At the end of January, HMVT started an in-situ remediation of a groundwater contamination with chlorinated hydrocarbons (VOH) in Montpellier. The pollutants in the groundwater is present in an area of several hectares and present at a depth between 8 and 15 meters. A total in-situ approach has been selected for the remediation. Contaminated groundwater is abstracted, suspended particles such as sand are removed by a mesh type filter. Subsequently an oxidant is added to the water. The water is than infiltrated into the soil. The selection for this approach is based on the specific geohydrology of the location, the desire to minimize the amount of groundwater to be extracted and discharged and the use of as little as possible oxidant.

For the project a total of 13 rows of extraction and infiltration wells have been installed, perpendicular to the groundwater flow. Remediation was started in the area where the highest levels of contamination are present. The remediation will from there move ‘downstream’ over the contamination.

Special mobile pump units have been designed and built to make this approach possible. Depending on the progress of the remediation, these pump units can easily be moved over the groundwater contamination. In this way we are always assured of an efficient and targeted remediation. The remediation of the entire groundwater contamination will take between 1 and 1.5 years.

More information

Please contact Paul Verhaagen.