• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.11 no.2
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• pp.77-83
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• 2013

The original pilot-scale electrokinetic equipment suitable to soil contamination characteristics of Korean nuclear facility sites was manufactured for the remediation of soil contaminated with uranium. During the experiment with the original electrokinetic equipment, many metal oxides were generated and were stuck on the cathode plate. The uranium removal capability of the original electrokinrtic equipment was almost exhausted because the cathode plate covered with metal oxides did not conduct electricity in the original electrokinetic equipment. Therefore, the original electrokinetic equipment was improved. After the remediation experience for 25 days using the improved electrokinetic remediation equipment, the removal efficiency of uranium from the soil was 96.8% and its residual uranium concentration was 0.81 Bq/g. When the initial uranium concentration of soil was about 50 Bq/g, the electrokinetic remediation time required to remediate the uranium concentration below clearance concentration of 1.0 Bq/g was about 34 days. When the initial uranium concentration of soil was about 75 Bq/g, the electrokinetic remediation time required to remediate below 1.0 Bq/g was about 42 days. When the initial uranium concentration of soil was about 100 Bq/g, the electrokinetic remediation time required to remediate below 1.0 Bq/g was about 49 days.

• 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.4
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• pp.13-20
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• 2010

The purpose of this study was to develope the remediation method of contaminated soils with metals and petroleum. The diesel degrading strain was isolated and identified from the soil contaminated by petroleum at industrial sites. Diesel biodegradation experiment was performed by diesel degrading bacteria in both solution and soil slurry. Contaminated soils by Zn or As and diesel were treated consecutively by steam-vapor extraction, biodegradation, and acid washing. The strain was identified as Pseudomonas aeruginosa, and named as Pseudomonas aeruginosa TPH1. The optimal culture conditions of TPH1 were $20^{\circ}C$ and pH 7.0, 3% of diesel concentration. Biodegradation of diesel was performed using the separated strain in liquid medium, and 63% of diesel was degraded in 72 hours. And 52% of diesel was removed in the tested soils. In the treatment of contaminated soils with diesel and Zn or As, 29% ~ 44% of diesel was reduced by steamvapor extraction, 60% ~ 71% of diesel was removed after biodegradation. 47% of Zn and 96% of As were removed after acid(mixture of sulfuric and oxalic acids) washing. It is recommended that consecutive treatment method of steam-vapor extraction, biodegradation and acid washing is effective for remediation of complex contaminated soils with metals and petroleum.

• Journal of Soil and Groundwater Environment
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• v.16 no.3
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• pp.10-16
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• 2011

The experimental studies for remediation of diesel contaminated soils were performed using subcritical water in laboratory scale. Contaminated soils from industrial area and artificially contaminated soils were utilized for soil remediation. Experimental system was composed for subcritical water to flow upward through the soil packed column for extracting contaminants. 10 g of contaminated soil was packed into the column and water flow rate was 2 mL/min. To evaluate the effects of temperature, pressure and treatment time on the removal efficiency, temperature was changed from 100$^{\circ}C$ to 350$^{\circ}C$, pressure from 50 bar to 220 bar and treatment time at the predetermined temperature from 0 min to 120 min. The purification efficiency increased as temperature increased. However, the effect of pressure and treatment time was low. Temperature 250$^{\circ}C$, pressure 50 bar and treatment time 30 min were selected for optimal operating condition for this study.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.286-289
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• 2004

On site, In situ soil remediation technologies are very important among the remediation technologies and in general efficiency of these technologies are turned to site characterization and environmental condition. specially using of only one technology has so many limitation factors. for example, existing state of tailing and channeling and so on. actually, filled land have high concentration cation exchange capacity because of existence in abundance soil organic matter. Therefore we used various on site in Situ technologies by phase for overcome the limitation factors. Target site is petroleum (diesel) impacted filled land and using technologies are SVE(Soil Vapor Extraction), BV(Bioventing), Bioremediation, Soil flushing, Chemical oxidation.

