Track: Environmental Engineering

Abstract

In recent times, it has become crucial to protect soil, surface and groundwater reserves from pollution due to the consequential effects of landfilling operations. In a bid to safeguarding environmental and human health, various technologies have been employed in waste containment over the years. Significantly, geomembranes/ mineral composites liners have been employed. Sequential tests using a small-scale laboratory bespoke column hybrid permeameter device was conducted on the impact of infusion of pollutant species in a geocomposite lining system/ mineral barrier through a circular destructed polyethylene membrane. The imposition of pressure as a simulation for waste load on the pollutant infusion rate, pollutant transport and the buffering capability of natural-mineral soil profile were studied. Infusion through the geocomposite liner-buffering system (BS) was measured for tests with the destructed membrane under simulated waste loads of up to 150 kPa. Results and analysis showed significant reduction in infusion rate with increased pressure on the system. This reduction is attributed to the reduced barrier transmissivity, θ and soil liner compressibility alterations in the soil barrier. The infusion rate data for tests with the destructed membrane in this study were compared with predicted values from equations provided by Forchheimer and Giroud et al. The comparison showed inapplicability to this study and also showed imperfect contact conditions at the membrane/soil interface if assumed in practice. Nevertheless, equations from Giroud for good contact conditions revealed rational infusion rate predictions through the destructed membrane of the geocomposite media.