risk affects of the abandoned mining sites.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.549-555
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• 2013

Human influence on soil formation has dramatically increased as the development of human civilization and industry. Increase of anthropogenic soils induced research of those soils; classification, chemical and physical characteristics and plant growth of anthropogenic soils. However there have been no reports on soil pore properties from the anthropogenic soils so far. Therefore the objectives of this study were to test computer tomography (CT) to characterize physical properties of an anthropogenic paddy field soil and to find differences between natural and anthropogenic paddy field soils. Soil samples of a natural paddy field were taken from Ansung, Gyeonggi-do (Ansung site), and samples of an anthropogenic paddy field were from Gumi in Gyeongsangnam-do (Gasan) where paddy fields were remodeled in 2011-2012. Samples were taken at three different depths and analyzed for routine physical properties and CT scans. CT scan provided 3 dimensional images to calculate pore size, length and tortuosity of soil pores. Fractal analysis was applied to quantify pore structure within soil images. The results of measured physical properties (bulk density, porosity) did not show differences across depths and sites, but hardness and water content had differences. These differences repeated within the results of pore morphology. Top soil samples from both sites had greater pore numbers and sizes than others. Fractal analyses showed that top soils had more heterogeneous pore structures than others. The bottom layer of the Gasan site showed more degradation of pore properties than ploughpan and bottom layers from the Ansung site. These results concluded that anthropogenic soils may have more degraded pore properties as depth increases. The remodeled paddy fields may need more fundamental remediation to improve physical conditions. This study suggests that pore analyses using CT can provide important information of physical conditions from anthropogenic soils.

• Journal of Environmental Impact Assessment
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• v.25 no.5
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• pp.333-344
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• 2016

In this study, the efficiency of natural attenuation was evaluated through the hydrogeological characteristics such as monitoring and analyses, tracer tests, chemical composition analysis of the groundwater at a military site contaminated by petroleum hydrocarbon in korea. Also, based on the results, the natural attenuation rate by distance and the expressed biodegradation capacity(EBC) was evaluated. The regression slope of -0.0248($K/V_x$) and bulk attenuation rate of $1.7{\times}10^{-3}/day$ were calculated respectively. The range of total expressed biodegradation capacity(EBC) of BTEX was shown from 9.1 mg/L to 10.0 mg/L(average 9.7 mg/L). It was confirmed that the denitrification which was expressed about 63.6% in the total EBC is the largest influence redox process. Consequently, the biodegradation capacity is considered to be sufficient for remediation in the BTEX average concentration of 1.326 mg/L.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.14 no.2
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• pp.189-200
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• 2016

The Republic of Tajikistan has ten former uranium mining sites. The total volume of all tailings is approximately 55 million tonnes, and the covered area is more than 200 hectares. The safe management of legacy uranium mining and tailing sites has become an issue of concern. Depending on the performance requirements and site-specific conditions (location in an arid, semiarid or humid region), a cover system for uranium tailings sites could be constructed using several material layers using both natural and man-made materials. The purpose of this study is to find a feasible cost-effective cover system design for the Degmay uranium tailings site which could provide a long period (100 years) of protection. The HELP computer code was used in the evaluation of potential Degmay cover system designs. As a result of this study, a cover system with 70 cm thick percolation layer, 30 cm thick drainage layer, geomembrane liner and 60 cm thick barrier soil layer is recommended because it minimizes cover thickness and would be the most cost-effective design.

• Journal of Soil and Groundwater Environment
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• v.17 no.3
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• pp.21-31
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• 2012

This paper presents the short-term and long-term measures to determine the fugitive dust concentration in a contaminated site, which is a crucial step for the determination of particulate emission factor (PEF) for risk assessment. As a long-term measure, USEPA method employing Q/C value (inverse of the ratio of the geometric mean air concentration to the emission flux at center of a 0.5-acre square source) seems to be suitable as it reflects regional-specific meteorological conditions. However, it requires nation-wide database collection and interpretation. Use of ASTM method is an alternative as a short-term measure. The method is readily field-applicable as PEF calculation equation is simple and input parameters can be easily derived at the site of interest as well without the nation-wide efforts. Using ASTM method, PEF at the Former Janghang Smelter Site was determined. According to various mode of aggregate size distribution and fractions of vegetative cover, which are the most important factors in PEF calculation, PEF values at the Former Janghang Smelter Site varied greatly. When the mode of aggregate size distribution was set at 0.25 mm, PEF values at the Former Janghang Smelter Site was 5~20 times higher than the default PEF value (i.e., 35 ${\mu}g/m^3$) shown in the current Korean Soil Contamination Risk Assessment Guidance. On contrast, when the mode was set at 2 mm, PEF values at the Former Janghang Smelter Site was 160~640 times lower than the default PEF value in the Korean Guidance.

