This research aims to use administrative raw data on water environment-related pollutants by pollutant group in analyzing pollutant data conversion and other problems with a view to planning and evaluating the total maximum daily load (TMDL), to present improvement measures, and to use actual survey...
This research aims to use administrative raw data on water environment-related pollutants by pollutant group in analyzing pollutant data conversion and other problems with a view to planning and evaluating the total maximum daily load (TMDL), to present improvement measures, and to use actual surveyed data (sewer flow) in calculating an appropriate practical discharge load with regard to coefficient of sewer inflow - which has an effect on the non-point discharge load - of various factors unilaterally applied under the TDML technology guideline. In order to analyze pollution load difference associated with the application of space information, discharge load changes were analyzed through the implementation assessment of target regions, and by comparing the planned load and the actual discharge load. Also, of factors affecting pollutant load discharge load characteristics, interception area, points according to the application of coefficient of sewer inflow, and changes in non-point discharge load were reviewed, and pollutant load discharge characteristics were assessed when applying the coefficient of sewer inflow based on the basic unit provided in existing literature and on the past actual data. Causes for load deviations by stage were analyzed using the existing pollutant survey methods and the uniform calculation method under the technology guideline, revealing the following problems. 1. Uncertainty of raw data due to failure to construct a raw data comparison and verification system 2. When using domestic raw data, data is lacking, thereby disabling the reflection of actual sewage treatment rate, domestic consumption, and non-domestic consumption 3. When using additional data to compare and verify pollutants, there is a lack of time and technical manpower under the current municipality conditions 4. Due to frequent changes of TDML technology guideline, it is difficult to manage continuous load. 5. The calculation method using the technology guideline uses uniform basic units and factors, thereby failing to consider actual conditions and consequently leading to the calculation of an unrealistic load. In order to resolve above problems and to calculate and forecast more accurate pollution load, the pollutant calculation improvement method and the pollution load calculation method were reviewed; thus, a conclusion was made as follows to manage continuous and continual load. 1. In order to secure the reliable basic data for calculating the TDML pollution load, sewage treatment zones were derived by area number from attached cadastral maps and sewerage-network maps using GIS, and they were matched with raw domestic pollutant data (area number by household), thereby obtaining results that could reflect actual sewage treatment rates. 2. The sewer inflow coefficient 0.088, applied under the current technology guideline, provides discharge loads that fail to reflect real conditions when calculating the sewer overflow load in some territorial areas and unit watersheds. Thus, to calculate realistic discharge load, the coefficient of sewer inflow was calculated using actual surveyed data, and the load was calculated by evaluating the net rainwater inflow excluding the I/I value from the “rainfall-sewer inflow empirical formula." The coefficient of sewer inflow, calculated based on sewer flow data measured in sewer BTL projects of Jeonju City and Jeongeup City, was 0.204 for Jeonju, and 0.410 for Jeongeup, making Jeongeup double Jeonju. 3. The correlation between the calculated coefficient of sewer inflow and percentage of impervious areas was analyzed, revealing that the coefficient of determination (R2) was 0.888, suggesting a very high coefficient. Using the empirical formula, the percentage of impervious areas was calculated within the sewage treatment districts in Gunsan, Iksan, and Gimje, and the corresponding coefficient of sewer inflow was calculated as 0.248, 0.213, and 0.174, respectively. Thus, it is concerning that the load calculation may be distorted if the sewer inflow coefficient 0.088 under the current TDML technology guideline is uniformly applied, so there is a need to apply the coefficient of sewer inflow by sewage treatment district considering percentage of impervious areas. 4. It was found that as the coefficient of sewer inflow increased, the non-point discharge load increased significantly, and this increase in non-point discharge load is attributable to an increase in sewer overflow load. When the Ministry of Environment compared CSOs load and sewer inflow coefficients 0.3 and 0.31 in order to devise a plan for reducing CSOs in the Seamangeum basin, revealing that when applying 0.31, a nearly similar sewer overflow load was calculated. The sewer overflow load in Iksan and Gimje of the MOE CSOs project areas was calculated and its similarity was reviewed, and using the 2012 implementation assessment load, sewer overflow load was calculated. Likewise, since implementation assessment is based on the master plan rainfall and the sewer discharge percentage, this study used the 2012 rainfall condition and sewer discharge percentage and conducted the assessment, revealing a –2 % difference for Iksan and a +14 % difference for Gimje.
