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A point source for environmental pollution may be identified by the spatial association of samples collected in the vicinity of the emission source. In this study, we used a simple permutation test to explore the spatial correlations between the ambient air and soil polychlorinated dibenzo- p-dioxin/dibenzofuran (PCDD/F) congener profile concentrations and their distances to a municipal solid waste incinerator (MSWI) in northern Taiwan. Kendall's τ was applied for the correlation between the PCDD/F concentrations of a total of 9 airborne and 12 soil sampling sites and their distances to the incinerator. The results showed that the correlation was highly negatively associated for soil PCDD/Fs (τ = −0.515, p-value = 0.011) and was marginal for airborne PCDD/Fs (τ = −0.667, p-value = 0.055), conditional on the seasonal wind attributions. For the 17 individual congener profiles, most of the air and soil samples had a negative association, with 7 and 10 reaching statistical significance ( p-value < 0.05) or borderline significance ( p-value < 0.10), respectively. The permutation test provides a simple and robust statistical method for the identification of a potential pollution source from a limited sample size. Our analytical results show that dioxin emissions from the investigated MSWI had a definite environmental impact on the surrounding area. [ABSTRACT FROM AUTHOR]

Municipal solid waste (MSW) management is a major concern for highly urbanized societies. Among proposed MSW management systems, regionalization programs generally have received considerable attention. This study analyzes real-world operational data to assess different MSW management policies, especially regionalization strategies, and their impact on MSW management systems in the Taipei metropolitan area. Linear programming is also used to identify the minimum costs sustained by each policy. The linear programming results show that regionalization programs are more economical and also improve incinerator operation efficiency. Sensitivity analysis indicates that the minimum treatment requirement of incinerators is a very sensitive influence on the MSW flows distributed through the entire region. The MSW of several "sensitive" administrative districts will be allocated to different treatment facilities according to different management strategies. A list of preferential sequences of MSW treatment and disposal facilities can also be identified by the model presented in this study. The results of this study may provide a useful tool for aiding decision-making related to real-world MSW management problems. [ABSTRACT FROM AUTHOR]

Ambient particulates of PM[sub2.5] were sampled at three sites in Kaohsiung, Taiwan, during February and March 1999. In addition, resuspended PM[sub2.5] collected from traffic tunnels, paved roads, fly ash of a municipal solid waste (MSW) incinerator, and seawater was obtained. All the samples were analyzed for twenty constituents, including watersoluble ions, organic carbon (OC), elemental carbon (EC), and metallic elements. In conjunction with local source profiles and the source profiles in the model library SPECIATE EPA, the receptor model based on chemical mass balance (CMB) was then applied to determine the source contributions to ambient PM[sub2.5]. The mean concentration of ambient PM[sub2.5] was 42.69-53.68 µg/m³ for the sampling period. The abundant species in ambient PM[sub2.5] in the mass fraction for three sites were OC (12.7-14.2%), SO[sub4, sup2-] (12.8-15.1%), NO[sub3, sup-] (8.1-10.3%), NH[sub4, sup+] (6.7-7.5%), and EC (5.3-8.5%). Results of CMB modeling show that major pollution sources for ambient PM[sub2.5] are traffic exhaust (18-54%), secondary aerosols (30-41% from SO[sub4, sup2-] and NO[sub3, sup-]), and outdoor burning of agriculture wastes (13-17%). [ABSTRACT FROM AUTHOR]