Waste foundry sand used to cover organic waste in landfills

Waste foundry sand (WFS) is a waste generated during the molding of metal parts and primarily discarded in landfills, which generates environmental and economic impacts. Studies show that this waste presents a texture suitable for the granulometric stabilization of clayey soils, enabling its use as a cover for the daily and intermediate layers of solid waste in landfills. This study aimed to obtain the hydraulic and geotechnical behavior of landfill prototypes composed of layers of organic waste and soil + 70% WFS mixture, compared to a prototype composed of clayey soil. For this, we monitored the leachate percolation and obtained the permeability coefficient (K) of semi-undisturbed samples, extracted from the prototypes. The results indicated that the mixture of soil + 70% WFS behaved as a material of good applicability for the intermediate layers of solid waste coverage in landfill prototypes, considering the environmental and geotechnical gains from the use of a high content of waste (70% replacement of soil by WFS), not changing the parameters of permeability and leachate generation.