• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.76-81
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• 2006

창녕군 증산리 지역은 신규 취수원 확보 일환으로 강변여과 방식 취수 가능성이 한국수자원공사에 의해서 평가되고 있는 지역이다. 강변여과 방식 취수의 타당성 평가를 위해 현장 지질조사, 시추조사, 전기 비저항 탐사 및 고해상도 탄성파 탐사를 수행하였다. 또한 대상 연구지역에서의 개략적 취수 가능량 산정을 위해 모델링 평가가 수행되었으며, 개별 정호에 대한 양수량 산정을 위해 시험 정호를 설치하였다. 현장 시추 조사와 시료에 대한 입도 분석 결과, 연구 지역의 충적층 두께는 35m 전후이며, 주 대수층 구간은 지표하 $25{\sim}35m$인 것으로 추정되었다. 또한 주 대수층 구간의 수리전도도는 $10^{-2}cm/sec$ 이상으로 주로 모래섞인 자갈층으로 구성되어있는 것으로 평가되었다. 또한 전기비저항 조사 결과는 부분적으로 매우 낮은 비저항 분포 지층을 보여주고 있으며, 이는 주로 실트 및 점토로 된 지층이 부분적으로 퇴적되어 있음을 지시하며, 고해상도 탄성파 탐사 결과는 전반적으로 지하수위는 지표하부 5m 전후에 분포하고, 충적층의 하부 경계는 35 내지 45m인 것으로 해석되었다. 지하수 모델링을 통해, 취수 목표량인 180,000톤/일은 주대수층까지의 지하수위 강하 없이 확보 가능할 것으로 평가되었다. 또한 개별 정호의 산출 특성을 평가하기 위해 시험 정호를 설치하여, 실제 2,700톤/일 예비 양수 시험을 수행하였다. 예비 양수 시험 결과, 양수정에서의 수위 강하는 개략 10m, 양수정관측정에서는 약 0.3m의 수위강하만이 관찰되었으며, 양수 영향권이 수 십 m를 넘지 않을 것으로 판단되었다.서의 S97과 JBR의 세포감염 억제율은 3.85%와 3.63%로 나타났다. $textsc{k}$-casein, CU는 로타바이러스 S97과 JBR에 대해 농도 2000UM에서 97%이상의 억제효과를 나타냈으며, sialic acid는 억제효과가 거의 없었다. K-casein, GMP는 송아지뿐만 아니라 유아의 로타바이러스에 의한 설사를 억제할 수 있을 것으로 기대된다.을 향상하기 위해서는 이러한 부위에 대한 미생물 오염을 낮출 수 있는 세심한 현장 품질관리가 필요하다.en and adolescents, analysed by country, age group and gender. The paper discusses the places young consumers can turn to in trying to fulfil their growing consumer needs. It also examines how much money is at their disposal. It then concludes by considering the influence of "financial socialization" on how young people deal with money.nsumption visions based on the various perspectives, consumers are influenced in the apparel buying decision-making. Many subjects reported experiencing positive affect when imagining positive outcomes of produc

• Journal of Korea Water Resources Association
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• v.50 no.11
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• pp.795-802
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• 2017

This study shows the assessment methodology for the water resources of subsurface dams. The study area is SSangcheon subsurface dam. It is at the estuary of SSangcheon watershed forming the unconfined alluvial aquifer. there are several candidate area which are geologically similar to it at East coast. The groundwater level was computed by a 2-D FDM model, where the watershed discharge is the input as the infiltration term. The baseflow computed as the mean value of 3 watershed dischrge model is $0.5m^3/sec$. And considering the inflow near the baseflow as the dry season inflow, The groundwater level according to the change of inflow and pumping rate was computed. Specifically, Using the real pumping rate $28000m^3/day$ which is equal to the supply amount of drinking water to Sokcho city, The inflow which induce the descended groundwater level to the bottom of aquifer or the ascended groundwater level that cause the surface flow was eatimated. The simulation for increased pumping rate and additional well construction to increase the water resources, was executed. And at the extreme dry season, available pumping rate was estimated.

