• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.22-25
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• 2002

The effect of in-situ chemical oxidation on the indigenous soil microorganisms (total microbes and PAH-degrading microbes) and contaminant removal were investigated. Field soil contaminated with diesel in gas station was collected and the soil was treated from 0 to 900 minutes by in-situ ozonation as chemical remediation. The treated soil samples were incubated with supplying oxygen during the 9 weeks to understand the characteristics of microbes regrowth, damaged by ozone. The sharp decrease of aromatic fraction and TPH was observed within 60 minutes of ozone application and aromatic fraction and TPH then slowly decreased. The phenanthren-degrading bacteria were the most sensitive to ozonation, because 1 hour of ozonation reduced the microbes from 10$^{6}$ CFU/g-soil to below detection limits.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.258-261
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• 2004

In this study, the combined electrokinetic and ultrasonic remediation technique onto simple soil flushing was studied for the enhancement of water and liquid flows and the removal of contaminants in contaminated soils. The ultrasonic technique has been used to increase liquid flow and remove pollutants in contaminated soil. The laboratory soil flushing tests combined electrokinetic and ultrasonic technique were conducted using specially designed and fabricated devices to determine the effect of these both techniques. A series of laboratory permeability experiments involving the simple, electrokinetic, ultrasonic, and electrokinetic & ultrasonic flushing test were carried out. A soil admixed with sand and kaolin was used as a test specimen, and Pb and ethylene glycol were used as contaminants. An increase in out flow, permeability and contaminant removal rate was observed in electrokinetic and ultrasonic flushing tests.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.275-278
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• 2002

In this study, to increase removal efficiency of traditional electrokinetic treatment and to reduce contaminant load of wastewater that discharged through cathode compartment, enhanced electrode compartments were investigated. Hydroxide precipitation near the cathode electrode that encounter during traditional electrokinetic treatment were prevented by enhanced electrokinetic remediation test with newly invented electrode compartment. And heavy metal concentration in wastewater showed 0 ppm thus, additive post-treatment cost were not needed.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.99-101
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• 2003

Unsaturated hydraulic conductivity models have been widely used for the numerical modeling of water flow and contaminant transport in soils. In this study, a simple hydraulic conductivity model is developed by using information of particle-size distribution from the lognormal distribution model and its results are compared with those from the Kosugi-Mualem (KM) model. The accuracy of the proposed model is verified for observed data chosen from the international UNSODA database. Results showed that the proposed model produces adequate predictions of hydraulic conductivities. Performance of this model is generally better than the KM function.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.24-27
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• 2002

The optimal designs of groundwater problems of contaminant containment and cleanup using linear programming and genetic algorithm are provided. In the containment problem, genetic algorithm shows the superior feature to linear programming. In cleanup problem, genetic algorithm makes reasonable optimal design. Un this study, it is demonstrated through numerical experiments that genetic algorithm can be applied to remedial designs of groundwater problems.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.199-202
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• 2004

In this study the field-scale tests were performed in which in-situ E/K remediation technologies were applied, and then the results were present. For traditional E/K remediation method the efficiency of remediation is not large, but the enhanced method with citric acid significantly increases the removal efficiency. Also EDTA, reported as a good enhancement agent for removal of heavy metals, is similar to that of citric acid. Therefore citric acid is preferred rather than EDTA in view of the cost on the contaminant removal per unit concentration.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.302-306
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• 2000

In case of applying electrokinetic remediation, magnitude of electric current is one of major factors for estimation of contaminant transport. In practice, electric current provide determination of electric conductivity based on specimen resistance. Electric current variation is produced during Electrokinetic remediation test. Electric current is decreased by expotential function according to time in condition of constant voltage. This can be interpreted as precipitation effect by OH$^{-10}$ generation in a cathode.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.03a
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• pp.739-742
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• 2002

Immobilization of contaminants in contaminated soils by solidification processes is an attractive potential remediation process. In this study, the treatability of lead, copper, toluene, and COD was investigated by leaching test. Industrial sand was adopted as the test material and was contaminated with lead copper, and toluene to 100mg/kg, 500mg/kg, 200mg/kg respectively. P solidifying agent was used as the binder(20% by weight of contaminated soil) in the solidification treatment. The leachability of contaminants leached from the solidified soil was evaluated using column test. The percentage of contaminants leached from the solidified soil was significantly reduced by reaction of waste species with cement components and encapsulation reaction of binder. Based on the tests, it is ascertained solidification process can be a very effective method to control the elution of contaminants from the contaminated soil.

• Journal of Korea Soil Environment Society
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• v.3 no.2
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• pp.71-78
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• 1998

Pyrene is a common petroleum contaminant. This compound is recalcitrant to biological degradation and persists long in contaminated environments. A microcosm experiment was conducted to investigate the degradation rate of pyrene in three different of soil : rhizosphere soil ; non-rhizosphere soil ; and sterilized soil. The degradation rate followed the order of rhizosphere soil)non-rhizosphere soil)sterilized soil. And the rate did not change significantly when organic acids commonly found in the rhizosphere were added to each soil but it seemed to be well related to the increase of the number of microorganisms. Overall, it appears that pyrene is degraded faster in the rhizosphere soil which has the higher microorganism density.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2009.10a
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• pp.57-60
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• 2009