Potential solution to pollution of groundwater by diffusion of volatile organic compounds through the primary HDPE geomembrane in composite lining systems of landfills

Abstract

Waste in a landfill is exposed to the chemicals and heat generated over time, producing harmful fluids in the form of leachate or landfill gas that migrate from the landfill towards the liner or capping, and include organic contaminants. The high-density polyethylene (HDPE) geomembrane (GM) component of the landfill liner is often believed to be the primary barrier to contaminant transport, but volatile organic compounds (VOCs) diffuse through geomembranes at appreciable rates. The aim of this study was to obtain reliable data on the reduction in diffusion of VOCs through the HDPE GM component in the composite liner systems of landfills by extracting air through the leakage detection layer or drainage layer of the composite liner. It was shown that introducing a flow of air through a pervious zone adjacent to the GM layer in a landfill liner would significantly reduce the concentrations of VOCs in the groundwater beneath landfills and waste containment facilities.