• Journal of Korean Society on Water Environment
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• v.21 no.4
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• pp.403-409
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• 2005

Methyl tert-butyl ether (MTBE) contamination in groundwater often coexists with benzene, toluene, ethylbenzene, and xylene (BTEX) near the source of the plume. Then, groundwater contamination problems have been developed in areas where the chemical is used. Common sources of water contamination by BTEX and MTBE include leaking underground gasoline storage tanks and leaks and spills from above ground fuel storage tanks, etc. In oil-contaminated environments, anaerobic biodegradation of BTEX and MTBE depended on the concentration and distribution of terminal electron acceptor. In this study, effect of electron acceptor on the anaerobic biodegradation for BTEX and MTBE-contaminated soil was investigated. This study showed the anaerobic biodegradation of BTEX and MTBE in two different soils by using nitrate reduction, ferric iron reduction and sulfate reduction. The soil samples from the two fields were enriched for 65 days by providing BTEX and MTBE as a sole carbon source and nitrate, sulfate or iron as a terminal electron acceptor. This study clearly shows that degradation rate of BTEX and MTBE with electron acceptors is higher than that without electron acceptors. Degradation rate of Ethylbenzene and Xylene is higher than that of Benxene, Toluene, and MTBE. In case of Benzene, Ethylbenzene, and MTBE, nitrate has more activation. In case of Toluene and Xylene, sulfate has more activation.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.4
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• pp.90-96
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• 2003

This study was performed to evaluate effect of extraction mode on SVE efficiency for fuel-contaminated soil. A gas station was selected for this study. As a result of pressure test in well head, soil texture of contaminated site under the gas station was very different from site to site. SVE system was operated in intermittent mode (1hr extraction / 3hr rest) or continuous mode. Capacity of air blower was $1m^3/min$. Extration mode test was conducted in two severe contaminated sites. In both two sites, cumulative TPHgas mass of intermittent extraction mode was higher than that of continuous mode. Considering long term operation of SVE in a field, in general, it was thought that intermittent extraction mode was effective in view of vaporized TPHgas mass and electrical cost.

• Journal of Soil and Groundwater Environment
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• v.15 no.2
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• pp.24-33
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• 2010

This study focused on the groundwater quality, biodegradability and attenuation rate at the petroleum contaminated sites of Kangwon and Gyeonggi Provinces, Korea. For groundwater quality, Kangwon site showed chemical compositions of $Ca-SO_4+Cl$, $Ca-HCO_3$ and $Na+K-HCO_3$ types, while Gyeonggi site showed chemical compositions of $Ca-SO_4$, $Ca-HCO_3$ and $Na-HCO_3$ types. $Na+K-HCO_3$ and $Na-HCO_3$ types were detected only in February. Among many biodegradation processes, the majority was attributed to biodegradation from denitrification in both area. In Kangwon site, biodegradation from denitrification occupied 63.5%, and in Gyeonggi site it was 39.45%. Biodegradation from the most efficient aerobic respiration occupied 7.12% in Kangwon site, while Gyeonggi site in it did 27.29%. Point attenuation rate of BTEX in Gyeonggi site (GW-22) was 0.0182 $day^{-1}$, half life of BTEX was 84 days, and thus 124 days (0.34 year) would be required to clean up this site. Mean of point attenuation rate of TPH in Kangwon site was 0.0088 $day^{-1}$, mean of half life was 257 days, and thus 462 days would be required to clean up the site. Mean of point attenuation rate of TPH in Gyeonggi site was 0.0387 $day^{-1}$, mean of half life was 55 days, and thus remediation time was calculated as 99 days.

