• Economic and Environmental Geology
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• v.55 no.6
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• pp.717-726
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• 2022

This study was conducted to assess the geochemical contamination degree of As, Cd, Cu, Pb, Sb, and Zn in the soil and water samples from an abandoned gold mine. Enrichment Factor (EF), Geoaccumulation Index (Igeo), and Pollution Load Index (PLI) were carried out to assess the geochemical contamination degree of the soil samples. Variations of sulfate and heavy metals concentration in water samples were determined to identify the geochemical distribution with respect to the distance from the mine tailing dam. Geochemical pollution indices indicated significant contaminated with As, Cd, Pb, and Zn in the soil samples that areas close to the mine tailing dam, while, Sb showed similar indices in all soil samples. These results indicated that the As, Cd, Pb, and Zn dispersion has occurred via anthropogenic sources, such as mining activities. In terms of water samples, anomalies in the concentrations of As, Cd, Zn, and SO₄^2- was determined at specific area, in addition, the concentrations of the elements gradually decreased with distance. This result implies the heavy metals distribution in water has carried out by the weathering of sulfide minerals in the mine tailing and soil. The study area has been conducted the remediation of contaminated soil in the past, however, the geochemical dispersion of heavy metals was supposed to be occurred from the potential contamination source. Therefore, continuous monitoring of the soil and water is necessary after the completion of remediation.

• Economic and Environmental Geology
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• v.30 no.5
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• pp.407-416
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• 1997

Soil, tailings, stream sediment and surface water samples collected in the vicinity of the Geumwang Au-Ag mine were analyzed in order to investigate the pollution level of heavy metals and to determine the dispersion patterns. Although the maximum concentrations of soils collected at the flotation plant and tailings dam were 9,270 ppm As, 17 ppm Cd, 1,480 ppm Cu, 10,080 ppm Pb and 18,400 ppm Zn, dispersion of heavy metals were limited in the vicinity of the flotation plant and tailings dam. This may be due to high pH values (> 8.0) of the soils by flotation solution for mineral processing. The pH values of water samples near the flotation plant and tailings dam were over 8.0 and Cd, Cu and Zn concentrations were not detected. The waters in the vicinity of Geumwang mine generally belong to a $Ca^{2+}-SO_{4}{^{2-}}$ $(HCO_3{^-})$ type.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.6
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• pp.2773-2778
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• 2012

Formulation of finite difference method for analyzing seepage under concrete dam was carried out in order to find out characteristics of flow net. For the situation without curtain, slope of equipotential line of nonhomogeneous soil is greater in the region which has higher value of coefficient of permeability. By comparing analysis results between the situations with locating curtain at the center portion and left end, velocity of flow along with the face of the right hand side of the curtain for the situation with left end curtain is lower than that for the situation with center curtain. Considering flow in the region of the right of the curtain, streamline for the situation with left curtain gets horizontal relatively.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.1400-1405
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• 2008

Execute surface of the earth geological survey for stability analysis of stealing cutting sides and investigated wide area nature of soil structure. Inflected DIPS that measure discontinuity's direction that develop to slope and is slope stability a wide use program for Stereographic Projection Method analysis that utilize geometrical correlation of stealing four sides and discontinuity surface. It is principle that angle of internal friction that is basis element of stability estimation applies direct shear test result on joint side, Examination is impossible by case execution, suppose by 30 angles that apply more conservatively in base rock slope sides usually and achieved analysis. When analyze, consider discontinuity's various adult that develop in research slope, after conduct first each discontinuity different assay falling into fault, joint, executed stability estimation which synthesize whole discontinuity data. When ailment element is recognized as analysis result, wished to present stability countermeasure way of most suitable to take into account of execution, stability, economic performance.

• Magazine of the Korean Society of Agricultural Engineers
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• v.25 no.4
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• pp.69-79
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• 1983

The objective of this study is to analyze the present situation of compaction equipment used in the earth fill dam construction, and the compaction effects of varions types of equipment on core and pervious zones of the fill dam. The results obtained are summarized as follows; 1. Banking materials mostly used for the core zone were soils classified as CL, SC and ML, while those classified as SM, ML and SC were predominant for the pervious zone. 2. Equipments used practically in the real fields were considerably different from those specified in the designs. 3. It was found that the relationship between optimum water content and maximum dry density for both core and pervious materials showed to be linear, ranging from 10% to 25% water content. That is, ${\gamma}$dmax (core) = 2.2555-0.0284 Wopt ${\gamma}$dmax(pervious) =2.239-0.028 Wopt 4. The generalized compaction guides for all kinds of equipment and soil types consi- dered in this study may be recommended as N=8-10 T=2Ocm, N=10-12 T=3Ocm for core zone(98%) and N=6-8 T=2Ocm, N=8-10 T=3Ocm for pervious zone (95%). 5. The coefficient of permeability in the field tests showed abont 10 times as high as the laboratory test value. This large deviation, however, was due to the horizontal permeation and considered not to be significant in the light of the satisfactory compaction ratio in the field compac- tion.

