• 한국물환경학회지
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• 제25권5호
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• pp.689-696
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• 2009

Unit load approach has been used to estimate the non-point pollutant load in Total Water Pollution Load Management System (TWPLMS). In this study, locally applicable unit loads for road and parking lot were developed based on the measurements of 9 rainfall events from 2007 to 2008 in Yongin city of Gyeongan stream watershed. Observations showed that stormwater runoff began at low precipitation (>1 mm) and peak pollutant concentration occurred at the beginning of the runoff because of impervious nature of the sites. Averaged event mean concentrations (EMCs) of road (parking lot) were estimated as COD 105.36(62.69) mg/L, BOD 15.94(13.20) mg/L, TSS 183.45(66.52) mg/L, T-N 4.63(3.28) mg/L, T-P 0.45(0.39) mg/L. Higher EMCs at the road than parking lot may reflect heavier traffic. Unit loads Estimated from the EMCs and 10 year average rainfall data were COD $331.17kg/km^2{\cdot}day$, BOD $50.20kg/km^2{\cdot}day$, TSS $580.13kg/km^2{\cdot}day$, T-N $14.68kg/km^2{\cdot}day$, T-P $1.43kg/km^2{\cdot}day$ in the road and COD $186.59kg/km^2{\cdot}day$, BOD $39.22kg/km^2{\cdot}day$, TSS $199.15kg/km^2{\cdot}day$, T-N $9.70kg/km^2{\cdot}day$, T-P $1.16kg/km^2{\cdot}day$ in the parking lot. The estimated unit loads are not so comparable to the ones listed in TWPLMS technical guideline and published data that locally developed unit loads should be used to estimate non-point pollutant loads.

• 한국도로학회논문집
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• 제9권4호
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• pp.185-192
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• 2007

최근의 환경정책은 신설되는 도로에 대하여 비점오염저감시설 설치의무화를 요구하고 있다. 또한 도로건설시 및 유지관리시에는 발생가능한 비점오염물질을 예측하고 이를 저감할 수 있는 방향으로 노선의 계획 및 설계와 더불어 다양한 비점저감방안을 수립할 것을 요구하고 있다. 비점오염원 및 비점오염물질을 관리하기 위해서는 우선 유역의 토지이용도를 분석하여 강우시 배출되는 오염물질의 종류와 양을 산정해야 한다. 특히 도로의 경우, 발생되는 비점오염물질의 원단위가 별도로 존재하지 않고 대지항목의 오염발생원단위를 사용하고 있기에 적용함에 있어서 많은 어려움을 겪고 있는 실정이다. 따라서 본 연구는 포장지역 중 고속도로 영업소를 대상으로 강우시 유출되는 강우유출수의 특성을 파악하여, 이러한 토지이용에서의 비점오염물질 유출특성과 부하량을 산정하고자 한다. 영업소 토지이용의 경우 많은 차량이 속도를 급격히 줄이는 토지이용지역으로 브레이크 패드, 각종 오일 및 엔진파트 등으로부터 많은 양의 오염물질이 축적되고, 포장률이 높아 강우시 다량의 오염물질이 유출되는 지역이다. 본 연구를 통해서 영업소 토지이용지역에서의 초기강우현상을 수리수문 및 농도곡선을 통해 확인할 수 있었다. 또한 EMC로부터 단위면적당 부하량과 강우지속시간당 부하량을 산정하였으며, 이러한 값은 영업소 유지관리시 인근수계에의 환경적인 영향을 해석하기 위한 기초자료로 활용될 수 있다. 강우지속시간당 유출되는 평균부하량은 TSS의 경우 $533.7mg/m^2-hr$, COD $396.2mg/m^2-hr$, TN $17.0mg/m^2-hr$, TP $4.8mg/m^2-hr$로 산정되었다.

