• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2002.10a
• /
• pp.100-107
• /
• 2002

This study investigates the seasonal variation and spatial distribution characteristics of pollutant load, as executing the quantity valuation of pollutant load inflowing into Yeong-Il bay from on-land including the Hyeong-san river. Annual total pollutant generating rate from Yeong-Il bay region are 202ton to BOD, 620ton to SS, 42ton to T-N, 16ton to T-P respectively, if expressly point out, pollutant generating rate from the Hyeong-san river is the greatest, which BOD ratio is 78.2%, SS 88.5%, T-N 62.5%, T-P 73.1%. As calculating Tank model with input value of daily precipitation and evaporation of 2001 year in drainage basin of the Hyeong-san river, Estimated result of the annual total river discharge effluencing from this river is $830{\times}106m^3$. As result to estimating annual total effluence rate outflowing at the rivers from each drainage basins, annual total inflow pollutant rate are BOD 10,633ton, SS 19,302ton, T-N 15,369ton, T-P 305ton. The III basin which is population congestion region of the Pohang-city drain away a good many pollutant load than the V basin including the Neang-Chun with wide drainage area. Especially, a great many T-N than T-P inflow into Yeong-Il bay. The accumulation of pollutant load effluenced from on-land will happen on at the inner coast region of Yeong-Il bay, finally we would make a prediction that the water quality will take a bad turn.

• Spatial Information Research
• /
• v.20 no.5
• /
• pp.25-35
• /
• 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 Korean Society on Water Environment
• /
• v.34 no.5
• /
• pp.494-502
• /
• 2018

The purpose of this study was to understand distribution characteristics of organic matters through concentration of $BOD_5$, $COD_{Mn}$ and TOC in 31 streams in Han River region, and to establish the relationship among organic matter concentration, and discharge load and flow rate. Concentration of $BOD_5$ and TOC in 22 streams were above IV grade except 9, and the average 80.9 % of total organic matter (by TOC) accounted for dissolved organic type. Correlation among organic matter parameters were higher ($r^2$ > 0.78) and the relationship between TOC and $COD_{Mn}$ concentration was higher than $BOD_5$. Ratio of biodegradable organic matter/total organic matter in the 31 streams was estimated at 41.4 % with $BOD_5$ oxidation rate, and 78.0 % with $BOD_5/COD_{Mn}$ concentration ratio. Ratio of $NBOD/BOD_5$ concentration in four sites with $BOD_5/COD_{Mn}$ concentration ratio exceeding 1 ranged from 54.5 % ~ 79.3 %. Among 979 flow rate data measured at 31 streams, 87 % of measured data was below 0.1 cms and increased water pollution under low flow conditions. Correlation between $BOD_5$ concentration and $BOD_5$ discharge load in the watershed was low, and it was revealed that several streams have more $BOD_5$ delivery load than $BOD_5$ discharge load. Results suggest that many biodegradable forms of organic matter are being introduced into the stream from pollutant sources in the watershed.

• Journal of Wetlands Research
• /
• v.18 no.3
• /
• pp.301-312
• /
• 2016

This study has performed comparative analysis on characteristics of contaminated 35 tributaries on seasonal variation/point discharge load/pollutant distribution of water quality factors(8) in order to understand the effect of the watershed in Nakdong River Basin. As a results, the water quality of $BOD_5$(Biochemical Oxygen Demand), Chl-a(Chlorophyll a) and Fecal E. Coli shows II grade at tributaries of more than 50% without COD(Chemical Oxygen Demand), TP(Total Phosphate), TOC(Total Oxygen Carbon) and TN(Total Nitrogen) factors. The specific discharge(Q) were occupied about 54.4% (19 sites) as $0.05m^3/sec/km^2$ value. Among these results, the contaminant level of Dalseocheon, Hyeonjicheon, Seokkyocheon 1, Uriyeongcheon and Dasancheon was also high, which has to consider a discharged pollutant load(kg/day). The 35 major tributaries of Nakdong River were included in 7 mid-watershed, such as Nakdong Waegwan, Geumho River, Nakdong Goryung, Nakdong Changnyung, Nam River, Nakdong Milyang, Nakdong River Hagueon. Especially, the discharged pollutant load of Nam River and Geumho River also was high according to the amount of discharge such as Kachang dam, Gongsan dam and Nam river dam. Seasonal difference of the water quality factors such as $BOD_5$, TN, SS and Q was observed largely, on the other hand the TP and Chl-a was not. This is guessed due to the precipitation effect of site, biological and physicochemical degradation properties of pollutant and etc. The co-relationship between the seasonal difference and water quality factors was observed using a Pearson correlation coefficients. Besides, the Multiple Regression analysis using a Stepwise Regression method was conducted to understand the effect between seasonal difference and water quality factors/regression equations. As a result, the Multiple Regression analysis was adapted in the spring, summer and autumn without the winter, which was observed high at spring, summer and autumn in the order COD/TP, Chl-a/TOC, TOC/COD/$BOD_5$ water quality factors, respectively.

