Biogeochemical Processes Influencing Pb, Cu, and Fe Mobility in an AMD-Impacted Stream

This project investigated the impact of redox conditions on the mobilization of lead (Pb), copper (Cu), and iron (Fe) from sediments in Cement Creek (CC), a stream heavily impacted by acid mine drainage (AMD) in the Animas River watershed. Controlled laboratory microcosm experiments were conducted using sediments and synthetic river water (mimicking conditions from CC), subjecting them to cycles of oxic (oxygen-rich) and anoxic (oxygen-depleted) conditions, both with and without the addition of acetate to stimulate microbial activity. The study combined these experiments with advanced microscopy techniques (STEM, SEM, XRD) and analytical chemistry to assess biogeochemical processes affecting metal mobilization at the water/sediment interface.