THE SEGREGATION OF METALS DURING THE OCEAN DUMPING OF SLUDGE

The differences in the geochemical metal partitioning between the fast and slower settling flocs, formed after the dumping of sludges into the sea, were investigated in the laboratory in a simulation experiment. The fast settling flocs represented the greater mass of the flocs formed, and carried most of the metals in the oxidizable phase (organic matter and sulfides). These flocs reach the bottom near the dumping site, and their metals are in a form which may be available to the marine organisms of the area. The slower settling microflocs contain most of their metals in the reducible phase (mostly iron hydrous oxides), and they are transported greater distances from the dumping site by the prevailing currents.