Hazardous wastes can be controlled through the installation of liner materials in a solid waste landfill. The application of liner materials will prevent the migration of toxic and hazardous chemicals into surface and ground waters. Both natural and synthetic materials can be used as liners. War and Jackson (1978) investigated the landfill sites that have been in operation for more than six years and concluded that the most common liners for containment of chemical and hazardous wastes are Hypalon, ethylene propylene diene monomer, and clay. Polychlorinated biphenyls (PCBs) are aromatic chlorinated organic compounds and known as one of the most stable groups of manmade chemicals. They have low vapor pressure, low water solubility high stability at high temperature, and strong resistance to acids, alkalies, and corrosive chemicals. These physical and chemical stabilities make PCBs attractive for industrial use and also facilitate the wide dispersion and persistence of PCBs in the environment. PCBs can accumulate in food chains and have adverse effects on animals and humans. According to the classification defined under the Resource Conservation and Recovery Act (RCRA) of 1976, PCB wastes are toxic, mutagenic, carcinogenic, and bioaccumulative substances and are classified as hazardous wastes. Since PCBs are hydrophobic, the use of earth materials as liners to prevent the leaching of PCB wastes to the ground water appears feasible in landfill application. On the basis of adsorbability and desorbability of PCBs by earth materials, this paper provides an overview on the use of earth materials as liners for PCB waste disposal.