DREDGING AND DREDGED MATERIAL DISPOSAL TECHNIQUES FOR CONTAMINATED SEDIMENTS

Abstract

ABSTRACT Significant advances have been made in recent years on dredging equipment, operating techniques, and disposal methods for contaminated sediments. Preliminary guidance is available for selecting dredges and operational techniques to minimize resuspension of contaminated sediments during dredging. This is important since research results have indicated that most contaminants are attached to the clay-sized particles and natural organic solids found in lakes. Detailed guidance is available for designing dredged material containment areas based on the settling and physical properties of sediments. A modified elutriate test has been developed to predict levels of both dissolved and particulate associated contaminants in containment area effluents. This test can be used to determine the need for effluent treatment. Guidelines are available for designing treatment systems to clarify the effluent from containment areas. This paper provides information on selecting dredging equipment and operational techniques to minimize sediment resuspension, design of containment facilities, and chemical treatment of containment area effluent to improve suspended solids removal.