• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.2008-2012
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• 2007

통계청 등의 기관에 구축되어있는 기본적인 비점오염원 자료들은 행정구역별로 나뉘어져 있지만 실제수계에 도달하는 부하량 산정을 위해서는 유역별로 구분을 다시 해야만 하는 번거로움이 있다. 따라서 본 연구에서는 반복되는 비점오염원 자료의 전처리 과정의 번거로움을 피하기 위하여 지리정보체계(Geographical Infomation System; GIS)와 VBA(Visual Basic for Application)를 이용하여 통계자료의 전처리 과정을 한 번에 처리할 수 있는 시스템을 구축하였다. 본 시스템은 선택한 유역도와 행정구역도를 중첩하여 유역 내 최소행정구역의 점유율을 반영한 통계자료를 사용자 친화적으로 재분류하는 시스템이다. 본 시스템의 적용성 확인을 위하여 새만금유역 내 주상천유역을 대상으로 연구를 실시하였으며, 새만금유역에 포함되는 전라북도 최소행정구역의 토지이용 통계자료만을 기본 데이터로 활용하였다. 본 연구에서 구축된 시스템은 오염부하량 산정에 있어 요구되는 기본적인 데이터를 얻는 것에 있어서 기존의 장시간에 걸친 단순 반복작업을 대신하는 효율적인 시스템이며, ArcGIS에 대한 이해가 부족한 사용자의 경우에도 간단한 시스템조작만으로도 필요한 데이터를 구축할 수 있어 사용자에게 편리함을 제공한다. 향후 본 시스템을 이용하여 비점오염부하량 산정시스템을 개발할 수 있고, 기상자료 등과 같은 수문모형으로의 적용도 가능할 것으로 기대된다.

• Journal of The Korean Society of Agricultural Engineers
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• v.49 no.1
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• pp.89-97
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• 2007

Simple regression models for pollutants load estimation of paddy developed by the Ministry of Environment in 1995 were tested with the data (T-N, T-P, $COD_{Mn}$, and SS) collected from Yeongsan and Seomjin river watersheds, and improvement measures were suggested. Overall, the simulated values showed a great difference from the measured values except for T-P according to the statistical analyses (RMSE, root mean square error; RMAE, root mean absolute error; RB, relative bias; EI, efficiency index). Such difference was assumed due to the fact that the models use only hydrologic factors (quantity factor) associated with precipitation and run-off as input parameters, but do not consider other factors which are likely to affect pollutant concentration (quality factor) including days after fertilization. In addition, in terms of accessibility of the models, some parameters in the models such as run-off depth and run-off amount which can not be obtained from the weather database but should be collected by on-site measurements need to be replaced with other variables.

• Water Engineering Research
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• v.4 no.1
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• pp.19-30
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• 2003

TMDL development and implementation have great potential fur use in efforts to improve water quality management, but the TMDL approach still has several difficulties to overcome in terms of cost, time requirements, and suitable methodologies. A well-defined prioritization approach for identifying watersheds of concern among several tar-get locations that would benefit from TMDL development and implementation, based on a simple screening approach, could be a major step in solving some of these difficulties. Therefore, a web-based decision support system (DSS) was developed to help identify areas within watersheds that might be priority areas for TMDL development. The DSS includes a graphical user interface based on the HTML protocol, hydrological models, databases, and geographic information system (GIS) capabilities. The DSS has a hydrological model that can estimate non-point source pollution loading based on over 30 years of daily direct runoff using the curve number method and pollutant event mean concentration data. The DSS provides comprehensive output analysis tools using charts and tables, and also provides probability analysis and best management practice cost estimation. In conclusion, the DSS is a simple, affordable tool for the preliminary study of TMDL development via the Internet, and the DSS web site can also be used as an information web server for education related to TMDL.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.929-936
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• 2011

