Aquatic sediments

Sediment traps were deployed at five sites in Lake Superior at multiple depths during lake stratification in 1987 and 1991. Mass, organic carbon, polychlorinated biphenyl (PCB), and polycyclic aromatic hydrocarbon fluxes were determined. PCB concentrations on setting solids declined from 1984 to 1991 with a first-order rate constant of 0.26 yr-1 similar to reported water column concentration decreases. No consistent temporal trends were observed in polycyclic aromatic hydrocarbon concentrations on setting particle from 1984-1991. Water of flooded, abandoned, open-cast pits in the Lusatia region in east is characterized by a high acidity, low pH, and low concentrations of dissolved phosphorus and carbon.