우민희 Min Hui Woo , 이규영 Gyu Young Lee , 김지혜 Ji Hye Kim , 임지현 Ji Hyun Lim , 이용우 Yong Woo Lee

DOI: Vol.28(No.2) 171-177, 2012

This research investigates how using algae as an ecotoxicological test species is easier than using daphnia for identifying toxic causative substances. From the results of the ecotoxicity measurements on the Shihwa lake and its tributaries, heavy metals were considered as one of major factors in causing toxicity. The algae ecotoxicity value was 9.6 while the daphnia ecotoxicity value was 0.8 in the Jeongwang stream. By using algae as the test species, we could identify the toxicity that causes heavy metals which might otherwise have been missed with only daphnia. The results from the EDTA addition test showed that zinc and copper were the main toxic causative substances in the Jeongwang stream and Gunja stream.

Algae, Ecotoxicity, Heavy metal, Toxicity identification evaluation

장창원 Chang Won Jang , 김동환 Dong Hwan Kim , 이재용 Jae Yong Lee , 김연주 Yeon Ju Kim , 정성민 Sung Min Jung , 신창민 Chang Min Shin , 김범철 Bom Chul Kim

DOI: Vol.28(No.2) 178-184, 2012

BOD decay rate is a key parameter of BOD-DO models in streams and lakes. In the calibration of water quality modeling appropriate range of coefficient is required for guidance of parameter selection. In this study BOD decay rate was measured at 48 stream sites and 10 reservoir sites in 8 different river systems. The decay rate ranged from 0.09 to 0.25 day-1 with a mean of 0.16 day-1. Among river systems the decay rates showed significantly different ranges, with the Han River system showing higher values than other river systems. In comparing different types of water bodies, the decay rate was slightly higher in tributaries than in reservoirs and mainstreams. Our results can provide guidance to the selection of proper coefficient for various water bodies in the calibration of water quality models.

BOD decay rate, BOD decomposition rate, Deoxygenation rate, Model coefficient

최명재 Myung Jae Choi , 박혜경 Hae Kyung Park , 윤석환 Seuk Hwan Yun , 이장호 Jang Ho Lee

DOI: Vol.28(No.2) 185-196, 2012

The fish community within the lake and 5 tributaries of Lake Chungju in spring and autumn, 2009 was surveyed. In this study, the total 128,506 individuals were collected belonging to 11 families 29 genera 34 species. The most dominant species was Squalidus japonicus coreanus that account for 91.6% of population and 49% of biomass of fish community. In the point of population, dominant species were small-sized species, which became the prey of big-sized predatory species. In the point of biomass, dominant species were predatory species which were large-sized. The most dominant species in lacustrine area was S. japonicus coreanus which accounted for 92.2% of total population and 49.1% of total biomass. The most dominant species of tributary streams was Tridentiger brevispinis which accounted for 66.4% of total population and 55.1% of total biomass. The site of C3 in lacustrine area and Dongdal-cheon in tributary streams collected the most number of species. Through ecological health evaluation of five tributary streams using 8 metric index of biological integrity (IBI) model, two streams (Dongdal-cheon, Kwang-cheon were evaluated as, "B", "good" condition, and Jangsung-cheon obtained grade C indicating "Fair" condition, Jecheon-cheon obtained grade D indicating "Poor" condition based on IBI model. Lepomis macrochirus which was designated as a domestic ecosystem-disturbing alien species with wide food niche have shown tendency to increase the number of individuals since 1991 indicating the adverse effect on not only fish community but also aquatic ecosystem food web of Lake Chungju.

