Diffusion of Volatile Organic Compounds (VOCs) in landfilled wastes can lead to contamination of groundwater underneath waste containment facilities.

Diffusion takes place through the intact and installed composite liner system. Diffusion is exaggerated by a rise in temperature as is typical at the bottom of a landfill.

The geomembrane (normally HDPE) in the composite liner system is believed to be the primary barrier to contaminant transport but it has been shown in many studies that VOCs diffuse through intact geomembranes at appreciable rates depending on various factors.

This study aims to use the leakage detection system in a composite liner to extract air through the system which will remove VOCs from the collection system preventing them from contaminating the groundwater, and at the same time cooling the composite lining system as a whole.

Field tests and laboratory tests were performed on the diffusion of BTEX and chloroform through HDPE geomembranes.

Download technical paper here.