Chesapeake Bay economics requires channel dredging to maximize its potential in trade. Because of environmentalists' objections, aspects of dredge spoil disposal have received much attention and have held up dredging operations. The effects of heavy metals is an important factor in these environmental concerns.

The most recent and popular method of disposal involves the dumping of a sediment slurry, via conveyor, into a contained, nearshore or onshore dumpsite. This creates piles of sediment above water, incident to the bay. This method of dumping provides a model for some basic sedimentary and geochemical principles: sorting by grain size owing to differing settling rates, and resultant sorting of metals owing to affinities of these metals to a specific grain fraction. Vertical zoning of metals with depth is also possible, due to supergene enrichment. These three processes are investigated by this project with the intention of providing information to help in structuring the long term use and development of the bay.

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