Landfill liners are protective barriers used at the bottom and sides of landfills to prevent harmful substances from leaking into the surrounding soil and groundwater. Typically made from materials like high-density polyethylene or clay, these liners help contain waste and minimize environmental impact. The design of landfill liners is crucial for effective waste management. They are often part of a larger system that includes leachate collection systems and gas venting systems to manage the byproducts of decomposing waste. Proper installation and maintenance of these liners are essential for ensuring long-term safety and compliance with environmental regulations.