• Title/Summary/Keyword: Mass first flush ratio

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Runoff Characteristics of Non-point Pollutant Sources in an Agricultural Area Watershed (농촌지역 비점오염물질의 유출 특성)

  • Ryu, Kwang-Hyun;Lee, Geon-Jik;Seong, Jin-Uk;Kim, Dong-Sup;Park, Jae-Chul
    • Korean Journal of Ecology and Environment
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    • v.44 no.2
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    • pp.178-186
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    • 2011
  • This study was conducted to investigate runoff characteristics of non-point pollutant sources in an agricultural area watershed in Boeun area, Chungbuk Province. The monitoring site represented 1.56 $km^2$, about 44.4% of which was covered with paddy fields. The monitoring was conducted for six events in a period of 5 month. Event Mean Concentration (EMC) and Site Mean Concentration (SMC) of suspended solids (SS), biochemical oxygen demand (BOD), chemical oxygen demand (COD), total nitrogen (T-N) and total phosphorus (T-P) were calculated using the results of the water quality parameters. A comparison between arithmetic mean concentration and EMC revealed that nearly all EMCs were higher than the corresponding arithmetic mean concentrations. First-flushing effects were exhibited for SS, BOD, and T-P, with relatively high concentrations in early-stage storm events.

Treatment Efficiency of Non-Point Source Pollutants Using Modified Filtration System (개선된 여과형 시설의 비점오염물질 처리효율 평가)

  • Kang, Hee-Man;Choi, Ji-Yon;Kim, Lee-Hyung;Bae, Woo-Keun
    • Journal of Wetlands Research
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    • v.13 no.2
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    • pp.161-169
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    • 2011
  • The objective of this study was to evaluate the efficiency of a modified filtration system treating non-point source (NPS) pollutants. The developed Best Management Practice (BMP) technology was designed based on the geographical and climatic characteristics of the site. A lab-scale test experiment was conducted using three different hydraulic loading rates representing the first flush flow, average flow and overflow conditions during a rainfall event. Water quality analysis was performed on the water samples taken at the inflow, outflow and infiltration during the test experiment of the lab-scale BMP. Also, the water and mass balance at different hydraulic loading rates was determined. Results from the lab-scale test experiment showed that the lab-scale BMP had a high removal efficiency of 80-90% for all NPS pollutants. The overflow test condition obtained the lowest removal efficiency among the hydraulic loading rates because it gave less opportunity for the pollutants to be filtered and retained inside system. The infiltration ratio was approximately 1 % of the inflow and outflow. Increasing the infiltration ratio requires technical approach of soil amendment where the BMP is installed.

The Estimating MFFn by SWMM in The Transportation Area (SWMM 모형을 활용한 도로 형태별 초기세척비율 산정)

  • Kwon, Hun-Gak;Lee, Jae-Woon;Yi, Youn-Jeong;Shin, Suk-Ho;Lee, Chun-Sik;Lee, Jae-Kwan
    • Journal of Environmental Science International
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    • v.21 no.3
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    • pp.277-287
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    • 2012
  • The MFFn(Mass First Flush) was analyzed for various rainy events(monitoring data from 2008 to 2009) in Transportation area(Highway, National road, Trunk road). Estimated MFFn using SWMM was evaluated by comparison with observed MFFn. MFFn was estimated by varying n-value from 10% to 90% on the rainy events. The n-value increases, MFFn is closed to '1'. As time passed, the rainfall runoff was getting similar to ratio of pollutants accumulation. The result of a measure of the strength of the linear relationship between observed data and expected data under model was good ($R^2$=0.89). Pollutants runoff loads by volume showed Highway 26.6%, National road 44.8%, Trunk road 35.0% at the MFF20(20% by total runoff). A case of MFF30, pollutants runoff loads by volume showed Highway 40.2%, National road 54.3%, Trunk road 46.8%. According to the results, Initial precipitation basis were Highway MFF30, National road MFF20, Trunk road MFF30 when the Non-Point source control facilities set up.