• 대한지하수환경학회지
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• 제6권4호
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• pp.188-193
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• 1999

지하 대수층에서의 오염물질 이동현상은 지하수 유동에 좌우되며 이를 지배하는 수리지질 파라미터의 결정과 그에 따른 지하수 모델링은 지하수 복원사업에 중요한 역할을 한다. 본 연구의 목적은 실험실 규모의 자유면 대수층에서 획득된 투수계수와 비산출량을 이용하여 다양한 경계조건하에서 지하수 흐름에 대한 민감도 분석을 수행하므로써, 최적의 수리상수를 결정하고 지하수 유동 특성을 파악하는데 있다. 연구결과 모사된 수위저하는 경제조건과 무관하게 관측된 수위저하보다 적게 나타났으며. 투수계수가 비산출율보다 지하수 흐름에 큰 영향을 미치는 것으로 나타났다. 또한 물수지 분석결과 양수시험시 관측정에서 측정된 수위저하는 평형수위나 모사 수위저하보다 크게 나타났으며, 이는 대수층과 우물에서의 수위가 상이함을 지시한다. 이러한 수위의 상이성은 시간영역 광전자파 분석기에 의한 지하수면과 모세관대에서의 수분함량을 관측함으로써 규명되었으며 이는 지하수면 하강시 중력배수의 지연성에 기인하는 것으로 나타났다.

• 자원환경지질
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• 제54권2호
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• pp.247-257
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• 2021

The study area has been contaminated with explosive materials and heavy metals for several decades. For the design of the pump and treat remediation method, groundwater flow before and during groundwater pumping in a contaminated aquifer system was simulated, calibrated, and predicted using a generalized multidimensional hydrological numerical model. A three-dimensional geologic formation model representing the geology, hydrogeology, and topography of the aquifer system was established. A steady-state numerical simulation with model calibration was performed to obtain initial steady-state spatial distributions of groundwater flow and groundwater table in the aquifer system before groundwater pumping, and its results were illustrated and analyzed. A series of transient-state numerical simulations were then performed during groundwater pumping with the four different pumping rates at a potential location of the pumping well. Its results are illustrated and analyzed to provide primary reference data for the pump and treat remediation method. The results of both steady-state and transient-state numerical simulations show that the spatial distribution and properties of the geologic media and the topography have significant effects on the groundwater flow and thus depression zone.

• 대한지하수환경학회지
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• 제7권3호
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• pp.133-140
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• 2000

초정지역은 세계 3대 광천수 생산지의 하나로서 지하수 이용업체들이 집중적으로 지하수 개발을 하고 있어 지하수자원의 고갈이 우려되고 있다. 본 연구에서는 초정지역의 지속적인 개발로 인해 장래 예측되는 지하수 장애에 대처하기 위해 수치모형을 이용하여 초정지역의 지하수 유통해석을 수행하였다. 해석 결과 동북쪽에 위치한 산간유역의 수위의 변화에 비하여, 하류 구릉지역에서는 양수정들을 중심으로 수위 강하가 급격하게 일어나고 있다. 이는 하류 구릉지역에 공장들이 밀집하여 있고 생활용수와 농업용수 또한 많은 양을 양수를 하는데 기인한다. 따라서 향후 지하수자원의 고갈이 우려되며, 이에 대한 대책이 심각하게 요구된다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제17권2호
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• pp.28-36
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• 2012

This study carried out several kinds of investigations such as geology, hydrogeology, groundwater level and quality, surface-water quality, and the quantity and quality of groundwater discharge from the subway to identify the causes of groundwater contamination around the subway tunnel at Suyeong District in Busan City. Geostatistical analyses were also conducted to understand the characteristics of groundwater level and quality distributions. There are Kwanganri Beach and Suyeong River in the study area, which are basically influenced by seawater. The total quantities of groundwater utilization and groundwater discharge from the subway tunnel in Suyeong District are 2,282,000 $m^3$/year, which is 2.4 times larger than the sustainable development yield of groundwater. The lowest groundwater level around the subway tunnel is about 32 m below the mean sea-level. The large drawdown of groundwater led to the inflow of seawater and salinized river water toward the subway tunnel, and therefore the quality of groundwater didn't satisfy the criteria of potable, domestic, agricultural and industrial uses. Distribution maps of groundwater level and qualities produced by kriging were very useful for determining the causes of groundwater contamination in the study area. The distribution maps of electrical conductivity, chloride and sulfate showed the extent of seawater intrusion and the forceful infiltration of the salinized Suyeong River. This study revealed that seawater and salinized river water infiltrated into the inland groundwater and contaminated the groundwater around the subway tunnel, because the groundwater level was seriously drawdowned by groundwater discharge from the subway tunnel. The countermeasure for the minimization of groundwater discharge from the subway tunnel is necessary to prevent the groundwater obstacles such as groundwater depletion, groundwater-quality deterioration, and land subsidence.

