Landfill liner

An elongate landfill liner for protecting an area of soil, said landfill liner being unitarily extruded from a thermoplastic material and including opposed parallel longitudinally extending side edges, the landfill liner comprising a central support having opposed top and bottom surfaces defining a substantially uniform thickness for the central support, a plurality of soil gripping protrusions having points projecting unitarily from the bottom surface of the central support, the soil gripping protrusions at any longitudinal position along said elongate landfill liner being laterally offset from the soil gripping protrusions at longitudinal positions substantially adjacent thereto for preventing furrowing of soil to which the landfill liner is applied, the central support being substantially free of soil gripping protrusions along regions adjacent the side edges of the landfill liner, a plurality of supporting protrusions projecting unitarily from the top surface of the central support and having flat supporting surfaces spaced from and generally parallel to the central support, the central support being substantially free of supporting protrusions along regions extending adjacent the side edges of the landfill liner, whereby the soil gripping protrusions enable the liner to grippingly engage soil to be protected by the liner, whereby the regions of the central support adjacent the edges that are free of the respective supporting protrusions and soil gripping protrusions enable edge regions of the central support to be secured in face-to-face contact with edge regions of a central support of a second landfill liners, and whereby the supporting protrusions enable support of a top liner in spaced relationship to the central support of the landfill liner.