Gauges help monitor the application of potassium permanganate into injection wells.
tubing and rotosonic drilling techniques to map the vertical and horizontal extent of the contamination, resulting in significant cost savings for the project.
Ayres Associates prepared a three-dimensional groundwater flow model to evaluate vertical and horizontal flow at the site. Reverse particle tracking was used to determine the origin of contamination sources and evaluate the time of travel. Treatability studies were performed to evaluate chemical-oxidation and reduction-chlorination treatment technologies.
Treating the Contamination
Results of the treatability studies showed that in-situ chemical oxidation using potassium permanganate was the most cost-effective alternative. After the potassium permanganate was mixed, it was pumped directly into the ground through injection wells.
Drews, the WDNR project manager, said this type of treatment was unusual.“ The reason this method was selected was the contamination was significantly deeper than what you would see at a normal site,” he said.“ It was down to about 200 feet. Most sites are less than 40 or 50 feet.
“ Hopefully, the process used to remediate the property will migrate down gradient of the targeted source area and take care of additional contamination that has migrated away from the site. The initial results are very good.” Some portions of the groundwater have shown more than a 99 % reduction in CVOC concentrations.
Before the use of this treatment technology, there was skepticism that such high levels of chlorinated compounds in groundwater could be successfully remediated. Cleanup efforts were completed in spring 2012.“ There needs to be more long-term monitoring,” Drews said,“ but so far we are pleased with the results. Ayres Associates did a good job of selecting and designing remedial options for this site.”
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