Microbiology of Solid Waste Landfills

A complex series of microbiological and chemical reactions begins with the burial of refuse in a landfill, and the production of methane and carbon dioxide from landfills is well documented. Methane production from landfills has several important ramifications. This chapter describes the microbiological and chemical reactions involved in refuse decomposition in landfills and the relationship of the reactions to other aspects of landfills such as gas production and leachate composition. It reviews research on the anaerobic microorganisms involved in refuse decomposition. Landfills represent a tremendous challenge for microbiological research as their size, contents, and heterogeneity require the use of novel methods for sample recovery and analysis. The lowermost component of a landfill is the liner system which includes layers to minimize the migration of leachate to the groundwater, and collect leachate for treatment. The decomposition of municipal solid waste to methane in sanitary landfills is a microbially mediated process that requires the coordinated activity of several trophic groups of bacteria.