• Journal of the Korean Geotechnical Society
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• v.18 no.1
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• pp.49-57
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• 2002

During the electrokinetic remediation, direct current applied to a soil-water-electrolyte system derives the variations of fluid transport phenomena in soil-water system and soil-water interface characteristics. Therefore, these variations affect the electrokinetic reaction. In this study, lab-scale electrokinetic remediation tests were performed to characterize the electrical and chemical parameters variation in soil. During the test, voltage gradient, electrical current, zeta potential and pH variations were measured. On the basis of experimental results, computer modeling techniques predicting the variations of these parameters are suggested.

• Economic and Environmental Geology
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• v.37 no.1
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• pp.99-106
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• 2004

Pollution reduction and/or control technology becomes one of the pressing post-semiconductor research field to lead an advanced industrial structure. Soil/groundwater remediation techniques may act as a core technology which will create many demands on pollution reduction areas. A plenty numbers of abandoned metal mines were left without any remediation action in Korea, and it may be potential sources of heavy metal and As contamination in the ecosystem. In order to bring this soil contamination to a settlement, the emerging soil/groundwater remediation techniques should be introduced. Main research topics in the United States and Europe move towards the clean remediation technology without any secondary impact and the feasible application of developing technique into the field scale study. With these advantages, several soil/groundwater techniques such as electrokinetic soil processing, permeable reactive barrier, stabilization/solidification, biosorption, soil flushing with biosurfactant, bioleaching and phytoremediation will be summarized in this paper.

• Journal of Korea Soil Environment Society
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• v.4 no.3
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• pp.3-15
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• 1999

This paper includes the basic experimental results performed for developing an innovative and technologically feasible process wherein gaseous ozone, a powerful oxidant. is injected directly into vadose zone by which in-situ chemical degradation of semi- or, non-volatile petroleum product such as diesel fuel is derived. As ozone gas injected continuously(50mL/min, 119.0$\pm$6.1mg/L) into soil packed columns artificially contaminated with diesel fuel(initial concentration 1,485mg-DRO/kg/soil), the removal rates at the inlet and outlet point of 14hrs-operated column are 87.9% and 100.0%, respectively. On the other hand, soil vapor extraction system showed less than 30% of removal rates of residual diesel both at the inlet and outlet samples under the same experimental conditions which confirms the limited treatability of SVE in diesel contaminated soil.

• Journal of the Korean Chemical Society
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• v.66 no.4
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• pp.269-277
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• 2022

In recent years, carbon-based catalysts have become a research hotspot in environmental governance applications. Carbon-based catalysts have large surface areas, porous structures, multi-surface functional groups and excellent electron transfer capabilities, and can synergistically exhibit adsorption and catalytic performance. This article reviews the research progress of carbon-based catalysts in environmental governance, mainly including its application in wastewater treatment, exhaust gas purification and soil remediation. In view of the current difficulties in the research of carbon-based catalysts, the development prospects are proposed. We hope that this review will provide convenience for new entrants and researchers intending to employ carbon-based catalysts for the remediation of contaminated environment.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.131-134
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• 2004

Several physical and chemical methods have been used for remediation contaminated by oils. However the cost was very high and secondary pollution rose during treating. The purpose of this study was to comprision TPH (total petroleum hydrocarbon) removal from artificially contaminated soil by diesel with and without seeding anaerobic digested sludge. After 120 days of overall at 35$^{\circ}C$, removal efficiency of TPH with seeding sludge was 2-3 times higher than blank. Also, the more amount seeding sludge, TPH removal efficiency and CH$_4$ content more obtained. It was sad that seeding of anaerobic digested sludge was a good method for enhancing TPH removal efficiency without increasing operating cost. Sulfate, nitrate-reducing, methanogenic condition were evaluated for alkane, isoprenoid as target contaminated soil.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.22 no.2
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• pp.159-171
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• 2024

This study aimed to develop an efficient recycling process for wastewater generated from soil-washing used to remediate uranium (U(VI))-contaminated soil. Under acidic conditions, U(VI) ions leached from the soil were precipitated and separated through neutralization using hydrazine (N₂H₄). N₂H₄, employed as a pH adjuster, was decomposed into nitrogen gas (N₂), water (H₂O), and hydrogen ions (H⁺) by hydrogen peroxide (H₂O₂). The residual N₂H₄ was precipitated when the pH was adjusted using sulfuric acid (H₂SO₄) to recycle the wastewater in the soil-washing process. This purified wastewater was reused in the soil-washing process for a total of ten cycles. The results confirmed that the soil-washing performance for U(VI)-contaminated soil was maintained when using recycled wastewater. All in all, this study proposes an efficient recycling process for wastewater generated during the remediation of U(VI)-contaminated soil.