• Journal of Soil and Groundwater Environment
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• v.12 no.1
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• pp.87-96
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• 2007

Risk assessment was carried out in order to improve the remediation and management strategy on a contaminated gunnery site, where a flood control reservoir is under construction nearby. Six chemicals, including explosive chemicals and heavy metals, which were suspected to possess risk to humans by leaching events from the site were the target pollutants for the assessment. A site-specific conceptual site model was constructed based on effective, reasonable exposure pathways to avoid any overestimation of the risk. Also, conservative default values were adapted to prevent underestimation of the risk when site-specific values were not available. The risks of the six contaminants were calculated by API's Decision Support System for Exposure and Risk Assessment with several assumptions. In the crater-formed-area(Ac), the non-carcinogenic risks(i.e., HI values) of TNT(Tri-Nitro-Toluene) and Cd were slightly larger than 1, and for RDX(Royal Demolition Explosives), over 50. The total non-carcinogenic risk of the whole gunnery range calculated to a significantly high value of 62.5. Carcinogenicity of Cd was estimated to be about $10^{-3}$, while that of Pb was about $5\;{\times}\;10^{-4}$, which greatly exceeded the generally acceptable carcinogenic risk level of $10^{-4}{\sim}10^{-6}$. The risk assessment results suggest that an immediate remediation practice for both carcinogens and non-carcinogens are required before the reservoir construction. However, for more accurate risk assessment, more specific estimations on condition shifts due to the construction of the reservoir are required, and more over, the effects of the pollutants to the ecosystem is also necessary to be evaluated.

• Journal of Soil and Groundwater Environment
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• v.10 no.5
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• pp.1-10
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• 2005

Policies of the United States, the United Kingdom, the Netherlands, Germany and Denmark were compared and analyzed on risk assessment of contaminated sites. These countries were chosen from a feasible preliminary analysis of 18 countries of the European Union and the U. S. All the countries selected met two major criteria : I) implementation of risk assessment to determine the soil contamination and remediation targets of contaminated sites, ii) use of soil guidance values and risk assessment as complementary measures to determine soil contamination. Suggested policy improvements to Korea regarding these issues include i) legislation of a rational risk assessment methodology of contaminated sites, and ii) enactment of collaboration of risk assessment with the soil guidance values. To establish effective risk assessment legislation, additional in-depth research on social, economic and long-term effects of the proposed risk assessment methodologies, as well as the mutual consent of all parties including academia, industry, and administration will be necessary. Linking risk assessment with soil guidance values would be applicable to a site contaminated where the contaminant concentration exceeds a certain soil guidance value. In parallel, application of risk assessment to a site where a contaminant concentration is naturally different such as mining sites would be plausible. The policy suggestions above are not yet conclusive due to a lack of policy implementation, and simulation. Thus, additional research on developing risk assessment methodology is needed. Nevertheless, initiation of the suggested policy would increase the efficacy of Korean policy regarding the survey and remediation of contaminated sites.

• Korean Journal of Environmental Agriculture
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• v.18 no.1
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• pp.28-34
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• 1999

This study was carried out to assess heavy metal pollution at 16 abandoned mining areas and to get basic data for phytoremediation. In most of surveyed area, there was no vegetation cover and soil reaction shows in low to moderate pH. Low CEC, low organic matter content were the general properties of these soils. Heavy metals content of these soils were exceed background level of unpolluted soil in Korea, especially Cu content was 2,634mg/kg at Jeil site, 3,415mg/kg Zn, 8.03mg/kg Cd at Yonhwa 2 site. This is far above tolerance limit In plant survey, very often observed plants were Pinus densiflora, and Rohinia psuedo-acacia in woody plant, Artemisia princeps, and Dianthus sinensis in herbs. Artemisia princeps had higher concentration of Zn, Cd and Dianthus sinensis had higher concentration than other plants. From the results, heavy metal concentration in plants and plant's ecotype properties, could be said that Artemisia princeps and Miscanthus sinensis have a potential of soil remediation plant. More studies are demanded to find the heavy metal tolerance species and to understand physiology property of tolerance plants, soil condition, climate etc., for successful soil remediation by plants.

• Environmental and Resource Economics Review
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• v.17 no.1
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• pp.165-196
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• 2008

This paper reports a quantitative meta analysis of the economic impacts of localized noxious and contaminated sites. Using either hedonic property value or stated preference methods, economists have studied the effects of contamination or noxious activities, or the benefits realized from their elimination, on real estate prices at more than 40 sites. In support of wise public and private investments in environmental quality, most of these studies aim to inform decision makers about the benefits of remediation and cleanup. Their results vary considerably, but there has been no previous systematic effort to analyze the differences and identify shared insights. This study uses established methods of meta analysis to identify points of agreement and differences in this body of literature. The studies are characterized by the type of site, modeling approach, geographic extent of impacts, data features, and other key factors that underlie their value estimates. The impact estimates are normalized as proportional effects on property values. This study attempts to discover whether the estimated economic impacts of contamination or noxious activity differ according to these characteristics of the studies, and whether anything general can be said about the economic consequences of site contamination and remediation. Bivariate, multivariate, and logit techniques are applied to the data. The results suggest that the property value is the most sensitive to water base contamination, published case studies result in systematically greater environmental value than those in unpublished reports, and real estate markets show responses to environmental condition changes.