Innovative use of compost as biocover for landfill

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One of the major environmental challenges associated with landfills is the generation of landfill gases (LFGs) - primarily methane (CH4) and carbon dioxide (CO2). Microbially -mediated methane oxidation in landfill cover systems via a subset of bacteria known as "methanotrophs" has been widely accepted as a method to counter landfill methane emissions. Methanotrophs metabolize methane as their only source of carbon and energy and are naturally found in environments where there are sufficient concentrations of CH4 and CO2 to sustain their survival, such as the upper layers of a landfill cover soil. More recently, research has focused on methods to increase landfill CH4 oxidation by selecting suitable cover materials and amendments, such as composts, that induce favourable conditions for the growth of methanotrophs. Such cover systems that exploit the landfill methane oxidation process have been termed "bio-based" or "engineered" cover systems and have the potential to further reduce CH4 emissions. The overall objective of the proposed research is to assess the efficacy of a mixture of yard and leaf waste compost and biosolids compost as biocover in oxidizing methane within a field-scale application on a closed landfill in Winnipeg. The effect of climatic factors such as precipitation, ambient temperature, and atmospheric pressure on the overall performance of the system will be evaluated in order to determine if the concept of a biological landfill cover can successfully be applied to cold climates.The proposed research will provide scientific proof that allows KGS Group to be confident of the application of the landfill biocover within a climate that is as harsh and varied as Manitoba's. The biocover can be the most effective and economical solution for capturing the methane at lower-producing or older landfills where it is not economically feasible to install a full-expanse gas collection system in Canada as well as areas with a cold climate. In addition, this research will find a sustainable solution to reuse of yard and leave waste and biosolids as landfill biocover which will not only benefit the City of Winnipeg, but other municipalities across Canada.