How do landfill cover requirements affect LFG energy projects?
While landfills with only intermediate or daily soil covers can achieve high collection efficiencies and tend to have higher methane oxidation rates, final cover installation lowers fugitive emissions and helps improve collection efficiency and the methane quantity in collected gas. The benefits in terms of decreased efforts needed for a landfill to remain in compliance with the NSPS can be significant. The increases in collection efficiency will likely offset decreases in LFG generation resulting from decreased waste moisture following the installation of a final cover. For these reasons, a final cover helps a landfill with NSPS compliance without significantly impacting its ability to collect sufficient quantities of LFG to support an LFG energy project. However, if a landfill is subject to the NSPS, it is required to meet surface (fugitive) emission requirements regardless of the cover type.
