• 한국지반환경공학회 논문집
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• 제15권4호
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• pp.13-27
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• 2014

Catchments soil erosion, one of the most serious problems in the mountainous environment of the world, consists of a complex phenomenon involving the detachment of individual soil particles from the soil mass and their transport, storage and overland flow of rainfall, and infiltration. Sediment size distribution during erosion processes appear to depend on many factors such as rainfall characteristics, vegetation cover, hydraulic flow, soil properties and slope. This study involved laboratory flume experiments carried out under simulated rainfall in a 3.0 m long ${\times}$ 0.8 m wide ${\times}$ 0.7 m deep flume, set at $17^{\circ}$ slope. Five experimental cases, consisting of twelve experiments using three different sediments with two different rainfall conditions, are reported. The experiments consisted of detailed observations of particle size distribution of the out-flow sediment. Sediment water mixture out-flow hydrograph and sediment mass out-flow rate over time, moisture profiles at different points within the soil domain, and seepage outflow were also reported. Moisture profiles, seepage outflow, and movement of overland flow were clearly found to be controlled by water retention function and hydraulic function of the soil. The difference of grain size distribution of original soil bed and the out-flow sediment was found to be insignificant in the cases of uniform sediment used experiments. However, in the cases of non-uniform sediment used experiments the outflow sediment was found to be coarser than the original soil domain. The results indicated that the sediment transport mechanism is the combination of particle segregation, suspension/saltation and rolling along the travel distance.

• 대한환경공학회지
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• 제30권2호
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• pp.190-198
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• 2008

본 연구에서는 주유소 등의 지하 유류저장탱크나 파이프의 제한된 수명으로 인해 발생할 수 있는 가솔린의 누출에 의해 MTBE로 토양이 오염되었을 경우를 가정하여, 칼럼실험을 수행하고, CXTFIT 기법을 이용하여 토양 내 MTBE의 이동특성을 살펴 보았다. 칼럼실험에서는 토성, 수분함량, 유기물함량, 주입유속을 달리하여, 주입액과 유출액의 MTBE의 농도 측정값을 비교하고, CXTFIT기법을 이용하여 two-site 비평형 흡착모델에 사용된 매개변수(D, R, $\beta$, $\omega$)를 구하였다. 이들 매개변수와 파과곡선을 이용하여 MTBE의 토양 내 이동특성을 살펴보았다. 토양 내 미세입자와 유기물함량이 많을수록 이류에 의한 영향이 감소하는 것으로 나타났으며, 수분함량과 유속의 증가는 이류에 의한 MTBE의 이동을 더욱 가속시키는 것으로 나타났다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제24권3호
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• pp.1-12
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• 2019

Plastics have become essential materials in human life for several decades. Meanwhile, the inadvertent spread of plastic debris from the use of many plastic products has raised global environmental concerns. The risk of microplastics in subsurface environment has received little attention because soil is considered to confine microplastics within the matrix. However, the concentration of microplastics in soil unavoidably increased as a result of an increase in plastic production and use. Based on lab experiments, several researches claimed that microplastics possibly penentrate soil layers. Recently, a few researches reported the occurrence of microplastics in groundwater. This study reviewed the recent reports of microplastic occurrences in soil and groundwater, and the modeling studies for simulating transport of microplastics. Additionally, the difficulties and limits in microplastics researches in soil and groundwater are discussed. Finally, several perspectives on microplastic studies in subsurface environment are suggested.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2001년도 총회 및 춘계학술발표회
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• pp.140-143
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• 2001