• Journal of Korea Water Resources Association
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• v.39 no.6 s.167
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• pp.511-520
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• 2006

Riverbank filtration is a natural process, using alluvial aquifers to remove contaminants and pathogens in river water for the production of drinking water. In Korea, most of the drinking water is supplied by surface water in-take. However, maintaining the quality of the drinking water becomes more and more difficult due to the increase of contamination. In riverbank filtration, the understanding of contaminant transport is an important task for the production of high quality drinking water and for the maintenance of facilities. In this paper, the transport behavior of hydrophobic organic contaminants is investigated when contaminants coexist with dissolved organic matter (DOM) and bacteria. In the developed model, the aquifer is thought of as a four phase system: two mobile colloidal phases, an aqueous phase, and a stationary solid matrix phase. The model equations are solved numerically for various situations. Results indicate that the presence of colloidal matters can enhance the mobility of contaminant significantly and that partitioning coefficients play an important role in the process.

• Journal of Korea Water Resources Association
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• v.49 no.1
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• pp.61-72
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• 2016

In Korea, the aquifers at the coastal areas are mostly shallow alluvial unconfined aquifers. To simulate the flow and dispersion in unconfined aquifer, a FDM model has been developed to solve the nonlinear Boussinesq equation. Related analysis and verification have been executed. The iteration method is used to solve the nonlinearity, and the model shows 3-D shape because it is a 2-D y model that consider the undulation of water table and bottom. For the verification of the model, the output of flow module is compared to the 1-D analytic solution of Lee (1989) which have the drawdown or uplift boundary condition, and the two results show almost the same value. and the mass balance of dispersion module shows about 10% error. The developed model can be used for the analysis and design of the flow and dispersion in the unconfined aquifers. The model has been applied to the estuary area of Ssangcheon watershed, and the parameters have been deduced as a result : hydraulic conductivity is 90 m/day, and longitudinal dispersivity is 15 m. And the analysis with these parameters shows that the wells are situated in the influence circle of each others except for No. 7 well. Groundwater discharge to sea is $3700m^3/day$. And the chlorine ion ($cl^-$) concentration at the pumping wells increase at least 1000 mg/L if groundwater dam is not exist, so the groundwater dam plays an important role for the prevention of sea water intrusion.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.552-556
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• 2003

창원시 대산면 갈전리의 강변여과수 취수지역의 8개의 시추공의 시추지료로부터 파악된 지하지질과 물리탐사자료를 비교하여 둘 간의 연관성을 검토하였다. 본 연구에서는 이미 얻어진 시추공 자료와 비교ㆍ검토하기 위하여 지구물리탐사를 실시하였다. 수행된 지구물리탐사는 쌍극자배열 전기비저항 수평탐사, 슐럼버져법배열 전기비저항 수직탐사, 지하투과레이다탐사이다. 전기비저항 수평탐사에 의하면 저비저항치의 두께는 낙동강변에 가까울수록 두꺼워지는 경향성을 보이고 있다. 전기비저항 수직탐사 결과는 시추자료와 비교적 잘 일치하고 있으며 지표로부터 세립질 모래층, 중립질 모래층, 세립질 모래층의 구분이 수직탐사 결과에서 잘 나타나고 있다. 또한 GPR탐사와 전기비저항 수직탐사 결과에 의하면, 지하수면은 6m 부근에 위치하고 있음을 알 수 있다.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.6
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• pp.626-633
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• 2006

Bucheon city has been rapidly urbanized and steadily enlarged. Also, the city depends on groundwater as an alternative water resource. The objective of this study is to characterize the hydrogeology in this city including the recharge of groundwater and hydraulic property of an aquifer in order to investigate the chemical characteristics and contamination of groundwater in the Bucheon area. Eleven groundwater wells in the Bucheon area were selected for applying certain hydraulic tests, such as pumping and recovery tests. Theis method and Theis recovery method were used to obtain hydraulic parameters, such as hydraulic conductivity, transmissivity by applying recovery tests. The playground of school and uncovered areas layed a major function of recharging areas. The groundwater well in these areas showed high recharge, transmissivity, and hydraulic conductivity. In a downtown area, groundwaier wells showed low pumping capacity and hydraulic parameters. Groundwater samples were collected from 48 different locations in the Bucheon area and that showed very various chemical composition in groundwater Their electrical conductivity showed various ranges from 70.4 to $1,287{\mu}S/cm$. The composition more significantly affected the groundwater due to the land use and urbanization than that of the aquifer rock type.

