Smart barrier design for groundwater remediation

FRANCISCA, FRANCO M.; GLATSTEIN, DANIEL A.; CARRO PÉREZ, MAGALÍ E.

Toronto

Conferencia; 2011 Pan-Am CGS Geotechinical Conference; 2011

Contaminant transport in non-reactive porous media depends on soil and pore fluid properties. In the case of fine soils, chemical reactions, electrostatic interactions and biomediated reactions can modify the physical properties of the porous media. This work evaluates mass transport through reactive barriers, showing the relative importance of particle-fluid interactions and microorganism growth on contaminants displacement. Compacted soils samples were tested with arsenic solutions and landfill leachate as permeating liquids. The addition of clay decreased the hydraulic conductivity and delayed the contaminant displacement due to electrostatic attraction between the charged soil particles and counter ions. Microorganisms were responsible for pore clogging due to the increase of biomass with permeation time. These two effects were simultaneously considered by implementing a 1D-mass transport equation to simulate the behaviour of reactive barriers. Obtained results are of fundamental importance for the design of ?smart? barriers for the remediation of contaminated groundwater.