• Structural Engineering and Mechanics
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• v.33 no.4
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• pp.407-428
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• 2009

The effects of the uniform and spatially varying ground motions on the stochastic response of fluid-structure interaction system during an earthquake are investigated by using the displacement based fluid finite elements in this paper. For this purpose, variable-number-nodes two-dimensional fluid finite elements based on the Lagrangian approach is programmed in FORTRAN language and incorporated into a general-purpose computer program SVEM, which is used for stochastic dynamic analysis of solid systems under spatially varying earthquake ground motion. The spatially varying earthquake ground motion model includes wave-passage, incoherence and site-response effects. The effect of the wave-passage is considered by using various wave velocities. The incoherence effect is examined by considering the Harichandran-Vanmarcke and Luco-Wong coherency models. Homogeneous medium and firm soil types are selected for considering the site-response effect where the foundation supports are constructed. A concrete gravity dam is selected for numerical example. The S16E component recorded at Pacoima dam during the San Fernando Earthquake in 1971 is used as a ground motion. Three different analysis cases are considered for spatially varying ground motion. Displacements, stresses and hydrodynamic pressures occurring on the upstream face of the dam are calculated for each case and compare with those of uniform ground motion. It is concluded that spatially varying earthquake ground motions have important effects on the stochastic response of fluid-structure interaction systems.

• Journal of Soil and Groundwater Environment
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• v.27 no.2
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• pp.36-40
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• 2022

To respond to rapidly changing water circumstances such as climate change, drought, etc., the korean government (MOE) established four advanced strategies for integrated groundwater management. The first strategy is watershed-based management of groundwater. The second strategy is total quantity management of groundwater including improvement of groundwater preservation area policy and procedure of investigation for groundwater influence area, additional construction of groundwater dam, installation of large-scale public wells, extention of spilled groundwater use. The third strategy is prevention of groundwater contamination including expansion of monitoring wells, introducing declaration of groundwater contamination. The last strategy is advancement of groundwater information management including integrated management of data, setting up a big-data based open platform. The above-mentioned four strategies will be reflected in the 4th National Groundwater Management Plan to secure implementation power, and it is expected to laid the foundation for advanced and rational groundwater management system.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.172-172
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• 2020

In recent years, soil erosion has come to be regarded as an essential environmental problem in human life. Soil erosion causes various on- and off-site problems such as ecosystem destruction, decreased agricultural productivity, increased riverbed deposition, and deterioration of water quality in streams. To solve these problems caused by soil erosion, it is necessary to quantify where, when, how much soil erosion occurs. Empirical erosion models such as the Universal Soil Loss Equation (USLE) family models have been widely used to make spatially distributed soil erosion vulnerability maps. Even if the models detect vulnerable sites relatively well by utilizing big data related to climate, geography, geology, land use, etc. within study domains, they do not adequately describe the physical process of soil erosion on the ground surface caused by rainfall or overland flow. In other words, such models remain powerful tools to distinguish erosion-prone areas at the macro scale but physics-based models are necessary to better analyze soil erosion and deposition and eroded particle transport. In this study, the physics-based Surface Soil Erosion Model (SSEM) was upgraded based on field survey information to produce sediment yield at the watershed scale. The modified model (hereafter MoSE) adopted new algorithms on rainfall kinematic energy and surface flow transport capacity to simulate soil erosion more reliably. For model validation, we applied the model to the Doam dam watershed in Gangwon-do and compared the simulation results with the USLE outputs. The results showed that the revised physics-based soil erosion model provided more improved and reliable simulation results than the USLE in terms of the spatial distribution of soil erosion and deposition.

• Journal of the Society of Disaster Information
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• v.18 no.4
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• pp.687-698
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• 2022

Purpose: This study was conducted to understand the public awareness of landslide and check dams in 2015-2020 using the big data platform 'Hyean' and to confirm the utilization of this platform in disaster prevention areas. Method: The total amount, number of detection by period by media, and affirmative and negative trends of a search for 'landslide' and 'check dam' in 2015-2020 were analyzed using a keyword search of 'Hyean.' Result: There is significant lack of public awareness of check dam compared to landslide, and the trend is more noticeable in the conspicuous gap of data amount between the news and SNS media. The number and the timing of the search for 'landslide' coincided with the actual occurrence of landslide, while the detection of 'check dam' was less related to it. Relatively affirmative preception for the check dam is inferred, but it was difficult to confirm accurate statistical affirmative and negative trends in the disaster prevention field using 'Hyean.' Conclusion: Unlike the experts who expect positive public awareness of check dam, the statistic results show that the public awareness of the check dam as an effective countermeasure against landslide was extremely low. Active promotion of erosion control projects should be carried out first, and a balanced sample survey should accompany online and periodic field surveys. Since there is a limit to grasping the effective perception in the field of disaster prevention area using 'Hyean', it should be very cautious to establish local/governmental policies using it.

• Magazine of the Korean Society of Agricultural Engineers
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• v.18 no.4
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• pp.4251-4258
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• 1976

In the construction of earth dam, embankment and highway by filling, a compaction contributes to increasing the density of soil by applying pressure. The effect of compaction depends on various factors such as soil type, moisture content, gradation, consistency, and compaction energy. In this study, the correlations amone maximum dry density, moisture content, dry density, and moisture content are analyzed. Some results obtained in this study are summarizep as follows. 1. The maximum dry density sinoreases with increased of optimum moisture content and the correlations of them can be represented by; ${\gamma}$dmx=a-b(W0) 2. Maximum dry density and liquid limit show negative linear correlation and can be represented by; ${\gamma}$dmx=a-b(LL). 3. Optimum moisture content and liquid limit, plastic limit show positive linear correlation and can be represented by the following equation, W0=a+b(LL) W0=a+b(PL). 4. Liquid limit and plastic limit show positive linear correlation, and can be represented by the following equation, LL=a+b(PL).