Large groundwater contaminations with CAHs are mainly caused by the metal processing industry and by dry cleaners’ activities. As mentioned before, CAHs are difficult and expensive to remediate by traditional remediation techniques. Because of the chemical characteristics and the number and extent of with CAH contaminated sites, they are considered by Flemish and European authorities as a priority pollutant for remediation.
The added value of the project to the EU is the following: At this moment: it is very difficult to achieve a common strategy and approval concerning regulations on soil and groundwater pollution for all countries because of the large financial implications of legislation because of the cost of remediation activities. Since large CAH contaminations represent an important part of the total remediation cost, the development of a cost efficient remediation technique could help decrease the caution of the member states towards remediation activities. Therefore, when the demonstration project for bioaugmentation succeeds, it could result in a more positive attitude of the European countries towards a common strategy on soil and groundwater remediation.
Another major advantage is the fact that bioaugmentation can be used for those cases where ENA does not suffice (approx. 25-30% of all CAH remediations). However, for large contaminations, ENA is the only economical and environmentally feasible remediation option (traditional remediation methods are very energy-consuming, produce secondary emissions and may damage ecosystems, e.g. by decreasing groundwater levels that may damage trees).
The third advantage is the reduction in remediation cost and time. Approximately 3-5% of the present groundwater contamination in Belgium and Europe can be carried out using the technique of BA. These 3-5% represent large contaminations that are expensive to remediate. Therefore, when looking at the total remediation cost, we can say that the cost for CAH remediation activities amounts to 20-25% of the total remediation cost in Belgium and Europe. Therefore, it is very clear that using BA will decrease the total remediation cost in Europe with 10-15%.
According to OVAM, the number of contaminated sites in the dry cleaning sector amount to 250-300. 85% of these contaminated sites can be remediated by using BA.