Understanding Matrix Diffusion Processes

Some key topics covered will include:

• Field methods for measuring storage in low permeability zones.
• Matrix diffusion and the chlorinated solvent life cycle.
• Implications for remedy selection, implementation, and project close out.
• How matrix diffusion might fit into current regulatory programs.
• Analytical models that are available now to simulate matrix diffusion.  
• Register today to take advantage of this important educational opportunity.

Recently, there has been an increasing realization that matrix diffusion is a major challenge for remediation of chlorinated solvent source zones and plumes. Over decades, chlorinated solvents diffuse out of more transmissive zones (e.g., sands) and are stored in low permeability materials (e.g., clays).

Once contaminant concentrations are reduced (via active remediation or natural attenuation), the diffusion gradient reverses, releasing small amounts of contaminants back into transmissive zones (i.e., back diffusion). Matrix diffusion processes have important implications for site characterization, site conceptual models, and our ability to achieve stringent groundwater remediation goals.