• Korean Journal of Ecology and Environment
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• v.45 no.4
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• pp.459-473
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• 2012

This study evaluated the rainfall-runoff characteristics of Non-point Pollution Source (NPS) of the impervious area through on-site monitoring. In this study, trend analysis was performed by various runoff analysis method of non-point pollution source. The characteristics of rainfall at impervious area appeared to be influenced by rainfall strength. It is judged that the measure is required to be prepared against that now that concentration difference of non-point pollution source appeared to be big by precedent number of days of no rainfall. However, it appeared that Rainfall Sustaining Time (RST) has nothing to do with effluent concentration of non-point pollution source, however, the rising tendency that effluent concentration did not appear because the tendency that concentration of non-point pollution source reduces more than 50% within initial 60 min due to first flushing effects and rainfall sustaining time is long. If looking into the outflow tendency of non-point pollution source at the impervious area, it showed the tendency that the concentration lowers gradually as time goes by after initial concentration appeared very high. However, it could be recognized that the concentration of non-point pollution source appeared to be high as the pollutants integrated on the surface of the road during dry season. The Event Mean Concentrations (EMCs) in impervious area were ranged $9.2{\sim}199.3mg{\cdot}L^{-1}$ for TSS, $8.1{\sim}24.2mg{\cdot}L^{-1}$ for $COD_{Mn}$, $0.070{\sim}1.860mg{\cdot}L^{-1}$ for T-N. Based on such runoff characteristics of non-point pollution source, it is judged that it would be desirable to process initial rain efficiently as the measure against initial rain phenomenon at the impervious area.

• Korean Journal of Ecology and Environment
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• v.44 no.3
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• pp.292-302
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• 2011

The Lake Sihwa watershed includes industrial, urban, and rural areas simultaneously. In this study, we analyzed the characteristics of dissolved organic matter (DOM) in spatial-temporal runoff patterns at representative sites having different land use in the watershed of Lake Sihwa. The result of synchronous and 3D-EEMs(3-Dimensional Excitation Emission Matrix Spectroscopy) analysis in 4TG (industrial area), fluorescence distribution and variation clearly appeared in the Fulvic-like fluorescence (FLF) and Humic-like fluorescence (HLF) regions along with the Protein-like fluorescence (PLF) region. A characteristic that Peak A (HLF) region fluorescence intensity did not decrease and the HLF region of fluorescence intensity and spatial-temporal changes clearly appeared during rainfall in AS (urban area). The results of fluorescence analysis in MS did not show great changes in PLF and FLF while showing that fluorescence intensity changes over time in the Terrestrial-like fluorescence (THLF) region increased greatly. In conclusion, our results showed significant differences in the runoff characteristics of DOM particularly in industrial, urban and rural area, and these differences should be considered for the efficient controlling of DOM in the watershed.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.366-367
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• 1999

오존과 같은 광화학 오염물질의 특징 중의 하나는 도시나 공업단지 등의 차량이나 공장 등으로부터 초기에 배출된 질소산화물(NO$_{x}$ :Oxides of nitrogen), 비메탄계 유기화합물(NMOC:non-methan organic carbon), 알데히드류(RCHO, HCHO 등)와 같은 1차 오염물질이 바람을 따라 풍하측으로 이동하면서 광화학반응을 일으켜 풍하측의 도시에 고농도의 오존을 발생시키는 것이다.(중략)

• Journal of Soil and Groundwater Environment
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• v.13 no.4
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• pp.54-61
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• 2008

Permeable reactive barriers (PRBs) technology has been focused in contaminated groundwater remediation. It is necessary to select adequate reactive material according to characteristics of contaminant in groundwater. In this research, the reaction between reactive material and heavy metal contaminants was estimated through column test. Reactive material was slag, which has been produced in Gwangyang power plant, and heavy metal contaminants were cadmium, lead and copper. Column test was performed in the condition of 1) single and multi contaminated solution and 2) different initial concentration of cadmium. Retardation factor of cadmium is 3.94 in multi contamination. But that of copper is 40.3 in single and 25 in multi. The difference of retardation between cadmium and copper is due to affinity, resulted from the difference of electronegativity. In multi-contamination, copper effluent concentration was above initial copper concentration and at the same time lead effluent concentration was decreased. This phenomenon was considered that lead extract copper sorbed in slag and then lead was sorbed to the vacant sorption site instead. And as the initial concentration was increased, the retardation factor of cadmium became decreased.

• Korean Journal of Ecology and Environment
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• v.56 no.2
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• pp.127-139
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• 2023

Daechung Reservoir has been suffering from severe cyanobacterial blooming periodically due to the water pollutants from the watershed, especially nutrients from nonpoint sources. As a countermeasure, an artificial wetland was constructed to mitigate the pollutant load from the watershed by utilizing the vegetation. We investigated the water quality of the influent and outflow of the wetland during years 2014~2020 to evaluate the performance of pollutant removal through the wetland. Major pollutants (e.g. BOD, COD, SS, T-N, and T-P) were largely reduced during the retention in the wetland while nutrients removal was more efficient than that of organic matters. Pollutant removal efficiency for different inflow concentrations was also investigated to estimate the wetland's capability as a way of managing nonpoint sources. The efficiency of water treatment was significantly higher when inflow concentrations were above 75^th percentile for all pollutant, implying the wetland can be applied to the pre-treatment of high pollution load including initial rainfall runoff. Furthermore, the yearly variation of removal efficiency for seven years was analyzed to better understand long-term trends in water treatment of the wetland. The annual treatment efficiency of T-P was very high in the early stages of vegetation growth with high concentration of inflow water. However, it was confirmed that the concentration of inflow water decreased, vegetation stabilized, and the treatment efficiency gradually decreased as the soil was saturated. The findings of the study suggest that artificial wetlands can be an effective method for controlling harmful algal blooms by alleviating pollutant load from the tributaries of Daechung Reservoir.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.6
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• pp.751-758
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• 2019