Fish community, Index of biological integrity, Lake Chungju, Lepomis macrochirus

민경철 Kyung Chul Min , 이승목 Seung Mok Lee , 김근한 Keun Han Kim , 이희용 Hee Yong Lee , 양재규 Jae Kyu Yang , 박연종 Youn Jong Park

DOI: Vol.28(No.2) 197-201, 2012

The objective of this study was to evaluate the removal efficiency of arsenite and arsenate using composite adsorbents with various mixing ratio of recycled aluminum oxides and TiO2. From batch adsorption experiments, while the removal of As(III) was almost same with 4 different composite samples in the entire pH range, the removal of As(V) was substantially increased as the weight ratio of TiO2 in composite samples reduced and showed anionic adsorption characteristics. Both adsorption of As (III) and As(V) on composite samples followed pseudo-second-order adsorption equation and C-3 showed faster reaction rate for the removal of arsenic. From the adsorption isotherm experiments, Langmuir isotherm explained well and the maximum adsorption capacities of arsenic were obtained with C-1.

Adsorption, Aluminum oxides, Arsenic, Composite adsorbent, TiO2

김재희 Jae Hee Kim , 유광태 Kwang Tae Yoo , 전환돈 Hwan Tae Yoo , 장재선 Jae Sun Jang

DOI: Vol.28(No.2) 202-212, 2012

Due to the deterioration of water supply network and the deficiency of raw water, the water utility of local governments have performed various projects to improve their revenue water ratio. However, it is very difficult to estimate the cost for maintaining the revenue water ratio at higher level after completing the project, because local governments have different conditions affecting the operating and maintenance cost of water supply network. The purpose of this study is to present a procedure to estimate the operating and maintenance cost required to maintain the target revenue water ratio of the water supply network. For this purpose, we estimated the cost used only for operation and maintenance of water supply network of 164 local governments with the aid of K-Mean Clustering Analysis and the data from 40 representative local governments. Then, the regression analysis was performed to find relationship between revenue water ratio and the operating and maintenance cost with two different data sets generated by two classification methods; the first method classifies the local governments by means of k-means clustering, and the other classifies the local governments according to the index standardized by the operating and maintenance cost per unit length of water mains per revenue water ratio. The results shows that the method based on the index standardized by the cost and revenue water ratio of each government produces more reliable results for finding regression equations between revenue water ratio and the operating and maintenance cost only for water supply network. The estimated regression equations for each group can be used to estimate the cost required to keep the target revenue water ratio of the local government.

Cluster analysis, Operating and maintenance cost, Revenue water ratio, Water supply network

이새로미 Saeromi Lee , 이재용 Jae Yong Lee , 최재석 Jae Seok Choi , 김선정 Sun Jung Kim , 안부영 Bu Young Ahn , 김범철 Bom Chul Kim

DOI: Vol.28(No.2) 213-218, 2012

Abnormal dissolved oxygen concentration in aquatic habitat, both depletion and supersaturation, can be stress factor to aquatic animals. In this study the nationwide distribution of oxygen supersaturation was analyzed for three categories of streams (43 urban streams, 15 rural streams, and 14 forest streams) by using monitoring network data of the Korean Ministry of Environment. From the distribution analysis 30% of urban streams showed hyperoxic condition of eutrophic level, while no forest stream showed hyperoxic condition. The physiological effect of hyperoxia on fish was examined using two species of fish Zacco koreanus, which resulted in higher concentration of a stress hormone (cortisol) in fish exposed to hyperoxic concentration (196%) of oxygen. This study shows that hyperoxic condition is ubiquitous in urban and rural Korean streams, and it can be a stress factor to aquatic animals.

Cortisol, DO supersaturation, Hyperoxia, Stress factor

조은주 Eun Ju Cho , 나승민 Seung Min Na , 이세반 Se Ban Lee , 김지형 Jee Hyeong Khim

DOI: Vol.28(No.2) 219-223, 2012

The fixed solid catalysts such as glass bead, steel mesh, and TiO2 coated ceramic bead were used to investigate effect of radical production at different frequencies. The radical production rate at 300 kHz was faster than that at 35 kHz without solid, but the tendency was changed with the presence of glass bead. The presence of glass beads create non-continuous points between the solid and liquid phases leading to increased formation of cavitation bubbles. However, the radical production decreased when steel mesh was used at 35 kHz although the surface area of contact with liquid was same when glass bead was used. Hence the solid catalyst did not always enhance the radical production. The radical production using TiO2 coated ceramic bead was dramatically increased at 35 kHz due to the breakage of TiO2 coated ceramic bead. Therefore the radical productions at 300 kHz using fixed solid catalysts generally increased while at 35 kHz the results fluctuated according to the experimental conditions.