• Journal of Environmental Impact Assessment
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• v.8 no.2
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• pp.31-44
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• 1999

Atmospheric dry deposition flux and ambient particle mass size distribution were measured to evaluate the impact of atmospheric deposition around the Nanjido landfill sites. Wind direction affects greatly on the variation of mass flux and mass size distribution and made two times higher when the wind was blown from the road side. The effect of Nanjido landfill on the mass size distribution was significant comparing to simultaneously measured mass size distribution at the other sampling site. The results showed that the particle diameter bigger than $10{\mu}m$ explained the majority of atmospheric dry deposition flux. A survey was also carried out to investigate the contamination of soils in a completed Nanjido landfill. The chemical properties of the soil analyzed in the present study include pH, oxidation-reduction potential (ORP), anion and cation concentration, total organic carbon(TOC), and some-metal elements concentrations were analyzed. Microbial activity in the soils was also evaluated by measuring dehydrogenase activities. TOC in the soil contaminated with leachate was $467.0{\mu}g/g-dry$ soil, and the TOC in the soil, where Nanjido landfill gases were emitted from, was $675{\mu}g/g-dry$ soil. The highest microbial activity of $968.0{\sim}2147{\mu}g-TPF/g-dry$ soil day was found in the soil spouting Nanjido landfill gases. Compared with those in the uncontaminated soil, the concentrations of Cr, Cu and Ph in the contaminated soil were higher.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.473-479
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• 2014

In this study, chemical characteristics of groundwater around carcass burial areas and those in agricultural and livestock-farming complex areas in South Korea were monitored. Groundwater samples were collected from 166 wells around carcass burial sites and 466 wells around the agricultural areas where carcass burial sites are absent. The chemical parameters (pH, electrical conductivity, dissolved oxygen, oxidation reduction potential, $NO_3$-N, $NH_4$-N, and $Cl^-$) in carcass burial areas and agricultural areas were similar. The $NO_3$-N concentrations exhibited minimal seasonal fluctuations below $30mg\;L^{-1}$ in most of the wells, even in the wells located close to the carcass burial sites; and $Cl^-$ concentrations also showed similar patterns. The chemical characteristics of groundwater monitored in this study indicated that groundwater was widely contaminated by agricultural activities and livestock farming, but probably not by leachates derived from nearby carcass burial sites.

• Korean Journal of Environmental Agriculture
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• v.33 no.2
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• pp.78-85
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• 2014

BACKGROUND: Recent studies using various industrial wastes for heavy metal stabilization in soil were conducted in order to find out new alternative amendments. The acid mine drainage sludge(AMDS) contains lots of metal oxides(hydroxides) that may be useful for heavy metal stabilization not only waste water treatment but also soil remediation. The aim of this study was to investigate the applicability of acid mine drainage sludge for heavy metals stabilization in soils METHODS AND RESULTS: Alkali soil contaminated with heavy metals was collected from the agricultural soils affected by the abandoned mine sites nearby. Three different amounts(1%, 3%, 5%) of AMDS were applied into control soil and contaminated soil. For determining the changes in the extractable heavy metals, $CaCl_2$ and Mehlich-3 were applied as chemical assessments for metal stabilization. For biological assessments, lettuce(Lactuca sativa L.) and chinese cabbage(Brassica rapa var. glabra) were cultivated and accumulation of heavy metals on each plant were determined. It was revealed that AMDS reduced heavy metal mobility and bioavailability in soil, which resulted in the decreases in the accumulation of As, Cd, Cu, Pb, and Zn in each plant. CONCLUSION: Though the high level of heavy metal concentrations in AMDS, any considerable increase in the heavy metal availability was not observed with control and contaminated soil. In conclusion, these results indicated that AMDS could be applied to heavy metal contaminated soil as an alternative amendments for reducing heavy metal mobility and bioavailability.

• Journal of Soil and Groundwater Environment
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• v.20 no.4
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• pp.8-14
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• 2015

Plants grown in metal-contaminated sites have to be managed and disposed of safely even in phytoremediation because heavy metals can be transferred to other organisms through the food chain, which could result in bioaccumulation in organisms of a higher trophic level. However, if the harvested plants could be used for bioenergy, the ecological risk is reduced and phytoremediation improves economic feasibility. This study researched the effects of EDDS (Ethylenediamine disuccinate) on the heavy metal uptake performance of Brassica campetris and Sorghum biocolor, both of which have potential as bioenergy plants. The results showed that EDDS could increase Pb, Cu, Ni, Cd, and Zn concentrations in the roots and shoots of both of these plants. Furthermore, EDDS reduced the metal inhibition of the S. bicolor length growth. The translocation factors (TF) of S. bicolor and B. campestris are smaller than one for all five heavy metals tested and decreased by the following order: heavy metal + EDDS > heavy metals only > uncontaminated soil. The results suggest that with regard to plant growth and metal accumulation, S. bicolor treated with EDDS is more suitable than is B. campestris for the phytoremediation of soils contaminated with multiple metal species.

