Contaminated sediment remediation in the Laurentian Great Lakes: an overview

Sediment contaminated with metals, persistent organic pollutants, nutrients and oxygen consuming substances can be found in many areas throughout the Great Lakes. However, the highest levels of sediment-associated contaminants and some of the worst manifestations of their resultant problems are found in the urban-industrial harbours, embayments and river mouths. Management options may include source control and natural recovery, removal and containment in a confined disposal facility or upland containment cell, removal and treatment, and in situ capping or treatment. Over the past 13 years las of January 2000), over $580 million (U.S. and Canadian dollars combined) has been spent on 38 remediation projects in 19 separate areas. Not only have substantial resources been spent on sediment remediation,. but the rate of expenditure has increased in recent years. In addition, substantially greater resources have been spent on pollution prevention and control of contaminants at their source as a prerequisite to sediment remediation. While most of the remediation has taken place as a result of regulatory actions, some has been the result of cooperative partnerships, demonstration projects and unilateral voluntary actions. In the future, cooperative agreements may be expected to play a greater role in resolving contaminated sediment problems.