• Water for future
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• v.24 no.3
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• pp.49-60
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• 1991

As a second part of the study entitled "Field Measurement and Analysis of Fluvial Sediment in the Cheongmi-Strea", this study concerns mineralogical and contaminative characteristics of sediment particles collected at Wonbu-Gyo and Hanpyeong-Gyo in the Cheongmi-Stream. The mineralogical analysis of the bed sediment collected reveals that, in general , quarz is the most abundant mineral found in sands with feldspars and rock fragments in the next, which confirms what is known in the literature. The shape factor of sand particles is about 0.7, which also agrees to what is known in the foreign literature. The analysis also reveals that the clay particles collected are composed mainly of illite, kaolinate, and chlorite. The analysis of contamination reveals that there is no substantial difference between the contents of organic material and heavy metals in the surface water and those in the pore water beneath the river bed. It is because the sampling for this analysis was conducted right after the September flood during which the fresh top soil from the upstream watershed replaced the old bed sediment and pore water that would probably be more contaminated. The contents of geavy metals in the bed sediment of sand particles do not exceed those in the soils adjacent to the river. For fine sediment such as clays, however, the contents of heavy metals, especially of mercury and zinc, far exceed those in the soils adjacent to the river. These fine sediments are transported downstream in the form of wash load and deposited in part on flood plains, which could be a new source of contaminants.taminants.

• Journal of Korean Society of Forest Science
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• v.86 no.3
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• pp.324-333
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• 1997

The research has been made for the effects of the pollution by the abandoned coal mine drainage on the physical and chemical properties of soil, stream sediment and soil water. The soils overspreaded by the abandoned coal don't develop solum and the bulk density is $1.83g/m^3$, compared with $1.14-1.38g/m^3$ in the other forest soils. The soil pH range in coal bearing region ie, from 4.01 to 4.11 and non-coal bearing soil range is from 5.03 to 5.13. Heavy metals such as As, Cr, Ni, Mo and Ba of coal bearing soils and polluted stream sediments have larger concentration than those of non-coal content and non-polluted. Especially As and Mo concentrations are largely high in coal bearing. The relative ratios $K_2O/Na_2O$ of geochemical elements are higher in coal bearing soil and polluted stream sediments than those of non-coal bearing soils and non-polluted stream sediments as well as black shales of the Changri Formation. However, $MgO+Fe_2O_3+TiO_2/CaO+K_2O$ are the opposite trends, so that the ratios are lower in the polluted regions. The soil water pHs in the polluted regions are the strong acid(pH3.4-4.2) and buffer capacity of the polluted soil is low because canons such as $Na^+$, $K^+$, $Mg^{+2}$are leached by the acidification.

• Journal of Ocean Engineering and Technology
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• v.22 no.6
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• pp.1-6
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• 2008

Anchors have been commonly used to as foundation systems of the structures that require the uplift resistance. Recently anchors have been used in ocean sediment for mooring systems to stabilizeoffshore structures. In the saturated clayey soil however suction developed between the soil and andchor and affects the uplift capacity of anchor. To estimate the uplift capacity of the andchor accurately, the failure mechanisms of the andchor by the uplift force should also be correctly assumed. The uplift capacity is usually expressed in terms of breakout factors with respect to embedment ratio. In this paper, a two-dimensional plane strain numerical investigation into the vertical uplift capacity of a plate andchor in a clayey soil is described. The breakout factor against their corresponding values of embedment ratio was calculated and plotted along a single curve. The modes of failure mechanism at shallow and deep andchors are also presented.

• Journal of Soil and Groundwater Environment
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• v.17 no.6
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• pp.119-128
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• 2012

The applicability and accuracy of Revised Universal Soil Loss Equation (RUSLE) model on the estimation of soil loss at impacted area of shooting range was tested to further the understanding of soil erosion at shooting ranges by using RUSLE. At a shooting range located in northern Kyunggi, the amount of soil loss was estimated by RUSLE model and compared with that estimated by Global Positioning System-Total Station survey. As results, the annual soil loss at a study site (202 m long by 79 m wide) was estimated to be 2,915 ton/ha/year by RUSLE and 3,058 ton/ha/year by GPS-TS survey, respectively. The error between two different estimations was less than 5%, however, information on site conditions should be collected more to adjust model coefficients accurately. At the study shooting range, sediments generated by rainfall was transported from the top to near the bottom of the sloping face through sheet erosion as well as rill erosion, forming a gully along the direction of the storm water flow. Coarser fractions of the sediments were redeposited in the limited area along the channel. Distribution characteristics of explosive compounds in soil before and after summer monsoon rainfall in the study area were compared with the erosion patterns. Soil sampling and analyses results showed that the dispersion of explosive compounds in surface soil was consistent with the characteristics of soil erosion and redeposition pattern of sediment movements after rainfalls.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1541-1545
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• 2006

본 연구의 목적은 내장저수지의 장래 퇴적량 및 퇴적분포를 추정하는 것으로 연구 결과는 다음과 같다. 1) 내장저수지 유역의 장래 토양유실량을 추정하기 위해 Landsat-5 TM 1984년 영상과 2001년 영상을 분석하여 토지이용변화를 알아보고, 연간 토양유실량 변화를 추정하였다. 2) 내장저수지 유역의 토양유실량을 추정하기 위하여 범용토양유실공식(USLE, Universal Soil Loss Equation)을 이용하였으며, 담수호로 유입되는 양을 추정하기 위하여 유사운송비법을 사용하였다. 담수호로 유입된 유사량 중 퇴적되는 양을 추정하기 위하여 유사량-포착효율법을 이용하였다. 3) 토양유실량의 연평균증가율을 바탕으로 장래 유입 유사량 및 퇴적량을 예측하였으며, Lara법에 의한 수위-내용적 관계 및 표고별 퇴적분포를 추정하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.1920-1924
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• 2007