• 한국환경과학회지
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• 제23권1호
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• pp.7-23
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• 2014

This study estimates unit for the nonpoint source(NPS), classified according to the existing Level-1(large scale) land cover map, by monitoring the measurement results from each Level-2(medium scale) land cover map, and verifies the applicability by comparison with previously calculated units using the Level-1 land cover map. The NPS pollutant loading for a basin is evaluated by applying the NPS pollutant unit to Dongcheon basin using the Level-2 land cover map. In addition, the BASINS/HSPF(Better Assessment Science Integrating point & Non-point Sources/Hydrological Simulation Program-Fortran) model is used to evaluate the reliability of the NPS pollutant loading computation by comparing the loading during precipitation in the Dongcheon basin. The NPS pollutant unit for the Level-2 land cover map is computed based on precipitation measured by the Sangju observatory in the Nakdong River basin. Finally, the feasibility of the NPS pollutant loading computation using a BASINS/HSPF model is evaluated by comparing and analyzing the NPS pollutant loading when estimated unit using the Level-2 land cover map and simulated using the BASINS/HSPF models.

• 한국물환경학회지
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• 제24권3호
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• pp.291-296
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• 2008

Pollutant unit load developed by Ministry of Environment (MOE) in 1995 has been a tool commonly used for water quality management and environmental policy decision. In spite of the convenience of the method in application, the shortcoming of the method has been criticized especially for nonpoint source pollution from paddy field. In this paper the estimation procedures of pollutant unit load from paddy field in the major river basins (Han, Nakdong, Geum, and Youngsan river) were investigated, and some suggestions of improvement measures of the unit-load estimation were made. The investigation showed that the distributions of rainfall, run-off, and run-off ratio, which are the most important factors affecting discharge amount of pollutants, were not similar among river basins. Such differences seemed to result in a greater unit loads estimation at Han river and at Nakdong river watersheds compared to the others. Therefore, it is not likely to be rationale to compare unit load among the watersheds without consideration of such differences. We conclude that estimation of unit-load through an intensive monitoring of pollutant discharge is crucial for better estimation of unit-load. When such an intensive monitoring is not easy due to labor and expense restriction, we suggest that unit-load should be estimated based on the storm-events which is a representative rainfall-runoff event of the area.

• Fisheries and Aquatic Sciences
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• 제6권3호
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• pp.149-154
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• 2003

The characteristics of pollutant loads from the various sources and seawater quality in Kwangyang Bay were evaluated. Total flow rate was estimated to be $10,868,066.8 m^3/day$ with a flow rate of R2l (the Seomjin River) as the highest one. Total COD, TN and TP loads of the input rivers and the ditches were about 27,591.8, 25,029.6 and 586.4 kg/day, respectively. Wastewater discharging loads was the greatest contributors to pollutant loads in the inner part of Kwangyang Bay. COD values in the inner part of the bay was over 3.0 mg/L, which exceeded the seawater quality criteria III of Korea. The average values of DIN and DIP were 8.62 ${\mu}gN/L\;and\;1.26\;{\mu}gP/L$, respectively. The limiting factor for algal growth was DIN. In he total discharging loads of the watershed from unit loading estimations, BOD, TN and TP were 9,132.3, 2,727.2 and 304.2 kg/day, respectively. In addition, municipal sewage by the population as pollution sources and the city of Kwangyang as administrative district had the highest loads. For a appropriate water quality recovery of Kwangyang Bay, it is suggested that it is essential to estimate reduction rate of total pollutant loads by water quality modeling.

• 한국물환경학회지
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• 제30권6호
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• pp.585-595
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• 2014

The temporal trends of the prioritized toxic water pollutants generated and discharged from the industrial facilities in the Geum-River basin, Korea were analyzed with the results of the nationwide Water Pollution Source Survey conducted in 2001 - 2012. The statistical results indicated rapid increase in the volume of raw toxic wastewaters whereas the amount of each toxic pollutant kept fluctuating for 12 years. Serious discrepancies in the survey data of the same type of industries demonstrated a low reliability of the survey result, which stemmed from several error factors. A unit-load for each type of industrial facility was devised to estimate the amount of prioritized toxic water pollutant based on the total volume of industrial wastewater generated from the same type of industrial facilities. The supplementary measures with an effective permit issuance policy and adding survey parameters of terminal wastewater treatment plants to use them as references to the Water Pollution Source Survey were suggested as means to minimize the errors associated with the false reports from the industries.

