• 미생물학회지
• /
• 제38권4호
• /
• pp.293-298
• /
• 2002

다양한 농도의 영양배지(nutrient broth, NB; diluted nutrient broth, DNB)를 이용하여 음용 지하수중의 세균수를 계수한 결과, 통상농도의 NB배지에 비해 저영양배지인 DNB배지에서 2～50배 이상 높은 계수치를 나타내었다. 이와 같은 결과로부터 지하수중에는 NB배지에서는 중식이 현저히 저해되고 DNB배지에서만 중식이 가능한 저영양세균(oligotrophic bacteria)이 다수 분포하고 있음이라 판단되어 DNB배지로부터 184균주의 저영양세균을 분리하였다. 본 연구에서는 시판 음용수(CW, CJ )와 광천수(DPG, CJG1)에서 분리된 저영양세균 102 균주의 165 rDNA 염기서열을 결정하여 계통분류학적 특성을 검토한 결과 세 개의 주요한 계통군: Proteobacteria $\alpha$-subdivision (49 균주), $\beta$-subdivision (50 균주), $\gamma$-subdivision (3 균주)으로 분류되었다. Proteobacteria $\alpha$-subdivision에는 Afipia, Blastobacter, Bradyrhizobium, Caulobacter, Phenylobacterium, Rhizobioum, Sphingomonas가 포함되었으며, $\beta$-subdivision에는 Acidovorax, Azonexus, Ferribacterium, Janthinobacterium, Leptothrix, Polaromonas, Variovorax가 포함되었고, $\gamma$-subdivision에는 Rhodanobacter 등 다양한 계통군이 확인되었다.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 2000년도 추계학술대회
• /
• pp.87-90
• /
• 2000

The hydrogeochemical and isotopic studies on deep groundwater in the Munkyeong area, Kyeongbuk province were carried out. $CO_2$-rich groundwater (Ca-HC $O_3$ type) is characterized by low pH (5.8~6.5) and high TDS (up to 2,682 mg/L), while alkali groundwater (Na-HC $O_3$ type) shows a high pH (9.I~10.4) and relatively low TBS (72~116 mg/L). $CO_2$-rich water may have evolved by $CO_2$ added at depth during groundwater circulation. This process leads to the dissolution of surrounding rocks and Ca, Na, Mg, K and HC $O_3$ concentrations are enriched. The low Pc $o_2$ (10$^{-6.4}$atm) of alkali groundwaters seems to result from the dissolution of silicate minerals without a supply of $CO_2$. The $\delta$$^{18}$ O and $\delta$D values and tritium data indicate that two types of deep groundwater were both derived from pre-thermonuclear meteoric water. The carbon Isotope data show that dissolved carbon in the $CO_2$-rich water was possibly derived from deep-seated $CO_2$ gas. The $\delta$$^{18}$ S values of dissolved sulfate show that sulfate reduction occurred at great depths. The application of various chemical geothermometers on $CO_2$-rich groundwater shows that the calculated deep reservoir temperature is about 130~175$^{\circ}C$. Based on the geological setting, water chemistry and environmental isotope data, each of the two types of deep groundwater represent distinct hydrologic and hydrogeochemical evolution at depth and their movement is controlled by the local fracture system.m.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 2000년도 추계학술대회
• /
• pp.232-236
• /
• 2000

Multi-regression statistical analyses were applied for the water quality data of shallow alluvial ground water (n = 47) collected from the Youngdeok area, in order to quantitatively generalize the natural (non-anthropogenic) causes of regional water quality variation. Seven samples having the high contamination index ( $C_{a}$ > 3) reflect the striong effects by anthropogenic activity. Most of the alluvial groundwaters have acquired their quality primarily due to the dissolution of carbonate minerals. The results of multi-regression analysis show that chlorine is mainly derived from seawater effect. Sulfur isotopic compositions of dissolved sulfur and the S $O_4$/Cl ratio also enable us to discriminate the samples (n = 18) which are affected by atmospheric input of marine aerosol (sea-spray) and also by mixing between freshwater and seawater. Hydrogen and oxygen isotope data of the samples collected lie close to the local meteoric water line obtained from nearby Pohang city but has lower slope (5.45) on the $\delta$D-$^{18}$ O plot, indicating that alluvial groundwater was recharged from infiltrated meteoric water which has undergone some degree of kinetic evaporation. The estimated initial isotopic composition of the recharged water ($\delta$D = -74.8$^{0}$ /$_{00}$, $\delta$$^{18}$ O = -10.8$^{[-1000]}$ /$_{[-1000]}$ ) suggests that the alluvial ground water recharge largely occurs during summer storm events.s.s.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
• /
• pp.432-435
• /
• 2006