To treat non-point source pollution in Dongbok lake, removal efficiencies of pollutants were investigated in Dongbokcheon constructed wetlands (CWs) at different treatment time and wastewater loading. The wetlands consisted of forebay, wetlands ($1^{st}$, $2^{nd}$, $3^{rd}$, $4^{th}$, $5^{th}$, $6^{th}$, $7^{th}$, and $8^{th}$ wetlands) and sedimentation pond. The concentrations of BOD, SS, T-N, and T-P in inflow ranged $0.85{\sim}3.14mg\;L^{-1}$, $3.33{\sim}9.70mg\;L^{-1}$, $0.64{\sim}5.33mg\;L^{-1}$, and $0.03{\sim}0.10mg\;L^{-1}$ from April to October in 2008, respectively. The removal rates of BOD, SS, T-N, and T-P in Dongbokcheon CWs were 34%, 5%, 31%, and 13%, respectively. The removal rates of BOD and T-N were higher than those for SS and T-P. The amounts of pollutant removal in Dongbokcheon CWs were higher in the order of forebay > wetlands > sedimentation pond for BOD, sedimentation pond > wetlands > forebay for SS, sedimentation pond > forebay > wetlands for T-N. The amount of T-P removal in wetlands was higher than forebay and sedimentation pond.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.6
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• pp.373-381
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• 2012

An automatic flow and water quality monitoring system was applied to estimate pollutant loads to an urban stream during storm events in DTV (Daeduk Techno Valley), Daejeon, Korea. The monitoring system consists of rainfall gage, ultrasonic water level meter, water quality sensors for DO, temperature, pH, conductivity, turbidity and automatic water sampler for further laboratory analysis. All data are transmitted through on-line system and the monitoring system is designed to be controlled manually in the field and remotely from laboratory computer. Flow rates were verified with field measurements during storm events and showed good agreements. Automatic sampler was used to collect real time samples and analyzed for BOD, COD, TN, TP, SS and other pollutant concentrations in the laboratory. SWMM (Storm Water Management Model) urban watershed model was applied and calibrated using the observed flow and water quality data for the study area. While flow modeling results showed good agreement for all events, water quality modeling results showed variable levels of agreement. These results indicate that current options in the SWMM model to predict pollutant build up and wash-off effects are not sufficient to satisfy modeling of all the rainfall events under study and thus need further modification. This study showed the automatic monitoring system can be used to provide data to assist further refinement of modeling accuracy. This automatic stormwater monitoring and modeling system can be used to develop basin scale water quality management strategies of urban streams in storm events.

• Journal of Wetlands Research
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• v.15 no.3
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• pp.407-412
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• 2013

The aim of this study was to develop a tree box filter system, an example of Low Impact Development technology, for treating stormwater runoff from road. Monitoring of storm events was performed between June 2011 and November 2012 to evaluate the system performance during wet day. Based on the results, all runoff volume generated by rainfall less than 2 mm was stored in the system. The minimum volume reduction of 20% was observed in the system for rainfall greater than 20 mm. The greatest removal efficiency was exhibited by the system for total heavy metals ranging from 70 to 73% while satisfactory removal efficiency was exhibited by the system for particulate matters, organic matters and nutrients ranging from 60 to 68%. The system showed greater pollutant removal efficiency of 67 to 83% for rainfall less than 10 mm compared to rainfall greater than 10 mm which has 39 to 75% pollutant removal efficiency. The system exhibited less pollutant reduction for rainfall greater than 10 mm due to the decreased retention capacity of the system for increased rainfall. Overall, the system has proved to be an option for stormwater management that can be recommended for on-site application. Similar system may be designed based on several factors such as rainfall depth, facility size and pollutant removal efficiency.

• Ecology and Resilient Infrastructure
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• v.3 no.4
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• pp.247-255
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• 2016

Non-point pollutants from surface runoff during rainfall exert adverse effects on urban river water quality management. In particular, the first flush effect during the initial phase of rainfall can deliver significant amounts of pollutant loads to surface waters with extremely high concentrations. In this study, a sustainable first flush effect management system was developed by using settling and filtration that require no additional power or chemicals. A pilot scale experiment has shown that the removal of total suspended solid (TSS), total nitrogen (TN) and total phosphorus (TP) are in ranges of 84 - 95%, 31 - 46%, and 42 - 86%, respectively. An Integrated Stormwater Runoff Management System (ISTORMS) was also developed to efficiently manage the developed system by linking weather forecast, flow rate and water quality modeling of surface runoff and automatic monitoring systems in fields and in the system. This study can provide effective solutions for the management of urban river in terms of both quantity and quality.

