Environmental characterization for sediment management: a case study of the port of Civitavecchia (Rome, Italy)

This study presents the environmental characterization of sediments from the Port of Civitavecchia (central Tyrrhenian Sea) subjected to maintenance dredging aimed at restoring original bathymetries and ensuring navigation safety. The aim was to identify sustainable management options that promote sediment reuse, while minimizing impacts on the marine ecosystem.

A multidisciplinary Weight of Evidence (WOE) approach was applied, integrating chemical and ecotoxicological lines of evidence from 78 sediment samples. Analyses were conducted for metals and trace elements and major organic contaminants. Ecotoxicological characterization was performed using a battery of three bioassays (Aliivibrio fischeri, Dunaliella tertiolecta, and Paracentrotus lividus). In addition, a site-specific Severe Effect Level (SEL) for hydrocarbons C > 12 was calculated.

Despite the detection of significant concentrations of petroleum hydrocarbons (C > 12), only a few samples exhibited a significant ecotoxicological response. Statistical elaborations demonstrated that contaminant concentrations alone were not the primary responsible of toxicity in the investigated sediments The determination of a site-specific SEL allowed the reclassification of sediments, from Class E to Class D, enabling their disposal in an impermeable confined disposal facility.

Results of this study confirm that the adoption of a WOE approach is essential to promote a sustainable management of port sediment. Moreover, the application of advanced statistical models for the determination of SEL enabled the reclassification of sediments, thereby avoiding landfill disposal. This approach supports circular economy principles while minimizing adverse impacts on the marine environment.