To evaluate geology and extent of leachate migration around the landfills, electrical resistivity survey were conducted in area of uncontrolled landfills in Cheonan and Wonju. The Cheonan landfill is located above the paddy fields and the resistivity survey lines were crossed to confirm possible pollution of the paddy fields by leakage of the landfill leachate. In Wonju, the landfill and the downgradient paddy fields are divided by a concrete barrier wall. At the bottom of the landfill, there is a leachate settlement system but has not been in operation. And a total of 4 survey line installed (1 parallel and 3 perpendicular to mean groundwater flow direction). According to the resistivity survey results, the landfill leachate in Cheonan appeared to be restricted only within the interior of the landfill, not to migrate into the subsurface of the paddy fields. These results are well consistent with electrical conductivity values of groundwaters obtained from a periodic analysis of water qualities. In Wonju, however, it was inferred that the leachate emanating from the landfill migrated beneath the abandoned leachate settlement system and it would reach the downgradient paddy field.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
• /
• pp.398-401
• /
• 2006

Two landfills of this study containing municipal wastes without any bottom liner and leachate treatment system have different landfill age, waste volume and most importantly different hydrogeologic settings. The one (Cheonan) is situated in an open flat area while the other (Wonju) is located in a valley. In the interior of the landfills, typical anaerobic conditions revealed by low DO and ${NO_3}^-$ concentrations, negative ORP values, high $NH_3$, alkalinity and $Cl^-$ concentrations were observed. Generally higher levels of contaminants were detected in the dry season while those were greatly lowered in the wet season. Significantly large decrease of Cl concentration in the wet season indicates that the dilution or mixing is one of dominant attenuation mechanisms of leachate. But detailed variation behaviors in the two landfills are largely different and they were most dependent on permeability of surface and subsurface layers. The intermediately permeable surface of 1.he landfills receives part of direct rainfall infiltration but most rainwater is lost to fast runoff. The practically impermeable surface of clayey silt (paddy field) at immediately adjacent to the Cheonan landfill boundary prevented direct rainwater infiltration and hence redox condition of the groundwaters were largely affected by that of the upper landfill and the less permeable materials beneath the paddy fields prohibited dispersion of the landfill leachate into downgradient area. In the Wonju landfill, there exist three different permeability divisions, the landfill region, the sandy open field and the paddy field. Roles of the landfill and paddy regions are very similar to those at the Cheonan. The very permeable sandy field receiving a large amount of rainwater infiltration plays a key role in controlling redox condition of the downgradient area and contaminant migration.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제15권6호
• /
• pp.9-16
• /
• 2010

Groundwater sampling was performed at 38 wells where they are located in the areas with high uranium and radon (marked as A and B, respectively) concentrations, which were based on the previous research results. In-situ parameters (temperature, pH, EC, Eh, DO) and natural radionuclides (uranium and radon) were analyzed to figure out the characteristics of groundwater environments. In-situ data did not show any relations to natural radionuclide data, which could be caused by groundwater mixing, depths of wells, and geological settings, etc. But the highest radon well presented relatively low temperature value and the highest uranium well presented relatively low pH values The highest uranium concentration ranging $1.14{\sim}188.19{\mu}g/L$ showed in the area of A region consisted of Jurassic two-mica granite. The areas of Jurassic biotite granite and Cretaceous granite in the A region have the uranium concentrations ranging $0.10{\sim}49.78{\mu}g/L$ and $0.36{\sim}3.01{\mu}g/L$, respectively. The uranium values from between wells of community water systems (CWSs) penetrating fractured bed-rock aquifers and personal boreholes settled in shallow aquifers near the wells of CWSs show big differences. It implies that the groundwaters of the two areas have evolved from different water-rock interaction paths that may caused by various types of wells having different aquifers. High radon activities in the area of B region composed of Precambrian gneiss showed ranging from 6,770 to 64,688 pCi/L. Even though the wells are located in the same geological settings, their rodon concentration presented different according to depth and distance.

• 지질공학
• /
• 제12권4호
• /
• pp.395-404
• /
• 2002

국내 먹는샘물의 수질기준치를 초과할 가능성이 있는 수질 항목에 대해 취수정의 심도와 지질을 연관시켜 고찰하였다. 5년 간(1998~2002)의 수질분석 결과에 의한 질산성질소의 평균 함량 범위는 0.8~1.09 mg/L, 불소의 평균 함량은 0.37~0.45 mg/h, 수소이온농도의 평균은 7.30~7.59이다. 이는 비슷한 도의 일반 지하수와 유사한 값을 보여서 천부 지하수의 유입 가능성을 지시한다. 전반적으로 이들 수질항목과 취수정의 심도, 지질과는 뚜렷한 관련성을 보이지 않는다. 먹는샘물의 평균 비소함량은 1999년의 0.0024 mg/L에서 2002년의 0.0066 mg/L으로, 비소 함량이 0.001 mg/L 이상인 먹는샘물 제조 업체의 비율도 1999년에 20.1%에서 2002년에 64.9%로 증가하고 있다. 2002년 현재, 향후 USEPA의 음용수 중 비소함량 기준으로 예상되는 0.01 mg/L을 초과하는 먹는샘물 제조업체 수는 57개소 중 11개소이다.