• Journal of Microbiology and Biotechnology
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• v.15 no.2
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• pp.337-345
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• 2005

The degradation of phenanthrene, a model PAH compound, by microorganisms either in the mixed culture or individual strain, isolated from oil-contaminated soil in oil refmery vicinity sites, was examined. The effects of pH, temperature, initial concentration of phenanthrene, and the addition of carbon sources on biodegradation potential were also investigated. Results showed that soil samples collected from four oil refinery sites in Korea had different degrees of PAH contamination and different indigenous phenanthrene-degrading microorganisms. The optimal conditions for phenanthrene biodegradation were determined to be 30$^{circ}C$ and pH 7.0. A significantly positive relationship was observed between the microbial growth and the rate of phenanthrene degradation. However, the phenanthrene biodegradation capability of the mixed culture was not related to the degree of PAH contamination in soil. In low phenanthrene concentration, the growth and biodegradation rates of the mixed cultures did not increase over those of the individual strain, especially IC10. High concentration of phenanthrene inhibited the growth of microbial strains and biodegradation of phenanthrene, but was less inhibitory on the mixed culture. Finally, when non-ionic surfactants such as Brij 30 and Brij 35 were present at the level above critical micelle concentrations (CMCs), phenanthrene degradation was completely inhibited and delayed by the addition of Triton X100 and Triton N101.

• Journal of Soil and Groundwater Environment
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• v.10 no.4
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• pp.1-12
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• 2005

Policies regarding to soil quality of the United States, the United Kingdom, the Netherlands, Germany, and Demark were analyzed to suggest Korean policy for improving soil quality concept and it's implementation. All countries met four criteria: I) Soil quality levels of contaminants are indebt to concept of contaminant risk to recipients (human and ecosystem); ii) Any soil quality value can't be a magic number to determine whether a site is contaminated or not. To determine risk of sites, risk assessment of the sites should be followed; iii) Concentrations of contaminants of sites are not always significantly certain to risk of human and ecosystem of the sites; and iv) Soil quality levels are adopted based on land uses and plans. Considering our rooms to improve policies and analysis of the other country reports on their legislations about soil quality levels, our policy implementation could be approached from these directions: i) Our concept for soil quality levels needs to develop in scientific and rational. ii) Soil quality levels and risk assessment should be implemented as determining tools of site contamination in parallel, and iii) Soil quality levels depending on land uses and plans should be developed in debt with rational and scientific concept of risk. Increasing efficacy of Korea policy regarding the soil quality levels would be in dept to applying concepts of SCL (Soil Contamination Level) and SRL (Soil Regulatory Level) developed, implementing soil quality levels and risk assessment of contaminated sites in conjunction, and classifying three distinctions of land uses based on sensitiveness of recipients (human and ecosystem) to contaminants in soil in this research.

• Journal of Soil and Groundwater Environment
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• v.26 no.6
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• pp.27-35
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• 2021

This study examined the possibility of reutilization of soil reclaimed from contaminated sites after completing remediation. The current status of soil remediation methods in Korea was reviewed and physicochemical properties of soil before and after remediation processes were examined to access the recycling possibility of reclaimed soils based on Recycling Aggregate Quality Standard. The most commonly practiced soil remediation techniques are soil washing, land farming, and thermal desorption. These techniques tend to deteriorate various soil properties including electrical conductivity(EC), organic matter content(OM), available P₂O₅, and cation exchange capacity(CEC). Evaluation of the properties of soil retrieved after each remediation process indicated soil washing may yield the most suitable soil for use as a filling, covering, back-filling, road pavement, and blocking materials, In addition, the soils reclaimed from land farming and thermal desorption have potential utility as a filling, covering and road pavement materials.