• Journal of Soil and Groundwater Environment
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• v.18 no.6
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• pp.8-17
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• 2013

The contamination of chlorinated ethenes at an industrial complex, Wonju, Korea, was examined based on sixteen rounds of groundwater quality data collected from 2009 to 2013. Remediation technologies such as soil vapor extraction, soil flushing, biostimulation, and pumping-and-treatment have been applied to eliminate the contaminant sources of trichloroethylene (TCE) and to prevent the migration of TCE plume from remediation target zones. At each remediation target zone, temporal monitoring data before and after the application of remediation techniques showed that the aqueous concentrations of TCE plume present at and around the main source areas decreased significantly as a result of remediation technologies. However, the TCE concentration of the plumes at the downstream area remained unchanged in response to the remediation action, but it showed a great fluctuation according to seasonal recharge variation during the monitoring period. Therefore, variations in the contaminant flux across three transects were analyzed. Prior to the remediation action, the concentration and mass discharges of TCE at the transects were affected by seasonal recharge variation and residual DNAPLs sources. After the remediation, the effect of remediation took place clearly at the transects. By tracing a time-series of plume evolution, a greater variation in the TCE concentrations was detected at the plumes near the source zones compared to the relatively stable plumes in the downstream. The difference in the temporal profiles of TCE concentrations between the plumes in the source zone and those in the downstream could have resulted from remedial actions taken at the source zones. This study demonstrates that long term monitoring data are useful in assessing the effectiveness of remediation practices.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.217-221
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• 2003

Variation of decision variables for optimal remediation using the pump-and-treat method is examined to estimate the effect of the degree of concentration constraint. Simulation-optimization method using genetic algorithm is applied to minimize the total pumping volume. In total volume minimization strategy, the remediation time increases rapidly prior to significant increase in pumping rates. When the concentration constraint is set severer, the more wells are required and the well on the down-gradient direction from the plume hot-spot gives more efficient remediation performance than that on the hot-spot position. These results show that the more profitable strategy for remediation can be achieved by increasing the required remediation time than raising the pumping rate until the time reaches a certain limitation level. So, the remediation time has to be considered as one of the essential decision variables fer optimal remediation design.

• Journal of Soil and Groundwater Environment
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• v.20 no.3
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• pp.7-14
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• 2015

In this study, land farming and chemical oxidation of a diesel-contaminated site is compared to evaluate the environmental impact during soil remediation using the Spreadsheet for Environmental Footprint Analysis by U.S. EPA. Each remediation process is divided into four phases, consisting of soil excavation, backfill and transportation (Phase 0), construction of remediation facility (Phase 1), remediation operation (Phase 2), and restoration of site and waste disposal (Phase 3). Environmental footprints, such as material use, energy consumption, air emission, water use and waste generation, are analyzed to find the way to minimize the environmental impact. In material use and waste generation, land farming has more environmental effect than chemical oxidation due to the concrete and backfill material used to construct land farming facility in Phase 1. Also, in energy use, land farming use about six times more energy than chemical oxidation because of cement production and fuel use of heavy machinery, such as backhoe and truck. However, carbon dioxide, commonly considered as important factor of environmental impact due to global warming effect, is emitted more in chemical oxidation because of hydrogen peroxide production. Water use of chemical oxidation is also 2.1 times higher than land farming.

• Journal of Soil and Groundwater Environment
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• v.15 no.1
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• pp.19-28
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• 2010

Considering six screen matrix to select an optimum remediation method for the Kunsan military base contaminated with petroleum oil, the following order was obtained: landfarming > biopile > soil washing > thermal desorption = incineration. When the landfarming method was applied for the remediation of 2,250 $m^3$ soil contaminated with petroleum oil ranging from 500 to 2,404 mg/kg as TPH, contamination level decreased below target concentration 450 mg/kg after 20~42 days depending on the initial contamination. From the evaluation of case studies of landfarming, it is suggested that ratty-truss or single-arch structure is suitable in the landfarming plant for the treatment of large-scale contaminated soil requiring long period of remediation. But, vinyl-house structure is suitable in the landfarming plant for the treatment of small-scale contaminated soil requiring short period of remediation. Therefore vinyl-house structure is recommended in the remediation of contaminated soil less than 5,000 $m^3$ requiring within 1 year of remediation period but ratty-truss or single-arch structure is recommended for the remediation of contaminated soil more than 5,000 $m^3$.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.590-590
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• 2005

• Journal of Soil and Groundwater Environment
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• v.27 no.4
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• pp.22-36
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• 2022

Cadmium is a class 1 carcinogen classified by the International Agency for Research on Cancer (IARC) and has a high potential for leaching into groundwater. Therefore, it is necessary to address cadmium contamination by employing adequate treatment methodologies. Although various methods have been suggested to reduce cadmium in groundwater, their applications often suffer from various limitation arising from heterogeneous field conditions and technical difficulties. In this work, several in-situ technologies to treat cadmium contaminated groundwater were reviewed and discussed by separately addressing physicochemical, chemical and biological methods. In particular, the optimum cadmium remediation strategies that involve physical removal of source area → physicochemical and chemical remediation → biological remediation were proposed by considering reduction efficiency, adsorption rate, economic feasibility and ease of field application in groundwater.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09c
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• pp.117-124
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• 2010

In the field of soil and groundwater remediation, sustainability was merged into remediation process and green remediation was initiated within the concept of sustainable development. Green remediation was defined and has been already applied to the remediation fields in U.S. In the case of Europe, green remediation has been evaluated for the application of green technology in the remediation industry and they especially defined sustainable remediation following idea of sustainable development. Although green and sustainable remediation is global trends, there are only a few cases about application of green remediation in South Korea. It is needed to develop soil and groundwater remediation technology towards green remediation, considering "Green Growth" as policy direction in South Korea.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.503-508
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• 2004

Optimal remediation design using the pump and treat(P&T) method and natural attenuation was accomplished in consideration for degradation processes, such as sorption and first-order decay rate. Variation of both sorption and first-order decay rate has influence on design of optimal remediation application. When sorption effect increases, the more pumping rate and pumping wells are required. The location of operated wells is on the centerline of contaminant plume and wells near hot spot are mainly operated when sorption effect increases. The higher of first-order decay rate, the less pumping rate is required. These results show that the degradation processes have to be considered as one of the essential factors for optimal remediation design.

• Applied Chemistry for Engineering
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• v.30 no.3
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• pp.261-279
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• 2019

The aim of this review article is to summarize the role of titanium oxide ($TiO_2$) nanomaterials in the remediation of the aquatic environment contaminated with various emerging pollutants. The advanced oxidation process led by the semiconductor $TiO_2$ is an impetus in the remediation technology. Therefore, a vast number of literature works are available in this area. Further, the role of modified $TiO_2$ or thin film materials were discussed in the review. Also, the Localized Surface Plasmon Resonance (LSPR) effect of using noble metaldoped $TiO_2$ played an interesting role in the remediation process.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.873-881
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• 2004

A serious of EK remediation tests on contaminated soil are performed under unsaturated conditions and analyzed for electrical potential, water content, pH and so on. The results indicated that electrical potential and pH distributions in the sample are dependent on the amount and inward/outward flow of hydrogen ion. Specially, for the closed system the water content is largely decreased with the flow of hydrogen. The maximum electrical conductivity is measured at the catholyte of CEM(Sealing) test and directly related to the remedial efficiency. Although pHs in the region near to the anode are similarly developed, the different concentration of lead is measured with the electrical gradient contrary to the lead concentration dependent on pH within the sample.