Retrofitting Rapid Stabilization and Gas Collection in Older Landfills

The goal of this field test is to enhance landfill gas (LFG) production and collection at the City of Saskatoon Landfill by adding moisture to the landfill to stablize the existing waste mass. Gas wells and monitoring systems, moisture probes, gas headers, water lines, condensate traps and wellhead assemblies will be installed over a portion of the landfill during the first five months of the project. The initial testing and trial operation of the LFG extraction system will follow in the next two months. Actual testing over the next 18 months will evaluate gas flow, gas composition, moisture addition rates, moisture movement in the waste and stabilization rates. Evaluation will be done also of well spacing, well sizes and moisture addition rates on LFG production and leachate quantity and quality. A full scale LFG project will be considered if it is proven that water addition will not pose a significant increase in risk to water resources such as the South Saskatchewan River, and that gas generation rates can be increased enough to justify a collection system. Once operational, a new LFG utilization facility would have the capacity to utilize 1,800,000 m3/yr of LFG. Net emission reductions are forecast to be in the order of 12,300 tonnes/year of CO2 and 2,230 tonnes/year of methane.