Suction, Water Retention Capacity and Permeability Assessment of Compacted and Unsaturated Cover Layer

This paper exposes characteristics from an evaluated cover layer (0.6 m height) from the experimental Muribeca landfill of Urban Solid Residues (SUR), located in Jaboatão of Guararapes, Brazil. Through laboratory experiments of suction, grain size distribution, and permeability, those parameters were analyzed based in the existing technical standard Brazilian for this procedure. The soil was studied by the division of a cover layer, after 5 years from its completion, of 0,6m, in depth the upper half (0.1 m to 0.3 m) and lower half (0.4 m to 0.6 m), looking for differences of leaching through the upper to lower part. Therefore, the consequences to be presented from the leaching of the materials, after 5 years of finalization of the landfill, making its permeability increase. Concerning its water retaining, it is the most retained in the upper part, which comprises the compost, with a difference in the order of 7 per cent the superior half to inferior half, retaining the least suction from the surface. Leaching was detected through permeability procedure of worthless difference between upper and lower part of the cover layer. Nevertheless, results revealed the efficiency of the cover layer in retaining the rainwater, offering this layer as an alternative solution for the appropriate waste disposal.