• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.437-440
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• 2005

서울시는 복개천이었던 청계천을 복원하여 도심지를 통과하는 하천을 만들기 위해 청계천 복원 공사를 수행하고 있다. 청계천 복원 공사 구간을 포함하는 유역에는 서울시 지하철 1, 2, 4, 5, 6호선 등이 통과하고 있으며, 도시 내 비수시설, 하수관거시설 등 자연적인 수문현상에 영향을 주는 인위적인 요소들이 복합적으로 존재하고 있다. 때문에 청계천 복원 공사 후 유역내의 여러 요인들과 공사의 정도에 따라 누수가 발생할 것으로 예상된다. 공사 후 청계천에서의 누수율에 대한 측정은 공사의 성공여부를 결정하고, 향후 지속적인 누수가 예상되는 청계천의 유지 보수에 있어서 매우 중요하다. 특히 청계천의 손실량의 대부분을 차지할 지하로의 누수에 대한 측정은 매우 중요하다. 따라서 누수율을 측정하고, 누수율과 주변 요인들과의 관계를 추정할 수 있는 수문모델링을 수행할 필요성이 있다. 수문모델링은 일회성으로 끝나는 것이 아니라 지속적으로 수행될 필요가 있는데, 그러기 위해서는 청계천 유역에서의 지속적인 수문관련 인문 자연자료를 획득하여 정리할 필요성이 있다. 본 연구에서는 청계천 복원 공사 구간의 유역에 대한 인문 자연자료를 GIS(지리정보시스템)을 이용하여 수치도면과 속성테이블 형태로 데이터베이스화한다. 그럼으로써 청계천 주변 유역에 대한 도시형 수문 모델링 연구에 활용하고, 아울러 공사 후 지속적으로 누수율을 측정하는데 자료를 원활히 제공하여 청계천의 유지 보수에 도움을 줄 수 있는 체계를 마련하였다.

• Proceedings of the KSEG Conference
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• 2002.04a
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• pp.235-248
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• 2002

Ground water development skill growth and life circumstances improvement increase ground water use. So managerial difficulties and various problems about ground water occur. Poor ground water management organization, lack of management person, thoughtless development add ground water pollution and lack of water volume. And local excessive developments or abandoned well occur. This paper presents ground water management system model making use of GIS and helps effective management by realizing necessary analysis functions in ground water management system and ground management methods. Local information of ground water recorded and development data, site examination data made D/B. And linearment analysis data making use of a satellite image data, hydraulic test data, the quality of water examination data, these local characteristic values made out thematic maps and making use of these data can form elementary data of ground water modeling It makes easy to understand environmental development conditions and pollution source conditions about new ground water development location, linearment growth, DRASTIC, the quality of water examination. Ground water management system making use of these functions can choose right location of ground water.

• Journal of the Korean Association of Geographic Information Studies
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• v.6 no.2
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• pp.65-79
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• 2003

In this study GIS based pre- and post-processing tool for the Visual MODFLOW that is specific software to model groundwater flow is developed. This tool not only makes input data scientifically but also manages input and output data in terms of the groundwater flow analysis. In addition it can storage project products systematically into Oracle database. The most characteristic figure of this processing tool is to provide the module, which automatically or semi automatically develops various grid cell sizes using GIS ArcView and also produces DXF files reflecting various boundary conditions in the modeling zone. In particular, eminences of this research are to create 3 dimensional hydrogeological structures with 2 dimensional GIS ArcView and to conduct pre- and post- processing along with same topology and data format of the MODFLOW.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.366-369
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• 2004

조석의 효과가 대수층에 미치는 해안대수층에서 지하수-기표수 상호작용에 관한 모사를 위해 수치모델링을 이용하였다 모사에 사용한 모델은 하천경계와 해안경계가 서로 직교하며 하천은 대수층을 부분 관통하고 있다. 해안경계와 하천경계에 의한 동시영향을 함께 모사한 결과, 해안경계에 의한 효과는 일정한 범위까지만 나타났으나, 하천경계에 의한 영향은 시간의 증가에 따라 영향범위가 넓어졌다. 하천경계와 해안경계조건이 만나는 부근에서는 해안경계에 의한 지하수위의 반복적인 상승과 하강으로 인해 두 경계조건에 의한 지하수위가 상호 상승작용을 일으키기도 하고 상호 상쇄되어 지하수위의 변화가 없는 엉역이 나타나기도 한다. 따라서 이러한 하천과 해안경계조건이 상호 교차하는 주변 대수층에서의 수위를 측정하여 해안대수층에서의 수리상수를 추정하면 수리확산계수를 과대 혹은 과소평가하는 오류를 범할 수 있으므로 주의를 요한다.

