Preliminary evaluation of potential occupational and public health impacts of sediment decontamination facilities for new york/new jersey harbor

摘要

Sediment is accumulating in New York/New Jersey Harbor, and shipping channels are rapidly becoming too shallow for large ships. The Port Authority of New York/New Jersey has determined that dredging of the ship channels is essential to keep them navigable. About five million cubic yards of sediment must be removed per year to keep the channels open. Without dredging, the channels will soon become unusable, and the shoreside shipping and warehousing businesses that depend on them will fade away. The economic loss to the area would be devastating. But the deeper layers of sediment in the Harbor contain a broad range of pollutants that are hazardous to humans and the environment-a legacy of past discharges that are no longer permitted. These include heavy metals, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), chlorinated pesticides, and dioxins. As a result, there are several million cubic yards of sediments to be dredged per year that do not meet applicable criteria for ocean disposal and must be dealt with in some other way. A possible solution to the problem is to treat the dredged material to immobilize or destroy the contaminants and make the treated sediments suitable for disposal in the ocean or on land at acceptable cost. A variety of technologies can be used to achieve this goal. The simplest approach is to make manufactured soil from untreated sediment. The most complex approaches involve high-temperature destruction of organic contaminants and immobilization of inorganic contaminants. When any of these technologies are used, there is potential for risks to human health from process wastes and from the treated materials themselves. Also, disposal or beneficial use of treated materials may generate other risks to human health or the environment. A description of some of the technologies considered is given in Table 1. Success in removing or immobilizing the contaminants, which varies significantly among technologies, is reported elsewhere. This report provides a preliminary evaluation, or 'screening assessment' of potential occupational, public, and environmental health risks from dredging, transporting, and treating contaminated harbor sediments with thermal treatment methods to render them suitable for disposal or beneficial use. The assessment was done in stages as the project advanced and data became available from other tasks on characteristics of sediments and treatment processes.