• Journal of Korean Society of Environmental Engineers
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• v.34 no.6
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• pp.430-437
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• 2012

In order to obtain information on the design parameters of the horizontal laterals in floodplain filtration, laboratory-scale sand-box experiments were performed where the head distributions on the laterals and the groundwater profiles were measured according to the change in parameters including lateral diameter, hydraulic conductivity of the sand, water level at the well and raw-water supply rate. Measured data were analyzed using a numerical code in order to identify the discharge intensity distribution along the laterals. It was observed from the result that the lowering of the water level at the well had minimal adverse effect on the performance of the floodplain filtration. Results also elucidated that the low conveyance of the laterals to transmit the filtrate was compensated and supplemented by a natural augmentation in horizontal conveyance through the aquifer when the raw-water supply rate exceeded the adequate recovery rate. With this mechanism, the water quality is expected to improve further since the travel distance through the aquifer is amplified. Based on these findings it can be suggested that the diameter of the lateral used in the floodplain filtration may be smaller than those in riverbank/bed filtration. It was also found that the ratio between the head loss occurring in a lateral and the total head loss in the floodplain filtration was proportional to the exit velocities of the laterals, which may be used to design and/or evaluate the lateral in floodplain filtration.

• Applied Biological Chemistry
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• v.45 no.2
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• pp.84-91
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• 2002

If contaminated river water is sprayed over the floodplain, organic matter and nitrogen would be removed by microbial processes in the rhizosphere of vegetation during the filtration through soil. In this study we tested the organic matter and nitrogen removal from contaminated river water by the floodplain filtration. Model system of floodplain was constructed using a PVC pipe (15 cm i.d. ${\times}$ 150 cm L) which was packed with a loamy sand soil collected from a floodplain in Nakdong river. The model system was instrumented with soil solution samplers and gas samplers. A river water collected from Omogcheon in Kyongsan was sprayed from top of the model system at three different rates. The concentration of organic matter, DO, $NO_3^-$, $NO_2^-$, $NH_4^+$, $N_2$ and $N_2O$, and redox potential were measured as a function of soil depth for 24 days after the system reached a steady state. When river water was sprayed at the rates of 40.8 and 68.0 $l/m^2/day$, a significant reductive condition for denitrification was developed at below 5-cm depth of the soil. When the water reached at 90-cm depth of the soil, COD and concentration of inorganic nitrogen were lowered, on an average, from 18.7 to 5 mg/l and from 2.7 to 0.4 mg/l, respectively. $N_2$ comprised most of the N gas evolved from denitrification and $N_2O$ concentrations emitted at the surface of soil were less than 1 {\mu}l/l. The effective removal of organic matter and nitrogen by the filtration in the model system of floodplain demonstrates that the native floodplains, which include rhizosphere of vegetation at the top soil, could be more effective in the treatment of contaminated river waters and other industrial waste waters containing high concentration of organic matter and nitrogen.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.438-442
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• 2004

국가적인 수자원 다변화 정책의 일환으로 충적층을 활용한 강변여과, 지하수댐, 직접 함양 등의 다양한 충적층 지하수 인공함양 활용 가능성이 점차적으로 증대되고 있지만, 국내에서는 이를 구체적으로 활용하기 위하여 필요한 충적층 지하수의 개발 및 관리를 위한 충적층 수문지질도를 찾아보기 힘든 실정이다. 따라서, 본 발표에서는 부여 군수리 지역을 시범 대상 지역으로 선정하여 수자원 개발을 위한 충적층 활용 가능성을 평가하기 위해 기본적으로 필요한 지형적, 지질학적, 수리적 및 환경적 요소들을 포함하는 시범 충적층 수문지질도를 작성하였다. 본 충적층 수문지질도에는 지하수위 및 수질 변화, 지표 토양조건 및 지하 대수층 분포 등를 추정할 수 있는 다양한 자료들을 포함하고 있으며, 대부분의 이들 자료는 직접 현장 조사를 통해 획득되었다. 이러한 시범 충적층 수문지질도의 작성은 향후 충적층 지하수의 개발 및 관리시에 기본 자료로 활용될 것이다. 그러나, 앞으로 보다 정밀하고 효용성 있는 충적층 수문지질도 작성을 위해서는 이번 시범 작성을 참조하여 보다 많은 개선과 표준화가 요구된다.

