• Journal of Korean Society of Environmental Engineers
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• v.28 no.5
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• pp.463-471
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• 2006

Electrical resistivity surveys were conducted at areas of abandoned landfills in Cheonan and Wonju. Geology and extent of leachate migration around the landfills were evaluated with collected resistivity data by 2-D and 3-D resistivity inverse modeling. The Cheonan landfill is located above the paddy fields and the resistivity survey lines were crossed to examine possible pollution at 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, which has not been in operation. To evaluate leachate leakage into the paddy fields, a total of 4 survey lines were used. 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 the leachate would reach the downgradient paddy fields. Low resistivity area was observed in the old reservoir area and it appeared to be derived from convergence of groundwater flows from the surrounding valley and the moist wet land. In addition, groundwater flow into the paddy fields occurs beneath the old reservoir embankment at depths of $7{\sim}8m$. This paper reports details of the resistivity surveys for the uncontrolled landfills.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.303-306
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• 2002

변위가 발생한 해안도로 옹벽에 대한 원인을 규명하기 위하여 기반암과 매립부 지반에 대한 조사를 실시하였다. 연구지역에서 지질구조선의 발달은 관찰되지 않고 지표에서 기반암의 거동은 낙석의 형태로 나타난다. 기반암은 생교란작용의 유무에 따라 상, 하부지층이 구분되며 하부 지층은 신선한 상태로 이완된 불연속면은 나타나지 않는다. 변위는 옹벽의 이음부에 집중되며 옹벽의 운동방향은 우향이동과 좌향이동이 반복되며 최초 변위 발생지점 (시 점부)에서 멀어짐에 따라 장력에 의한 확장 (벌어짐)이 우세하며 종점부에서 회전운동이 수반된다. 이음부의 확장과 회전은 최초 발생 지점에서 응력이 전달되는 과정에서 나타난 것으로 해석된다. 매립부 지반의 전기비저항탐사에서 상부의 매립층은 높은 전기비저항을 가지는 것에 반해 하부는 매우 낮은 전기비저항 값을 보여준다. 이는 매립부의 하부지반이 해수면 이하에 위치하여 해수와 같은 유체의 영향을 받으나, 상부는 유체의 영향을 거의 받지 않는 것으로 추정된다. 반면 최초 변위가 발생한 지점의 매립부 지반은 하부와 같이 낮은 전기비저항 값을 보여준다. GPR 탐사에서 최초 변위 발생 지점에서 매질의 이완 내지 공동으로 추정되는 구조가 관찰된다.

• Journal of the Korean GEO-environmental Society
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• v.1 no.1
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• pp.13-18
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• 2000

The purposes of this study are the analysis of landfill gases(LFGs) in old open dumping landfill site near middle city and offer the useful data for reusing the landfill site as the residental, commercial and other purposes. The concentration of $CO_2$ and $CH_4$ were lower as 8.28 vol% and 1,247 ppm but the concentrations of $NH_3$ and $H_2S$ were 7 times and 12 times higher than TLV-TWA standard. The concentration of $CH_4$ and other gases were lower than the ACGIH criterion. As the result of the environmental assessment on the open dumping landfill, if appears that this landfill is maturation phase and the formation of LFGs is reduced. If the treatment facility of $NH_3$ and $H_2S$ gases is prepared, it can be safely used as this landfill site.

• Journal of the Korean Society of Groundwater Environment
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• v.6 no.2
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• pp.101-106
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• 1999

Open dump of refuse causes groundwater and soil contamination by leachate and air pollution by LFG(Landfill Gas). In this paper, in order to perform a study about reduction of high leachate and LFG collection & control, using a 3-D, 2-phase, transient FDM model, the analysis of simultaneous flow of leachate and LFG has been carried out. In present numerical analysis it is assumed that 58 percents of LFG will evaporate to the ambient air and the recharge rate of a landfill be 12 percent of the average precipitation per year. All other data were excerpted at the point of 1995 when three refuse layers had been buried. From numerical analysis we concluded that maximum head value is approximately 26 mH2O<-에이치투오 (2.52 atm) in the center of the system and that installing venting trench plays an important role in landfill stabilization. Evan with the assumption of three layers constructed and low recharge rate applied, it is found that cumulative leachate and LFG productions will be 15.1 million 세제곱미터, 5.58 billion 세제곱미터, respectively after 40 years.

• Journal of the Korean Geosynthetics Society
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• v.14 no.4
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• pp.97-104
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• 2015

When carrying out design for soft ground improvement before reclamation of dredged soil, it is very important to appropriately evaluate design parameters such as compression index and undrained strength in order to estimate optimum construction cost. In this study, consolidation and strength parameters were estimated by the samples obtained from the similar reclaimed land. Water content and compression index of dredged soil reclaimed by hydraulic fill method were quite decreased in comparison with those of in-situ conditions at Incheon site. Relationships between compression index(Cc) and water content (wn), and between undrained strength (su) and water content (wn) for dredged soil were obtained by field vane test and oedometer test, respectively. Applicability of Schmertmann correction method (compression index) for low plasticity silty soil was discussed according to comparison with designed and measured settlements.

