The International Joint Commission (IJC) was established between Canada and the United States under the Boundary Water Agreement in 1909. The Great Lakes Water Quality Agreement between the two countries (signed in 1972, revised and renewed in 1978) expresses the determination of each country to restore and en­ hance the water quality of the largest freshwater system in the world. The Agreement provides for two inter­ national boards to assist the IJC: the Great Lakes Water Quality Board and the Great Lakes Science Advisory Board. In 1982, the Dredging Subcommittee of the Great Lakes Water Quality Board was asked to investigate and provide an assessment of the environmental impacts of sediment-bound contaminants and to recom­ mend alternate strategies for solving ecological problems associated with the presence and removal of pollu­ tants. This issue however, was beyond the scope of the Dredging Subcommittee. It was then referred to the Great Lakes Science Advisory Board with a specific request that the Board focus on whether contaminated sediments located in areas with water quality problems and impaired uses should be removed and if so, under what conditions. The Science Advisory Board established a Task Force to address these issues with specific reference to: - provide the IJC with an assessment of the effects of sediment-bound contaminants on biota and water quality; - recommend appropriate remedies for possible application by the parties for remedial activities in the Great Lakes; and - identify gaps in knowledge and suggest appropriate investigations to provide this knowledge.

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Introduction: Problems with In-Place Pollutants.- One: Processes Involved In Transfer and Cycling of Contaminants.- 1. The physics of sediment transport, resuspension and deposition.- 2. Sediments as a source for contaminants?.- 3. Biological processes involved in the cycling of elements between soil or sediments and the aqueous environment.- 4. Partitioning of trace metals in sediments: relationships with bioavailability.- Two: Impacts of Sediment Mediated Contaminants.- 5. Interactions between sediment contaminants and benthic organisms.- 6. Sediment-associated contaminants and liver diseases in bottom-dwelling fish.- 7. The human population - an ultimate receptor for aquatic contaminants.- Three: Methods of Assessing Bioavailability and Impact Assessment.- 8. The use of bioassay and associated tests in dredged material and disposal management.- 9. Phytoplankton bioassays for evaluating toxicity of in situ sediment contaminants.- 10. Assessing the bioaccumulation of contaminants from sediments by fish and other aquatic organisms.- 11. In-situ contaminants and environmental assessment - an ecological summary.- Four: The Social Implications and Context.- 12. Introduction. The social context: an overview.- 13. The social and human relevance of in situ sediments.- 14. Assessment of socio-economic ramifications.- 15. Perceptions, paradigms and ethics: a perspective on the social context of environmental issues.- 16. The leading question: in-situ structures of thought?.- Five: Case Studies.- 17. Accelerating recovery of the mercury-contaminated Wabigoon/English River System.- 18. Contaminated sediments in the Elbe Estuary: Ecological and economic problems for the port of Hamburg.- 19. A case study: Bay of Pozzuoli, Gulf of Naples.- 20. Consequences of environmental contamination by lead mining in Wales.- Six: Remedial Options.- 21. Sediment - associated contaminants - an overview of scientific bases for developing remedial options.- 22. A protocol for the selection of remedial options to control in situ sediment contaminants.- 23. Summary.- 24. Recommendations.