박지현 Ji Hyun Park , 구영훈 Young Hun Ku , 백경오 Kyong Oh Baek , 김영도 Young Do Kim

DOI:10.15681/KSWE.2015.31.1.1 Vol.31(No.1) 1-11, 2015

In this study, the attraction efficiency of the by-pass fishway installed at Dalseong Weir in Nakdong River was assessed according to operation of the attraction waterway by using River2D which is a two-dimensional physical habitat simulation model. The model was calibrated and validated through the measured water elevation. The attraction efficiency of the fishway was evaluated at the low flow condition because the target fish, Zacco platypus (Z. platypus), have moved frequently up and downstream at the spawning season from April to June. From simulation results, it can be deduced that the attraction efficiency at situation of open attraction waterway is superior to that of close attraction waterway. Also it is shown that velocity field at inner region of the fishway is suitable for migration of the fish.

Attraction efficiency, Attraction waterway, By-pass fishway, Dalseong weir, River2D

Precious Eureka D Flores , Marla C Maniquiz Redillas , Jevelyn Ann S Tobio , Lee Hyung Kim

DOI:10.15681/KSWE.2015.31.1.12 Vol.31(No.1) 12-18, 2015

In this research, the hydrologic effects between a pre-existing urban landuse and low impact development (LID) applied conditions were compared and evaluated. The infiltration trench and tree box filter that were utilized in LID represent only 1% of the catchment area that they drain. Storm event monitoring were conducted from July 2010 to July 2014 on a total of 22 storm events in both LID sites. After LID, hydrological improvement was observed as the sites exhibited a delay (lag time) or reduction in the magnitude, frequency and duration of runoff and flow peaks as the rainfall progress. In addition, the maximum irreducible peak flow reduction for infiltration trench was found to be 61% and 33% for the tree box filter when rainfall was 40 mm and 30 mm, respectively. In designing LID, it is recommended to consider the storage capacity and catchment area, as well as the amount of rainfall and runoff on the site.

Hydrologic effect, Low impact development, Peak flow, Rainfall, Runoff

곽재원 Jae Won Kwak , 한희찬 Hee Chan Han , 이민정 Min Jung Lee , 김형수 Hung Soo Kim , 문장원 Jang Won Mun

DOI:10.15681/KSWE.2015.31.1.19 Vol.31(No.1) 19-28, 2015

The purpose of this research is reconstruction of annual precipitation based on Tree-ring series at Seorak mountain and examine its effectiveness. To do so we performed nonlinear time series characteristics test of Tree-ring series and reconstructed annual precipitation of Gangneung from 1687 to 1911 using Artificial neural network and Nonlinear autoregressive exogeneous input (NARX) model which reflects stochastic properties. As a result, Tree-ring series at Seorak Mountain shows nonlinear time series property and reconstructed annual precipitation series drawn from NARX is similar in statistical characteristics of observed annual time series.

Annual precipitation, NARX, Neural network, Tree-ring

최익원 Ik Won Choi , 김재훈 Jae Hoon Kim , 임종권 Jong Kwon Im , 박태진 Tae Jin Park , 김세영 Se Young Kim , 손대희 Dae Hee Son , 허인애 In Ae Huh , 류덕희 Doug Hee Rhew , 유순주 Soon Ju Yu

DOI:10.15681/KSWE.2015.31.1.29 Vol.31(No.1) 29-34, 2015

The aim of this study is to understand the limitation of organic pollutant indexes (BOD5, CODMn, CODCr) and estimate to set the TOC standard by comparing oxidation rates of BOD5, CODMn, CODCr and TOC based on the 487 organic compounds and 11 effluents from industrial wastewater containing various and unknown organic compounds. The range of ratio of theoretical oxygen demand (ThOD) to theoretical organic carbon (TOCt) was 0.00~5.33 and average ratio of classes of organic compounds was 2.68~3.70. According to classes of organic compounds, the average ratio of O2/C was 1.2 (range : 1.02~1.39). The order of oxidation rate for 15 organic compounds was TOC (90.7%) > CODCr (88.8%) > BOD5 (54.4%) > CODMn (30.8%) indicating the lower oxidation rate of BOD5 and COD compared with TOC. The ranking for average oxidation rate was CODCr > CODMn > BOD5 indicating that BOD5, CODMn could be underestimated comparing with ThOD of organic compounds in case of industrial wastewater containing high concentration of refractory organic compounds. Most of the relationships between organic pollutant indexes and TOC were higher than 0.9. The ratio of TOC to organic compound indexes decreased in the order : CODCr (3.4) > CODMn (1.9) > BOD5 (0.7).

BOD5, COD, Industrial wastewater, ThOD, TOC

백경오 Kyong Oh Baek , 김창환 Chang Hwan Kim

DOI:10.15681/KSWE.2015.31.1.35 Vol.31(No.1) 35-41, 2015

This study focuses on whether a physical habitat model, River2D, is useful to assess and design stream restoration. To achieve the aim, the habitat suitability for Zacco Platypus was analyzed using River2D at midstream of the Anyang-Cheon through modifying the low flow channel and changing the flow discharge. The River2D simulation results show that the inhabited environment for Zacco Platypus is improved by increasing the sinuosity of the low flow channel, and vice versa. Also the inhabited environment for Zacco Platypus gets worse when there is no additional flow for maintenance water supply at the stream flowing through cities. In this respect, the physical habitat simulation study based on the River2D model is useful because it provides a practical guidance in designing stream restoration.

