Publication:

 

Cooper, M.J., R.R. Rediske, D.G. Uzarski, and T.M. Burton. 2009. Sediment contamination and faunal communities in two subwatersheds of Mona Lake, Michigan. Journal of Environmental Quality. 38:1255-1265

 

Project Description:

A preliminary investigation of the nature and extent of sediment contamination in Little Black Creek, Cress Creek, and Mona Lake was performed that involved sediment chemistry and toxicity, ecological assessment, and metal transport modeling. Sediment chemistry and solid-phase toxicity were examined at 12 locations in Little Black Creek, 6 locations in Cress Creek, and 3 locations in Mona Lake. High levels of PAH compounds (40  60 mg/kg) were found in an area near Seaway Drive, downstream of Sherman/Getty culvert, and the stream reach between the Mona View wetlands and Airline Rd. Sediment toxicity also was observed at these locations. High levels of cadmium were found in the stream reach from Peerless Plating (1,600 mg/kg) to the creek mouth at Mona Lake (11 mg/kg). Elevated levels of chromium, lead and zinc also were present. High mortality in both test organisms was observed near Peerless Plating (0-20% survival). Based on these results, the Little Black Creek system was found to be highly impacted by metals and PAH compounds. The Peerless Plating Superfund Site appears to be the source of most of the cadmium and chromium observed in the creek, although additional sources of metals are present near the Mona View Wetlands, Seaway Drive, and the Lower Wetlands.

A physically-based model was developed in this study for simulating metal (cadmium) and sediment transport in a coupled stream-wetland system that consisted of the water column, the underlying active bed, and the adjacent wetland subsystems. The model was tested by applying it to Little Black Creek. The simulated cadmium and sediment concentrations were compared against the observed ones and good agreement was achieved. The modeling results suggested that cadmium sorbed to the stream bed sediments was the primary source of cadmium contamination in the system. Re-suspension of the cadmium contaminated bed sediments played a critical role in the cadmium fate and transport. The modeling particularly emphasized the importance of the long-term, persistent cadmium accumulation process in Mona Lake and the wetlands, and the relevant threat to the ecosystem.