• Journal of the Society of Disaster Information
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• v.9 no.2
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• pp.145-152
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• 2013

This study was conducted to improve the Nonpoint-source pollutant treatment plant efficiency and maintenance. Field and laboratory permeability test were conducted three times each before and after displacement. The removal efficiency such as TSS, BOD, CODmn, T-N, and T-P were investigated from the year of 2006 to 2011. The coefficient of permeability right after displacement was calculated to be $1.07{\times}10^{-3}(cm/s)$, coefficient of permeability after a year was calculated to be $0.88{\times}10^{-3}(cm/s)$, and after five years, it was calculated to be $0.3{\times}10^{-3}(cm/s)$ and accordingly, the amount of infiltration decreased. In case of the removal efficiency, it generally tended to decrease, but it showed the higher rates than the expected rates BOD 40%, SS 76%, T-N 39% and T-P 53%. It is concluded that displacement cycle should be at least five years and that dredging cycle should be at least three months and at most one year.

• Journal of Environmental Impact Assessment
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• v.24 no.1
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• pp.16-34
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• 2015

Impervious covers(IC) are artificial structures, such as driveways, sidewalks, building's roofs, and parking lots, through which water cannot infiltrate into the soil. IC is an environmental concern because the pavement materials seal the soil surface, decreasing rainwater infiltration and natural groundwater recharge, and consequently disturb the hydrological cycle in a watershed. Increase of IC in a watershed can cause more frequent flooding, higher flood peaks, groundwater drawdown, dry river, and decline of water quality and ecosystem health. There has been an increased public interest in the institutional adoption of LID(Low Impact Development) and GI(Green Infrastructure) techniques to address the adverse impact of IC. The objectives of this study were to construct the modeling site for a samll urban watershed with the Storm Water Management Model(SWMM), and to evaluate the effect of various LID techniques on the control of rainfall runoff processes and non-point pollutant load. The model was calibrated and validated using the field data collected during two flood events on July 17 and August 11, 2009, respectively, and applied to a complex area, where is consist of apartments, school, roads, park, etc. The LID techniques applied to the impervious area were decentralized rainwater management measures such as pervious cover and green roof. The results showed that the increase of perviousness land cover through LID applications decreases the runoff volume and pollutants loading during flood events. In particular, applications of pervious pavement for parking lots and sidewalk, green roof, and their combinations reduced the total volume of runoff by 15~61 % and non-point pollutant loads by TSS 22~72 %, BOD 23~71 %, COD 22~71 %, TN 15~79 %, TP 9~64 % in the study site.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.5
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• pp.557-564
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• 2009

A combined sewer system can quickly drain both storm water and sewage, improve the living environment and resolve flood measures. A combined sewer system is much superior to separate sewer system in reduction of the non-point source pollutant load. However, during rainfall. it is impossible in time, space and economic terms to cope with the entire volume of storm water. A sewage system that exceeds the capacity of the sewer facilities drain into the river mixed with storm-water. In addition, high concentration of CSOs by first-flush increase pollution load and reduce treatment efficiency in sewage treatment plant. The aim of this study was to develope a processing unit for the removal of high CSOs concentrations in relation to water quality during rainfall events in a combined sewer. The most suitable operational design for processing facilities under various conditions was also determined. With a designed discharge of 19.89 m/min, the removal efficiency was good, without excessive overflow, but it was less effective in relation to underflow, and decreased with decreasing particle size and specific gravity. It was necessary to lessen radius of vortex separator for increasing inlet velocity in optimum range for efficient performance, and removal efficiency was considered to high because of rotation increases through enlargement of comparing height of vortex separator in diameter. By distribution of influent particle size, the actual turbulent flow and experimental results was a little different from the theoretical removal efficiency due to turbulent effect in device.