• 자원환경지질
• /
• 제34권2호
• /
• pp.175-192
• /
• 2001

동해안 울진 지역 천부 지하수의 수리지구화학 자료에 대하여 지구통계 분석(이원배치 분산 분석, 군집 분석, 요인 분석)을 수행함으로써, 수질 자료와 오염 특성의 시간적.공간적 변화 양상을 규명하고 대수층에서 일어나는 주요 반응을 고찰하였다. 이원배치 분산 분석 결과, 광역적 수질 특성은 8개 수계분지를 따라 유의한 공간적 변화를 보여주지 않았으나, Ca, HCO$_3$,SO$_4$등 일부 이온종은 수계분지별로 의미 있는 변화를 나타내었다. 시료 채취시기에 따른 계절 변화는 SO$_4$를 제외하고는 인지되지 않았다. 그러나 군집 분석 결과, 수리지구화학 특성의 변화는 해안으로부터의 거리에 따라 아주 잘 설명될 수 있음을 지시하였다. 요인 분석 결과, 연구 지역 천부 지하수의 수리지구화학 특성은 다양한 요인에 의해 지배됨을 확인하였다. 중요 순서로 그 요인을 나열하면, 1) 물-암석 반응(주로 탄산염 광물의 용해), 2) 바다에서 기원한 해염의 혼입, 3) 비료와 각종 농화학 약품에 의한 오염으로 밝혀졌다.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제19권6호
• /
• pp.37-48
• /
• 2014

Lab scale rhizofiltration by using four plants was performed to investigate the uranium removal efficiency from groundwater. Lettuce (Lactuca sativa L.), Chinese cabbage (Brassica campestris L.), radish sprouts (Raphanus sativus L.) and buttercup (Oenanthe javanica) were cultivated during 3 weeks in the phytotron. Glass jar ($12cm{\times}12cm{\times}8cm$ for each), containing 350 ml of the artificially uranium contaminated solution was used for 72 hours of the rhizofiltration. In experiments with different initial uranium concentration ($18.00{\mu}g/L$, $31.00{\mu}g/L$, $84.00{\mu}g/L$ and $116.00{\mu}g/L$) in solution, more than 70% of the initial uranium were removed by using lettuce, Chinese cabbage and radish sprouts and the residual uranium concentration in solution maintained lower than USEPA water tolerance limit ($30{\mu}g/L$). From the rhizofiltration experiments at various pH conditions, the highest uranium removal for all four plants was acquired at pH 3 in solution. Rhizofiltration experiments testing two field samples of groundwaters having high uranium concentrations ($86.00{\mu}g/L$ and $173.00{\mu}g/L$) were duplicated and more than 83% of the initial uranium were removed from the groundwater within 72 hours of rhizofiltration by using radish sprouts, which, suggests that the rhizofiltration can be a useful process to remediate uranium contaminated groundwater in the field. After the rhizofiltration experiment, the SEM and EDS analyses for the root surface of the radish sprouts were conducted, suggesting that the main mechanism of the rhizofiltration for the removal of uranium from groundwater would be surface precipitation on the root surface of the plant.

• 자원환경지질
• /
• 제51권6호
• /
• pp.567-577
• /
• 2018

우리나라에서 수막재배가 주로 이루어지는 수변지역에서는 수막재배 성수기 말기에 지하수위 하강이 심하게 나타나는 문제점이 있으며, 이러한 지하수위 하강과 지하수 자원 고갈의 문제는 인근 하천수와의 연계 특성을 고려할 때 효율적으로 해결할 수 있을 것이다. 이 연구에서는 수막재배지에서의 지하수와 하천수와의 연계성 및 지하수 대수층에 미치는 하천수의 영향 범위를 논의하기 위해, 지하수의 토출온도, 지하수와 하천수의 산소 수소 안정동위원소 조성 변화 특성을 검토하였다. 연구지역은 딸기 수막재배지로 잘 알려진 논산시 광석면 왕전리 지역이며, 지하수와 하천수의 시료 채취는 2010년 2월부터 2011년 6월까지 실시되었다. 지하수의 수온 분포 패턴에 의하면, 하천수의 영향은 주로 수막재배지의 우측 부분에서 넓은 범위에 걸쳐 나타났으며, 좌측 부분은 하천 인근에서만 좁은 범위의 영향을 받고 있는 것으로 나타났다. 이러한 현상은 수막재배지 내에서 산출되는 지하수의 산소 수소 안정동위원소 조성에서도 유사한 양상으로 나타났다.