• Environmental Engineering Research
• /
• v.25 no.1
• /
• pp.123-128
• /
• 2020

Non-point source pollutant load reductions were calculated using the Hydrologic Simulation Program-Fortran (HSPF) model under the assumption that landuse pattern was changed according to land purchases. Upon the simulation of non-point pollutant and areas with high land purchase ratios to select a buffer zone, the Namgang dam Reach 11, Imha dam Reach 10, and the Reach 136 watershed of the main river were found to rank high for the construction of buffer zones. Assuming that the forms of the purchased lands were changed to wetlands, biological oxygen demand (BOD) loads were changed through the HSPF model. No changes of BOD were present in the Namgang dam and the Imha dam watersheds. BOD loads in Reach 136 according to landuse change were analyzed through a flow duration analysis based on the total maximum daily loads of the United States. The flow duration analyses undertaken to examine changes in BOD of main river Reach 136 watershed indicated a shift of 0.64 kg/d from 3.16 to 2.52 during high flow. The change of BOD under the conditions of moist, mid-range and dry were 11.9%, 9% and 4.5%. At the low flow condition, the variation range in the BOD load was from 0.58 kg/d to 0.41 kg/d.

• Journal of Environmental Science International
• /
• v.20 no.3
• /
• pp.361-372
• /
• 2011

This study analyzed the characteristics of stormwater runoff by rainfall type in orchard areas for two years. Effluents were monitored to calculate the EMCs and runoff loads of each pollutant. The runoff characteristics for nonpoint sources from vineyards were also inspected based on independent variables that affect runoff such as rainfall and rainfall intensity. The average runoff loads of each pollutant from vineyard_A and vineyard_B were found as follows: BOD 39.13 mg/$m^2$, COD 112.13 mg/$m^2$, TOC 54.98 mg/$m^2$, SS 1,681.8 mg/$m^2$, TN 18.29 mg/$m^2$, and TP 4.06 mg/$m^2$, which indicates that the COD's runoff load was especially high. The average EMCs from vineyard_A and vineyard_B, which represents the quality of rainfall effluent, were also analyzed: BOD 3.5 mg/L, COD 11.5 mg/L, TOC 5.2 mg/L, SS 211.7 mg/L, TN 1.774 mg/L, and TP 0.324 mg/L. This suggested that the COD, as an indicator of organic pollutants, is high in terms of EMCs as well. As rainfall increased, the EMCs of BOD, COD, TOC and SS kept turning upward. At a point, however, the high rainfall brought about dilution effects and began to push down the EMCs. Higher rainfall intensities led to the increase in the EMCs that displays the convergence of rainfall. Low rainfall intensities also raised pollutant concentrations, although the concentrations themselves were slightly different among pollutants.

• Journal of Korean Society on Water Environment
• /
• v.36 no.2
• /
• pp.98-108
• /
• 2020