• 한국물환경학회지
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• 제31권6호
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• pp.700-714
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• 2015

The characteristic of the water quality and pollutant discharge was analyzed at the units watershed of the total amount management in Han-river basin, and after classified in a similar area by multivariate statistical analysis, the main trend such as the water quality trend and pollutant discharge characteristic were analyzed. As a result of this study, the density of the pollutant at the unit watershed is not necessarily identified as discharge density, and the primary management watershed and targeted substances were analyzed depending on the operating status of the environmental infrastructure in watershed and the main pollution factor and discharge path per pollutants. As a result of cluster analysis, watersheds were classified into four groups according to discharge characteristics. It will be used when selecting target area of primary management that is appropriate to the characteristics of each river and establishing efficient water quality improvement plans.

• 환경영향평가
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• 제18권5호
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• pp.281-291
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• 2009

In Total Water Pollutant Load Management System of Korea, unit load approach based on land register data is currently used for the estimation of non-point pollutant load. However, a problem raised that land register data could not always reflect the actual land surface coverages which determine runoff characteristics of non-point pollution sources. As a way to overcome this, we tried to establish quantitative relationships between the aerial images (0.4m resolution) which reflect actual land surface coverages and the land registration maps according to the 19 major designated land-use categories in Kyeongan watershed. Analyses showed different relationships according to the land-use categories. Only a few land-use categories including forestry, road and river showed essentially identical and some categories such as orchard, parking lot and sport utility site showed no relationships at all between image data and land register data. Except for the two cases, all the other categories showed statistically significant linear relationships between image data and land register data. The analyses indicate that using high resolution aerial maps is a better way to estimate non-point pollutant load. If the aerial maps are not available, application of the linear relationships as conversion factors of land register data to image data could be an possible option to estimate non-point pollutant loads for the specific land-use categories in Kyeongan watershed.

• 한국물환경학회지
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• 제25권1호
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• pp.125-135
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• 2009

Reliable long-term flows by SWAT-K model were applied to the relationship between stream flow and pollutant load derived from 8-day measured data of Ministry of Environment (MOE) in order to obtain continuous loadograph and evaluate accuracy in water quality modeling for the Chungju dam watershed. The measured flow were compared with flow duration curve from the model, and it showed that measured values corresponded to the almost full range of stream flow conditions except at Odae A. And there was significant relationship ($R^2=0.60{\sim}0.97$) between measured flow and water quality load at all unit-watersheds. Applying this relationship to simulated flows, continuous loadograph was obtained and compared with modeled pollutant loads. Although there were some differences during some dry and flood seasons, those were not significant and overall trend showed a good agreement. From the results, we would be able to derive a continuous loadograph based on measured data at total maximum daily loads (TMDLs) unit-watersheds on a national scale, in which stream flow and water quality have been measured at 8-day intervals since 2004, and this could be helpful to utilize distributed water quality models with difficulty in calibrating and validating parameters from lack of measured data at present.

• 한국농공학회지
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• 제44권2호
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• pp.136-147
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• 2002

Characteristics of unit loads of pollutants were investigated at a paddy fields area(Soro-ri) with large-scaled plots on loam soil during irrigation seasons of 1999 ∼2000. The average irrigation requirement of experimental paddy area are estimated at over 3,000 mm. The unit loads of pollutants in paddy fields area are determined by subtracting irrigation water load from outflow load (percolated and surface outflow loads). Surface outflow load in rainy days was calculated using the relationships of discharge and load, which are grouped into fertilizing and non-fertilizing periods. The ratios of the surface outflow load in rainy days to the total surface outflow load are 16.4% for T-N, 26.8% for T-P, and 23.3% far CODc,. The unit loads of pollutants show month-to-month and year-to-year variations, and monthly unit load of pollutants can show negative values, indicating that the paddy area acts as the pollutants sink. The average unit loads of the pollutants during irrigation seasons were estimated at 18.2 kg/ha fur T-N, 0.31 kg/ha for T-P, and 43.3 kg/ha for CODc,, which are smaller than the reported values for Kosei area in Japan.