Environmental Effects of Dredging Technical Notes FACTORS AFFECTING LEACHATE QUALITY

dredged material in confined disposal facilities (CDFs). Factors evaluated include desorption kinetics, sediment concentration, and association of PCBs with soluble and colloidal organic matter. BACKGROUND: Contaminated dredged material is often placed in confined disposal facilities where movement of contaminants by leachate is an important environ-mental concern. No routinely applied laboratory testing protocol to predict leachate quality and quantity from confined dredged material disposal facilities is currently available. In 1984, the US Army Corps of Engineers (USACE) initiated confined disposal facility leachate investigations by developing a theoretical framework for prediction of leachate quality based on mass transport theory. The theoretical framework included both batch and column testing. Batch testing provides a quick, relatively easy method for determining the distribution of contaminants between dredged material and leachate, while column testing more closely approximates contaminant losses under field conditions in a CDF. Opera-tionally defined equilibrium distribution (partitioning) coefficients wer