The purpose of this study was to evaluate water quality in Hapcheon dam via using the Hydrological Simulation Program-Fortran (HSPF) model and applied livestock reduction scenarios. Hapcheon dam watershed input data for the HSPF model were established using the stream, land use, digital elevation map and meteorological data and others. The HSPF model was calibrated and validated using the observed water quality data from 2000 to 2016. For water quality simulation, we calculated the generated and discharge loads of the population, livestock, industry and land use following the guideline provided by the Ministry of Environment. The pollutant data were obtained from National Institute of Environmental Research (NIER). The monthly discharge load were estimated by applying the delivery rate. The calibration and validation results showed that the annual mean BOD had a difference of 0.22 mg/L and an error of ±13 %, T-N had a difference of 0.66 mg/L and an error of ±16 % and T-P had a difference of 0.027 mg/L and an error of ±13 %. In order to evaluate the nonpoint pollutants management effects, we applied livestock reduction scenarios because livestock consists of the largest portion of pollutants. As a result of the 20 % of livestock reduction, BOD, T-N and T-P decreased by 3 %, 1 % and 3 %, respectively. When 40 % of livestock reduction was applied, BOD, T-N and T-P decreased by 5 %, 3 % and 4 %, respectively. Based on the results of this study, effective pollutant management methods can be applied to improve the water quality and achieve the target water quality of Hapcheon dam watershed.

• Journal of Korean Society on Water Environment
• /
• v.23 no.6
• /
• pp.913-919
• /
• 2007

This study was conducted to develop a model equation to estimate the delivered point and nonpoint pollutant loads, which are critical factor to determine the water quality of watersheds. The model equation was developed by considering various factors such as biological removal and delivered distance of pollutants, basin shape and geomorphic runoff condition. The parameters for the model equation were estimated in 3 periods, which are October to March, April to June, and July to September. As a parameter, ${\alpha}_p$, ${\alpha}_n$, ${\beta}$, a and b for $BOD_5$-delivered pollutant loads were estimated to be 0.010~0.0155, 0.051, -0.033, 0.018~0.050 and 0.93, respectively. For T-N, ${\alpha}_p$, ${\alpha}_n$, ${\beta}$ a and b were estimated to be 0.0060~0.0140, 0.014, -0.02, 0.044~0.079 and 0.93, respectively. The same parameters for T-P were estimated to be 0.0160, 0.014, -0.0250, 0.015 and 1.21, respectively. The relationship, $E^2$ (Model efficiency), between observed and calculated delivered pollutant loads showed 0.65 for $BOD_5$, 0.81 for T-N, and 0.66 for T-P, respectively. Consequently, the model equation is effective to estimate delivered pollutant loads for TMDL.

• Journal of Korea Water Resources Association
• /
• v.40 no.8
• /
• pp.585-600
• /
• 2007

The hydrologic cycle and BOD pollutant loads of all sub-watersheds were analyzed using HSPF (Hydrological Simulation Program-Fortran). At first, sensitivity analyses to water quantity (peak discharge and total volume) and quality (BOD peak concentrations and total loads) were conducted and some critical Parameters were selected. For more precise simulation, the study watershed was divided into four parts according to the landuse characteristics and used climate data and so calibrated and verified respectively. It was found that as the urban area ratio increases in the downstream direction, baseflow decreases (11.1 % $\rightarrow$ 5.0%) and the ratio of direct runoff volume(42.5 % $\rightarrow$ 56.9 %), BOD concentration (3.3 mg/L $\rightarrow$ 15.0 mg/L) and unit loads (55.4 kg/ha/year $\rightarrow$ 354.5 kg/ha/year) increase.

• Korean Journal of Environmental Agriculture
• /
• v.23 no.1
• /
• pp.41-46
• /
• 2004

The influence of pollutant loads on the water quality in Jeongeupcheon of Dongjin river was evaluated from Jan. 2002 to Dec. 2003 for two years. The range of pH in water was $6.87{\sim}7.53$. The EC level in upstream ranged from 83 to $95\;{\mu}s/cm$ with the highest value in autumn. The BOD level in upstream rang ed from 0.61 to 1.27 mg/L, which would be I grade according to water quality criteria by Ministry of Environment, but that in downstream was III grade. The average T-N level in midstream ranged from 6.10 to 10.84 mg/L which was the highest values throughout the stretch of the river. The average T-P levels ranged from. 0.41 to 0.98 mg/L Jeongeupcheon was suitable for the agricultural usage based upon one year analysis of river water quality. The effluent loads of BOD was high in midstream (J4) with 553 kg/day. The major sources of T-N loads were livestock, population, land use, and industry in order. The effluent loads of T-N was high in J4 by population and industry while that of T-N was high in J5 and J6 by livestock and land use. The delivered loads of T-N was high in downstream The delivered loads of T-P was low as compared with those of BOD and T-N. The delivery ratio of T-N ranged from 6 to 38%.