In-Situ Remediation of Heavy Metal–Contaminated Sediments Using the Resuspension Technique.

Heavy metal pollution in sediments and soil is an unavoidable anthropogenic issue with implications for quality of life and is a major long-term remediation challenge. This paper aimed to evaluate an in-situ remediation technique (resuspension) for sediment that may be employed in a variety of contaminated site cleanup programs. Surface sediment samples were obtained from a shallow harbor on the St. Lawrence River, in Canada in 2019. Harbor sediment from the St. Lawrence River in Quebec is anthropogenically polluted by metals. Various experiments were performed using a designed reactor to evaluate sediment resuspension remediation technology. The method is based on sediments with a higher specific surface area that adsorb more metal contaminants. Therefore, the objective was to remove this fraction by the resuspension technique. Results showed that the levels of seven metals (As, Cd, Cr, Cu, Ni, Pb, and Zn) were reduced by removing only 2.63% of the sediment. Removal efficiency values varied from 3.48% for Cd to 32.4% for Cu). The results of the sequential extraction tests imply that the resuspension technique is capable of decreasing the risk of remobilization of heavy metals in the aquatic ecosystem. Therefore, this method could potentially be used to remediate metal–contaminated sediment with minimal sediment removal. [ABSTRACT FROM AUTHOR]