Washoff Characteristics of Non-point Source pollutants and Estimation of Unit Loads in Suburban Industrial Complex Areas Runoff

The characteristics of stormwater runoff and estimation of unit loads were examined in suburban industrial complex areas. During rainfall event, the peak concentrations occurred within the first 100 minutes after rainfall and then the highest concentration of NPS pollutants sharply decreased, showing strong first flush effect in suburban industrial complex. The cumulative load curves for NPS pollutants showed above the straight line, indicating that first flush effect occurred in suburban industrial complex. While the mean TSS, BOD, COD, TN and TP EMCs values were shown the highest values as 120.6 mg/L, 20.8 mg/L, 44.0 mg/L, 5.58 mg/L and 1.46 mg/L respectively. Unit loads estimated from the EMCs were TSS , COD , BOD , T-N , T-P , and Pb . Results of unit loads were compared with the unit pollutant loads from land-use in Korea and USA. The unit load of TSS was lower than that of USA. Estimated BOD and T-N and T-P unit loads were lower than that of Korea.