• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.09a
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• pp.199-203
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• 2001

온양온천지구의 13개 온천공에서 채취한 온천수의 수질 자료를 이용하여 심부 온천수와 천부 지하수의 혼합비를 추정하였다. 온천수의 pH, EC, 및 주요 이온의 농도는 40~54$^{\circ}C$의 범위를 나타내는 온천수의 온도와 뚜렷한 선형의 비례관계를 나타내며, 수온이 낮아질수록 천부 지하수의 수질 특성에 가까워지는 특성을 보인다. pH, $K^{+}$, F$^{-}$, 및 Si는 온도와 정(+)의 비례관계를, $Ca^{2+}$, $Mg^{2+}$, Cl$^{-}$, HCO$_3$$^{-}$, SO$_4$$^{2-}$ , NO$_3$$^{-}$ 및 EC는 부(-)의 비례관계를 나타낸다. 온천수의 온도와 수질과의 이러한 상관성은 수질 특성이 상이한 고온의 심부 온천수와 저온의 천부 지하수가 각 온천공에서 서로 다른 비율로 혼합되어 나타난 결과로 해석된다. 최고 온도를 나타내는 온천수와 온천지구 내 지하수의 수질을 끝 성분(end member)으로 가정하고 혼합비를 계산한 결과, 온천지구에서 현재 채수되는 온천수에는 20% 내외의 천부 지하수가 혼합되고 있는 것으로 나타났다. 온천수와 지하수의 수질 자료를 파이퍼 다이어그램에 도시한 결과 $Na^{+}$-HCO$_3$$^{-}$의 유형을 나타내는 13개 온천수는 전체적으로 직선 상에 분포하는 경향을 보였으며, $Ca^{2+}$-HCO$_3$$^{-}$의 유형을 나타내는 지하수는 직선의 연장선상에 분포하여 온천수와 지하수의 혼합이 일어나고 있음을 보여준다. 온천공 수질 검층 결과, 심도 145m를 경계로 지하수와 온천수가 상하부에 부존되어 있으며, 경계부에서 혼합이 발생하고 있는 것으로 추정된다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1998.11a
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• pp.114-118
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• 1998

농촌지역인 공주시 유구읍 명곡리 지역의 천부지하수와 먹는 샘물 공장의 취수정 심부 지하수을 대상으로 지화학적 특성을 밝히고, 물-암석 상호반응과 오염물질 유입에 대해서 토의하였다. 천부 지하수의 화학적 유형은 Ca-HCO$_3$형에서 Ca-Cl(SO$_4$)형으로 전반적으로 약산성화 되어있고, $K^{＋}$, Cl$^{-}$, NO$_3$$^{-}$오염이 상당히 진행되어 70 %이상이 음용수로 불가능한 상태이다. 군집방법에 의하면 신선한 물과 오염된 물사이에 뚜렷한 경향의 차이를 보인다. 천부지하수의 주요 오염원은 각가정에 있는 재래식 화장식, 생활하수, 가축의 축사, 비료등으로 보인다. 심부지하수는 알카리성의 Na-HCO$_3$형에서 Na(Ca)-HCO$_3$형의 화학적 유형이며, 2 TU 이하의 삼중수소 함량으로 1950년대 이전에 함양된 비교적 오랜 물-암석 상호반을 거친 물로 판단된다. 반면 천부형 지하수는 1950년대 이후에 충전된 상당히 젊은 연령의 지하수로 보인다. $^{18}$ O/$^{16}$ O, D/H 환경동위원소 조성값으로 볼 때 심부지하수의 함양지역은 고도의 효과를 보인다. 이 연구결과는 농촌지역의 지하수 수질 오염에 대한 하나의 사례연구로 향후 전국을 대상으로 한 농어촌지역의 지하수 오염연구에 기본방향을 제시하는데 의의 가 있을 것이다.