This study tested various assumptions that simplified the configuration of the numerical model for unsaturated zone's contaminant transport to simulate the pathway to exposed point. This study investigated the contaminant migration through in the pollutant exposure pathway of vadoze zone for risk assessment of the contaminated site. For the purpose, generic scenarios as well as contaminant-based scenarios were simulated using the numerical code for transport of the contaminant in the pathway. The finite-difference one-dimensional transport with adsorption and biodegradation were considered, and it also assumed that the initial concentration was also depleted over time. The results of the generic-scenario show that as the groundwater infiltration rate decreases, the longer the path from the source to the groundwater level, the lower the concentration at the point of inflow into the groundwater level. In particular, in the case of high biodegradation rate and rapid depletion of pollutant sources, statistically outliers were found in the simulated results and generic scenarios was good at prediction.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.5
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• pp.930-934
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• 2006

In this study, we conducted water-quality analysis of wastewater and in-situ flow measurement using automatic flow rate measuring instrument to identify characteristics of wastewater in urban areas, and collected samples in gutter fur storm water drain, rainfall bucket, and aqueduct of pipe from roof, and outfalls of basins to examine the contribution by pollution origins such as base wastewater, atmospheric washing, runoff by roof surface, runoff by road surface, erosion of sewer sediment. In the result, the concentration of pollutants reached peak in the beginning of rainfall due to first flush, was 3 to 10 times higher than average concentration of dry period, and was lower than that of dry period due to dilution of storm water. In the analysis of the contribution by pollution origins, the ratio of load by sewer sediment resuspension to the total pollution load was 54.6% fer COD, and 73.3% fur SS. Accordingly, we can reduce the total pollutant load by periodical dredging and washing of sewer sediment, and control the loadings by overflow of combined sewer overflows.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.10a
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• pp.256-257
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• 2000

해양의 생물자원 또는 수산생물에게 저해영향을 미치는 오염물질의 농도를 결정하는 수단으로서 현재 전세계적으로 가장 널리 사용되고 있는 것은 표준실내 생물검정시험(Standard Laboratory Bioassay)을 들 수 있다. ASTM(American Society for testing and Materials), OECD(Organization for Economic Cooperation and Development), USEPA(Unated States Environmental Protection Agency)와 같은 단속기관에서는 연안에 방출되는 오염물질에 대한 허용한계농도를 정하기 위하여 급성 독성 결과를 기준으로 하고 있으며, ASTM과 OECD에서는 생육초기독성 시험을, USEPA에서는 생육초기 독성시험과 만성독성을 채택하고 있다. (중략)

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.668-672
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• 2009

상대오염도가 높은 초기유출수에 대한 1차 처리의 화학적인 효율성 증대에 대한 연구는 많이 진행되어온 반면 동수역학적 분석에 관한 연구는 미흡한 실정이다. 본 연구에서는 수처리 시설에 대해서 수리모형 및 수치모의의 결과를 비교 분석하였다. 연구에 사용된 수처리 시설은 내부 격벽(baffle)의 배열에 변화를 주어 흐름제어를 유도하여 초기유출수의 처리 효율에 변화를 줄 수 있도록 시설을 고안하였다. 수리모형 및 수치모의 실험을 통해 구조물 내에 복잡한 난류흐름을 관찰하였고, 주입된 염수의 농도분포 양상을 시간변화에 따라 분석하였다. 수치모의를 위해서 3차원 수치모형 프로그램인 FLOW-3D를 사용하였으며 LES 난류모형과 질량생성(mass source)모형을 적용하여 수처리 시설 내에서의 동수역학적 거동분석 및 오염원(source)의 농도분포를 모의하였다. 실험 결과 수처리 시설의 3차원 난류흐름을 통해 오염원이 지체 및 확산되고 이에 따라 배출되는 농도가 현격하게 차이 냄을 확인하였다. 또한 추후 본 연구에서 제시된 바와 같이 다양한 내부구조에 대한 수치모의 결과를 분석하게 되면 초기 유출수 처리 효율을 증가시킬 수 있는 수처리 시설모형의 최적화 방안을 고려할 수 있을 것이다.

• Journal of Life Science
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• v.10 no.3
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• pp.247-253
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• 2000

The effects of acute of marine toxicants on early life of coastal olive flounder were investigated. An increasing order of acute toxicity on embryo- and larva-stages of Paralichtys olivaceus was CdCl2$\mu\textrm{g}$/L and 29 $\mu\textrm{g}$/L, respectively, and those values at larva-stage were estimated 3.5 ng/L, 16.0 nL/L, 10.5 $\mu\textrm{g}$/L and 15.0 $\mu\textrm{g}$/L, respectively.