Environmental Effects of Dredging. Engineering Considerations for Capping Subaqueous Dredged Material Deposits -- Background and Preliminary Planning.

摘要

In recent years, the search for alternatives to expensive and limited upland containment areas for contaminated sediment has centered on in-water capped disposal. This interest was further reinforced when the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter (the London Dumping Convention) accepted the capping concept, subject to monitoring, as an appropriate technology for rapidly rendering harmless the contaminants of concern in dredged material. Subsequent detailed investigations (e.g., Brannon et al. 1985, O'Connor and O'Connor 1983) have confirmed that capping can be effective in chemically and biologically isolating contaminated dredged material from the overlying aquatic environment. However, in order to ensure this effectiveness, capping projects cannot be treated simply as a modification of conventional disposal practices. A capping project must be thought of as an engineered structure with design and construction requirements that must be met, verified, and maintained over the design life. This is not to say that traditional equipment and operational methods cannot be applied to capping contaminated materials. In fact, they have been used with good success. Technologies must, however, be applied in a systems context and with careful control and monitoring. (MM).