Transport of some chlorinated contaminants by the water, suspended sediments, and bed sediments in the St. Clair and Detroit rivers

Abstract

Measurements of water flow, sediment transport and concentrations of some chlorinated contaminants were used to calculate the transport of contaminants in the St. Clair and Detroit Rivers. The transport was distributed between the water phase, the suspended sediments, and the bed sediments. The chemicals chosen were hexachlorobenzene, octachlorostyrene and polychlorinated biphenyls. From measurements on three transects in the St. Clair River and two transects in the Detroit River, it can be concluded that the suspended sediments can often transport the largest amount of contaminants, especially near sources of industrial discharge. The amount transported in the soluble phase was of the same order of magnitude as that in the particulate phase. The transport by the bed sediments was negligible in the St. Clair River mainly because of a lack of supply of such sediments. The partitioning of several halogenated compounds between the “dissolved” and “suspended sediment” phase is also discussed.