Transport and deposition of Escherichia coli O157:H7 and Enterococcus faecalis in three Italian soils

A series of column experiments was conducted under saturated flow conditions to investigate the factors affecting Escherichia coli O157:H7 and Enterococcus faecalis transport in three Italian soils. Breakthrough curves (BTC) differed according to the bacteria species and soils. E. coli moved faster through the columns, most likely due to size exclusion phenomena, which constrained the cells to more conductive flow domains and large pore networks. Macroporosity seems to be a key factor for identifying the vulnerability of groundwater resources to microbiological contamination.