Leachate Dispersion in Aquifers under Disposal Facilities

Abstract

Contaminated dredged material is often placed in confined disposal facilities (CDFs) designed and operated to control environmental impacts of the disposed sediment. A CDF is a diked enclosure having structures that retain dredged material solids. When contaminated dredged material is placed in a CDF, contaminants may be mobilized to form leachate that may be transported to the site boundaries by seepage. The purpose of this research is to examine the components of steady-state leachate attenuation in aquifers and to develop a predictive screening tool. The main factors affecting leachate transport and dilution through the saturated zone of an aquifer are evaluated to develop a guidance procedure to assist in decision making regarding the use of leachate controls in the CDF. The U.S. Environmental Protection Agencys’