A laboratory evaluation of trace element mobility from flooding and nutrient loading of Coeur d'Alene River sediments

The main stem and south fork of the Coeur d'Alene River, Idaho, are contaminated with heavy metals from many years of mining. Contaminants in undisturbed sediments are subjected to selective extraction to assess the potential impacts of flooding on water quality in the river system, and their rates of release measured in laboratory flooding experiments. To simulate flooding, 18 columns are constructed and subjected to four types of treatments. Heavy metal loading of waters in the river system occurs as a result of resuspension of particulate matter, but also as a result of transformations that are either directly or indirectly mediated by sediments microbiota.