Results Biorestoration of a Subsoil on an Industrial Site

The applicability of biorestoration in combination with groundwater extraction and soil venting was tested on practical scale on an industrial site contaminated with aromatic hydrocarbons and mineral oil. To promote in situ biodegradation an unsaturated zone was created in the sandy layer underneath the most contaminated clay-layer. The unsaturated zone was effectively aerated through soil venting. The several processes infiltration, leaching, aeration and biodegradation were monitored in the subsoil in three distinguished zones. The biorestoration capacity was quantified using the results of the monitoring program. Selecting the appropriate techniques is strongly related to subsoil conditions. For this site the combination of groundwater extracting, soil aeration through venting and biorestoration is a promising technique. Furthermore a comparison has been made for two groundwater treatment systems: stripping tower and biorotor.