• Journal of Soil and Groundwater Environment
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• v.17 no.6
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• pp.69-81
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• 2012

Diverse geostatistical tools such as kriging have been used to estimate the volume and spatial coverage of contaminated soil needed for remediation. However, many approaches frequently yield estimation errors, due to inherent geostatistical uncertainties. Such errors may yield over- or under-estimation of the amounts of polluted soils, which cause an over-estimation of remediation cost as well as an incomplete clean-up of a contaminated land. Therefore, it is very important to use a better estimation tool considering uncertainties arising from incomplete field investigation (i.e., contamination survey) and mathematical spatial estimation. In the current work, as better estimation tools we propose stochastic simulation approaches which allow the remediation volume to be assessed more accurately along with uncertainty estimation. To test the efficiency of proposed methods, heavy metals (esp., Pb) contaminated soil of a shooting range area was selected. In addition, we suggest a quantitative method to delineate the confident interval of estimated volume (and spatial extent) of polluted soil based on the spatial aspect of uncertainty. The methods proposed in this work can improve a better decision making on soil remediation.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.351-354
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• 2002

In this study, variation of electrochemical parameters and characteristics of lead immobilization due to phosphoric acid injection in soil were studied during electrokinetic remediation of lead contaminated soil. TCLP result showed about 100% of soil was satisfied TCLP regulation criteria. And injected ion from cathode reservoir by ionmigration was proportionate to concentration of phosphoric acid and elapsed time. Therefore, when removal is infeasible or not cost-effective, in situ immobilization method would be more effective.

• Journal of Soil and Groundwater Environment
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• v.14 no.6
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• pp.95-100
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• 2009

Strategies incorporating more efficient energy use into remediation of contaminated sites, which are those of important elements in green remediation, are developed and discussed in this work. Firstly, from several case studies of remedial actions in Korea, thermal desorption and/or in-situ method including pump-and-treat were found energy intensive and soil washing less intensive. In order to use energy efficiently and minimize use of fossil fuels during land revitalization process, it is necessary to optimize energy intensive systems, to use low energy remediation systems (such as bioremediation), and to integrate renewable energy sources. Furthermore, economic incentive systems such as subsidy need to be adopted if renewable energy sources are incorporated into remediation of contaminated sites.

• Journal of Soil and Groundwater Environment
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• v.25 no.4
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• pp.1-6
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• 2020

Recently, ex-situ remediation technologies has been emerging to clean up contaminated soils mainly because the in-situ techniques have limited applicability and technical difficulties in relatively small contaminated sites. Accordingly, implementation of off-site treatment and disposal have been continuously increased in soil remediation and restoration projects in Korea. However, in many cases, reclaimed soil is still not properly recycled or reused. Therefore, there is an urgent need to document the current status of soil management practices in soil remediation projects in the nation. This study presents a survey of soil contamination status and remedial approaches in Korea based on soil cleanup projects completed in 2015 - 2019, and proposes the possible options of the recycling or reusing the reclaimed soils under compliance with related regulations. The results of the soil survey showed soil contamination was most severe in gas stations, industrial facilities, and military areas. The major types of pollution were related to the petroleum-contaminated site (TPH and BTEX) with 77.0% occurrence in all the contaminated sites. The reclaimed soils were mostly reused as a ground filling-up soils in industrial facilities (60.0%) and warehouses (37.0%).

• Proceedings of the Korean Geotechical Society Conference
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• 1999.03a
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• pp.543-550
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• 1999

Hazardous substances produced from industrial sectors have caused serious contamination of soils and groundwater. The hydrophobic organic compounds in the subsurface are hard to be decomposed, and as they soil on the soil or last as a NAPL they might contaminate the groundwater for a long time. Although we recognize the danger of contaminated subsurface, very little was known about the effective remediation technique. This paper focuses on the remediation of the p-Cresol which contaminated subsurface by applying the surfactant-enhanced description technique. Sorption characteristics of soils and organic compounds are studied, and the applications of surfactant solution are studied for effective rededication. The results from this study could be used as some data for surfactant-enhanced rededication. The flexible-wall permeameter tests are performed in which in-situ remediation is simulated. Results show that triton X-100 at 2% solution disrobes p-Cresol 1.7 times as much as water description in the flexible-wall permeameter tests.