Sammendrag
Elkem Carbon AS and Elkem Solar AS are conducting a monitoring program in the Kristiansand fjord
near their factories. This program supplements the authorities overall monitoring and surveillance
programme in the Kristiansand fjord. In 2013, samples of the water masses, blue mussels, sediments
and ecological status of the soft bottom fauna were investigated and a risk assessment study of the
contaminated sediments was performed. No systematic changes in metal or PAH concentrations in the
water masses over the three-year monitoring period could be detected. Metal content in mussels was
generally low to slightly elevated, however PAH content in mussels was elevated. Contaminant
concentrations were high in the Elkem harbour sediments. The sediment contaminant concentrations
were used in a risk assessment. Calculations gave a transport of approx. 3 kg PAH annually from the
sediments. The directed discharges of PAH with process water is now strongly reduced to approx. 10
kg/yr. The contaminated sediments represent a calculated risk for sediment-living organisms and to
humans based on a lifelong intake of seafood from the area. The latter is not necessarily realistic since
fishing in the area hardly occurs and PAH do not accumulate in fish flesh. The quality of the benthic
fauna in the Fiskåbukta has improved significantly over the years and might have reached a status as
good as can be expected in a mulitisource, urbanized area.
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