How does a CSE excavate sediments with reduced sediment migration?
By establishing a dry environment in which to dredge (as described above), the layer of sediment excavated from the bottom with the bucket is prevented from mixing with the water column. As a result, less turbulence is produced during the excavation, resulting in less sediment migration. In addition, after the bucket completes a dig and is retracted into the housing (as described above), as the CSE is being raised a reduction in pneumatic pressure inside the housing, can further be used to induce a “low pressure” zone that draws water and dispersed particulates, in the vicinity of the bucket, into the housing. As the CSE clears the bottom, the single-hinged door is closed and excess water collected is pumped to the surface for treatment.
