• Journal of Wetlands Research
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• v.18 no.3
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• pp.292-300
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• 2016

Diverse and comprehensive countermeasures were established to prevent water pollution in coastal areas such as constructed wetlands(CW).This study was conducted to assess the water quality improvement through CW constructed along the shoreline of Hwaseong coastal reservoir. The CW is located in Hwaseong-si, Gyeonggi-do and consisted of a forebay and a wetland. The CW was monitored twice during rainy days and 10 times during dry days. The monitoring results indicated that in and out flowrates were highly correlated with COD and TN loads. COD, TN and TP concentrations in the forebay was lower during dry days than rainy days. However, concentration and mass removal efficiencies of COD, TN and TP were greater during rainy days. In addition, the volume flowing into the CW was less compared to the outflow during rainy days indicating that the CW efficiently reduced the runoff volume. The overall pollutant removal efficiency of the CW were at least 50% for TSS, 20 to 35% for TP, and 26 to 94% for TN. The data gathered may be used to improve the pollutant removal efficiency of the system in the future.

• Spatial Information Research
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• v.20 no.5
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• pp.25-35
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• 2012

This study compared the influence of water quality according to the data sources of spatial information. Firstly, land cover map was constructed through image classification of Daecheong-dam basin and the accuracy of image classification from satellite image showed high as 88.76% in comparison with the large-scaled land cover map in Ministry of Environment, to calculate Event Mean Concentration (EMC) by land cover that impact on the evaluation of nonpoint source pollutant loads. Also curve number and direct runoff were calculated by spatial overlay with soil map and land cover map from image classification. And Seokcheon and Daecheong-Dam basin showed high in the analysis of curve number and direct runoff. Samgacheon-Joint and Sokcheon-Downstream basin showed high in the nonpoint source pollutant loads of BOD from direct runoff and EMC. And Samgacheon-Joint and Bonghwangcheon- Downstream basin showed high in the nonpoint source pollutant loads of TN and TP. Nonpoint source pollutant loads from image classification were compared with those by the land cover map from Ministry of Environment to present the effectivity of nonpoint source pollutant loads from satellite image. And Daecheong-Dam Upstream basin showed high as 10.64%, 11.70% and 20.00% respectively in the errors of nonpoint source pollutant loads of BOD, TN, and TP. Therefore, it is desirable that spatial information including with paddy and dry field is applied to the evaluation of nonpoint source pollutant loads in order to simulate water quality of basin effectively.

• Journal of Korea Water Resources Association
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• v.55 no.11
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• pp.877-886
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• 2022

This study was carried out to analyze how the flow and water quality of the Sangsa Lake (juam control basin) change according to future climate change and what countermeasures are needed. Aquatic Ecosystem Model) was used in conjunction. As climate change scenarios, RCP (Representative Concentration Pathways) 4.5 and RCP 8.5 scenarios of AR5 (5th Assessment Report) according to the Intergovernmental Panel on Climate Change (IPCC) were used. For the climate change scenario, detailed data on the Sangsa Lake basin were used by the Korea Meteorological Administration, and after being evaluated as a correction and verification process for the 10-year period from 2012 to 2021, the present, 2025-2036, 2045- The summer period from June to August and the winter period from December to February were analyzed separately for each year by dividing it into 2056 and 2075-2086. RCP 8.5 was higher than RCP 4.5 as an arithmetic mean for the flow rate of the watershed of the superior lake for the entire simulation period, and TN and TP also showed a tendency to be higher at RCP 4.5. However, in RCP 8.5, the outflow of pollutants decreased during the dry season and the outflow of pollutants increased during the summer, indicating that the annual pollutant outflow was concentrated during the flood season, and it is analyzed that countermeasures are needed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.1B
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• pp.153-160
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• 2008

To estimate microbial contaminant loading discharged from diffuse sources, rainfall runoff of six rainfall events were monitored at three study watersheds of forestry and agricultural land use. Monitored indicator microorganism constituents were total coliform (TC), fecal coliform (FC), Escherichia coli (EC), and fecal streptococcus (FS). Soil loss during elevated flow rate caused higher suspended solid concentrations. Indicator microorganism concentrations were closely related with flow rate. TC event mean concentration (EMC) from unpolluted forestry was $5.3{\times}10^3CFU/100ml$, FC EMC was $1.4{\times}10^3CFU/100ml$, EC EMC was $1.1{\times}10^3CFU/100ml$, and FS EMC was $2.9{\times}10^2CFU/100ml$. From a watershed with agricultural-forestry land use, TC EMC was $1.7{\times}10^5CFU/100ml$, FC EMC was $8.5{\times}10^4CFU/100ml$, EC EMC was $8.9{\times}10^4CFU/100ml$, and FS EMC was $3.4{\times}10^4CFU/100ml$. Mixed land use of agricultural-forestry with bigger area, TC EMC was $1.9{\times}10^5CFU/100ml$, FC EMC was $9.6{\times}10^4CFU/100ml$, EC EMC was $7.0{\times}10^4CFU/100ml$, and FS EMC was $5.1{\times}10^4CFU/100ml$.

