The Camelot Superfund Site was the location of a former dry cleaning facility. Tetrachloroethylene, Trichloroethylene, and their degradation products contaminated the soil and groundwater at the site within dangerously close proximity to the West Fargo drinking water aquifer. ERH was selected to treat the site to a soil goal of less than 3 mg/kg PCE and a groundwater goal of 1 mg/L total VOCs.
The site posed three specific in-situ challenges:
- Extremely low permeability clays (108 cm/sec)
- Very high ground water conductivity (11,000 micro-siemens)
- A portion of the treatment zone was in the side and front yard of an occupied residence.
Current Environmental Solutions (CES), now part of Cascade Thermal, treated approximately 13,800 cubic yards of soil over a 9-month period. There were 56 different electrode and vent assemblies, along with a network of horizontal vapor extraction wells to assist with steam capture in low permeability areas. Approximately 5,188 lbs of contaminant mass was extracted. Final sampling conducted by the EPA confirmed that the remedy had reduced the groundwater concentrations by 99.98% and the soil concentrations between 99.96% and 100%. These goals were achieved with zero stray voltage, demonstrating the electrical isolation capabilities unique to Cascade Thermal/CES equipment and experience.