Biologists from the Twin Cities and Green Bay Ecological Services Field Offices went to the St. Louis River Area of Concern the week of May 9 to collect sediment samples as part of a site characterization of the Munger Landing wetlands. These shoreline wetlands are located approximately 10 river miles upstream of the Duluth entry from Lake Superior and have been mostly disconnected from the river by an existing rail line and supporting levy. The fate of the rail line is currently being decided; if discontinued, there would be an opportunity to remove the levy, restoring aquatic habitat connectivity and significantly enhancing this important riverine/coastal wetland habitat. A preliminary sediment characterization revealed elevated concentrations of contaminants in a large shoal area off of the main river channel adjacent to the wetlands. The site characterization will evaluate chemical concentrations and associated risks to fish and wildlife resources through toxicity and bioaccumulation exposures, assess aquatic vegetation and benthic macroinvertebrate communities, and create a watershed assessment. The goal of the assessment is to inform and influence pending remedial decisions for the shoal area, advance a more holistic ecological vision for the area once the fate of the rail line is determined, and advance the recovery of the St. Louis River Area of Concern.
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