enter the aquatic food chain, thus contaminating aquatic organisms, including fish, and ultimately placing humans and wildlife at risk of adverse health effects from consumption of these organisms. Acknowledging the human health risks posed by exposure to PCBs at many contaminated sites, some state health and environmental agencies have issued fish and wildlife consumption advisories to caution sport fishers and hunters and their families against eating the fish or wildlife from these sites. The risks of PCB-contaminated sediments, however, extend beyond direct health effects to humans and wildlife. For example, the establishment of fish and wildlife advisories might result in economic hardship for people who rely on the consumption of fish and in erosion of culture for native communities that have a fishing tradition. The presence of contaminated sediments might curtail the recreational use of the body of water for swimming or fishing or lead to restrictions on maintenance dredging, thereby potentially affecting water-borne transportation.

In recent years, substantial progress has been made in the scientific understanding of the dynamics of PCBs in the environment and the effects of PCBs on humans and ecosystems. However, important issues remain regarding the overall risks of PCB-contaminated sediments and the management strategies best suited to reduce them.

Effective management of PCB-contaminated sediments is often challenging. Many PCB-contaminated sediment sites are large, measured in acres or miles—or in tons of sediment. The sheer volume and mass of PCB-contaminated sediments at these sites makes the application of any remediation option a difficult task. The implementation of a comprehensive risk-management strategy is even more complex. Management of these sites is further complicated by the fact that many of the sediments also contain other chemicals of concern, including polycyclic aromatic hydrocarbons, metals, and pesticides. The time required to design and implement a management strategy and to evaluate its effectiveness might reasonably range from years to decades. Thus far, management strategies have been evaluated fully at only a few contaminated sites. Some but not all of these contaminated sites have been designated as Superfund sites under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980.

THE COMMITTEE’S TASK

In an effort to address these complexities and to understand the risks associated with the management of PCB-contaminated sediments, the U.S. Congress directed EPA to “enter into an arrangement with the National



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