SITE: Ex stabilimento Lennox Torreglia
The site being remediated presented a subsoil contamination linked to the presence of Tetrachloroethylene and its decomposition products (Trichloroethane, 1,2-Dichloroethane, Vinyl Chloride).
In highly silty soils such as the one in question, the pollutants are trapped in the soil matrix and a simple SVE vapour extraction system would not ensure the achievement of the remediation objectives; hence its application is accompanied by a system of soil heating designed and installed by the Canadian company McMillan-McGee, which allows volatilizing the pollutants present (the boiling point of which is around 60°C) so they can be easily captured by the extraction and treatment system supplied by us.
This system, called ET-DSP™ (Electro Thermal Dynamic Stripping Process) and patented by McMillan-McGee Corporation, consists of a mesh of electrodes installed in the subsoil which induces electric current and thanks to the electrical resistivity of the ground results in the transformation of the energy supplied as thermal energy. Through the injection of water, the electrical conductivity of the soil is maintained and a convective heat flow is generated that facilitates the mobilization of pollutants.
Remediation is characterized by very short operating times: within 20 weeks it is expected to bring all the soil concerned to uniform temperature (about 88°C), volatilize all pollutants trapped in the soil matrix and extract / treat them, and return the soil to normal temperature.