R2 PM Evaluating Short- and Long- Term Effectiveness In Sediment Remediation
Thursday, 17 November 2005: 1:50 PM - 5:30 PM in Ballroom 2

(MAG-1117-832542) Risk Assessment and Remedy Evaluation at Sites in North America.

Magar, V¹, Wenning, R¹, Sorensen, Mary², ¹ Environ International Corporation, Chicago, IL, USA² Environ Atlanta

ABSTRACT- Human health and ecological risks are important considerations when evaluating and comparing different sediment remedy alternatives and implementing a remediation project. In waterways, remediation risks often include the destruction of aquatic habitats (primarily benthic communities), both short- and long- term effects from leaving contaminants in place and the transport of bed load or suspended contaminated sediments. Because of the dynamic nature of sediment cleanup projects, ranking the diverse risks and benefits of various sediment remediation strategies is increasingly included in engineering feasibility studies so that comparisons can be made among different remedy options using the same criteria and baseline information. Two types of risk evaluation are needed prior to environmental cleanup. The evaluation of remedy implementation risks addresses short-term engineering issues such as worker and community safety, equipment failures and accidents. The evaluation of residual risks addresses longer-term biological and environmental issues such as ecological recovery, bioaccumulation and the relative change in exposure and risks to humans, aquatic biota and wildlife. The potential risks of different remedies, particularly excavation, capping and both in-situ and ex-situ treatment processes, are often evaluated and included in remedial decision-making at sediment sites in North America. There is growing recognition among sediment managers that if the impacts predicted by a remedial action will cause more environmental harm than good, then the remedy option should not be implemented.

Key words: sediment, risk of remedy