• Journal of Korea Soil Environment Society
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• v.2 no.3
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• pp.39-47
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• 1997

Geochemical study was carried out to find out the distribution of metals and cyanide in soil in the vicinity of the abandoned Daduck mine and the reason for acid mine drainage occurrence in the tailings impoundment. Chemical analysis showed that content of As in soil around tailings exceeded 15mg/kg, Korean standard of soil contamination in the farm land. That means the contamination of soil by As is due to input of tailings. According to total decomposition of tailings, As, Cd, Cu, Pb, Zn and S were highly concentrated in tailings. However the water in tailings impoundment was changed to acidic and contaminated by metals and sulfate because the tailings in the top of the tailings impoundment had been oxidized. Acid mine drainage contaminated the water course in the vicinity of the paddy soils. The proper measures are required to prevent contamination of the soil and water in the vicinity of the Daduck mine.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.1
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• pp.37-45
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• 2009

Susceptibility assessment of groundwater contamination is a useful tool for many aspects of regional and local groundwater resources planning and management. It can be used to direct regulatory, monitoring, educational, and policy-making efforts to highly vulnerable areas. In this study, a semi process-based was proposed to evaluate relative susceptibilities to groundwater contamination by nitrate on a regional scale. Numerical simulation based on data from each soil series was done to model water flow within soil profiles that were related to groundwater contamination by nitrate. Relative vulnerability indices for each soil series were produced by manipulation of amount of leaching flux, amount of average water storage in a soil profile, and amount of average water storage change. These indices were designed to convey the trend of leaching flux and to maximize spatial resolution. The resulting vulnerability distribution map was used to locate highly vulnerable sites easily with an appropriate grouping the indices, and was then compared with those from groundwater nitrate concentrations monitored. An excellent agreement was obtained across nitrate concentrations from the highly vulnerable regions and those from the low to stable regions.

• Journal of the Korean Association of Geographic Information Studies
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• v.6 no.2
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• pp.101-112
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• 2003

This paper designs and implements the management system that can calibrate the contamination vulnerability of the ground water, using an object oriented data model. Geographic-objects are specified by features extracted from an applicable geographic domain, and geographic-fields are defined by chemical factors extracted from each driven water. To show the topological relationships among the geographic-objects and the geographic-fields, this paper attach the weight and the ratio of the drastic model to chemical factors represented on the land use digital map and the ground water digital map. The geographic feature class, administrative boundary class, land use class and driven water class consist of a class composition hierarchy for evaluating the convenient contamination vulnerability calibration with spatial relationships among the well objects. Therefore, this management system for evaluating the contamination vulnerability can also contribute to the application of other natural environments.

• Journal of Radiation Protection and Research
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• v.27 no.3
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• pp.165-170
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• 2002

Combined with deposition model onto the ground of radionuclides, the influence of radioactive contamination to agricultural products was analyzed due to wet deposition as well as dry deposition from radioactive air concentration during a nuclear emergency. The previous dynamic food chain model, in which initial input parameter is only radionuclide concentrations on the ground, was improved for the evaluating of radioactive contamination to agricultural products from either radionuclide concentrations in air or radionuclide concentrations on the ground. As the results, in case of deposition onto the ground, wet deposition was more dominant process than thy deposition. While the contamination levels of agricultural products were dependent on the a variety of factors such as radionuclides and rainfall rate. It means that the contamination levels of agricultural products are determined from which is more dominant process between deposition on the ground and interception onto agricultural plants.

• Ecology and Resilient Infrastructure
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• v.2 no.3
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• pp.237-246
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• 2015

Heavy metal pollution in soil, such as lead contamination, has become an area of interest in Korea because of urbanization and atmospheric deposition from neighboring countries. Therefore, in this research, eco-physiological responses such as chlorophyll contents, antioxidant enzyme activity, photosynthetic rate, biomass and phytoaccumulation abilities were investigated for 4 commonly used native roadside tree species to suggest suitable tree species to cope with lead contamination. The target species, Ginkgo biloba, Prunus yedoensis, Zelkova serrata and Chionanthus retusus showed lead toxicity by significant changes of chlorophyll contents and antioxidant enzyme activities on treatments over 200 mg Pb/kg. However, biomass and photosynthetic rates only showed significant responses of plants in the highest level (5,000 mg/kg) treatment. Especially, G. biloba did not show any significant changes of antioxidant enzyme activity, photosynthetic rate, and biomass even in the highest level treatment. In low level - environmentally realistic treatments, G. biloba and P. yedoensis showed the highest phytoaccumulation rate of lead from soil. Selecting and planting species like G. biloba which have good phytoaccumulation abilities and resistance to lead contamination by further research will be required to deal with emerging lead contamination.