• Journal of Soil and Groundwater Environment
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• v.17 no.3
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• pp.10-20
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• 2012

The pumping capacity of riverbank filtration using radial collector wells at the Geum, Yeongsan, Seomjin, and Nakdong rivers was evaluated using Milojevic's equation. Assessment of the radial collector wells' pumping capacity in riverbank filtration was carried out using a case study in which one set of collector wells is installed in the watershed of each river. Nakdong River was evaluated to have the highest pumping capacity for riverbank filtration. The areas capable of producing over 10,000 $m^3$ per day were found mostly in the Nakdong River.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.120-120
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• 2017

최근 국내 소비자들의 안전한 음식과 환경문제에 대한 관심이 높아지면서 재배작물과 경작지 토양의 물리 화학적 특성 등에 맞추어 적정 시비 및 재배관리를 적용하는 정밀농업이 시도되고 있다. 정밀농업은 농약 및 비료 등의 양을 적절하게 사용하여 생산 비용을 절감할 수 있으며, 과다사용을 막아 환경오염을 줄일 수 있다. 현재 토양의 수분, EC, pH등과 같은 항목은 신속하고 간단하게 분석이 가능하지만 토양의 필수 원소인 N, P, K 성분을 분석하는 제품은 상용화 되지 않았거나 가격이 비싸 일반 농가에서는 사용이 어렵다. 특히, 토양의 인을 현장에서 분석하기 위한 연구가 많이 수행되고 있으나 실제로 현장에서 사용되는 경우 또한 없는 상황이다. 일반적으로 토양에 포함되어 있는 인을 측정하기 위해서 많은 실험실에서는 이화학적 분석법을 사용하고 있다. 하지만 이 분석법은 오랜 시간과 전문적인 인력이 필요하며 주변 환경변화에 민감하여 실시간으로 분석하기에는 어렵다고 한다. 따라서 본 연구에서는 현장에서 실시간으로 토양의 인을 분석하기 위해 반자동 분석시스템을 제작하고 이를 검증하고자 하였다. 이전 연구에서 현장 토양을 이용한 신속측정법의 가능성($R^2>0.7$)을 확인하여 이 분석법을 바탕으로 반자동 분석시스템을 제작하였고 표준결과 값의 약 70% 이상의 수준을 목표로 하였다. 진주 지역의 현장 토양 20개 샘플과 반자동 침출 장치, 여과 장치, 발색 장치 그리고 통합 반자동 시스템을 이용하여 분석한 후 표준 분석 결과와 비교하였을 때 $R^2$ 값이 각각 0.985, 0.817, 0.893, 0.837로 약 70% 이상의 수준을 달성하였다. 추후, 반자동 토양 인 신속측정시스템을 완전 자동화 시스템으로 개발하고 주행 장치를 부착시켜 현장에서 실시간으로 원하는 위치의 인을 측정 할 수 있을 것으로 판단된다.

• Applied Biological Chemistry
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• v.38 no.3
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• pp.263-268
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• 1995

A study was undertaken to compare degradation patterns of carbofuran in soils between submerged and upland moisture conditions [$3-^{14}C$]Carbofuran was treated in each soils at the rate of 1.0 mg/kg (87.8 kBq $^{14}C/50g$ soil) and the time-course analysis for distribution of radioactivity and degradation products were conducted. Differences in the pathway and rate of carbofuran degradation in soils were observed between submerged and upland moisture conditiona major degradation being hydrolysis at 7-C position and oxidation at 3-C position, respectively. Carbofuran showed less persistence in soils of higher moisture contents A significant portion, $24{\sim}39%$ of the total radioactivity, resided in soils as nonextractable residues at 60 days after treatment The nonextractable radioactivity was mainly located in soil organic matter, fulvic acid, humic acid and humin factions Gel filtration chromatography confirmed the incorporation of carbofuran and its degradation products into the organic matter.

• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.2
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• pp.103-113
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• 2012

본 연구에서는 하수재이용에 따른 논에서의 토양염분 변화를 추정하기 위하여 경기도 화성시 수원환경사업소 인근에 위치한 병점지구를 대상으로 수문순환과 작물성장과의 관계를 고려한 SWAP (Soil-Water-Atmosphere-Plant) 모형을 이용하여 평가하였다. 실험에 사용한 관개용수는 지하수 (TR#1), 하수처리장 방류수+여과+UV (TR#3)로 분류하여 모형에 사용하였다. 유입관개수의 EC (Electrical Conductivity)는 지하수 관개수인 TR#1이 다른 처리구에 비해 작았고, TR#3의 경우 0.442~0.698 dS $m^{-1}$의 범위를 보였다. 모형의 보정과 검정을 위해서 대상지구에 FDR (Frequency Domain Reflection)을 설치하여 토양수분함유량과 염분농도를 토심에 따라 일단위로 모니터링 하였다. 토심 (50, 100, 140 cm)에 따른 토양함수량의 RMSE는 검정기간 중 TR#1에서 0.003~0.064 $cm^3\;cm^{-3}$, TR#3에서 0.001 $cm^3\;cm^{-3}$ 범위를 보여 주었고, 토양염분의 보정기간 중 토심별 RMSE는 TR#1에서 0.018~0.037 dS $m^{-1}$, TR#3에서 0.004~0.014 dS $m^{-1}$ 범위를 보여 적용성이 있는 것으로 나타났다. 토양내의 염분수지 분석 결과, 토양에서의 염분저장량이 (-)로 나타나 토양내로 침출되는 것으로 나타났으며, WMRI (Water Management Response Indicators)을 이용한 분석 결과, 높은 침투능으로 인하여 토양에서의 염분 집적 영향은 낮은 것으로 평가되었다.

• Journal of Soil and Groundwater Environment
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• v.16 no.6
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• pp.19-26
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• 2011

In this research, soil analysis and adsorption were conducted, and compared with the water quality of bank filtration and river in terms of TS, TDS, SS, $NH_4$-N, $NO_3$-N, $NO_2$-N, Fe, Mn, BOD and $KMnO_4$ consumption for the development of bank filtration in Gimhae city. Analysis of soil showed high levels of Fe (470 mg/kg), Mn (80 mg/kg) and $NH_4$-N (15 mg/kg). Also, adsorption coefficient values (k and 1/n) were 0.00159 and 0.8714, respectively. This implies that the adsorption of the soil depends on organic matter. Water qualitiy of the river and the bank filtration revealed that the concentrations of TS and TDS almost didn't change but the concentration of SS decreased 84% through the bank filtration. $NH_4$-N in the bank filtration was detected more than 1 mg/L which might be due to agricultural activities in the research area. $NO_3$-N was close to the detection limit owing to the removal by the adsorption. $KMnO_4$ consumption and BOD of the river were decreased by the bank filtration 250% and 350%, respectively, while Fe and Mn were significantly increased by the bank filtration.

• Journal of Korean Society on Water Environment
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• v.29 no.4
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• pp.489-496
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• 2013

Ground water underlying soil is vulnerable to pollution by organic chemicals through their percolation through the soil system. This study was conducted to provide information on the seepage behavior of organic chemical contaminants in clay, silty and sandy soils. Chloroform, 1,1,1-trichloroethane and trichloroethylene are readily transported through the soil; their percolated mass were 4.6-19.2 percent of the total mass applied. Tetrachloroethylene, 1,2-dichlorobenzene and 1,3-dichlorobenzene were retarded by soils due to sorption. Between 0.6 and 4.8 percent of the material applied to the surface percolated within the experimental period. Carbon tetrachloride was attenuated considerably by passage through soils. Only 0.1-0.4 percent of the mass reached the groundwater. Significant degradation of bromoform was observed. Apparent breakdown of intermediates of the brominated compounds were detected. Transformations of the brominated compounds appear to be the result of both biological and chemical processes. The effect of soil type on the mobility of organic chemical contaminants was considerable. The organic contaminants moved faster in sandy soil than in either clay or silty soils.

• The Journal of Engineering Geology
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• v.14 no.4 s.41
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• pp.391-400
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• 2004

Excess pumping on the river bank filtration well causes the over drawdown in the protected area of bank, which may make many problems such as soil water contents, Pumping head in the irrigated land, and it needs more irrigation and development of the deeper irrigating well. In this study the installation of the artificial recharging well was suggested to reduce the excess draw down in the protected land. Artificial recharging wells were applied at the bank filtration site of Changwon city by using Visual-MODFLDW. The optimized conditions are calculated that the recharging well is located about loom apart from the pumping well, and the recharging rate is $5\%$ of the pumping yield.