Experimental study on a dynamic contaminant release into overlying water-body across sediment-water interface

The dynamic release process from the contaminated sediments into the overlying water-body was experimentally investigated in an open channel flume under different hydrodynamic conditions. The time-dependent concentration variation and relative significance of the static release due to diffusive transport and the dynamic release due to resuspension/settling of the sediments were determined based on the obtained data. The experimental results indicate that before reaching an equilibrium stage, the dynamic release caused by the resuspension/settling of the sediments is much more effective than the static release by the molecular diffusion in an initial release stage. The impacts of the static and dynamic release on the overlying water column are further analyzed under different flow velocity and water depth conditions.