| To prevent groundwater contamination by viruses, the U.S. Environmental Protection Agency has regulations regarding wellhead protection zones, septic tanks, groundwater recharge, and applying sewage sludge and effluents to land. A predictive model of virus transport would be helpful in the implementation process of these regulations. Equations used to model virus transport through unsaturated media have been developed using the common assumptions that the air/water interface is an adsorbing site for virus and that a virus at the interface becomes inactivate before it can be desorbed.; This research investigates the role of the air/water interface on the overall removal of virus from unsaturated media. Objectives of the information gathered from the literature research and laboratory experiments test the following null hypotheses were false: the air/water interface is not a sorption site for MS2 bacteriophage; the air/water interface does not affect the inactivation rate of MS2 located at the interface; and MS2 located at the air/water interface cannot be desorbed from the interface.; To test the hypotheses, the following experiments were conducted on phage located at the air/water interface: active phage sampled by thin film; assaying active and inactive phage by epiflourescence microscopy; monitoring surface tension changes due to active and/or inactive phage adsorption to the air/water interface and denaturing of the phage protein coat; and desorption of active and/or inactive radiolabeled phage using the elutant BSA. In addition, a literature research was conducted on water structure, solid/solid adsorption, and protein and colloid adsorption at the air/water interface. Because there is little information on virus behavior at the air/water interface, behavior of colloids and proteins at the interface was also researched. Protein molecule behavior at the air/water interface was considered because viruses consist of a protein protective, coat, and colloid adsorption at the air/water interface was investigated because viruses are a colloid.; Conclusions of this study were: the air/water interface is a sorption site for MS2 bacteriophage; the air/water interface does affect the inactivation rate of the MS2 located at the interface; and MS2 can be desorbed from the interface. |
