Efficient, Near-Complete Removal of DNAPL from Three-Dimensional, Heterogeneous Porous Media Using a Novel Combination of Treatment Technologies

Remediation of porous media containing an entrapped
dense nonaqueous phase liquid (DNAPL) is extremely difficult
due to the heterogeneity and three-dimensional spatial
nature of typical natural systems. A novel treatment technology
based on surfactant- and gravity-induced mobilization,
dense brine containment and collection, and a vapor-phase extraction polishing step is proposed as a means to
remediate such systems. Laboratory experiments are
performed using the suggested methodology applied to three-dimensional, heterogeneous systems, which are packed
based upon a realization from a correlated random field.
Entrapped DNAPL is effectively removed as a result of each
component of the technology. Following vapor extraction,
less than 1% of the original DNAPL mass remained in
the system. While these results are very promising, several
open issues must be resolved before this technology
can be considered mature; both the investigation of some
of these issues and a summary of remaining needs are
addressed.