• Journal of Environmental Impact Assessment
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• v.28 no.2
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• pp.152-168
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• 2019

The element arsenic, which is abundant in the Earth's crust, is used for various industrial purposes including materials for disease treatment and household goods. Various human activities, such as the disposal of soil waste, metal mining and smelting, and combustion of fossil fuels, have caused the pollution of the environment with arsenic. Recently, guidelines for arsenic in rice have been adopted by the Korean ministry of food and drug safety to prevent health risks based on rice consumption. Because of the exposure to arsenic and its accumulation in the human body through various channels, such as air inhalation, skin contact, ingestion of drinking water, and food consumption, integrated multimedia risk assessment is required to adopt appropriate risk management policies. Therefore, integrated human health risk assessment was carried out in this study using integrated exposure assessment based on multimedia (e.g., air, water, and soil) and multi-route (e.g., oral, inhalation, and dermal) scenarios. The results show that oral uptake via drinking water is the most common pathway of arsenic into the human body, accounting for 57%-96% of the total arsenic exposure. Among various age groups, the highest exposures to arsenic were observed in infants because the body weight of infants is low and the surface areas of infant bodies are large. Based on the results of the exposure assessment, the cancer and non-cancer risks were calculated. The cancer risk for CTE and RME is in the range of 2.3E-05 to 6.7E-05 and thus is negligible because it does not exceed the cancer probability of 1.0E-04 for all age groups. On the other hand, the cancer risk for RME varies from 6.4E-05 to 1.8E-04 and from 1.3E-04 to 1.8E-04 for infants and preschool children, exceeding the excess cancer risk of 1.0E-04. The non-cancer risks range from 5.4E-02 to 1.9E-01 and from 1.5E-01 to 6.8E-01, respectively. They do not exceed the hazard index 1 for all scenarios and all ages.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.2
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• pp.214-219
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• 2007

66 micropollutants analyses in 9 wastewater treatment plants(WWTPs) along Nak-dong river were implemented to identify the concentrations and removal efficiencies before and after treatment processes. As a result of study, the concentration levels discharged from WWTP effluents to water system were below the water quality criteria and the levels of other studies. The removal efficiencies were 84.6%(DAF/CCR) and 81.6%(AC) for 1,4-dioxane. Phenol, Clphs and PAHs were removed 94.6%, 66.4% and 80.6% respectively by the activated sludge(AS) process. The removal efficiencies of Clbzs were 45.3% for the activated sludge(AS) process and 60.6% for the activated carbon(AC) process. However, other processes besides AS and AC, the removal efficiencies of Clbzs were very low(<20%). The sand filtration(SF) process that could remove particle matters showed the best efficiency for PCDDs / Fs removal$(\geq99%)$. However, in case of relatively low PCDDs/Fs concentration level in influent, the removal efficiency was not so high$(\leq50%)$.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.3
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• pp.533-544
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• 2015

Unlike the concrete structure built on land, that exposed to the marine environment is greatly degraded in durability due to the exposure to not only the physical action caused by sea wind, tide, and wave, but also the harsh conditions, including the chemical erosion and freeze-thaw which result from $SO_4{^{2-}}$, $Cl^-$ and $Mg^{2+}$ ions in seawater. In the process of the large scaled construction of submerged concrete structures, of course environmental hazardous substance, such as alkaline (pH) and heavy metals, may be leached. Thus, this issue needs to be adequately reviewed and studied. Therefore, this study attempted to develop a CSA (Calcium Sulfo Aluminate) activator using electric arc furnace reducing slags, as well as the eco-friendly concrete for artificial reefs using electric arc furnace oxidizing slag as aggregate for concrete. The strength properties of the eco-friendly concrete exposed to the marine environment were lower than those of the normal concrete by curing 28 days. This suggest that additional studies are needed to improve the early strength of the eco-friendly concrete. With respect to seawater resistance of the eco-friendly concrete, the average strength loss against 1 year of curing days reached 8-9%. the eco-friendly concrete using high volume of ground granulated blast furnace slags and high specific gravity of electronic arc furnace oxidizing slag demonstrated the sufficient usability as a freeze-thaw resistant material. With respect to heavy metal leaching properties of the eco-friendly concrete, heavy metal substances were immobilized by chemical bonding in the curing process through the hydration of concrete. Thus, heavy metal substances were neither identified at or below environmental hazard criteria nor detected, suggesting that the eco-friendly concrete is safe in terms of leaching of hazardous substances.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.6
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• pp.672-678
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• 2015

The types of hazardous and noxious substances (HNS) being transported by sea in Korea are at about 6,000, HNS transport volume accounts for 19% of total tonnage shipped in Korea, and the increase rate of seaborne HNS trade in Korea is 2.5 times higher than the average increase rate of the world seaborne HNS trade. Reflecting this trend, HNS spill incidents have been frequently reported in Korean waters, and there are increasing social demands to develop HNS management technology for the preparedness, response, post-treatment and restoration in relation to HNS spill incidents at sea. In this study, a risk-based HNS prioritization system was developed and an HNS risk database was built with evaluation indices such as sea transport volume, physicochemical properties, toxicities, persistency, and bioaccumulation. Risk scores for human health and marine environments were calculated by multiplying scores for toxicity and exposure. The top-20 substances in the list of HNS were tabulated, and Aniline was ranked first place, but it needs to be managed not by individuals but by HNS groups with similar score levels. Limitations were identified in obtaining data of chronic toxicity and marine ecotoxicity due to lack of testing data. It is necessary to study on marine ecotoxicological test in the near future. Moreover, the priority list of HNS is expected to be utilized in the development of HNS management technology and the relevant technologies, after the expert's review process and making up for the lack of test data in the current research results.