Coated TiO2, Glass bead, Radical production, Sonocatalyst, Steel mesh

박준대 Jun Dae Park , 오승영 Seung Young Oh , 최윤호 Yun Ho Choi

DOI: Vol.28(No.2) 224-231, 2012

It is necessary to develop flow duration curve (FDC) on each unit watershed in order to analyze flow conditions in the stream for the management of Total Maximum Daily Loads (TMDLs). This study investigated a simple method to develop FDC for the general use of the curve. A simple equation for daily flow estimation was derived from the regression analysis between the 8-day interval flow data of a unit watershed and the daily flow monitoring data of an adjacent upstream region. FDC can be prepared with the calculation of daily flow by the equation for each unit watershed. An annual and a full-period FDC were drawn for each unit watershed in Guem river basin. Standard flow such as low and ordinary flow can be obtained from the annual FDC. Major percentile of flow such as 10, 25, 50, 75 or 90% can be obtained from the full-period FDC. It is considered that this simple method of developing FDC can be utilized more widely for the calculation of standard flow and the assessment of water quality in the process of TMDLs.

Daily flow estimation, Daily flow monitoring data, Flow duration curve, Regression analysis, Total Maximum Daily Loads, 8-day interval flow data

엄재성 Jae Sung Eum , 장성민 Sung Min Jung , 최영순 Yong Soon Choi , 이형진 Hyung Jin Lee , 최중대 Joong Dae Choi , 김범철 Bom Chul Kim

DOI: Vol.28(No.2) 232-237, 2012

Total suspended solids (TSS), settleable suspended solids (SSS) and nonsettleable suspended solids (NSSS) were compared in streams and lakes during rain events. Samples were collected in Lake Soyang and nine agricultural streams during storm events over two years. To measure NSSS, samples were settled in 1 L cylinders for one hour and then 50% of the total sample volume was taken from the center of the cylinder. The SSS/TSS ratio in streams (0.50) was higher than in Lake Soyang (0.20). The ratio of TSS to turbidity decreased from 1.21 in the inflowing river to 0.69 in the reservoir outlet. Turbidity and NSSS showed higher correlation (r2=0.82) compared with the correlation between turbidity and TSS (r2=0.66). Median particle size decreased from 11.4 μm in the inflowing river to 4.2 μm in the lake outlet. The results indicate that only fine particles of less than 5~10 μm can be transported downstream of the lake. Because fast-flowing water in streams includes not only fine particles but also coarse particles, an overestimation of suspended sediment concentration results if only TSS is measured. Consequently, TSS and NSSS should be measured separately to evaluate the effect of suspend sediment loadings of turbid streams on aquatic habitat during the monsoon season.

Nonsettleable suspended sediment, Settleable suspended sediment, Total suspended solids, Turbidity

