Transport and Survival of Pathogenic Bacteria Associated With Dairy Manure in Soil and Groundwater

Human pathogens in animal waste represent a severe health threat when the groundwater resources become contaminated as result of improper manure management practices. Currently, understanding of the fundamental mechanisms governing the fate and transport of pathogenic microorganisms associated with manure in soil and groundwater systems is still lagging despite federal regulatory efforts to boost drinking water quality and public health security through the introduction of the Ground Water Rule by the Environmental Protection Agency (EPA) in October 2006. The goal of this project is to evaluate the impact of various manure components, e.g., pH, organic matter, nutrients, particulate matter, and potential biofilm growth on the transport and survival characteristics of fecal indicators and pathogenic bacterium E. coli O157:H7. Research objectives will focus on determining the relationship between the deposition of indicator organisms E. coli and pathogenic serotype E. coli O157:H7 through well controlled laboratory column studies and examining the interactions between manure suspensions and bacterial strains and their associated transport behavior under different solution chemistry. In addition, the potential of biofilm formation as a result of various manure components and its impact on bacterial attachment and survival mechanisms will be investigated. These objectives will be achieved through a collaborative effort combining our expertise in the area of microbiology, molecular techniques and kinetic study. The results of this proposed research are expected to advance the basic understanding of mechanisms controlling the deposition and survival of fecal indicators and pathogenic bacteria, which are essential for the development and validation of predictive models for pathogen transport in soil and groundwater. The information will lead to an improvement of manure management practices, which are of interest to dairy farmers, policy makers and water professionals in the State of Wisconsin and across the country.