Filed campaigns were undertaken in Nantou County of Central Taiwan to understand the source and characteristics of dioxin concentration. The study region is surrounded by Taichung City on its western side and Central Mountain range on its eastern side. Thus this study region receives and accumulates major portion of dioxin from its western sources facilitated by air parcels. This study analyses the impact range and dioxin characters near incinerators through field measurement and GTx modeling. The measured average dioxin concentrations in Caotun, Chushan, Nangang industrial park, Jiji and Huisun were 0.0560、0.0554、0.2176、0.0454、0.0277 and 0.0067 pg I-TEQ/m3, respectively. The model output shows that Caotun station was not only affected by incinerators and traffic sources, but also impacted by secondary copper smelter and secondary aluminum plants. The Nangang industrial park may be affected by local main industrial and traffic sources. For Chushan station, the main sources were incinerators, electric arc furnaces, secondary metallurgical smelters, diesel-fueled vehicles and unleaded gas-fueled vehicles. However, it is observed that at Puli station, the dioxin concentration fluctuates with seasons. This may due to changes in land use and local wind directions and the major dioxin sources may be incinerators and traffic sources. The model output shows that pollutants are easily transferred into Chushan in north and north east wind system. Therefore, the north wind system could play an important role in transporting dioxins into Chushan and Shuili areas.

Dioxin,Incinerator ,GTx