정승현 Seung Hyun Joung , 박혜경 Hae Kyung Park , 윤석환 Seok Hwan Yun

DOI: Vol.28(No.2) 238-246, 2012

Organic matters budget in Lake Hoengseong were monthly investigated from April 2009 to November 2009. The intense rainfall occurred at between July and August and the hydrological factors were highly varied during the rainfall season. By the concentrated rainfall, the elevation, influx and efflux were sharply increased and the turbid water was also flowed into the middle water column in Lake. The inflow of turbid water increased the nutrient concentrations in water body and this appears to stimulate of phytoplankton regard as the primary productivity of influx of organic matter. Monthly average concentration of dissolved organic carbon (DOC) was generally higher than the particulate organic carbon (POC) concentration in Lake, but Temporal and spatial variation of POC concentration was higher than DOC and the maximum POC concentration was recorded in surface water in August, had the highest phytoplankton biomass. Organic carbon concentration in inflow site was rarely changed during the dry season, but the concentration was rapidly increased by the initial intense rainfall. In organic matters budget, the most of the organic matters was inflowed from the inflow site at rainfall season. Especially, the influx of allochthonous organic matters during the intense rainfall was 72.4% in the total influx organic matters.

Allochthonous, Dissolved organic carbon, Nutrient, Organic matter budget, Particulate organic carbon, Rainfall

강현우 Hyun Woo Kang , 류지철 Ji Chul Ryu , 강형식 Hyung Sik Kang , 최재완 Jae Wan Choi , 문종필 Jong Pil Moon , 최중대 Joong Dae Choi , 임경재 Kyoung Jae Lim

DOI: Vol.28(No.2) 247-254, 2012

Soil and Water Assessment Tool (SWAT) model has been widely used in estimation of flow and water quality at various watersheds worldwide, and it has an auto-calibration tool that could calibrate the flow and water quality data automatically from thousands of simulations. However, only continuous measured day flow/water quality data could be used in the current SWAT auto-calibration tool. Therefore, 8-day interval flow and water quality data measured nationwide by Korean Ministry of Environment (MOE) could not be used in SWAT auto-calibration even though long-term flow and water quality data in the Korean Total Maximum Daily Load (TMDL) watersheds available. In this study, current SWAT auto-calibration was modified to calibrate flow and water quality using 8-day interval flow and water quality data. As a result of this study, the Nash and Sutcliffe Efficiency (NSE) values for flow estimation using auto-calibration are 0.77 (calibration period) and 0.68 (validation period), and NSE value for water quality (T-P load) estimation (using the 8-day interval water quality data) is 0.80. The enhanced SWAT auto-calibration could be used in the estimation of continuous flow and water quality data at the outlet of TMDL watersheds and ungaged point of watersheds. In the next study, the enhanced SWAT auto-calibration will be integrated with Web based Load Duration Curve (LDC) system, and it could be suggested as methods of appraisal of TMDL in South Korea.

Auto-calibration, Pollutant Load, SWAT model, 8-day interval flow, water quality data

정성민 Sung Min Jung , 엄재성 Jae Sung Eum , 장창원 Chang Won Jang , 최영순 Young Soon Choi , 김범철 Bom Chul Kim

DOI: Vol.28(No.2) 255-268, 2012

Nonpoint source pollution has become a concern for water quality in the Han River system, especially during the high runoff events during the monsoon season. The patterns in nonpoint source runoff the relationships with land use, rainfall intensity, and stream nutrients concentrations were surveyed in 19 streams in the Han River watershed. The results show that the magnitude of NPS inputs of nutrients and sediment in the Han River watershed are of a serious concern. In the South Han River watershed, event mean concentrations (EMC) for biochemical oxygen demand (BOD), suspended sediment (SS), dissolved organic carbon (DOC), dissolved total phosphorus (DTP), total nitrogen (TN) Nitrate (NO3-N) and total phosphorus (TP) were 1.94 mg·L-1, 251mg·L-1, 2.75mg·L-1, 0.076mg·L-1, 2.82mg·L-1, 2.40mg·L-1 and 0.232mg·L-1, respectively. In the North Han River watershed, EMCs for BOD, SS, DOC, DTP, TN, NO3-N and TP were 1.34 mg·L-1, 172 mg·L-1, 2.63 mg·L-1, 0.032 mg·L-1, 1.97 mg·L-1, 1.55 mg·L-1 and 0.148 mg·L-1, respectively. The specific export coefficients of nutrient and sediments were much higher than those of other reports. Our study also found that the proportion of agricultural field area was significantly correlated with the EMCs for nutrients. Therefore, efforts to reduce NPS loading must focus on agricultural practices in the watershed. The relationships between land use and nutrient and sediment export found in this study can be used to derive estimates of runoff coefficients for agricultural field and as input data for modeling works and to develop total maximum daily load and best management practices in the Han River watershed.

