Accelerated Leaching of Fine Saline Dredged Material

The Port of Brisbane is dredged regularly to maintain navigation depths. Most of the dredged material is fine, and is placed in shallow lakes called bunds to settle. The resulting material resembles a saline grease. As part of an program to find alternative uses for this material, about 100m3 has been mixed with green waste from Brisbane City's waste stream and placed in windrows. It is hoped that the rain will leach the material sufficiently for it to compost. The green waste provides mechanical strength, increases the permeability and provides the organic matter necessary for composting action. This experiment was constructed in March 1998. So far only the surface 500mm has leached and there has been very little composting.