title: Chemical characterisation of dredged sediments in relation to their potential use in civil engineering.
abstract: During capital and/or maintenance dredging operations, large amounts of material are produced. Instead of their discharge, dredged sediments may be a valuable natural resource if not contaminated. One of the possible areas of application is civil engineering. In the present work, the environmental status of seaport dredged sediment was evaluated in order to investigate its potential applicability as a secondary raw material. Sediments were analysed for element concentrations in digested samples, aqueous extracts and fractions from sequential extraction; for fluoride, chloride and sulphate concentrations in aqueous extracts; and for tributyltin (TBT). Granulometric and mineralogical compositions were also analysed. The elemental impact was evaluated by calculation of the enrichment factors. The total element concentrations determined showed moderate contamination of the dredged sediments as was confirmed also by their moderate enrichment factors, presumably as a result of industrial and port activities. Elemental concentrations in the aqueous extract were very low and therefore do not represent any hazard for the environment. The water-soluble element concentrations were under the threshold levels set by the EU Directive on the landfill of waste, on the basis of which the applicability of dredged sediments in civil engineering is evaluated, while the content of chloride and sulphate were above the threshold levels. It was found out that due to the large amounts of sediment available, civil engineering applications such as the construction of embankments and backfilling is the most beneficial recycling solution at present.
authors.affiliation: Department of Environmental Sciences, Jožef Stefan Institute, Jamova 39, 1000, Ljubljana, Slovenia. tea.zuliani@ijs.si.
authors.forename: Tea
authors.identifier: http://orcid.org/0000-0002-8367-876X
authors.initials: T
authors.lastname: Zuliani
authors.affiliation: Slovenian National Building and Civil Engineering Institute, Dimičeva 12, 1000, Ljubljana, Slovenia.
authors.forename: Ana
authors.initials: A
authors.lastname: Mladenovič
authors.affiliation: Department of Environmental Sciences, Jožef Stefan Institute, Jamova 39, 1000, Ljubljana, Slovenia.|Jožef Stefan International Postgraduate School, Jamova 39, 1000, Ljubljana, Slovenia.
authors.forename: Janez
authors.initials: J
authors.lastname: Ščančar
authors.affiliation: Department of Environmental Sciences, Jožef Stefan Institute, Jamova 39, 1000, Ljubljana, Slovenia.|Jožef Stefan International Postgraduate School, Jamova 39, 1000, Ljubljana, Slovenia.
authors.forename: Radmila
authors.initials: R
authors.lastname: Milačič
mesh_terms: D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000032:analysis / Q000737:chemistry*; D012767:Ships; D014220:Trialkyltin Compounds / Q000032:analysis; D014873:Water Pollutants / Q000032:analysis*
chemical_list: D014220:Trialkyltin Compounds; D014873:Water Pollutants; C011559:tributyltin
keywords: Dredged marine sediment; Environmental assessment; Leaching test; Pollutants; Sequential extraction