Agriculture, Event mean concentrations, EMCs, Nonpoint pollutant, Specific export Loading, Total rainfall

이태섭 Tae Seop Lee , 김영진 Young Jin Kim , 함상우 Sang Woo Ham , 홍승관 Seung Kwan Hong , 박병주 Byung Joo Park , 신용일 Yong Il Shin , 정인식 In Sik Jung

DOI: Vol.28(No.2) 269-276, 2012

The surface characteristics and performance of PTFE (polytetrafluoroethylene) hollow fiber membranes have been systematically investigated at lab- and pilot-scale to assess their application to membrane-bioreactor, particularly for integrating wastewater reclamation and rainwater harvesting. The PTFE membrane expressed some surface features, such as hydrophobicity, which might enhance membrane fouling. However, lab-scale performance and cleaning experiments under various conditions demonstrated that the PTFE membrane could produce the desirable water flux with good cleaning efficiency, implying easy operation and maintenance due to superior chemical resistance of PTFE membranes. Most of effluent water qualities were met with Korean standard for discharge and reuse, except color. Color level was further reduced by blending with rainwater at 75:25 ratio. Based on the lab-scale experimental results, the pilot plant was designed and operated. Pilot operation clearly showed sTable performance with satisfactory water quality, suggesting that PTFE membrane could be applied for decentralized MBR integrated with rainwater use.

Color removal, Membrane bio-reactor, Polytetrafluoroethylene, PTFE, hollow fiber membrane, Rainwater harvesting, Wastewater reclamation

김동희 Dong Hee Kim , 임수빈 Soo Bin Yim

DOI: Vol.28(No.2) 277-284, 2012

This study developed a new ceramics in which natural zeolite was mixed and calcined with industrial by-product such as converter slag, red mud, and fly ash and evaluated the feasibility of the ceramics for removal of heavy metals in acid wastewater. The removal rate of heavy metal by ceramics increased in the order of ZS (zeolite and slag) > ZR (zeolite and red mud) > ZF (zeolite and fly ash) ceramics. The alkalinity increment and coherence of ceramics were increased in the order of ZS > ZR > ZF ceramics. The mixing ratio of natural zeolite to industrial by-product for maximum removal efficiency of heavy metal was 1:1 for ZS ceramics and 1:3 for ZR and ZF ceramics. The order of removal efficiency of heavy metal was observed to be ZS > ZR > ZF ceramics under the mixing ratio of 1:1 for ZS ceramics and 1:3 for ZR and ZF ceramics. The removal efficiency of heavy metal by ZS ceramics with 1:1 mixing ratio was Al 100%, Cd 54.6%, Cr 99.9%, Cu 98.7%, Fe 99.9%, Mn 42.2%, Ni 59.9%, Pb 99.8%, Zn 87.6%, respectively. In addition, the removal capacity of heavy metal by ZS ceramics was observed to be Al 2.01 mM/g, Cd 0.27 mM/g, Cr 1.02 mM/g, Cu 0.83 mM/g, Fe 0.95 mM/g, Mn 0.41 mM/g, Ni 0.55 mM/g, Pb 0.25 mM/g, Zn 0.70 mM/g, respectively. The comparative evaluation in the light of removal capacity, alkalinity increment, and coherence of ceramics showed the ZS ceramics had higher feasibility as a media than others for removal of heavy metals in acid wastewater.

