A landfill is a site where waste is buried and compacted. It is not a dump. Modern landfills are engineered. They have liners to prevent leakage, drainage systems to collect liquids, and covers to keep out rain. Waste is spread in layers, compacted by heavy machinery, and covered with soil at the end of each day.

Landfills generate gas. Bacteria decompose organic waste without oxygen and produce methane, a potent greenhouse gas. Many landfills capture this gas and burn it for electricity or flare it off. Some pipe the methane to nearby homes or businesses. Without capture, methane escapes and contributes to warming.

The space problem is real. Cities run out of landfill capacity. New sites face local opposition. Recycling and composting reduce the volume, but not enough. Some countries incinerate waste to generate power, which reduces volume but creates air pollution concerns. Landfills remain the final destination for most waste worldwide.

Key features

• Liners and drainage
• Daily cover
• Methane capture
• Leachate collection
• Closure and monitoring