Use of multi-objective dredging for remediation of contaminated sediments: a case study of a typical heavily polluted confluence area in China

摘要: Sediments in confluence areas are typically contaminated by various pollutants that have been transported there inflowing rivers. In this study, we evaluated the pollution status of a area Lake Chaohu (China). Both nutrients and hazardous were analysed. Most sediment cores showed large variations nutrient concentrations at depths 10 to 18 cm. Positive release rates NH4 +-N PO4 3−-P detected cores. Hg Cd most typical problematic metal contaminants encountered, their contamination levels extended 20 25 cm, respectively. Polycyclic aromatic hydrocarbons (mostly acenaphthene fluorine) primary persistent organic (POPs) present sediments, frequently could be up depth 16 cm. Simulated dredging operations implemented laboratory, with 15 cm found suitable for suppression. With goal suppressing removing high-risk metals POPs, multi-objective plan was developed. This subdivides into five parts treated different depths. A demonstration dredged heavily polluted part, observed effects consistent those expected on basis plan. Such an approach might also useful other future.