In situ chemical oxidation for remediating chloroethenes in fractured rock aquifers

In situ chemical oxidation, i.e. the injection of a strong oxidant such as permanganate into a contaminated aquifer, can be used to remediate secondary sources of contaminants. Secondary sources include contaminants in the sorbed or non-aqueous phases, as well as dissolved in the porewater of less permeable portions of a medium. Single well push pull tests can be used as a field test method to measure the rate and extent of oxidation reactions. The effectiveness of oxidation or other remedial technologies can be assessed by observing the rate of concentration rebound after injection of potable water. The rebound rate is a direct measure of the rate of mass transfer from the secondary source into groundwater, and hence a reduction in the mass transfer rate should be reflected in a reduced rate of concentration rebound. Development of this approach for use with single well push pull tests is an active area of research.