• Journal of Soil and Groundwater Environment
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• v.13 no.5
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• pp.88-95
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• 2008

In this study, impact of tunnel construction on groundwater level and flow was investigated by simulation modeling, and tried to find optimal assessment method for minimization of geo-environmental problems due to tunnel construction. As a study area, Gyerong mountain area scheduled for tunnel construction was selected and the impact of tunnel construction on geo-environment compared to situation before construction was simulated. Simulation result showed that groundwater level down was observed during tunnel construction and recovered after completion of tunnel construction.

• Magazine of korean Tunnelling and Underground Space Association
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• v.4 no.2
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• pp.22-31
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• 2002

• Journal of Soil and Groundwater Environment
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• v.13 no.4
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• pp.8-21
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• 2008

A series of three-dimensional numerical simulations using a hydrodynamic dispersion numerical model is performed to analyze quantitatively impacts of layered heterogeneity of geologic media and groundwater pumping schemes on groundwater flow and salt transport in coastal aquifer systems. A two-layer heterogeneous coastal aquifer system composed of a lower sand layer (aquifer) and an upper clay layer (aquitard) and a corresponding single-layer homogeneous coastal aquifer system composed of an equivalent lumped material are simulated to evaluate impacts of layered heterogeneity on seawater intrusion. In addition, a continuous groundwater pumping scheme and two different periodical groundwater pumping schemes, which withdraw the same amount of groundwater during the total simulation time, are applied to the above two coastal aquifer systems to evaluate impacts of groundwater pumping schemes on seawater intrusion. The results of the numerical simulations show that the periodical groundwater pumping schemes have more significant adverse influences on groundwater flow and salt transport not only in the lower sand layer but also in the upper clay layer, and groundwater salinization becomes more intensified spatially and temporally as the pumping intensity is higher under the periodical groundwater pumping schemes. These imply that the continuous groundwater pumping scheme may be more suitable to minimize groundwater salinization due to seawater intrusion. The results of the numerical simulations also show that groundwater salinization in the upper clay layer occurs significantly different from that in the lower sand layer under the periodical groundwater pumping schemes. Such differences in groundwater salinization between the two adjacent layers may result from layered heterogeneity of the layered coastal aquifer system.

• The Journal of Engineering Geology
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• v.26 no.4
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• pp.461-471
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• 2016

Numerical modules based on a conventional thermo-hydrological numerical model, TOUGH2, are developed to provide a numerical modeling technique for a standing column well (SCW). Cooling and heating operations for two different types of SCW are then simulated using these modules. Modeling showed these operations to be significantly influenced by heat exchange and fluid mixing between the SCW and the adjacent geologic formation and groundwater. The results also reveal that heat exchange between the oppositely flowing outflow and inflow in the PVC or PE pipe and the SCW borehole is an important factor. Overall, the numerical modeling technique developed here can reasonably simulate fluid flow and heat transport phenomena in the complex internal structures of a SCW. The proposed technique can be used practically for the quantitative analysis of heat exchange in a SCW at the design, construction, and operation stages.

• Journal of the Geological Society of Korea
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• v.54 no.5
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• pp.545-556
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• 2018

This study was conducted to estimate the deep percolation using numerical modeling and field observation data based on rainfall in Haean basin. Soil moisture sensors were installed to monitoring at 30, 60 and 90 cm depths in four sites (YHS1-4) and automatic weather station was installed to around YHS3. Soil moisture and meteorological data was observed from March 25, 2017 to March 25, 2018 and May 06, 2016 to May 06, 2018, respectively. Numerical analysis was performed from June to August, 2017 using the HYDRUS-1D. Average soil moisture contents were high to generally in YHS3 for 0.300 to $0.334m^3/m^3$ and lowest in YHS1 for 0.129 to $0.265m^3/m^3$ during the soil moisture monitoring period. The results of soil moisture flow modeling showed that field observations and modeling values were similar but the peak values were larger in the modeling result. Correlation analysis between observation and modeling data showed that r, $r^2$ and RMSE were 0.88, 0.77, and 0.0096, respectively. This show high correlation and low error rate. The total deep percolation was 744.2 mm during the period of modelling at 500 cm depth. This showed that 61.3% of the precipitation amount (1,214 mm) was recharged in 2017. Deep percolation amount was high in the study area. This study is expected to provide basic data for the estimation of groundwater recharge through unsaturated zone.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.401-404
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• 2003

경북 고령군 다산면의 충적층 강변여과 취수에 따른 수위변화 모델링을 시도하였다. 단순화된 2가지 모델을 기본으로 하여 1일 평균 1만 5천톤의 상수도 공급 시, 일정수두 유지를 위한 연간 취수 계획 및 적정 취수량을 검토하였다. 한편, 질량 균형(mass balance)을 통하여 모델 검증 및 시기별 하천수와 지하수의 유입 비율을 예비적으로 산정하였으며, 투수계수와 함양량 변화에 따른 지하수위의 민감도를 검토하였다. 하천수 유입 비율은 시기별로 65∼85% 범위를 갖는 것으로 나타났으며, 지하수위는 함양량 변화에는 둔감한 반면, 투수계수에 대해서는 상대적으로 민감한 것으로 평가되었다.