This project attempted to investigate spatial and temporal distributions of water pollution sources and their impacts on the quality of river water and sediment. Seasonal stratified water and sediment samples were collected from multiple sites at the Sincheng River in Yilan County. Source profiles were obtained from sampling and analysis of industrial waste water. Source contributions to river water and sediment were estimated by statistical and modeling analysis. The works of this project were summarized as follows: (1) Literature review: analytical results of pollutants in river water and sediment, water pollution source profile, and application of source apportionment models were reviewed and summarized; (2) Sampling and analysis of industrial waste water: a total of 30 samples from 7 industries and 2 sewage treatment plants were sampled and analyzed; (3) Characterization of industrial waste water: specific markers of industrial waste water were identified; (4) Sampling and analysis of river water and sediment: a total of 60 water samples and 30 sediment samples were collected from the upstream and downstream areas of the potential pollution sources in different seasons, followed by analyses of heavy metals and organic compounds, including dioxins and polychlorinated biphenyls (PCBs). The maximam average concentrations of metal-related pollutants in the surface water were 993.47 mg/Land 1342.11 mg/L for sulfate during the first and second sampling periods, respectively. They were 2.68 pg/L and 6.77 pg/L for Dioxin-like PCBs. The largest average concentrations of metal-related pollutants were 9205 mg/kg and 7680 mg/kg for lead in the sediments and were 153.06 pg/kg and 224.5 pg/kg for Dioxin-like PCBs at the first and second sampling periods, respectively.; (5) Spatial and temporal distributions of pollutants in river water and sediment: temporal variations of pollutants were observed at several hotspots, especially the Loung Te main ditch which was identified as the most polluted hotspot; (6) Source apportionment of river water pollutants: the percent mass accounted for measured mass (%MASS) of modeling results ranged from 31.4% to 105.7% during the two monitoring periods. Potential sources of pollutants, including heavy metals, dioxins, and PCBs, and their possible locations were estimated for follow-up investigation; (7) Source apportionment of river sediment pollutants: potential sources of heavy metals were not well identified, indicating the need of improvement of source apportionment techniques; (8) Drafting a guideline for source apportionment of water pollution for future application.

Industrial waste water, River water pollution, Sediment pollution, Pollution hotspot, Source apportionment