• Journal of Soil and Groundwater Environment
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• v.8 no.2
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• pp.9-18
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• 2003

Sampling of waters from each stage of treatment system (Successive Alkalinity Producing System; SAPS), tailings seepage, and spring near the Hanchang coal mine of Kangwon Province were carried out seasonally and analyzed to evaluate the source and possible path of groundwater contamination by acid mine drainage (AM). Sulfur isotope compositions were measured to identify the origin of groundwater contaminations and the sulfate reduction processes in the SAPS. Low pH and high metal concentration of spring water indicates possibility of the groundwater contamination by AMD. Removal efficiency of acidity of the SAPS was 18.17 g/$\textrm{m}^2$/day on an average and the metal removal efficiency was almost 100%, which was higher than those of other treatment systems. However, no appreciable decrease of sulfur content and almost similar sulfur isotope compositions of water from each stage of the treatment system may suggest incomplete or very poor sulfate reduction by sulfate reducing bacteria. Chemical and sulfur isotope compositions showed that spring water was contaminated by seepage from mine tailings. And seepage of stonewall, a part of treatment system was affected by both tailings seepage and mine adit drainage. In this study site, the treatment system was constructed for the only AMD from mine adit not for tailings seepages, which resulted in the groundwater contamination from tailing seepages. Similar situation is expected in other abandoned coal mine areas.

• Korean Journal of Ecology and Environment
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• v.39 no.4 s.118
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• pp.489-497
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• 2006

The feasibility of the Natural and Ecological Wastewater treatment System (NEWS) was examined for rural wastewater treatment in Korea. The intermittent trickling biofilter with high hydrophilic filter media was used for pretreatment for suspended solids and organic pollutants. The subsequent constructed wetland with porous granule materials was used for promoting nutrient removal. The results show that the removal efficiencies of the system were high with respect to the water quality parameters except COD. Even if the effluent from the biofilter did not meet the guidelines for wastewater treatment plant effluent in Korea in terms of $BOD_5$ and TN, the final effluent of the system meets the guidelines us to good performance of the constructed wetland. The regression analysis between pollutant loading rate and removal rate indicated that the system could have stable removal for SS, $BOD_5$, TN, and TP in the given influent ranges. The analysis in the winter period indicated that the wetland covered with transparent polycarbonate glass had the statble performance during the winter period dus to increase of temperature inside the wetland without any heating system. With the stable performance, effective poilutant removal, low maintenance, and cost-effectiveness, the NEWS could be considered as an alternative treatment system for decentralized regions and rural communities in Korea.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.403-403
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• 2021

비점오염물질은 강우에 의해 유출되며 계절적, 자연적 편차가 크게 나타나고, 오염원이 광범위하게 산재하고 있어 오염물질의 발생량과 부하량의 관리가 쉽지 않다. 따라서 비점오염원 관리지역은 오염물질이 하천에 미치는 수질 특성을 파악하는 것이 중요하다. 그러나 수질항목만으로 하천의 수질 특성을 파악하기에는 어려움이 있으며, 수질 특성을 파악하기 위해 다양한 분석방법이 필요하다. 본 연구에서는 비점오염원 관리지역 중 골지천 유역의 수질 특성을 파악하기 위해 통계분석 기법을 활용하여 수질항목간의 상관관계를 분석하고자 하였다. 2017년부터 2019년까지 골지천 유역 내 5개 지점에 대하여 비강우시 23회, 강우시 지점별 173회~196회의 모니터링 결과를 이용하였으며, EC, 탁도, BOD₅, SS, T-N, T-P, TOC의 수질항목을 이용하여 Pearson 상관관계 분석을 실시하였다. 상관관계 분석 결과 비강우시 분석 결과 EC는 -0.06~-0.32, T-N은 0.19~0.37로 낮은 상관성을 갖는 것으로 나타났으며, EC와 T-N을 제외한 탁도와 BOD₅, SS, T-P, TOC의 경우 서로 0.6 이상의 상관성을 갖는 것으로 나타났다. 특히, 탁도와 SS, T-P, T-P와 TOC는 0.9 이상의 높은 상관성을 갖는 것으로 나타났다. 강우시 분석 결과 EC는 비강우시와 유사하게 -0.07~-0.24로 낮은 상관성을 갖는 것으로 나타났으며, TOC를 제외한 탁도, BOD₅, SS, T-N, T-P의 경우 서로 0.6 이상의 상관성을 갖는 것으로 나타났다. TOC의 경우 BOD₅, SS와 0.6 이상의 상관성을 갖는 반면 탁도, T-N, T-P와는 0.45, 0.44, 0.57로 다른 항목에 비해 다소 낮은 상관성을 갖는 것으로 나타났다. 비강우시 T-N은 기저 유출에 의한 영향으로 높은 농도를 나타내 다른 항목에 비해 상관성이 낮은 것으로 나타났으며, 강우시에는 비점오염물질의 유입으로 인하여 모든 항목에서 비슷한 상관성을 보이는 것으로 나타났다. 본 연구 결과 탁도와 SS, T-P의 상관성이 비강우시 0.93, 강우시 0.78로 상당히 높은 것으로 나타나, 탁도를 측정하여 SS와 T-P로 환산하여 측정하는 방법에 대한 기초자료로 활용될 수 있을 것으로 판단된다. 그러나 연구 유역의 지형적 특성이 배제되었기 때문에 추후에 이를 반영한 연구가 필요할 것으로 판단된다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.12
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• pp.7443-7450
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• 2014