• The Journal of Engineering Geology
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• v.15 no.4 s.42
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• pp.391-405
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• 2005

Chemical and isotopic analysis for stream water, shallow groundwater, intermediate groundwater and deep groundwater was carried out to grasp hydrogeochemical characteristics of groundwater in the Heunghae area, Pohang city. Water type of stream water and shallow groundwaters is typified as Ca-Cl type, intermediate groundwater is $Na-HCO_3$, and deep groundwater is prominent in Wa-Cl type. $HCO_3^-\;and\;SiO_2$ in shallow groundwater are originated from weathering of silicate minerals, whereas those of deep groundwaters are resulted from weathering of carbonate minerals. Ca and Mg ions in both shallow and deep groundwaters are resulted from weathering of calcite and dolomite. $SO_4^{2-}$ in shallow groundwater is originated mainly from pyrite oxidation. As well depth increases, pH and TDS increase, but Eh and DO decrease. Alkali metal contents(K, Na, Li) increases as well depth increases, but alkali earth metal(Mg, Ca) and hi concentrations increase as well depth decreases. Anions, halogen elements(F, Cl, Br), and $HCO_3$ contents increase as well depth increases. The average stable isotope value of the groundwater of each depth is as follows; deep groundwater: ${\delta}^{18}O=-10.1\%o,\;{\delta}D=-65.8\%_{\circ}$, intermediate groundwater: ${\delta}^{18}O=-8.9\%_{\circ},\;{\delta}D=-59.6\%_{\circ}$, shallow groungwater : ${\delta}^{18}O=-8.0\%_{\circ},\;{\delta}D=-53.6\%_{\circ}$, surface water : ${\delta}^{18}O=-7.9\%_{\circ},\;{\delta}D=-53.3\%_{\circ}$ respectively.

• Journal of Soil and Groundwater Environment
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• v.8 no.1
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• pp.57-67
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• 2003

Nitrate contamination by human activities is a serious problem to water-supply in agricultural area. Shallow groundwater is the main source of water-supply, but it is very sensitive to contamination. Study area for nitrate contamination is a region of Iljuk, Kyunggi where is an agricultural area having many livestock facilities in various scales. As a result, the points having availability of incoming of external contaminant are 77%, and the ones over the Drinking Water Limit (DWL) are 32～42%. For a nitrogen isotope analysis, all the points having availability of incoming of external contaminant have $\delta$$^{15}$ N-NO$_3$ values over 5$\textperthousand$, and the points of 59% are strongly affected by nitrogen originated from animal wastes. The major source of nitrate in this area is intensive livestock facilities. Even though a livestock facility had enclosed, it affects groundwater quality for a long time. The chemical property of contaminant source is various according to animal species in surface water, but not in groundwater since some solutes are removed by reactions during an inflow to subsurface.

• Journal of the Korean Society of Groundwater Environment
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• v.6 no.2
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• pp.53-58
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• 1999

This study was carried out evaluate to identify water quality and contamination characteristics of the shallow groundwater. and their seasonal variation in the rual area of the Yongin city. Groundwater sample were collected two times (in April and September) from a total of 19 well for domestic water supply. and surface-water samples from six locations. For cations, Ca and Mg predominated. In anion competition. the influence of Cl was obvious in the april samples. However. HCO$_3$ was a major component in the september samples. Electric conductivities and the concentrations of NO$_3$-N in groundwater samples significantly decreased from the april samples to the september samples This indicates a significant seasonal variation in the shallow groundwater composition. When the shallow aquifer is connected to the surface water. then metals sorbed on the stream sediments could occur at nearby wells through the induced recharge. Contaminants at ground surface appeared to be transported to the groundwater system infiltration during the spring melt.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.4
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• pp.383-391
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• 2020

