Authoritative, up-to-date guide to dredging theory and practice. From selecting the right equipment, to evaluating environmental impact, to bidding on a project, Handbook of Dredging Engineering, Second Edition, is the last word on modern hydraulic dredging. Edited by John B. Herbich, with contributions by well-know experts in the field, the Handbook examines basic fluid mechanics; dredge pumps; dredging equipment; sediment; pipeline transport of solids; dredging methods; disposal and placement of dredged material; numerical models for predicting the fate of dredged material placed in open water; environmental effects of dredging activities; instrumentation and automation; and project planning. This vital new edition covers major advances made over the last seven years. Three chapters are new to this edition: numerical models for predicting the fate of dredged material...subaqueous capping of contaminated sediment...and removal of contaminated sediments by dredging, with illustrative case studies.

This technical note contains assessments of conventional and special-purpose dredges in removing sediment with minimal sediment resuspension. If sediment resuspension is a critical factor in dredging areas of contaminated material, the following guidance will aid in specifying the dredge and operating conditions. Investigations were conducted as part of the Corps of Engineers Improvement of Operations and Maintenance Techniques (IOMT) Research Program to evaluate the resuspension of sediment into the water column due to dredging operations. Laboratory, field, and literature studies have been used to define the sediment resuspension characteristics of most conventional and several special-purpose dredges. The natural hydrophobic tendency of most organic contaminants and the high sediment-sorptive capacity for inorganic contaminants limits release to the soluble forms and makes the simple measure of sediment resuspension during dredging a relative measure of the potential for contaminant release.

This technical note contains assessments of conventional and special-purpose dredges in removing sediment with minimal sediment resuspension. If sediment resuspension is a critical factor in dredging areas of contaminated material, the following guidance will aid in specifying the dredge and operating conditions. Investigations were conducted as part of the Corps of Engineers' Improvement of Operations and Maintenance Techniques (IOMT) Research Program to evaluate the resuspension of sediment into the water column due to dredging operations. Laboratory, field, and literature studies have been used to define the sediment resuspension characteristics of most conventional and several special-purpose dredges. The natural hydrophobic tendency of most organic contaminants and the high sediment-sorptive capacity for inorganic contaminants limits release to the soluble forms and makes the simple measure of sediment resuspension during dredging a relative measure of the potential for contaminant release.

Some of the nation's estuaries, lakes and other water bodies contain contaminated sediments that can adversely affect fish and wildlife and may then find their way into people's diets. Dredging is one of the few options available for attempting to clean up contaminated sediments, but it can uncover and re-suspend buried contaminants, creating additional exposures for wildlife and people. At the request of Congress, EPA asked the National Research Council (NRC) to evaluate dredging as a cleanup technique. The book finds that, based on a review of available evidence, dredging's ability to decrease environmental and health risks is still an open question. Analysis of pre-dredging and post-dredging at about 20 sites found a wide range of outcomes in terms of surface sediment concentrations of contaminants: some sites showed increases, some no change, and some decreases in concentrations. Evaluating the potential long-term benefits of dredging will require that the U.S. Environmental Protection Agency step up monitoring activities before, during and after individual cleanups to determine whether it is working there and what combinations of techniques are most effective.