• The Journal of Engineering Geology
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• v.28 no.4
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• pp.727-740
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• 2018

The media in the undersaturated zone is defined as the uppermost layer of the water table at which the groundwater is unsaturated or saturated discontinuously. The properties of the unsaturated zone can affect the reduction of contaminants that flow from the lower part of soil to the water table. In recent, there have been problems in evaluating groundwater contaminations vulnerability because weighted value for permeability is given, regardless of anisotropy and heterogeneity in the unsaturated media. Geological media have various ranges of permeability. When applying the weighted value, representative of permeability for grain sizes standardized, to construction of contamination vulnerability, it will produce more exaggerated result than the case that considers unsaturated geological properties. In this study, we performed laboratory column tests considering two sets of the unsaturated layers in order to investigate the permeability in anisotropic unsaturated zone with anisotropy. On the basis of the tests, average permeability coefficients were calculated considering the properties of unsaturated media obtained from drill cores in the field. The final contamination vulnerability map constructed shows that the contamination vulnerability map applying the properties of geological media of the unsaturated zone coincides much better with the results measured in the field, compared to the case of contamination vulnerability considering the weighted value in the unsaturated zone.

• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.353-358
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• 2007

Contamination of ochratoxin A (OTA) was studied in 194 compound feeds and 59 feed ingredients samples distributed in South KOREA in 2006 and 2007. The degree of OTA contamination in feed ingredients was 27%, and its detected levels were ranged from 0.27 to 3.39 ppb. Seventy six percent of compound feeds were contaminated with OTA at concentration between 0.21 and 13.64 ppb. The highest degree of OTA contamination was observed in compound feeds for dairy cattle (96%) followed by for poultry (85%) and swine (79%). Beef cattle exhibited the highest level of OTA contamination (2.2 ppb). Compound feeds for dairy cattle and feed ingredients for vegetable proteins showed relative lower level of contamination at 1.6 and 1.2 ppb, respectively.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2333-2337
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• 2007

The practical studies on the method of particle contamination control for yield enhancement in the cleanroom were carried out. The method of the contamination control was considered, which is composed of data collection, data analysis, improvement action, verification, and implement control. The composition analysis for data collection and data analysis was used in the cellular phone module packaging lines. And this method was evaluated by the variation of yield loss between before and after improvement action. In case that the composition analysis was applied, the critical sources were selected and yield loss reduction through improvement actions was also investigated. From these results, it is concluded that the composition analysis is effective solutions for particle contamination control in the cleanroom.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2338-2343
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• 2007

The practical studies on the method of particle contamination control for yield enhancement in the cleanroom were carried out. The method of the contamination control was proposed, which are composed of data collection, data analysis, improvement action, verification, and implement control. The partition check method for data collection and data analysis was used in the cellular phone module production lines. And this method was evaluated by the variation of yield loss between before and after improvement action. In case that the partition check method was applied, the critical process step was selected and yield loss reduction through improvement actions was observed. From these results, it is concluded that the partition check method is effective solution for particle contamination control in the cleanroom production lines.

• Proceedings of the Korean Geotechical Society Conference
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• 1993.05a
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• pp.28-44
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• 1993

Remediation actions in uncontrolled landfill site should be conducted after the investigation of contamination status and potential health risk or damage. Based on the above, proper control measures should be established and operated. Also continuous monitoring should be followed. In this study, the status of ground water contamination around Nanji Landfill Site was investigated. Monitoring wells were installed around the landfill and ground water was sampled once a month and analyzed. Water quality of each monitoring well was different depending on the horizontal and vertical distance from the landfill, and the seasonal leachate characteristics were not significantly changed because percolating water stayed long time in the deep waste layer. It was predicted that major multivalent cations were mainly precipitated as metal carbonate form, and chemical mass balances (CMBs) could be applied for the apportionment of leachate contamination to ground water quality of surrounding areas of Nanji Landfill. Parameters required to estimate pollutant flux to the receptor near landfill were listed and discussion to get these parameters was made. Finally, based on the above data, control measures of ground water contamination were suggested and discussed.