복하천 수질특성 및 오염원분석을 통한 개선방안

Analysis of the water quality characteristics of the Bokha stream showed that it had much higher biological oxygen demand (BOD), ammonia nitrogen (NH 3 -N) and total nitrogen (T-N) levels than other streams, and was influenced considerably by influxes from midstream and downstream. In the case of BOD, the nitrogenous oxygen demand (NOD) ratio by NH3-N is higher than that by organic material, and therefore, controlling the NH3-N concentration will improve the stream water quality. Pollution loads from the Jukdang stream and the Icheon sewage treatment plant account for 71% and 74% of BOD and TN, respectively. Considering that more than 90% of the flow from the Jukdang stream is discharge from an upstream large-scale semiconductor wastewater treatment facility, the quality of the effluent discharged by it and that from Icheon sewage treatment plant are clearly important factors affecting the quality of the stream water. Although the effluent from the two facilities satisfies quality standards for discharge water, it has a great influence on the Bokha stream. Therefore, the standard for discharge water when the flow level is high should be reviewed, considering the characteristics of the area and the environmental capacity of the area.