UTILIZATION OF ENABLING TECHNOLOGIES SUCH AS HYDRAULIC FRACTURING TO ENHANCE THE PERMEATION/DISPERSAL OF PERMANGANATE DURING IN SITU CHEMICAL OXIDATION

Chlorinated solvents are the largest group of compounds on the U.S. Environmental Protection Agencies (US EPA) priority pollutant list. Conventional technologies such as pump-and-treat have been relatively ineffective at remediating sites contaminated with chlorinated solvents. However, more innovative technologies such as in situ chemical oxidation (ISCO) with permanganate have shown great promise. In situ chemical oxidation is based on the delivery of chemical oxidant to contaminated media in order to impart some beneficial. Usually the desired effect is a reduction in the mass, mobility, and/or toxicity of the contaminant(s). In situ chemical oxidation is generally considered a permeation dispersal technology (i.e., the oxidant is delivered to and migrates throughout the subsurface). As such, several methods of delivery are available including: vertical and horizontal well injection, direct-push injection, vertical and horizontal well recirculation, and soil mixing. Of course, there are advantages and disadvantages associated with each delivery method and, as such, one method may be better suited for the remediation of a particular site than another. As with any in situ technology, a major challenge is overcoming the site-specific transport limitations such as heterogeneity and low permeability media (LPM). Enabling technologies, such as hydraulic fracturing, can be used to enhance permeation/dispersal of the oxidant thereby optimizing oxidant/contaminant contact. Hydraulic fracturing can also facilitate the delivery of a significant mass of oxidant (several thousand pounds) to the subsurface providing a long-term oxidant residual capable of diffusing into the soil matrix.