A 20th century former industrial site was left fallow. Ramboll was retained to support the remediation of the site as part of the Grand Paris projects, which aim to redevelop the Paris suburbs and limit the spread of urban areas to natural or agricultural ones.
Ramboll France was commissioned by a pharmaceutical company to conduct environmental assessments (identification and delineation of the impacted areas) and drive the remediation works at one of its former sites in the Ile-de-France region.
This site was highly polluted with organic compounds (solvents), with soil impacted down to 12m, reaching the groundwater.
Remediation works were completed in 2017 and included excavation of polluted soils and treatment of these soils under shelters to avoid any health or odour impacts to the neighbourhood.
A sustainable solution
The polluted soil was mainly treated on site and reused to backfill the excavation. This technique was chosen as the most sustainable solution, limiting transport, therefore reducing traffic and CO2 emissions.
In total, more than 20,000 m3 of contaminated soil was treated onsite using mechanical mixing and the addition of lime, with more than 20,000 m3 of untreatable contaminated soil transferred to a biocentre.
Groundwater was treated at the bottom of the excavation by adding a reagent to the aquifer to achieve reduction and bioremediation in the area impacted by HVOC and oxidisation in the area impacted by HVOC and BTEX. This allowed the enhancement of the groundwater quality in the area.
The project was furthermore conducted to strict deadlines as remediation needed to be completed before the site could be sold for redevelopment. The work was performed within the agreed two-year timeframe.