Abstract: A method for treating materials dredged from a waterway, such as a harbor or channel, and forming a mixture suitable for beneficial re-use as structural fill. The dredged materials (28) may be placed in a treatment vessel (26) which transports the dredged materials (28) through a plurality of processing stages including a dewatering stage, a debris removal stage, a fixation, stabilization and solidification stage, a curing stage, and an offloading stage. The fixation, stabilization and solidification stage involves adding a cement type additive such as Portland Cement along with other additives which stabilize the dredged materials by chemical fixation and solidification to form the structural fill.