Category: Great Lakes Cleanup

A spatio-temporal study of methylmercury biogeochemistry in wetlands of the southern Lake Michigan watershed

  • Measure the levels of total mercury (Hg) and methylmercury (MeHg) in the surface waters of wetlands across the Grand Calumet region of northwestern Indiana
  • Measure the concentrations of total and MeHg in wetland sediments – the main repositories for legacy Hg contamination in these wetlands
  • Measure the concentrations of total and MeHg in porewaters of wetland sediments – the main route for MeHg transport from the sediments to the overlying waters – in the region
  • Assess the MeHg levels in fish from wetlands with permanent open water

Contamination of Wetland Sediments Indiana Dunes National Lakeshore: Implications for Wetland Restoration Strategies

  • To quantify the current environmental quality, both in terms of metal concentrations and ambient conditions (pH, Eh temperature. groundwater flow directions and velocities), in different subenvironments (defined in terms of hydrologic, ecological and disturbance histories) of the Great Marsh, Indiana Dunes National Lakeshore
  • To develop simple models/relationships to explain the spatial distribution of heavy metals across the Great Marsh and with depth within the sediments, and the environment conditions associated with enhanced mobility
  • To use these models/relationships to determine the potential for heavy metal release associated with certain changes in hydrology, hydrochemistry and sediment chemistry that may occur during and following wetland restoration at the Great Marsh