The Deûle canal is one of the most polluted canals in northern France. It contains large volumes of polluted
sediments. These have to be dredged and characterized before deciding about the technology suitable for their treatment.
The sediments are thus subjected to a physico-chemical characterization comprising particle size classification and heavy
metals sequential extraction studies. The total metallic concentrations exceed the French standards for several metals such
as cadmium, zinc, lead or copper. On average, 92% of the total weight of each metal are present in the particles that are
less than 53 µm in size. These particles represent about 85% of the suspended matter dry weight. The sequential extraction
study reveals that most of the studied metals are strongly linked to the sediments because of their association with the sulfides
and with the organic matter.