• Journal of Korea Water Resources Association
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• v.30 no.1
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• pp.23-34
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• 1997

The Nanji-Do ladnfill is an ill-conditioned reclaimed land without pollution intercepting facilities, and has high ground water table and deep stratum. The purpose of this study is to analyze the solute transport in steady-state groundwater flow and to predict the solute dispersion in Nanji-Do landfill using HST-3D model. As results, the groundwater flows radially outward from the center of No. 1 and No. 2 landfills, and large amount of runoff is moved into Han River. The predicted relative concentration of total dissolved solute(TDS) at two years later was 0.25 in the weathering zone, 0.26 in the lower alluvium, and 0.28 in the upper alluvium. Thus, the further pollution to bottom rock and Han River was predicted by comparing the corresponding present values of 0.29, 0.32 and 0.35.

• Economic and Environmental Geology
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• v.39 no.2 s.177
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• pp.151-162
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• 2006

Characteristics and changes of groundwater qualify were investigated in a riverbank filtration area at Daesan-myeon, Changwon City, Korea. The total dissolved solids (TDS) in groundwater samples collected in October were much less than that in March, indicating the mixing with recharged water from precipitation, as well as the changes of dissolved oxygen profiles at monitoring wells from March to October. Redox processes at depths appeared to trigger Fe and Mn contamination of groundwater in riverbank deposits. Amorphous oxyhydroxides md carbonate minerals such as $MnCO_3$ were probably the reactive phases for dissolved Fe and Mn, respectively. Groundwater contamination by nitrate-nitrogen $(NO_3-N)$ was controlled by the redox processes and subsequent denitrification at the sampled depths. Distribution of $NO_3-N$ concentrations at monitoring wells suggested that the nitrate contaminants were originated from agricultural facilities on the riverbank deposits. Some of monitoring wells, DS-2, D-2, DS-3, SJ-1, and SJ-3, were only partially penetrated into the sand/gravel aquifer, and subsequently, could not fully function to detect the water quality changes for the pumping wells. Proper measures, with regulating agricultural activities in the riverbank deposits, should be carried out to prevent groundwater contamination of the riverbank filtration area.

• Journal of Soil and Groundwater Environment
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• v.12 no.6
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• pp.17-25
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• 2007

Convergent flow tracer test for 2 m (IW-1 well) and 5 m (IW-2 well) of test scale was conducted at the alluvial aquifer with high permeability and storativity. Pumping rate for convergent flow tracer test were $2,500m^3/day$, and the chloride tracer of 5 kg was instantaneously injected into IW-1 and IW-2 wells. Differences of first arrival time and peak concentration were analyzed by using the concentration breakthrough curves of chloride. Recovered chloride mass were analyzed by recovered cumulative mass curves. And, increment and decrement for chloride concentration were analyzed through chloride concentration versus recovered cumulative mass ratio graphs. Also, increment and decrement ratios of chloride concentration were estimated through linear regression analyses for increment and decrement intervals of chloride concentration. Longitudinal dispersivities were estimated by quot;Converging Radial Flow With Instantaneous Injectionquot; method using CATTI code. Longitudinal dispersivities estimated by CATTI code were 0.4152 m between pumping well and IW-1 well, and 3.2665 m between pumping well and IW-2 well. Longitudinal dispersivity was increased according to far distance from the pumping well. The longitudinal dispersivity according to distance were estimated as 0.21 between pumping well and IW-1 well, and 0.65 between pumping well and IW-2 well.

• Journal of Soil and Groundwater Environment
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• v.11 no.2
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• pp.45-55
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• 2006

A 2-D unconfined flow model is developed to analyze annual variations of groundwater level and bank filtration rate (BFR) for an experimental riverbank filtration site in Koryeong, Korea. Two types of boundary conditions are examined for the river boundary in the conceptual model: the static head condition that uses the average water level of the river and the dynamic cyclic condition that incorporates annual fluctuation of water level. Simulations show that the estimated BFR ranges $74.3{\sim}87.0%$ annually with the mean of 82.4% for the static head boundary condition and $52.7{\sim}98.1%$ with the mean of 78.5% for the dynamic cyclic condition. The results illustrate that the dynamic cyclic condition should be used for accurate evaluation of BFR. Simulations also show that increase of the distance between the river and the pumping wells slightly decreases BFR up to 4%, and thereby indicate that it is not a critical factor to be accounted for in designing BFR of the bank filtration system. A sensitivity analysis is performed to examine the effects of model parameters such as hydraulic conductivity and specific yield of the aquifer, recharge rate, and pumping rate. The results demonstrate that the average groundwater level and BFR are most sensitive to both the pumping rate and the recharge rate, while the water level of the pumping wells is sensitive to the hydraulic conductivity and the pumping rate.