• Journal of Environmental Policy
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• v.4 no.2
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• pp.57-82
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• 2005

In this study, we propose methods for. the efficient management and integrity of groundwater in response to a diminishing supply. As an alternative water resource for the future. we investigated and comparatively analyzed the quality standards of groundwater in the US (New York, Wisconsin and Texas), Austria, Netherlands, Canada, Japan and United Kingdom. These developed countries heavily depend on groundwater, more than 70%, for drinking water and apply those drinking water standards to groundwater quality. However, there exists few differences in the quality standards of groundwater among the countries, because each country possesses its own individual environment and management. In Korea, surface water pollution is getting serious and its water resources are diminishing. Therefore we propose several new quality criteria that many countries regulate at these days for their efficient management of groundwater. There is a need to divide BTEX criterion into Benzene, Toluene, Ethylbenzene and Xylene, individually. In. addition, it is needed to establish BTEX criteria into agricultural water and industrial water use standards as well as daily life use standards. Also, regulations for some PAHs, showing carcinogenicity, are required. Due to rapid industrialization various hazardous chemicals were utilized and their uses are increasing each year. Therefore, there is a strong need to introduce n~w standards and tighter regulations of the levels. At the same time, the criterion of nitrogenous compounds need' to be regulated individually in order to prevent the damage incurred by the compounds. Several developed countries have established standards for radon, previously caused environmental accidents in Korea. Therefore, we propose the necessity of groundwater quality standards for radon in this study.

• Journal of Korea Multimedia Society
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• v.6 no.6
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• pp.1062-1070
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• 2003

In this paper, we observe one of the aquatic insect, fish(Medaka)'s behavior which reacts to giving toxic chemicals until lethal conditions using automatic tracking sl$.$stem. For the result, we define the Pattern A is a normal movement of fish and Pattern B is after giving the chemicals. In order to detect the movement of fish automatically, these patterns are selected for the training data of the artificial neural networks. The average recognition rates of the pattern B are remarkably increased after inputs of toxic chemical(diazinon) while the Pattern A is decreased distinctively. This study demonstrates that artificial neural networks are useful method for detecting presence of toxicoid in environment as for an alternative of in-situ behavioral monitoring tool.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.spc
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• pp.37-43
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• 2022

Post-spill monitoring of hazardous noxious substances accidents is essential in the event of a spillage of significant quantities of pollutants and for the management of the marine environment resulting from the long-term effects of the persistent toxic substances. The accidental introduction of a sinker into the marine environment can create harmful anaerobic conditions in the benthic ecosystem and spread over the seafloor by the topography and currents. Through case studies, most post-spill monitoring includes modeling, remote sensing, and chemical analyses of the sediment and benthic organisms. The monitoring also evaluates the effectiveness of restoration and recovery activities and assesses damages and compensation.

• Journal of the Korean GEO-environmental Society
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• v.2 no.1
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• pp.15-22
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• 2001

The key part in risk assessments for disposal sites of solidified/stabilized (S/S) wastes is to predict the contaminant transport from the S/S wastes to the environment under dynamically changing field conditions after characterizing chemical leaching properties of the ash, to evaluate the risk from the predictions, and finally to decide the risk is acceptable. In this paper, a risk assessment framework for disposal and reuse of S/S wastes was developed considering two limiting cases of contaminant leaching. Two types of waste characterization procedures that can determine waste-specific variables for the two limiting cases were developed and verified by applying them to a landfill site of the Municipal Solid Waste incinerator ash solidified/stabilized by cement.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.2
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• pp.206-218
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• 2020

Located mostly inside the megacity of Busan, the Busan Southern Port is a multifunctional port with various nearby industry activities, including a joint fish market, ship repair facilities, and fishing boat facilities. If toxic chemicals generated by the industrial activities continue to flow into and accumulate in the sediment of the port, they can affect aquatic ecosystems and humans. Therefore, in this study, distribution levels and potential influent sources of organic pollutants, including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and butyltin compounds (BTs), in the sediment were investigated. The sediment samples were collected from eight sampling sites in November 2013 (first phase) and November 2014 (second phase). The mean concentrations of PAHs, PCBs, and BTs in the first and second sampling phages were 4174.0 ng/g-dry wt. and 1919.0 ng/g-dry wt., 166.3 ng/g-dry wt. and 21 ng/g-dry wt., and 50.9 ng/g-dry wt. and 30.8 ng/g-dry wt., respectively. The concentrations of the organic pollutants detected in the seabed sediments were lower in the second phase than in the first phase. In this study, the inflow sources of PAHs, PCBs, and BTs were found to be combustion, land, and municipal sewage or industrial wastewater, respectively.

• Korean Journal of Remote Sensing
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• v.38 no.6_3
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• pp.1837-1846
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• 2022

The annual increase in chemical accidents is causing damage to life and the environment due to the spread and residual of substances. Environmental damage investigation is more difficult to determine the geographical scope and timing than human damage investigation. Considering the reality that there is a lack of professional investigation personnel, it is urgent to develop an efficient quantitative evaluation method. In order to improve this situation, this paper conducted a chemical accidents investigation using unmanned aerial vehicles(UAV) equipped with various sensors. The damaged area was calculated by Ortho-image and strength of agreement was calculated using the normalized difference vegetation index image. As a result, the Cohen's Kappa coefficient was 0.649 (threshold 0.7). However, there is a limitation in that analysis has been performed based on the pixel of the normalized difference vegetation index. Therefore, there is a need for a chemical accident investigation plan that overcomes the limitations.