Abstract. A detailed study on atmospheric mercury emissions from municipal solid waste (MSW) landfills in China is necessary to understand mercury behavior in this source category, simply because China disposes of bulk MSW by landfilling and a large quantity of mercury enters into landfills. Between 2003 and 2006, mercury airborne emissions through different pathways, as well as mercury speciation in landfill gas (LFG) were measured at 5 MSW landfills in Guiyang and Wuhan, China. The results showed that mercury content in the substrate fundamentally affected the magnitude of mercury emissions, resulting in the highest emission rate (as high as 57 651 ng Hg m−2 h−1) at the working face and in un-covered waste areas, and the lowest measured at soil covers and vegetation areas (less than 20 ng Hg m−2 h−1). Meteorological parameters, especially solar radiation, influenced the diurnal pattern of mercury surface-air emissions. Total gaseous mercury (TGM) in LFG varied from 2.0 to 1406.0 ng m−3, monomethyl mercury (MMHg) and dimethyl mercury (DMHg) in LFG averaged at 1.93 and 9.21 ng m−3, and accounted for 0.51% and 1.79% of the TGM in the LFG, respectively. Total mercury emitted from the five landfills ranged from 17 to 3285 g yr−1, with the highest from the working face, then soil covering, and finally the vent pipes.
Emissions of air-borne mercury from five municipal solid waste landfills in Guiyang and Wuhan, China
