PCB in water and sediment of a lake after remediation of contaminated sediment

PCB concentration in river water at the outlet of. a lake was monitored far two years following the completed remediation of the PCB contaminated sedi ment of the lake. The remediation resulted in lowered PCB concentration in the sediment, from 5 mu g g(-1) (d.w.) to 0.060 mu g g(-1) (d.w.). PCB conc entration in the water decreased over the two years, but varied seasonally. Highest PCB concentrations were recorded in summer. PCB concentration was positively correlated to temperature. Spring and winter values of PCB conce ntration were positively correlated to water discharge and to suspended mat ter probably originating from resedimented particles during remediation, PC A analysis oi congener patterns in the water supported this conclusion. The seasonality in PCB concentration and congener distribution seemed to gradu ally become similar to a location upstream of the contaminated lake.