This research aims to use administrative raw data on water environment-related pollutants by pollutant group in analyzing pollutant data conversion and other problems with a view to planning and evaluating the total maximum daily load (TMDL), to present improvement measures, and to use actual surveyed data (sewer flow) in calculating an appropriate practical discharge load with regard to coefficient of sewer inflow - which has an effect on the non-point discharge load - of various factors unilaterally applied under the TDML technology guideline. In order to analyze pollution load difference associated with the application of space information, discharge load changes were analyzed through the implementation assessment of target regions, and by comparing the planned load and the actual discharge load. Also, of factors affecting pollutant load discharge load characteristics, interception area, points according to the application of coefficient of sewer inflow, and changes in non-point discharge load were reviewed, and pollutant load discharge characteristics were assessed when applying the coefficient of sewer inflow based on the basic unit provided in existing literature and on the past actual data. Causes for load deviations by stage were analyzed using the existing pollutant survey methods and the uniform calculation method under the technology guideline, revealing the following problems. 1. Uncertainty of raw data due to failure to construct a raw data comparison and verification system 2. When using domestic raw data, data is lacking, thereby disabling the reflection of actual sewage treatment rate, domestic consumption, and non-domestic consumption 3. When using additional data to compare and verify pollutants, there is a lack of time and technical manpower under the current municipality conditions 4. Due to frequent changes of TDML technology guideline, it is difficult to manage continuous load. 5. The calculation method using the technology guideline uses uniform basic units and factors, thereby failing to consider actual conditions and consequently leading to the calculation of an unrealistic load. In order to resolve above problems and to calculate and forecast more accurate pollution load, the pollutant calculation improvement method and the pollution load calculation method were reviewed; thus, a conclusion was made as follows to manage continuous and continual load. 1. In order to secure the reliable basic data for calculating the TDML pollution load, sewage treatment zones were derived by area number from attached cadastral maps and sewerage-network maps using GIS, and they were matched with raw domestic pollutant data (area number by household), thereby obtaining results that could reflect actual sewage treatment rates. 2. The sewer inflow coefficient 0.088, applied under the current technology guideline, provides discharge loads that fail to reflect real conditions when calculating the sewer overflow load in some territorial areas and unit watersheds. Thus, to calculate realistic discharge load, the coefficient of sewer inflow was calculated using actual surveyed data, and the load was calculated by evaluating the net rainwater inflow excluding the I/I value from the “rainfall-sewer inflow empirical formula." The coefficient of sewer inflow, calculated based on sewer flow data measured in sewer BTL projects of Jeonju City and Jeongeup City, was 0.204 for Jeonju, and 0.410 for Jeongeup, making Jeongeup double Jeonju. 3. The correlation between the calculated coefficient of sewer inflow and percentage of impervious areas was analyzed, revealing that the coefficient of determination (R2) was 0.888, suggesting a very high coefficient. Using the empirical formula, the percentage of impervious areas was calculated within the sewage treatment districts in Gunsan, Iksan, and Gimje, and the corresponding coefficient of sewer inflow was calculated as 0.248, 0.213, and 0.174, respectively. Thus, it is concerning that the load calculation may be distorted if the sewer inflow coefficient 0.088 under the current TDML technology guideline is uniformly applied, so there is a need to apply the coefficient of sewer inflow by sewage treatment district considering percentage of impervious areas. 4. It was found that as the coefficient of sewer inflow increased, the non-point discharge load increased significantly, and this increase in non-point discharge load is attributable to an increase in sewer overflow load. When the Ministry of Environment compared CSOs load and sewer inflow coefficients 0.3 and 0.31 in order to devise a plan for reducing CSOs in the Seamangeum basin, revealing that when applying 0.31, a nearly similar sewer overflow load was calculated. The sewer overflow load in Iksan and Gimje of the MOE CSOs project areas was calculated and its similarity was reviewed, and using the 2012 implementation assessment load, sewer overflow load was calculated. Likewise, since implementation assessment is based on the master plan rainfall and the sewer discharge percentage, this study used the 2012 rainfall condition and sewer discharge percentage and conducted the assessment, revealing a –2 % difference for Iksan and a +14 % difference for Gimje.
Keyword
#TMDLs Pollution sources Pollution load
※ AI-Helper는 부적절한 답변을 할 수 있습니다.