To resolve shortcomings of high-rate anaerobic processes, such as high upward flow velocity, this study sought to improve the structure of the high-rate anaerobic reactor and evaluate its performance. The improved reactor was manufactured by adjusting the diameter and dividing the reactor into three parts. The evaluation of the structurally improved reactor revealed that the reactor could stabilize a single circuit, and prevent the accumulation of solid matter and leakage of microbes, thereby stabilize the microbes. In the process of anaerobic digestion, an increase in pH and alkalinity within the reactor was presumably attributed to bicarbonate created in the process of organic matter decomposition and due to the re-dissolution of some biogas. To maintain a high rate of organic matter removal, the reactor should be operated with more than 9 hrs of HRT and an organic matter load of under $10.kgTCODcr/m^3{\cdot}d$. The methane gas generated in the anaerobic digestion process showed a high content of 65~83 % at the organic matter load of over $7.7kgTCODcr/m^3{\cdot}d$. per removal of CODcr. The methane quantity was generated at $0.10{\sim}0.23m^3CH_4/kgCOD_{rem}$, showing that it was smaller than the theoretical methane generation amount (0.35) in the STP state. In the latter part of high-rate anaerobic process, an advanced treatment process was required to remove nitrogen.

• KSBB Journal
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• v.14 no.6
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• pp.688-695
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• 1999

Biodegradation of the reactive dye, Remazol Black B was investigated in an upflow anaerobic sludge blanket(UASB) reactor. Important parameters studied include dye concentration(20-60 mg/L), glucose concentration as a co-substrate(1,000-3,000 mg/L), hydraulic retention time(3-24 hr), and influent pH(6.0-8.0). Under most conditions tested, the molecules of Black B were degraded readily and completely according to HPLC chromatograms. However, the color removal efficiency based on spectroscopic measurement was always approximately 75%. This suggests that the degradation products have some color intensity corresponding to 25% of the original dye molecules. The maximum influent dye concentration which satisfies the legal discharge limit of color intensity of 400 ADMI was 13 mg/L. and the highest removal rate at this dye concentration was 104 mg/L${\cdot}$day.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.4
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• pp.619-627
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• 2000

Biodegradation of the C. I. Reactive Blue 114 was investigated in an upflow anaerobic sludge blanket (UASB) reactor. Important parameters studied include dye concentration, the kind and concentration of carbon source, hydraulic retention time (HRT), and influent pH. Glucose was found to be a better co-substrate than the mixture of volatile fatty acids (VFAs), although its concentration did not affect dye removal efficiency in the range of $1000{\sim}3000mg/{\ell}$. When HRT increased from 6 hr to 24 hr, dye removal efficiency increased up to 12 hr and remained almost constant thereafter at about 40%. When influent pH was varied in the range of 6.0~8.0, the effluent pH was varied in the range of 6.8~7.5 with maximum efficiency at pH 7.0. The highest dye removal rate obtained was $52mg/{\ell}{\cdot}day$, while the maximum dye load to meet the discharge limit of color intensity was estimated to be $46mg/{\ell}{\cdot}day$ at HRT of 12 hr and an influent glucose concentration of $2200mg/{\ell}$.