Several months ago Enviro-Equipment, Inc. (EEI) announced that they had been selected to build the patent-pending CleanInject carbon based injectates technology in mobile trailers and that the CleanInject system had been used on a test injection site in South Carolina later in the year.
By November 2012, the lab results from the South Carolina injection site were back and EEI announced that the pilot test that was performed in South Carolina had been a huge success. The powdered activated carbon (PAC) used in South Carolina was GR-320-IRC which is a specific gradation of carbon with no additives that can be easily mixed into a slurry and injected with the CleanInject system. The GR-320-IRC was provided by Geologic Restoration, PLLC of Charlotte North Carolina.
The site was originally proposed to be a sparge \ vent site with the remediation work being performed by Midlands Environmental of Lexington, South Carolina. After hearing about the CleanInject process, Midlands decided to pilot test the technology to see what kind of results they could get. The site was a typical coastal plain formation with a mix of silty sands and sandy silts and a shallow unconfined aquifer. The plume (dissolved gasoline) was concentrated around the tank and fuel islands with some movement down gradient. About 12000 lbs. or GR-320-IRC was injected around the former tank pit and fuel islands. The site monitoring wells were sampled about 90 days later and the analytical result indicated an 86% reduction in contaminants of concern (COC’s). Midlands has decided to wait an additional 90 days to see what additional reductions may result before taking any further action.
Similar results were recently reported by a Colorado consulting company that injected GR-320-IRC at a site that had been being cleaned up using multiple technologies over the past 20 years. The CleanInject mixing and injection process was used there as well. The analytical results from that site indicated all COC’s were below detection limits. As with all new processes this one will not be applicable to all types of sites.
From early results it appears to work well in coastal settings without a lot of clay and in original silty soils weathered in-place from sedimentary rock where a substantial soil profile is present. I looked forward to seeing results from sites in the Piedmont of the Carolinas in residual soils from crystalline rock.
Brian E Chew Sr. P.G.
Principal Hydrogeologist
