Landfill cover
Material placed over waste to manage exposure, water infiltration and gas movement.
Example
A well-maintained cover can support gas collection and help control surface emissions.
The catch
Performance depends on design, condition and site management.
Related terms
Anaerobic decomposition, Anaerobic digestion, Biogas, Biomethane, Composting, Destruction efficiency
In more depth
Landfill cover, explained.
Landfill cover comes in grades, from daily soil cover to an engineered final cap, and each grade changes how much gas escapes. Daily cover is a thin layer of soil or an approved alternative spread at the end of each working day. Intermediate cover protects areas left inactive for longer. A final cap, placed when a section is full, usually combines a low-permeability layer such as compacted clay or a plastic membrane with drainage and topsoil.
A tight cap stops gas seeping out and lets the well field draw more of it, which lifts gas collection efficiency. Soil covers also host bacteria that consume part of the methane rising through them, a process called methane oxidation. Cracks from settlement, erosion or drying open shortcuts to the surface. Operators walk the site with handheld detectors to find the weak spots and repair the cover.