• 한국지하수토양환경학회지:지하수토양환경
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• 제15권6호
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• pp.46-52
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• 2010

Derivative analysis, based on the derivative of the drawdown as a function of time (i.e., rate of drawdown change), was applied to the evaluation of hydraulic parameters of the aquifer as an aid of the aquifer test interpretation based on the Theis solutions. Pumping tests were conducted at a coastal fractured aquifer in Muan county, Korea, of which the drawdown data, measured at the two observation wells, were used for derivative analysis. Wellbore storage and transition period were hard to identify at conventional log-log and semi long plots, but was easily recognized by distinctive curves of positive unit slope, hump and negative unit slope in the derivative plot. For the observation well of OW-2 at which wellbore storage and transition lasted over an hour, conventional aquifer analysis would suffer from the uniqueness problems and in further result in erroneous hydraulic parameters. Derivative analysis was found to be effective for distinguishing the drawdown data directly reflecting the aquifer property from those reflecting non aquifer effects such as wellbore storage and transition, which offers a unified methodology to yield correct hydraulic parameters from aquifer test data.

• 한국철도학회논문집
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• 제20권2호
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• pp.248-256
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• 2017

고속철도 콘크리트궤도의 일부 토공구간 침하 원인으로 지하수위 저하가 보고되었다. 이에 본 연구에서는 현장 계측 값과 수치해석을 통하여 지하수위 저하에 따른 침하 영향을 분석하였다. 시행착오법을 이용한 역해석을 통해 구성된 수치해석 모델을 이용하여 지하수위 저하, 연약층의 두께, 성토고에 따른 잔류침하거동을 검토하였다. 4m이상의 연약층이 존재할 경우, 지하수위 저하에 의한 원지반침하량은 30mm이상으로 예상되어 설계 및 시공단계에서 지하수위 거동에 의한 침하도 설계시 고려되어야 할 것으로 보인다.

• 자원환경지질
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• 제28권2호
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• pp.165-176
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• 1995

Dongrae is one of the most famous hot spring resort area in the Republic of Korea. The water temperature ranges $50^{\circ}C{\sim}66$. The chemical composition of the thermal water is quite different from normal groundwater. $Na^+$ and $Cl^-$ are the main components, measured more than 75%, $Ca^{+{+}}$ is contained about 22% and the other ions such as $SO_4$ or $HCO_3$ are the minor components. The heat source is uprising along the fracture zone of granite which is indicated as a subsurface high temperature belt. During the research period of 1991~1992, the groundwater table was lowered down to the depth of about 100 m according to continuous increase of daily use of thermal water. The groundwater table was fluctuated with an amplitude of day, weak or seasion. The groundwater table was the lowest at 18:00 h in a day and also lowest at the weekend for the week period. There was a relavent relationship between drawdown and the amount of thermal water use on a long term base. To protect such a rapid drawdown of groundwater table, Dongrae resort area is now asked to take strong municipal control for the daily use of thermal water.

• 한국환경과학회지
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• 제26권10호
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• pp.1135-1146
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• 2017

At riverbank filtration sites, groundwater levels of alluvial aquifers near rivers are sensitive to variation in river discharge and pumping quantities. In this study, the groundwater level fluctuation, pumping quantity, and streamflow rate at the site of a riverbank filtration plant, which produces drinking water, in the lower Nakdong River basin, South Korea were interrelated. The relationship between drawdown ratio and river discharge was very strong with a correlation coefficient of 0.96, showing a greater drawdown ratio in the wet season than in the dry season. Autocorrelation and cross-correlation were carried out to characterize groundwater level fluctuation. Autoregressive model analysis of groundwater water level fluctuation led to efficient estimation and prediction of pumping for riverbank filtration in relation to river discharge rates, using simple inputs of river discharge and pumping data, without the need for numerical models that require data regarding several aquifer properties and hydrologic parameters.

• 터널과지하공간
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• 제4권1호
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• pp.24-30
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• 1994

Although a dry-system tunnel is not good for reasons fo economy and construction, it has been applied to some tunnels under construction owing to the advantages of good long-term maintenance of tunnel, prevention of consolidation settlement due to the drawdown of groundwater, preservation of the ecosystem, cutailment of operation cost, and so on. The stability of groundwater and the change of the applied water pressure after water proofing were analysed by the finite element method. Using this result, an example of designing the secondary lining for the dry-system tunnel which is to be constructed in low-permeability hard rock was presented.

• 지질공학
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• 제24권2호
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• pp.217-225
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• 2014

대규모 수막재배 시설은 동절기 수막재배 기간 동안 군집 취수정의 영향으로 지하수위가 하강하고 이로 인해 지하수 취수량 확보에 어려움을 겪고 있다. 본 연구에서는 동절기 수막재배지역에서의 집중취수에 따른 정밀한 지하수위 변화 분석을 수행하고자 한다. 대상지역인 청원군의 수막재배지역을 포함한 소유역의 지하수 유동을 모의하기 위해 3차원 유한차분모형인 MODFLOW를 구축하였으며, 중요한 입력자료인 지하수 함양량 시계열 자료는 유역수문모형 SWAT모형을 이용하여 구하였다. 여기에 수막재배지의 일최저기온과 취수가동시간과의 관계를 통해 지하수 이용량을 추정한 선행 연구(Moon et al., 2012)를 참고하여 취수계획을 수립, 지하수 모델링에 반영하였다. 부정류 모델링의 적합도를 평가하기 위해 동절기의 모의된 지하수위 강하 패턴을 관측지하수위 자료와 비교하였다. 모델링 기간은 수막재배가 본격적으로 이루어지는 2012년 11월부터 2013년 3월까지의 107일간으로 정하였다. 모의결과 동절기 지하수위 관측값과 비교적 유사한 지하수 하강을 재현할 수 있었고, 일최저기온을 이용한 취수계획방식이 다른 수막재배지역의 지하수 유동해석에도 적용가능할 것으로 판단되었다.