• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2002.10a
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• pp.257-260
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• 2002

This study develops a GIS-based system which examines the adequacy of the Groundwater development project before the actual designing of the project. Using the system developed here, we can transfer simulation results obtained by WHPA regarding Groundwater levels in new development projects into GIS. We can also judge whether a Groundwater development project should be permitted through examining overlaps of the effects of the development and comparing with other pollutants. Since a two-tiered system which shares DB using inter- and intranets is developed, all the departments in the ministry of agriculture and forest and the agriculture base corporation can share accurate, reliable and latest information related to Groundwater.

• Spatial Information Research
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• v.9 no.2
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• pp.207-225
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• 2001

This study develops a GIS-based system which examines the adequacy of the Groundwater development project before the actual designing of the project. A system environment is constructed in order to efficiently and scientifically manage and analyze data related to Groundwater through a Server/Client environment. For this programs such as GIS S/W ArcVies3.2, RDBMS ORACLE, ArcSDE (Spatial Database Engine) are used. WHPA and AQTESOLV are employed as a underground water simulation program and Scripts, a language for ArcView, is used to develop graphic user interface (GUI). Using the system developed here, we can transfer simulation results obtained by WHPA regarding Groundwater levels in new development projects into GIS. We can also judge whether a Groundwater development project should be permitted through examining overlaps of th effects of the development and comparing with o pollutants. At the same time, the system has a feature of supporting Groundwater development and based designing through judging the proper amount of Groundwater in a new project. It is also possible to easily and quickly prepare charts and reports using the outputs of the system. Since a two-tiered system which shares DB using inter-and intranets is developed, all the departments in the ministry of agriculture and forest and the agriculture base corporation can share accurate, reliable and latest information related to Groundwater.

• Economic and Environmental Geology
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• v.42 no.2
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• pp.133-141
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• 2009

For economic impact analysis on a R&D project of high-yield groundwater development in Jeju conducted by KIGAM from 2004 to 2007, benefit/cost ratio(BCR), net present value(NPV), and internal rate of return(IRR) were calculated by contingent valuation method(CVM), production function analysis, domestic water market analysis and technology factor analysis. Measurable direct impact parameters among the major outputs of this R&D project consisted the estimation 4 high-yield and high mineral groundwater reserve in Jeju. Annual use of the reserve by piped water and bottled water was estimated as 12.23 million ton and its monetary value was calculated as 293.4 million dollar in 2006 year value applied of 5.5% discount rate. Economic impact of this R&D project in NPV of year 2006, with applying a discount rate of 5.5%, was identified and estimated as 13.66 million dollar in NPV, 4.05 points in BCR, and 22.74% in IRR, respectively. Additional early launch benefit was 5.58 million dollar. Even increased of the 1% discount rate, NPV of this R&D project was also positive as 12.18 million dollar and BCR was 3.71.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.497-501
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• 2005