Acid wastewater, Ceramics, Converter slag, Heavy metal, Industrial by-product, Zeolite

이재현 Jae Hyun Lee

DOI: Vol.28(No.2) 285-291, 2012

Generally, the rainfall and the influent of wastewater treatment plants (WWTPs) have strong relationship at the case of combined sewers. With the fact that the influent variations in terms of quantity and sewage quality is the most common and significant disturbance, the impact factor to the characteristics of sewage should be searched for. In this paper, the relationship between weather conditions such as humidity, temperature and rainfall and influent flowrate and contaminant concentration was analysed using factor analysis. Additionally, 3 influent types were deduced using cluster analysis and the distributions of operational variables were compared to the each groups by one-way ANOVA. The applied dataset were clustered to three groups that have the similar weather and influent conditions. These different conditions can cause the different operating conditions at WWTPs. That is, the Group 1 is for the condition with high humidity and rainfall, so DO concentration in the reactor was very high but MLSS concentration was very low because of too large flowrate. However, the Group 3 is classified to the case having low humidity, temperature, and rainfall, therefore, the SRT was the longest and the SVI was the highest due to the worst settleability in the winter for a year.

Influent characteristics, Multivariate statistical analaysis, Wastewater treatment plant, Weather conditions

김봉철 Bong Chul Kim , 부찬희 Chan Hee Boo , 이상엽 Sang Youp Lee , 홍승관 Seung Kwan Hong

DOI: Vol.28(No.2) 292-299, 2012

The objective of this study is to develop a novel method for evaluating forward osmosis (FO) membrane performances using a non-pressurized FO system. Basic membrane performance parameters including water (A) and solute (B) permeability coefficients and unique parameter for FO membrane such as the support layer structural parameter (S) were determined in two FO modes (i.e., active layer faces feed solution (AL-FS) and active layer faces draw solution (AL-DS)). Futhermore, these parameters were compared with those determined in a pressurized reverse osmosis (RO) system. Theoretical water flux was calculated by employing these parameters to a model that accounts for the effects of both internal and external concentration polarization. Water flux from FO experiment was compared to theoretical water fluxes for assessing the reliability of those parameters determined in three different operation modes (i.e., AL-FS FO, AL-DS FO, and RO modes). It is demonstrated that FO membrane performance parameters can be accurately measured in non-pressurized FO mode. Specifically, membrane performance parameters determined in AL-DS FO mode most accurately predict FO water flux. This implies that the evaluation of FO membrane performances should be performed in non-pressurized FO mode, which can prevent membrane compaction and/or defect and more precisely reflect FO operation conditions.

Forward osmosis, Membrane performance parameter, Solute permeability, Solute resistivity for diffusion, Water permeability

김선국 Seon Gok Kim , 이호식 Ho Sik Lee , 전태성 Tae Sung Jun

DOI: Vol.28(No.2) 300-304, 2012

It has a limitation to satisfy the phosphorus effluent criteria of 0.2 mg/L which will be reinforced from 2012 with the Biological Nutrient Removal (BNR) process. The chemical coagulation process has been operated in parallel with the biological treatment process for advanced treatment of phosphorous in the developed countries including Europe. However, the coagulation process has some disadvantages such as the desired goal may not be achieved without injecting the optimum dosage of the coagulant. This study developed the automatic control system to inject the optimum dosage of phosphorous coagulant into the coagulation process. The adopted coagulant was 10% Poly Aluminum Chloride (PAC) in this study. The automatic control system developed in this study was adopted for the treatment of the phosphorus from the effluent in SBR process. The automatic control system was composed of the data receiving part, the optimum coagulant dosage control part and the data transmit part. The result of the phosphorous advanced treatment of the SBR effluent using the automatic control system showed the removing efficiency over 95% consistently with the phosphorous concentration under 0.02~0.15 mg/L. The reproducibility analysis for checking the safety of automatic control system showed more than 95% correlation.

