• Journal of Soil and Groundwater Environment
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• v.17 no.5
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• pp.20-30
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• 2012

In case of analyzing PAHs (EPA 16 compounds) in oil-contaminated soils, the lump of peaks may occur because of the aliphatic and polar compounds in oil. This phenomenon is due to the lower accuracy of the analysis. To solve this problem, evaluation of application of silicagel-alumina multi-layer fraction was performed using standard substances and oil-contaminated soils. As a result of application of silicagel-alumina multi-layer fraction cleanup method using standard substances, recovery rates of surrogate standards (5 compounds including Naphthalene-d8) were 83~100% and those of target standards were 75~129%. These were to meet the target values (60~130%) in this study. When used 4% water-silicagel column analyze PAHs in oil-contaminated soils, Some problems were generated for quantitative analysis of PAHs; concentration of PAHs was underestimated due to an upward baseline of internal standard (recovery rate: less than 60%) and overestimated by the lump of peaks which were not purified (the biggest recovery rate: more than 400%). On the other hand, in case of silicagel-alumina multi-layer fraction cleanup method, recovery rate of surrogate standards were 61~101.6%. Therefore this cleanup method was considered a valid method to improve accuracy of analysis of PAHs in oil-contaminated soils.

• Journal of Soil and Groundwater Environment
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• v.15 no.1
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• pp.57-65
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• 2010

Currently, the pursuit of industrialization for rapid economic growth has led to serious environmental damage and related problems because of comtamination with chemicals. Over time, this contaminaion is getting worse and worse. Most developing countries have tried to pursue their economic development and growth, however without preparation for the control and disposal of hazardous wastes. Permitting hazardous waste to be abandoned and disposed in appropriately causes soil pollution, groundwater contamination, and surface water contamination, which are all extremely serious. In particular, when hazardous wastes which include toxic chemicals are distributed around the living environment even in small amounts, concentration can occur in the food chain through ecological systems, which can therefore affect human. Chromium(VI) has contaminated soil in China. We experimented to test the immobilization, chemical reduction, and soil washing methods in order to make our experiment efficient in the purification of soil contaminated with Chromium(VI), and to prove the theoretical models by experiments testing the field applications. The field experiment showed that result of experiment satisfied with the standards of China. The result of multi-stage continuous remediation reduce the Chromium(VI) concentration to 11.95 mg/kg and 14.83 mg/kg that were equivalent to 98% and 97% removal rates. This result implied we could apply multi-stage process of Chromium(VI) contaminated soil to meet the regulatory limit of Chromium(VI).

• Journal of Korea Soil Environment Society
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• v.3 no.3
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• pp.11-20
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• 1998

The effects of soil venting on the leaching potential of residual gasoline were characterized by applying a simple multi-component volatilization/dissolution model based on Raoult's law. The validity of Raoult's law in describing dissolution of gasoline was evaluated separately using both pure gasoline and gasoline contaminated soil. The aqueous concentrations of gasoline components equilibrated with pure gasoline could be described by Raoult's law within one order of magnitude, regardless of the composition of the gasoline. The leaching concentrations from contaminated soil could be well predicted at a relatively high gasoline concentration in soil. However, after 93.5% removal of gasoline by venting, the calculated values were higher than the experimental values by 50∼100%. A model involving multi-component evaporation and dissolution was applied and the results were compared with the experimental values. Possible causes of the discrepancy between the predicted values and experimental values were given.

• Journal of Environmental Science International
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• v.26 no.8
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• pp.955-966
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• 2017

Amendment of multi-binders was employed for the immobilization of metal(loid)s in field-contaminated soils to reduce the leaching potential. The effect of different types of multi-binders (lime/diammonium phosphate, diammonium phosphate/ladle slag and lime/ladle slag) on the solidification/stabilization of metal(loid)s (Pb, Zn, Cu and As) from the smelter soil and mine tailing soil were investigated. The amended soils were evaluated by measuring Toxicity Characterization Leaching Procedure (TCLP) leaching concentration of metal(loid)s. The results show that the leaching concentration of metal(loid)s decreased with the immobilization using multi-binders. In terms of TCLP extraction, the mixed binder was effective in the order of lime/ladle slag > diammonium phosphate/ladle slag > lime/diammonium phosphate. When the mixed binder amendment (0.15 g lime+0.15 g ladle slag for 1g smelter soil and 0.05 g lime+0.1 g ladle slag for 1 g mine tailing soil, respectively) was used, the leaching concentration of metal(loid)s decreased by 90%. However, As leaching concentration increased with diammonium phosphate/lime and diammonium phosphate/ladle slag amendment competitive anion exchange between arsenic ion and phosphate ion from diammonium phosphate. The Standard, Measurements and Testing programme (SM&T) analysis indicated that fraction 1 (F1, exchangeable fraction) decreased, while fraction 4 (F4, residual fraction) increased. The increased immobilization efficiency was attributed to the increase in the F4 of the SM&T extraction. From this work, it was possible to suggest that both arsenic and heavy metals can be simultaneously immobilized by the amendment of multi-binder such as lime/ladle slag.

• Journal of Soil and Groundwater Environment
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• v.15 no.5
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• pp.1-7
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• 2010

Electrokinetic technology was applied to remediate Cu, Pb and As-contaminated paddy soil. Removal of metal is highly dependent on the processing fluid during electrokinetic treatment. Tap water, NaOH, $HNO_3$, $Na_2EDTA$, and citric acid were evaluated as the processing fluids to enhance metal removal. Cu and Pb were transported toward cathode, however, it did not removed from soil section, while 56.6% of As was removed at a acidic condition. The strong acidic condition with nitric acid as a processing fluid enhanced the desoprtion of As from soil surface. However, longer operation time is needed to get the higher removal of Cu and Pb, and the acidification of soil after electrokinetic treatment should be solved.

