Permanganate Oxidation Schemes for the Remediation of Source Zone DNAPLs and Dissolved Contaminant Plumes

摘要

This study utilized a series of laboratory experiments to explore the feasibility of applying oxidation techniques to clean up ground water and soil contaminated by chlorinated ethylenes. We investigated problems that could potentially impact the oxidation of TCE with permanganate, such as MnO_2 precipitation around zones of high DNAPL saturation, and permeability-related flow bypassing. 1-D column and 2-D flow tank experiments provided data on mass removal rates and related flushing efficiencies. The results indicate that mass removal rates are greatly influenced by MnO_2 precipitation and flow bypassing. It is anticipated that in actual field settings, the issue of flushing efficiency needs to be considered in the design. A permanganate reactive barrier system (PRBS) was designed and a proof-of-concept experiment was carried out in a 2-D flow tank. Results show that the PRBS was able to delivery permanganate at a stable, constant, and controllable rate. The design works well in reducing the concentration of the TCE contaminant plume. This idea could be developed as a long-term reactive barrier for the remediation of plumes of chlorinated solvents. Installation would be relatively quick, and cost efficient. Once installed, its long-term management cost would be minimal, and it would require only sporadic recharging with permanganate.