Abstract: The permeability and filtration capacity of liners and capacity of a landfill site are investigated to design safe impervious liners of solid waste landfill. The permeability of the main pollutant, Cl-, of a solid waste landfill is obtained with soil column test. The capacity of the landfill site is determined by taking geological and hydrogeological properties of the site. It is shown that the water head of leachate on the impervious layer affects greatly the total amount of pollutants infiltrating to underground water. A design of impervious layers for the solid landfill is presented as an example.