The overall goal of this dissertation was to describe fecal bacteria transport through the environment.; The survival of indicator bacteria (fecal coliforms, Escherichia coli and fecal streptococci) in dairy cow manure over a range of environmental temperatures (4, 27, and 41°C) and manure moisture contents (30%, 55%, and 83%) was studied. After an initial 3–10 days growth period, the coliforms showed significant reductions in responses to temperature but not moisture content after 3 weeks or less. The streptococci showed no significant reductions after three months. Manure still could contaminate water resources after 103 days.; E. coli adsorption was investigated by comparing responses between silt loam and sand. Up to 108 of E. coli cells were sorbed per gram of the silt loam soil whereas only 104 cells attached to the same mass of sand. Both Freundlich (R2 = 0.89) and Langmuir (R2 = 0.93) isotherms described observed adsorption data well for soil but a linear isotherm did not. Results showed that E. coli adsorption to both soil and sand particles was reversible.; The effect of fine (1 mm) vs. coarse (>1 mm and 2 mm) heterogeneous sand media on breakthrough of E. coli was compared. A second-order kinetic adsorption model coupled with the convection-dispersion equation was used to describe E. coli transport through sand columns packed with those two media. Model parameters were also estimated. A total of 97% E. coli cells were recovered from the effluent of the coarse sand column whereas only 52% from that of the fine sand column. The model fitted the coarse sand better (model efficiency = 91%) than that of the fine sand (61%).; The impact of antecedent soil water content (5.3%, 72% and 99% saturation) on overall retention of E. coli in silt loam soil columns was investigated. Most tested columns (93%) had a cell removal efficiency of over 99.999%. The lowest removal efficiency (75%) and greatest E. coli cell concentration (2.7 × 107 cfu/mL) were found in the effluent from saturated columns.; Information obtained from this study can be used to assess pathogen sources when developing TMDLs.
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