ABSTRACT
Soils (loams, clays, and clayey soils), soil cements, and crushed limestone remain as prime natural barrier or liner materials that can effectively influence retention of many pollutants of aqueous waste streams and leachates. The design of the liner and its thickness not only depend on the properties of the soil, but also the specific site. The attenuation of the metals naturally separate into cations and anions. The hydrous oxides exert an increasing attenuation effect on the anions relative to soil texture as compared with the cations. Compaction of the soil for liner purposes accomplishes main aim for pollutant retention, namely, reduction in permeability. Compaction to the desired density or permeability is one of the real advantages of the clay in soils. The object of sealants is to reduce the permeability of natural compacted soil by application of a variety of chemicals and latexes. The behavior of municipal solid waste leachates in soil is beyond complete chemical, physical, and biological identification.
