Sediment Processing and Dewatering

Sediments will move through a pipeline from the dredge in the form of slurry to a processing area. The primary objectives of the sediment dewatering process are to maximize the removal of sediments and their attached PCBs from the dredge slurry, and to minimize the volume/weight of sediment that must eventually be disposed of in the landfill. This will be accomplished by using an efficient solids removal process that can achieve a high solids level in the dewatered material.

The dredged slurry will first be pumped through a vibrating shaker screen to remove debris, stones, large wood chips, and some gravel and sand from the slurry. This screened material will be staged on the processing pad for disposal. The screened slurry will then be fed into a tank where fine sands will be removed. After this process, the dredged slurry will be pumped into a system of filter presses. Filter presses will “squeeze” the remaining dredged slurry to remove excess water. Water removed from the dredged slurry will be sent to the on-site wastewater treatment facility. After the water is removed, the resultant sediment, now in a more solid form, can be loaded and transported off-site for disposal.

Dewatering Process	Detail of Shoreline Operations

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