ASSESSMENT OF SEDIMENT CONTAMINANTS FROM CERAMIC PRODUCTION: A CASE STUDY OF FARSTAVIKEN

摘要

A factory producing ceramics has discharged wastewater into a semi-enclosed water basin situated within the Stockholm archipelago. The objective of this study was to compare the discharge to the content of additional material at the bottom of the recipient. A material balance was made for dry substance, zinc, lead and cadmium. The discharge was estimated from interpolation of production figures between start year and 1968 when the discharge stopped. The additional material in the recipient was estimated as the integrated difference of yearly sedimentation rate between affected sedimentation beds and background values. The factory disposal up to 1968 was estimated to 18 000 tons of dry substance with a content of Zn and Pb of 40 and 50 tons respectively. The sediments show an additional content of dry substance of 14 000 tons, Zn 30 tons, Pb 25 tons and Cd 500 kg. Concentration intervals were for Zn 150 - 2 500 mg/kg for Pb 50 - 2 000 mg/kg and for Cd 2 - 60 mg/kg. It can be concluded that a material balance gives the order of magnitude and distribution of disposed material including contaminant components, even for a historical discharge.