• Journal of Soil and Groundwater Environment
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• v.26 no.5
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• pp.9-19
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• 2021

This study evaluated the feasibility of combined use of physical separation and soil washing to remediate heavy metals (Pb and Cu) contaminated soil in a military shooting range. The soils were classified into two types based on the level of heavy metal concentrations: a higher contaminated soil (HCS) with Pb and Cu concentrations of 6,243 mg/kg and 407 mg/kg, respectively, and a lower contaminated soil (LCS) with their concentrations of 1,658 mg/kg and 232 mg/kg. Pb level in both soils exceeded the regulatory limit (700 mg/kg), and its concentration generally increased with decreasing soil particle size. However, in some cases, Pb concentrations increased with increasing soil particle size, presumably due to the presence of residues of bullets in the soil matrix. As a pretreatment step, a shaking table was used for physical separation of soil to remove bullet residues while fractionating the contaminated soils into different sizes. The most effective separation and fractionation were achieved at vibration velocity of 296 rpm/min, the table slope of 7.0°, and the separating water flow rate of 23 L/min. The efficiency of ensuing soil washing process for LCS was maximized by using 0.5% HCl with the soil:washing solution mixing ratio of 1:3 for 1 hr treatment. On the contrary, HCS was most effectively remediated by using 1.0% HCl with the same soil:solution mixing ratio for 3 hr. This work demonstrated that the combined use of physical separation and soil washing could be a viable option to remediate soils highly contaminated with heavy metals.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.306-309
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• 2002

Micellar-enhanced ultrafiltration was investigated to remediate groundwater contaminated with chromate using a cationic surfactant, cetylpyridinium chloride (CPC). Removal of chromate was expressed as a function of molar ratio of CPC to chromate. With 10 molar ratio of CPC, removal efficiency of chromate was reached to over 99%. The rejection of CPC was 90% at 1 molar ratio, gradually increased as the molar ratio increased.

• Journal of Environmental Policy
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• v.3 no.2
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• pp.31-57
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• 2004

Attempts were made to compare and analyze the policies of the United States, the United Kingdom, the Netherlands, Germany and Denmark concerning Korea's major problems associated with legal liability of the contaminated sites. These countries were chosen from a feasible preliminary analysis of 18 countries of the EU and the U. S. The major problems were revealed based on the analysis of Korean legacy and legislation, which are summarized as follows i) lack of clear detailed technical and legal guidance to determine the responsible party or parties of contaminated sites, ii) no distinction between the strict and non strict legal liability of innocent land owners, iii) no clearly set limit on retroactive legal liability. Comparison of the policies of countries chosen suggested improvements regarding these major problems as follows: i) activating national and international research on soil contamination prevention policy, ii) arranging distinct legal regulation between strict and non strict liability criteria, iii) establishing the limits on innocent and non strict liability, iv) establishing methodology and process of legal liability distribution and compensation, and v) establishing a legal process to redeem any benefit derived from remediation of contaminated sites with the public budget. Our policy suggestions above are not yet conclusive due to a lack of policy implementation simulation. Additional research is needed on aspects of social, economic and long term effects of the proposed policy directions. Nevertheless, application of the policy suggestions of this research would increase the efficacy of Korean policy regarding the survey and remediation of the potentially contaminated sites.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.10a
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• pp.593-596
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• 2002

This study examined the feasibility of Electrokinetic-Fenton process for remediation of contaminated kaolinite by phenanthrene. The test using 7% H$_2$O$_2$as anode purging solution indicated the higher electrical current and electroosmotic flow than the test using 3.5% H$_2$O$_2$. And distribution in the soil of H$_2$O$_2$concentration showed the higher value of the former than the latter. Furthermore, the test using 7% H$_2$O$_2$and 0.01N H$_2$SO$_4$was the highest electrical current and electroosmotic flow and H$_2$O$_2$was effectively introduced to the cathode region. As it turned out, the treatment effect of phenanthrene was improved in compare with the other tests.