• The Journal of Engineering Geology
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• v.16 no.4 s.50
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• pp.455-463
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• 2006

The electrical resistivity prospecting method with dipole-dipole array was applied to the Mooreung landfill site in order to survey the existence of leachate around the landfill site. Moreover, if there is leachate within Mooreung landfill site, the analysis of potential pathways to exterior environments was tried. Within the landfill site, the over-all characteristics of the electrical resistivity anomalies suggest that the leachate induced from the landfill materials has infiltrated the basement rock and fill the pores of basement rock in some parts of the landfill site. The consistency of the anomaly locations (left part of each survey line), anomaly geometries, and absolute resistivity value of anomaly through the 3 survey lines suggests that the resistivity anomaly be connected from the upstream to the downstream and correspond to the leachate material. Finally, the result from the electrical resistivity survey line near the gateway of the landfill site suggests that some of the leachate induced from landfill material leaks to the exterior groundwater system. It is necessary that more surveys using both geochemical and geophysical methods should be performed to find out potential pathways and depths of the leachate more precisely.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.4
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• pp.39-48
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• 2016

An information management system for a solid waste landfill site was developed, in this study, to optimize the operation and management of solid waste landfill in real time in addition to provide the information of landfill status to the landfill operator, public official concerned and local residents. The landfill information management system is composed of two systems (Solid waste landfill history management system and landfill operation and performance management system). The solid waste landfill history management system based on automated RFID/LPR system allows landfill operators to provide information of waste collection vehicles and received waste. In addition, the system aids in the identification of 3-dimensional (3D) position for landfilled solid wastes. Using the landfill operation and performance management system based on 3D laser scanner delivers information about landfill volume, settlement, landfill density, and current landfill capacity to landfill operators in real time, resulting in optimum space utilization. Ultimately, this system would dramatically reduce exposure of landfill operators to hazardous materials and improve the productivity of landfill operations.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.4
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• pp.189-197
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• 1993

The management of wastes within the urban landscape has become a critical concern to both local governments and inhabitants. With landfill capacities steadily decreasing, rapid growth of economy, population and urbanization, citizen awareness of the environment and public health problems occured by existing landfill sites make difficulties in selecting the landfill site. Therefore, this study has been performed to select the optimum waste landfill site using GSIS methodology to reduce the time, cost and effort. As the result of this study, we can investigate many factors synthetically which could not be handled by the former method using hands in the site selection for waste landfill, and we can carry out economically the work of selecting suitable site throughout the vast area.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.376-376
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• 2015

거주지나 공장부지와 같은 이용 가능한 토지를 만들기 위하여 해안 지역을 매립하는 토목공사가 전세계 곳곳에서 이루어지고 있다. 매립공사에서 매립토량의 결정은 경제성 부분에서 매우 중요하나 국내는 어항 항만 설계기준(2014)에 의하여 단순히 입경별로 유실율과 유보율을 산정하여결정하고 있는 실정이다. 따라서 본 연구에서는 원형의 매립호안 주변의 유사 거동을 분석하기 위하여 수리실험을 통한 연구를 진행하였다. 수리실험은 길이 13.0 m, 폭 5.0 m, 수위 0.10 m의 직사각형 단면의 개수로에서 수행되었으며, 실험에 사용된 유사는 주문진사($d_{50}=1.0mm$)와 안트사이트($d_{50}=0.44mm$)를 사용하였다. 원형 호안은 방수처리가 되어있는 목재로 제작하였고 두 가지 유사 모두 매립지역에서 형성되는 모래의 형상은 차이를 보였고 일정량의 유사가 호안 하류측에 쌓이는 것으로 나타났다. 선행 연구와 달리 호안에서 형성되는 모래의 이송된 형상을 관측하였다. 향후 모래 유입 위치를 달리하여 퇴적된 모래의 형성을 정량적으로 관측이 가능하다면 매립공사의 경제성을 높일 수 있을 것이라 기대된다.

• Geophysics and Geophysical Exploration
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• v.6 no.3
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• pp.143-152
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• 2003

Among the various geophysical approaches to identify the leakage of leachate with conductivity variation, conventional electrical resistivity survey has been mainly used at waste landfill. We adopted small-loop electromagnetic (EM) survey using multi-frequencies in parallel with electrical resistivity survey to delineate the leakage of leachate through the shallow soil layer at a waste landfill in Jeju Island, and also with self-potential monitoring to detect the streaming potential produced by the movement of leachate. There were no evidences of leakage from waste landfill according to the results of the electrical resistivity survey and SP monitoring, and it was also true from the results of water quality analysis at stream around waste landfill periodically. On the other hand, the results of one-dimensional inversion of spatially-filtered small-loop EM survey data showed the anomalous zone of low resistivity with depth both around and inner waste landfill.