ANALYZING THE SPATIAL DISTRIBUTION OF SEDIMENT CONTAMINATION IN THE LOWER GREAT LAKES

Despite significant reductions in contaminant concentrations over the past 30 years, large areas within Lake Erie and Lake Ontario still exceed Canadian sediment quality guidelines. Hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs), lead (Pb) and mercury (Hg) can persist for long periods of rime in the environment and cause significant ecosystem dallage. Analyses of the spatial distribution of these contaminants were carried out using a GIS-based kriging technique. Initially, statistically valid results were obtained for three of four contaminants in Lake Erie (HCB, Pb, Hg) and two of four (HCB, Hg) in Lake Ontario.