Maintenance discharge, Physical habitat model, Sinuosity, Stream restoration

이규영 Gyu Young Lee , 김정철 Jung Chul Kim , 임지현 Ji Hyun Lim , 이준우 Jun Woo Lee , 박정미 Jeong Mi Park , 이승훈 Seung Hun Lee , 남주경 Ju Kyung Nam , 이용우 Yong Woo Lee

DOI:10.15681/KSWE.2015.31.1.42 Vol.31(No.1) 42-48, 2015

This study focused on effective decomposition methods for low concentrated organic compounds from the reuse of industrial wastewater, and confirmed the possibility through photocatalyst media. Photocatalyst immobilized media was developed to carry on this experiment which confirmed the removal possibility of low concentrated organic compounds. Considering the stability and efficiency of photocatalyst immobilization, inorganic support, hollow bead, and TiO2 nano powder were used. As a result of the removal experiment, the removal efficiencies of acetonitrile, ethanol, IPA(Isopropyl alcohol), methanol were above 75% after 15 minutes while those of acetone, acetaldehyde, urea were 10%, 45%, 20%, respectively after 60 minutes. If further studies were made to increase the surface area of the photocatalyst immobilized media, the efficiency of the removal of low concentrated organic compounds can be improved and this solution can also be used in an actual treatment process.

Low concentrated organics, Media, Photocatalyst, Wastewater reuse

신기식 Ki Sik Shin , 박우상 Woo Sang Park , 이정서 Jung Seo Lee , 유순주 Soon Ju Yu , 박태진 Tae Jin Park , 김종민 Jong Min Kim

DOI:10.15681/KSWE.2015.31.1.49 Vol.31(No.1) 49-54, 2015

Acute toxicity test with Daphnia magna has a variety of factors such as incubation condition of test species, food quality and proficiency of laboratory workers. Therefore, proper proficiency testing samples were required for evaluating the competence of laboratory workers. This study aims to propose some appropriate proficiency testing samples for laboratory workers of acute toxicity test with Daphnia magna. Proposed four kinds of standard samples (Sample A, B, C, and D) for proficiency testing were selected from reference materials which were recommended from Canada and USA WET(Whole Effluent Toxicity) authorities. Proposed standard samples were tested by trial application of proficiency testing, homogeneity and stability checks using repeatability test. Sample A, C and D were estimated ad the suitable candidates for proficiency test standard samples except for Sample B. In addition, Sample A was proved to be the most suitable sample.

Acute toxicity, Daphnia magna, Proficiency testing, Reference materials

최윤호 Youn Ho Choi , 금동혁 Dong Huyk Kum , 류지철 Ji Chul Ryu , 정영훈 Young Hun Jung , 김용석 Yong Seok Kim , 전지홍 Ji Hong Jeon , 김기성 Ki Sung Kim , 임경재 Kyoung Jae Lim

DOI:10.15681/KSWE.2015.31.1.55 Vol.31(No.1) 55-66, 2015

It has been well known that it is not easy to quantify pollutant loads driven by non-point source pollution due to various factors affecting generation and transport mechanism of it. Especially pollutant loads through baseflow have been investigated by limited number of researchers. Thus in this study, the Web-based WAPLE (WHAT-Pollutant Load Estimation) system was developed and applied at study watersheds to quantify baseflow contribution of pollutant. In YbB watershed, baseflow contribution with WWTP discharge is responsible for 49.5% of total pollutant loads at the watershed. Among these, pollutant loads through baseflow (excluding any WWTP discharge) is responsible for 61.7% of it. In GbA watershed, it was found that 58.4% is contributed by baseflow with WWTP discharge 2.9% and 97.1% is by baseflow. For NbB watershed (without WWTP discharge), 52.3% of pollutant load is transported through baseflow. As shown in this study, it was found that over 50.0% of TN (Total Nitrogen) pollutant loads are contributed by non-direct runoff. Thus pollutant loads contributed by baseflow and WWTP discharge as well as direct runoff contribution should be quantified to develop and implement watershed-specific Best Management Practices during dry period.

Baseflow, Non-Point Source, TN (Total Nitrogen) Pollutant Loads, WAPLE

김홍태 Hong Tae Kim , 신동석 Dong Seok Shin , 김용석 Yong Seok Kim

DOI:10.15681/KSWE.2015.31.1.67 Vol.31(No.1) 67-70, 2015

Some data into combined and sanitary sewer system were collected in order to find out the characteristics of discharge from first flush rainfall inflow. The inflow ratios of combined and sanitary sewer system were 0.46 and 0.27 during rains from various survey data. The average inflow ratio 0.31 was appropriate for general application because many watersheds were not classified clearly as combined or sanitary sewage treatment areas. The percentage of first flush loads in the whole BOD load was about 10%. This result was thought some meaningful, comparing with similarity of first flush pollution load contribution previous surveyed by KECO (2004).

Combined sever overflow, First flush, Inflow ratio, Pollution loads