Question

Explain how molecular diffusion can complicate the remediation of contaminated aquifers.

Answer 1

The magnitude of effective molecular diffusion generally governs the mass transfer between floodplain and non-floodplain hydrofacies. so by increse in mass transfer the load on treatment unit is incresed which results in complication. Additionally, contaminant migration
and recovery showed significantly greater sensitivity to molecular diffusion than
to local-scale dispersion processes represented by the dispersivity coefficient, emphasi-
zing that if diffusion between hydrofacies in many alluvial aquifer
systems would not occurs the treatment system will not work effectively.