“Your question reveals your way of thinking like so many others – that dredging harms the environment! This is old thinking,” he says. “If the polluted/ contaminated soil is not dredged/removed from the harbour basins, is the harbour in that case clean and is the environment safe?

“Dredgers don’t pollute, they only displace pollution, most of the time to a safer  and better place in view of sanitation or treatment. Dredging projects are always the subject of EIA reports and heavy monitoring of the dredging processes to keep potentially dangerous soils confined in specified areas.” Removal of polluted soil is always better than leaving it on the bottom of port basins, says Mr Vandewalle – “especially when it is exposed to involuntary, uncontrolled, unmonitored displacements such as impeller impact, storm impact, biological impact, etc., whereby flora and fauna remain exposed for an unlimited time”.

The major reluctance to dredge in ports is based on the outdated definition that dredged soil is waste and that waste should be deposited in areas especially adapted or constructed for that purpose, he says. “But the first thing a port must do is use common sense and if the dredged soil is polluted or contaminated,it should be moved to a special area either onshore or offshore where further dilution in the environment is prevented and it can await further treatment.

“Modern technology is sufficiently tested to clean and/or diminish the volume so that the pollution can be separated for depositing in safe areas. If the dredged soil is not polluted or contaminated,it is not to be treated as waste – it can be used for land reclamation or it can be dumped offshore in an approved disposal area.” Jan De Nul has its own specialist company, Envisan, for cleaning soil, areas, etc., from various pollutants. “Together with special dredging techniques, which prevent contaminated soil from spreading further in the environment during dredging,and the ability to treat such dredged soil,we offer global solutions to our clients facing such problems,”says Mr Vandewalle.