Evaluation of Dredged Material Disposal Options Using Chemical and Biological Testing Data and Risk Based Indices

Abstract

This paper provides an overview of the Green Book testing regime, focusing on evaluation of risk and compares the results of synoptic testing of sediments from three harbors in the Northeast. First, sediment chemical concentrations from the three locations are compared to established sediment quality guidelines (SQGs). Next, biological effects tests, including the 10-day toxicity tests using Ampelisca abdita and Americamysis bahia are conducted to determine the potential for adverse effects. Finally, 28-day bioaccumulation tests using Macoma nasuta and Nereis virens are used to assess contaminant mobility. Alone, these tests only assess exposure and not the potential for adverse effects-from COCs to higher trophic levels. For this reason, a risk-based approach is also used to evaluate the potential for ecological and human impacts from exposure to contaminated sediments. Risk-based evaluations, performed on bioaccumulation data from the 28-day tests, were conducted and the results are evaluated in the context of the standard evaluations for suitability of dredged material disposal in open waters. This risk-based approach to evaluate disposal options allows an effective management strategy, which minimizes environmental effects.