ENVIRONMENTAL RISK ASSESSMENT OF SURFACE-WATER AND SEDIMENTS IN COPENHAGEN HARBOR

The environmental risk assessment of Holmen, a former naval base, incl uded characterisation of the sediments with regard to pollution with x enobiotics, heavy metals, nutrients and bacteria, and ecotoxicity. A s imple hydraulic model was established, and the release of substances f rom the sediment to the water was assessed. Sediment biotests with Cor ophium volutator and porewater biotests with Skeletonema costatum and Acartia tonsa were conducted. The sediment was characterised as strong ly contaminated in the major parts of the investigated area. Based on the application of the acid volatile sulfide method it was concluded t hat practically none of the heavy metals were bioavailable. Both the s ediment and the porewater from a number of stations were toxic. The to xicity did not appear to be attributable to the content of heavy metal s, more likely to other contaminants. Furthermore, the sediment, which has served as a sink for accumulation of contaminants over a period o f many years, also may constitute a source of contamination due to pot ential release of heavy metals and xenobiotics from the sediment to th e water in some areas. The release appears to give rise to concentrati ons above the EU Water Quality Objectives at some stations. (C) 1998 I AWQ. Published by Elsevier Science Ltd.