Automatic control system, Optimum dosage, Phosphorus, Sewage treatment plant

조호성 Ho Seong Cho , 김건하 Geon Ha Kim

DOI: Vol.28(No.2) 305-312, 2012

Avian influenza (AI) and foot and mouth disease (FMD) are two main contagious pathogenic viruses causing massive mortality burial, as burial is a primary measure to quaranteen the causative viruse(s). Biosecurity is a set of preventive measures designed to reduce the risk of propagation of infectious diseases. Main objectives of this paper were to discuss the needs of biosecurity and develop protocol outlines for environmental management of burial sites. Pathological characteristics of contagious viruses should be considered during environmental management practices. Current practice prescribes to minimize the potential for on-farm pollution and the spread of infectious diseases, policy makers should understand robust knowledge regarding biosecurity to make informed decisions on future legislation.

Biosecurity, Burial, Carcasses, Foot and mouth disease, Pathogen, Water quality

남선화 Sun Ha Nam , 안윤주 Youn Joo An

DOI: Vol.28(No.2) 313-319, 2012

Various nanomaterials may flow into the aquatic ecosystem via production, use, and treatment processes. Especially, gold nanoparticles (AuNPs) were categorized as manufactured nanomaterials presented by the Organization for Economic Cooperation and Development Working Party on Manufactured Nanomaterials (OECD WPMN) in 2010. AuNPs have been used in medical area, however, they were reported to induce cytotoxicity and oxidative DNA damage, as well as down-regulation of the DNA repair gene in mice and human cell lines. In this study, the aquatic toxicity data of AuNPs and gold ions were collected, with the specific test methods analyzed with respect to the form and size of AuNPs, test species, exposure duration, and endpoints. Currently, aquatic toxicity data of AuNPs and gold ions have been presented in 14 studies including 4 fish, 6 crustacean, 2 green algae, and 2 macrophytes studies, as well as a further 8 studies including 4 fish, 4 crustacean, 1 platyhelminthes, and 1 green algae, respectively. The AuNPs were 0.8-100 nm in size, as gold nanoparticles, gold nanorod, glycodendrimer-coated gold nanoparticles, and amine-coated gold nanoparticles. The tested endpoints were the individual toxicities, such as mortality, malformation, reproduction inhibition, growth inhibition and genetic toxicity such as oxidative stress, gene expression, and reactive oxygen species formation. The accumulation of AuNPs was also confirmed in the various receptor organs. These results are expected to be useful in understanding the aquatic toxicity of AuNPs and gold ions, as well as being applicable to future toxicity studies on AuNPs.

Aquatic ecotoxicity, Gold ions, Gold nanoparticles, Nanotoxicity

이한필 Han Pil Rhee , 정광욱 Kwang Wook Jung , 이복수 Bok Soo Lee , 함종화 Jong Hwa Ham , 손영권 Yeong Kwon Son

DOI: Vol.28(No.2) 320-331, 2012

A combination system of catch canal and constructed wetland was designed and suggested to improve water quality in gagricultural region of lower Dong-jin river basin. In order to evaluate an water quality improvement efficiency of the designed combination system, the NPS-WET model was applied in this study. Simulation result of the NPS-WET shown that the nutrient load removal rate of constructed wetland was BOD, T-N, T-P and SS was 30.7~39.0%, 46~60%, 40.7~57.0% and 68.2~74.7%, respectively. Nutrients reduction of constructed wetland was higher in growing season than winter season because vital activity of microorganism, macrophyte and algae was augmented with high air and water temperature. Effluents from constructed wetland can affect water-quality of catch canal drains, especially, water-quality on junction point to Dong-jin river. Water-quality improvement in low-flowed catch canal (Un-san) was more significant than in high-flowed catch canal (Won-pyeong). In conclusion, a feasible design of constructed wetland is necessary to treat large quantity of receiving water. The NPS-WET is useful tool for assessing water-quality improvement efficiency using constructed wetland.

Non-point sources, NPS-WET, Water-quality, Wetland modeling