The packed column experiments were conducted with commercial Jumunjin sand(SOM content : 0.01 %) and a field soil(SOM content : 0.08 %) in order to understand the effects of water content and soil organic matter(SOM) on the transport of gaseous ozone in unsaturated soil contaminated with phenanthrene. Water content and SOM content were artificially controlled. As water content increased, earlier breakthrough was observed in the beginning of BTC of ozone, because direct contact of gaseous ozone with SOM and phenanthrene was prevented by water film formed between soil particles and gaseous ozone. The total removal of phenanthrene in Jumunjin sand was not affected by water content which was more than 99% at different water content(4.4, 8, 17.3%). However, the removal in field soil at water content 6.5 % and 20 % was 98% and 80 %.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 INTERNATIONAL SYMPOSIUM ON SOIL & GROUNDWATER ENVIRONMENT
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• pp.62-63
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• 2005

• 한국지하수토양환경학회지:지하수토양환경
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• 제10권6호
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• pp.63-67
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• 2005

불포화 토양내에서 가스상 오존의 이동특성에 대한 토양수분과 Light non-aqueous phase liquid (LNAPL)의 영향을 알아보기 토양칼럼실험을 실시하였다 토양수분은 토양입자에 수막을 형성하여 가스상 오존과 토양입자의 직접적인 접촉을 방해하여 오존의 이동을 증가시키는 역할을 하였다. 토양수분이 증가할수록 불포화 토양내의 기-액 접촉면적 감소와 오존의 평균선형유속증가로 인해 오존의 이동속도가 증가하였다. LNAPL로 사용된 디젤유의 경우도 토양 표면에 막(Film)을 형성하여 가스상 오존의 이동을 증가시키는 역할을 하였다. 하지만, 토양 수분과는 반대로 디젤유 농도가 증가할수록 오존의 이동속도는 감소하였다. 토양수분과 LNAPL성분이 동시에 존재할 경우에는 토양입자에 Non-wetting유체로 작용하는 LNAPL에 의해 오존의 이동이 영향을 받는다는 것을 알 수 있었다

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 1999년도 정기총회 및 춘계 공동 학술발표회
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• pp.3-3
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• 1999

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.430-433
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• 2003

Nitrogen pollution in urban and rural groundwater is a common problem and poses a major threat to drinking water supplies based on groundwater. In this work, the kinetics of nitrification-denitrification coupled reactions are modeled and new reaction modules for the RT3D code describing the fate and transport of nitrogen species, dissolved oxygen, dissolved organic carbon, and biomass are developed and tested. The proposed nitrogen transformations and transport model showed very good match with the results of other public codes.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.314-317
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• 2003

Plants may enhance the remediation of munitions at contaminated soils using various natural processes. A computer model can be used as a valuable tool for assisting phytoremediation by predicting the transport and fate of target contaminants at remediation sites. For this research, modeling of phytoremediation and bioremediation of soil contaminated with 2, 4, 6-trinitrotoluene (TNT) was studied. Indian mallow (Abutilion avicennae) was grown in columns packed with 126mg TNT/kg contaminated soils for 50 days and a simulation model was developed to simulate the transport and fate of TNT and its breakdown products interacting with plant roots in a partially saturated soil. The column test showed the substantially enhanced reduction of TNT and greater soil microbial activity in Indian mallow planted soil compared to unplanted soil. The model successfully simulated the fate of TNT and by-products in phytoremediation. The results suggested that plants could provide favorable environments for reduction of TNT.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 1996년도 경북지부 결성 및 추계학술발표회 논문집
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• pp.50-53
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• 1996

This paper reports the experimental results for the determination of the overall partition coefficient of VOCs in unsaturated soil, A chromatographic method was used for the determination of gaseous partition coefficients to natural soil under various water content conditions. The equilibrium vapor pressure of water over saturated salt solution was used to fix the relative humidity of the air and control the water content of the soil systems. The transport behavior was studied for dichloromethane, trichloroethane and dichlorobenzene pollutants, with log octanol-water partition coefficients(log $K_{ow}$ ) which range from 1.25 to 3.39, or water to soil partitioning which varies by 135 times; water solubility constants which vary by 3 times; and vapor pressures which range from 1 to 362 torr. Water content of the soil had a pronounced effect on the effective partition coefficient(between gas and soil + water stationary phase) as well as on the effective dispersion coefficient.