근래 들어 도시화로 인한 물순환 파괴를 근본적으로 연구하고 이를 정상화하기 위한 체계적이고 통합적인 유역관리 기술이 요구되고 있다. 유역통합관리의 이론을 실제로 적용한 계획을 세우기 위해서는 Heathcote(1998)가 제안한 다음과 같은 단계별 절차를 수행하는 것이 바람직하다. 단계별 절차는 (1) 대상유역에 대한 정보수집, (2) 문제점 도출, (3) 분명한 목적 수립, (4) 대안의 구성, (5) 대안의 검토, (6) 대안의 효과분석, (7) 최종계획 수립으로 이루어져 있으며 본 연구에서는 3단계의 과정에 해당된다. Heathcote(1998)는 대안의 선정과 평가를 위한 방법으로 단순평가방법(simple assessment method)과 세부평가방법(detailed assessment method)으로 구분하였는데 본 연구에서 수행한 내용은 단순평가방법에 해당된다. 본 연구는 안양천 유역에서 물순환 건전화의 핵심을 건천화 방지로 판단하고 이를 위한 대안을 크게 지표수, 지하수, 대체수자원 분야로 구분하여 제시하였다. 지표수 분야의 경우 구조적인 대안으로 소규모 저수지의 개발, 타유역에서의 도수, 보를 이용한 수량 확보, 우오수분리벽을 이용한 상류유출수의 확보, 저협수로 형성, 하천바닥에 차집관로 매설 방지 및 차집관로 유지관리 등이 있으며 비구조적인 대안으로는 기존 저수지의 유지용수 공급을 위한 운영, 유수지의 다목적 활용, 하천수 직접취수 제한 등이 있다. 지하수 분야의 대안으로는 지하철 용출수의 재이용, 지하수의 과다이용 제한, 침투증진시설의 설치 등이 있으며 대체수자원 분야의 대안으로는 하수처리수를 고도처리하여 유지용수로 재이용하는 것, 중소규모 하수처리장의 상류 설치, 대규모 사업장의 폐수를 고도처리하여 활용하는 것, 상수도의 이용 등이 있다. 이러한 여러 가지 대안들은 Walesh(1989)가 제안한 절차에 따라 기술가능성(technical feasibility), 경제성(economical efficiency), 환경성(environmental feasibility) 등을 정성적으로(qualitatively) 파악하여 실현가능한 대안을 선정하였다. 이렇게 선정된 대안들은 중유역별로 검토하여 효과가 있을 것으로 판단되는 대안들을 제시하는 예비타당성(Prefeasibility) 계획을 수립하였다. 이렇게 제시된 계획은 향후 과학적인 분석(세부평가방법)을 통해 대안을 평가하고 구체적인 타당성(feasibility) 계획을 수립하는데 토대가 될 것이다.

• Tunnel and Underground Space
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• v.19 no.3
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• pp.248-260
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• 2009

With regard to oversea mineral resources development, recent trend has been changed from a simple capital investment to a direct development of the resources. In relation to the stability of a slope in large open-pit coal mine, groundwater system was investigated and the validity of horizontal drainage hole was evaluated in Pasir coal mine, Indonesia. In this work, various field tests were carried out for a characterization of groundwater system, which included in-situ permeability measurement, tracer test and monitoring of groundwater levels. Especially, the influence of SM river on the characteristics of the groundwater flow system was mainly inspected. For the permeability measurement, Guelph permeameter was employed, and was found that sandstone was more permeable than mudstone and coal seam. From a comparison of lithological structure and the results of groundwater level monitoring, sandstone and thin coal seam with fractures were found to be a main channel for groundwater flow. In the results of tracer tests, the effect of SM river on the groundwater system depends on the geological structure of its base. To identify the effect of horizontal drainage holes, 2-D groundwater modeling was performed. Four different cases were tested, which are different from the length of drainage hole and the existence of pond on top of the slope. To enhance the drainage effect and slope stability, the drainage hole should be drilled to the depth of coal seam layer, which provides a main pathway of groundwater flow and embedded by sandstone. For this purpose, correct identification of surrounding geology should be preceded.

• The Journal of Engineering Geology
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• v.4 no.3
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• pp.297-309
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• 1994

For a total of 210 city and Kun areas in Korea, a model was developed to predict the amount of groundwater use at each area. At first, the total areas were classified into 3 groups by the characteristics of groundwater use: residential(87), industrial(27) and agricultural (96) areas. Among them, type areas, represented by the dominant groundwater usage for typical purposes, were selected: residential(22), industrial(8) and agricultural(32) areas. Data for the various factors possibly related to the groundwater use were statistically analyzed. The factors include, 1) agricultural area, 2) industrial area, 3) adininistrative unit area(city or Kun), 4) population, 5) groundwater capadty for community water supply, 6) average water supply for a person per day, 7) agricultural water-use, 8) industrial water-use, 9) residential wateruse, 10) rates of community water supply. The data were correlated to the total amount of groundwater use, and the correlations tested at the 95% and 99% significance levels. Influential, significantly related, factors were identified from the tests. Using the multiple regression method with the influential factors, predictive equations were drawn to calculate the amount of groundwater use for residential-industrial and agricultural areas, respectively. The equations were calibrated to minimize the RMS(root mean square) of the differences between predicted and observed groundwater use. After the validation with future data, the model can be utilized in the regional development plans to predict the maximum groundwater demand at each area.

