A landfill is an engineered facility for disposing of solid waste that cannot be recycled or composted. Modern landfills are carefully designed with protective liners to prevent contamination of groundwater, systems to collect and treat leachate (liquid that drains through waste), and equipment to capture methane gas produced by decomposing materials. Municipalities typically operate or contract for landfill services, with strict provincial regulations governing design, operation, and eventual closure. Landfill capacity is a significant concern for many communities, driving efforts to reduce waste, increase recycling, and extend landfill life. Closed landfills require long-term monitoring and maintenance.