• Journal of Soil and Groundwater Environment
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• v.21 no.6
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• pp.101-113
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• 2016

To properly manage and remediate groundwater contaminated with chlorinated hydrocarbons such as trichloroethylene (TCE), it is necessary to assess natural attenuation processes of contaminants in the aquifer along with investigation of contamination history and aquifer characterization. This study evaluated natural attenuation processes of TCE at an industrial site in Korea by delineating hydrogeochemical characteristics along the flow path of contaminated groundwater, by calculating reaction rate constants for TCE and its degradation products, and by using geochemical and reactive transport modeling. The monitoring data showed that TCE tended to be transformed to cis-1,2-dichloroethene (cis-1,2-DCE) and further to vinyl chloride (VC) via microbial reductive dechlorination, although the degree was not too significant. According to our modeling results, the temporal and spatial distribution of the TCE plume suggested the dominant role of biodegradation in attenuation processes. This study can provide a useful method for assessing natural attenuation processes in the aquifer contaminated with chlorinated hydrocarbons and can be applied to other sites with similar hydrological, microbiological, and geochemical settings.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.15 no.2
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• pp.41-56
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• 2012

Landscape space can and should play as a multi-functional agent : healing contaminated soil, reducing natural hazards, supporting living things, making comfortable environment for human, and appealing to human aesthetics, etc. This article aims to show the possibility and role of landscape space as such agent. In landscape design for National Marine Biology Resource Institute, distributed rain water treatment system and rain gardens are introduced to replace a mono-functioning large detention pond which was suggested by disaster impact assesment. Phytoremediation and vegetation filtering system with muti-cell wetlands are also adapted to heal the contaminated soil. This kind of landscape as a 'living machine' which can play as an operational control utility of multi-environment and thus can be combined effectively into green infrastructure is important for post-industrial city, especially in an era of climate change.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.334-337
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• 2002

The drinking water industry faces a growing number of difficultiesin the treatment of groundwater for drinking water production. Groundwater sources are frequently contaminated with nitrates and phosphates due to usage of chemical fertilizer In this study, feasibility of micellar enhanced ultrafiltation (MEUF) was investigated to remediate groundwater contaminated with nitrate and phosphate. Ultrafiltration membrane was cellulose acetate with molecular weight cut off (MWCO) 10,000 and celtyl pyridinium chloride (CPC) was used to form pollutant-micelle complex with nitrate and phosphate. The results show that nitrate and phosphate rejections are satisfactory. The removal efficiency of nitrate and phosphate show 80% and 84% in single pollutant system, respectively with 3 molar ratio of CPC to pollutants. In the multi-pollutant systems, the removalefficiency increased to 90 % and 89 % for nitrate and phosphate, respectively, The presence of nitrate in the solutions did not affect the removal of phosphate and that of phosphate did not affect the removal of nitrate. The concentration of CPC in the permeate and removal efficiency of CPC was a function of the concentration of CPC in the feed solutions.

• Journal of Soil and Groundwater Environment
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• v.13 no.5
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• pp.81-87
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• 2008

In accompany with the transfer of US army bases, recent surveys reported serious contamination of soils by the release of petroleum from storage facilities and heavy metals accumulated in rifle-ranges. These problems have made an increased concerns of cleanup technology for contaminated soils. In this study, a full-scale soil washing process improved by multistage continuous desorption and agitational desorption techniques was examined for petroleum-contaminated soils obtained from three different remedial sites that contained 29.3, 16.6, and 7.8% of silt and clay, respectively. The initial concentrations of total petroleum hydrocarbon (TPH) were 5,183, 2,560, and 4,860 mg/kg for each soil. Pure water was applied to operate washing process, in which water used for washing process was recycled 100% for over 6 months. The results of full-scale washing tests showed that the TPH concentrations for soils (> 3.0 mm) were 50${\sim}$356 mg/kg (85.2${\sim}$98.2% removal rates), regardless of the contents of silt and clay from in A, B and C soil, when the soils were washed at 3.0 kg/$cm^2$ of injection pressure with the method of wet particle separation. Based on the initial TPH concentration, the TPH removal rates for each site were 85.2, 98.2 and 89.9%. For soils in the range of 3.0${\sim}$0.075 mm, the application of first-stage desorption technique as a physical method resulted 834, 1,110, and 1,460 mg/kg of TPH concentrations for each soil, also additional multi-stage continuous desorption reduced the TPH concentration to 330, 385, and 245 mg/kg that were equivalent to 92.4, 90.6, and 90.1% removal rates, respectively. The result of multi-stage continuous desorption for fine soil (0.075${\sim}$0.053 mm) were 791, 885, and 1,560 mg/kg, and additional agitation desorption showed 428, 440, and, 358 mg/kg of TPH concentrations. Compared with initial concentration, the removal rates were 92.0, 93.9 and 92.9%, respectively. These results implied we could apply strategic process of soil washing for varies types of contaminated soils to meet the regulatory limit of TPH.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.09a
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• pp.79-82
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• 2001

Analytical solutions have been derived to delineate the capture zone created by pumping wells for the remediation design of contaminated groundwater. These previous analytical solutions are often restricted to pumping wells only, specific well locations, a limited number of wells, and an isotropic aquifer. Analytical solution was developed to deal with arbitrarily located multi injection-pumping wells in an anisotropic homogeneous aquifer. The solution presented in this study provides a simple, easy method for determining tile complex flow field caused by multi injection-pumping wells at different rates, and will consequently be useful in pump-and-treat design.