In this study, Hunt's analytical solution and Ward & Lough's analytical solution for two-layered leaky aquifer system were used to estimate stream depletions due to shallow and deep groundwater pumping, and their differences were compared. Depending on the combination of the separation distance between the stream and the well, the transmissivity and the storage coefficient of the aquifer, and the leakage coefficient between the upper and lower layers, the stream depletion, which is the amount of stream water reduction compared to the amount of groundwater pumping, for each of 45,000 cases was calculated for both shallow and deep groundwater pumping, and the differences were analyzed quantitatively. When the leakage coefficient was very small, with a value of 10^-61/d, the difference in the average five-year stream depletion due to the pumping of shallow and deep groundwater showed a large deviation of up to 0.9 depending on the given hydraulic characteristics; this value exponentially decreased as the stream depletion factor (SDF) increased. This exponential relationship gradually weakened as the leakage coefficient increased due to interaction effects between layers, resulting in a small difference of up to 0.2 when the leakage coefficient reached 10^-31/d. Under the condition of greater interlayer hydraulic connectivity, there was little influence of the depth of groundwater pumping on the stream water reduction.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.05a
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• pp.98-98
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• 2000

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.05a
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• pp.56-67
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• 2003

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.144-147
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• 2002

효과적인 국내 충적층 지하수의 이용을 위해서는, 충적 대수층의 내부 구조를 정밀하게 평가하여야 한다. 특히, 강변여과, 인공 침투지 등의 적극적인 충적 대수층의 활용을 위해서는 충적 대수층의 퇴적 환경에 대한 이해가 요구된다. 국내 충적층의 대부분은 하천 둔치 주변에서 하도의 수평 이동에 의해 형성된 경사 지층으로, 니질 박층이 협재하므로 내부의 분균일성에 의해 인접한 취수 공간에도 지하수체의 이동 특성 및 화학적 특성이 달라질 수 있다. 본 연구는 이러한 불균질성을 박히기 위해 지하투과레이다(GPR)를 이용하여 부여 군수리 지역의 천부 충적층에 대한 퇴적학적 분석을 시도하였다. 군수리 지역은 크게 상하 두 개의 충적층으로 구분되며, 상부 수평층은 범람에 의해 형성된 것으로 수직 불균질성이 크고 수평 불균질성은 낮다. 하부 경사층은 수평, 수직 불균질성이 모두 크다. 특히 하부 경사층내에 발달한 하도곡은 인접한 충적층과 분리되어 이 층내의 지하수체 이동은 제한적일 것이고 수질 특성 또한 크게 다를 것으로 판단된다. 본 연구는 충적 대수층에 대한 물리 화학적 특성의 정확한 해석을 위해서 퇴적학적 해석이 선행되어야 함을 시사한다.

• The Journal of Engineering Geology
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• v.14 no.4 s.41
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• pp.469-485
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• 2004

The purpose of this study is to investigate the hydrochemical characteristics of groundwater in the Umsung area, and to elucidate the effect of host rock type, well depth and mineralization zone on the groundwater chemistry. The geology of the study area consists of Jurassic granite and Cretaceous sedimentary rocks, which are bounded by a fault. Most of shallow groundwaters exploited in the Jurassic granite area are used for agricultural purpose, whereas the deep groundwaters in the Cretaceous sedimentary rocks are used for a drinking water. The shallow groundwater shows weak acidic pH, the electrical conductivity ranging from $142\;to\;903\;{\mu}S/cm$, and the chemical type of $Ca-HCO_3\;to\;Ca-Cl(SO_4,\;NO_3)$. A few of shallow groundwaters are contaminated by nitrate, and show high concentration of Fe, Mn and Zn, that reflects the effect of a mineralization zone. The deep groundwater shows neutral to weak alkaline pH, higher electrical conductivity than that of shallow groundwater, and the chemical type of $Ca-HCO_3$. The seepage water from the abandoned mines does not have the characteristics such as acidic pH, high concentration of heavy metals and high sulfate content. The hydrogen and oxygen isotopes of groundwater indicates an altitude effect of the recharge area between deep groundwater and shallow groundwater. In conclusion, the chemical composition of groundwater complicately reflects the effects of their host rocks, well depth, agricultural activity and mineralization zone in the study area.