본 연구에서는 SWAT 모형의 임하댐 유역에 대한 적용을 통하여 토사 유출 모의와 관련된 주요 매개변수들을 보정하고, 보정된 매개변수를 적용하여 유역에 대한 토사 유출을 분석하였다. 모형 구성 자료로는 임하댐 유역 청송, 영양, 부남, 석보, 일월의 1997년부터 2006년까지의 10년간의 강우자료를 사용하였으며 DEM도와 토지이용도, 토양도를 이용하여 유역 모델을 구축하였다. 유출 보정 자료로는 임하댐 일 유입량과 낙동강 오염총량제 지점인 반변과 용전 지점의 일유출량을 이용하였다. 특히, 임하댐에 유입되는 토사량에 대한 토사 유출 성향을 분석하여 유역의 토사 전달율(Soil Delivery Ratio)과 토사 발생지도(Sediment yield map)를 제작하여 각 소유역에 대한 토사 유출 관리를 위한 기초 자료로서 사용하게 될 것이다.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2010.04a
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• pp.383-385
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• 2010

This study analyzed the change of flowout and suspend solid in Andong and Imha basin according to the climate change to develop evaluation index about turbid water occurrence possibility and to support the countermeasures for turbid water management using GIS-based Soil and Water Assessment Tools (SWAT). MIROC3.2 hires model values of A1B climate change scenario that were supplied by Intergovernmental Panel on Climate Change (IPCC) were applied to future climage change data. Precipitation and temperature were corrected by applying the output value of 20th Century Climate Coupled Model (20C3M) based on past climate data during 1977 and 2006 and downscaled with Change Factor (CF) method. And future climate change scenarios were classified as three periods (2020s, 2050s, 2080s) and the change of flowout and suspended solid according to the climate change were estimated by coupling modeled value with SWAT model.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.368-368
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• 2022

The Soil and Water Assessment Tool (SWAT) has been widely used to simulate the long-term hydrological conditions of a catchment. Two output variables, outflow and sediment yield have been widely investigated in the field of water resources management, especially in determining the conditions of ungauged subbasins. The presence of missing data in weather input data can cause poor representation of the climate conditions in a catchment especially for large or mountainous catchments. Therefore, in this study, a custom module was developed and evaluated to determine the efficiency of utilizing basic spatial interpolation methods in the estimation of weather input data. The module has been written in Python language and can be considered as a pre-processing module prior to using the SWAT model. The results of this study suggests that the utilization of the proposed pre-processing module can improve the simulation results for both outflow and sediment yield in a catchment, even in the presence of missing data.

• Journal of the Korean GEO-environmental Society
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• v.9 no.4
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• pp.47-52
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• 2008

In this study, it was analyzed the soil components and elution characteristics of heavy metal ions in sediment samples to examine the effect of sediments embedded in Andong and Imha reservoirs on water quality. Major elements of sediments were shown to be Al, Si, K, and Fe by EDS analysis and major soil components of the collected 6 different sediments were illite (I), kaolinite (Ka), quartz (Q) and feldspar (F). And especially quartz took up a considerable part of sediments by XRD analysis. The total concentrations of Zn, As, Cr, Cu and Pb in sediments of Andong reservoir were relatively higher than those of Imha reservoir. The elution property of heavy metal from sediments had various aspects according to pH. Among the heavy metals in Andong reservoir sediments, As and Zn were significantly eluted at pH 6 compared with the other heavy metals. In the case of the adsorption tests using the sediments, the adsorptive capacities of Zn, Cd and Cu were very weak, on the while those of Pb and Cr were high.

• Nuclear Engineering and Technology
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• v.54 no.6
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• pp.2230-2243
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• 2022

The tin tailing processing industry in Malaysia has operated with minimal regard and awareness for material management and working environment safety, impacting the environment and workers in aspects of radiation and heavy metal exposure. RIA was conducted where environmental samples were analyzed, revealing concentrations of ²²⁶Ra, ²³²Th and ⁴⁰K between the range of 0.1-10.0, 0.0-25.7, and 0.1-5.8 Bq/g respectively, resulting in the AED exceeding UNCEAR recommended value and regulation limit enforced by AELB (1 mSv/y). Ra_eq calculated indicates that samples collected pose a significant threat to human health from gamma-ray exposure. Assessment of heavy metal content via pollution indices of soil and sediment showed significant contamination and enrichment from processing activities conducted. As and Fe were two of the highest metals exposed both via soil ingestion with an average of 4.6 × 10^-3 mg/kg-day and 1.4 × 10^-4 mg/kg-day, and dermal contact with an average of 5.6 × 10^-4 mg/kg-day and 6.0 × 10^-4. mg/kg-day respectively. Exposure via accidental ingestion of soil and sediment could potentially cause adverse non-carcinogenic and carcinogenic health effect towards workers in the industry. Correlation analysis indicates the presence of a relationship between the concentration of NORM and trace elements.