• Journal of Korea Water Resources Association
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• v.41 no.8
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• pp.835-843
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• 2008

In Korea, riverbank filtration has drawn attention since 1990's as an alternative having potential to stably meet the ever-increasing water demand. Some cities located in the Nak-dong River Basin are currently supplying water through riverbank filtration. This research is on the application of riverbank filtration for stable water quality in Seoul. For this purpose, we have evaluated developable amount of water with riverbank filtration for the Han River. This paper focuses on the Kwangnaru site, which was selected through a systematic analysis in the companion paper. We have conducted groundwater modeling for a proposed system of wells and an artificial lake. In the Kwangnaru district, the river length to constitute a well system was identified to be about 1,200m, due to the topography and the field condition such as ecosystem preservation zone. After many design changes, it was found that the maximum developable amount of $23.36\;million\;m^3$/year could be obtained, when 16 pumping wells were built in every 80 meters along with an artificial lake upstream.

• Journal of Soil and Groundwater Environment
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• v.14 no.5
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• pp.18-28
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• 2009

Both feasibility and accuracy of lumped approach to group 12 organic compounds in mixtures into a fewer number of pseudocompounds in sorption processes were evaluated using mixtures containing organic compounds with various physicochemical properties and low-surface-area mineral sorbents. The lumped approach for sorption to simulated mineral sorbents was developed by cluster analysis from statistics. Using the lumped approach, the sorption estimated from both reduced number of pseudocompounds and their sorption parameters (i.e., $K_f$, n) can approximate sorption behavior of complex organic mixtures. Additionally, the pseudocompounds for various mixtures to different types of low-surface-area mineral sorbents can be estimated a priori from the physicochemical properties of organic compound (i.e., ${\gamma_w}^{sat}$). Therefore, the lumped approach may help to simplify the complex fate and transport model of organic contaminant mixtures, reduce experimental efforts, and yet provide results that are statistically identical for practical purposes. Further research is warranted to enhance the accuracy of lumped approach using the multiple regression analysis considering the H-bonding capacity, site concentrations, functional groups for mineral sorbents.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.9 no.3
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• pp.125-131
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• 1997

In order to analyze the feasibility of the drain layer construction method, which is one of the beach protection methods, a hybrid model is constructed by combining the wave model and the seepage flow model. The used wave model is the analytic solution given by Shuto (1972). and the seepage flow model is used by Richards equation which governs the saturated-unsaturated flow in the porous media. It is concluded by the sensitivity analysis of the hybrid model that the most sensitive parameter in the flow field within the beach is the saturated hydraulic conductivity. The developed hybrid model will be efficiently used in the analysis of the parameter when the drain layers are constructed in the beach, if the field datas are obtained more.

• Journal of the Korean Society of Groundwater Environment
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• v.7 no.2
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• pp.89-96
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• 2000

Slug tests are the most widely used field method for quantification of hydraulic conductivity of porous media. Well recovery is affected by well casing, borehole radii, screened length, hydraulic conductivity, and specific storage of porous media. In this study, a new slug tests model was developed through finite element approximation and the validity and usefulness of the model were tested in various ways. Water level fluctuation in a well under slug test and cons-equent groundwater flow in the surrounding porous medium were appropriately coupled through estimation of well-flux using an iteration technique. Numerical accuracy of the model was verified using the Cooper et al. (1967) solution. The model has advantages in simulations for monitored slug tests, partial penetration, and inclusion of storage factor. Volume coverage of slug tests is significantly affected by storage factor. Magnitude and speed of propagation of head changes from a well increases as storage factor becomes low. It will be beneficial to use type curves of monitored head transients in the surrounding porous formation for estimation of specific storage. As the vertical component of groundwater flow is enhanced, the influence of storage factor on well recovery decreases. For a radial-vertical flow around a partially penetrated well, deviations between hydraulic estimates by various methods and data selection of recovery curve are negligible on practical purposes, whereas the deviations are somewhat significant for a radial flow.