Dissertation (Ph.D.)--Auburn University, 2007. / Abstract. Vita. The research presented herein has resulted in the following publications: Radu, Tanja; Yang, Jae K.; Hilliard Jeremy H.; Barnett, Mark O.; "Transport of As (III) and As (V) in experimental subsurface systems", ACS Symposium Series 915, Advances in Arsenic Research, 2005, 91-103 Radu, Tanja; Subacz, Jonathan L.; Jonathan L.; Phillippi, John M.; Barnett, Mark O. "Effects of dissolved carbonate on arsenic adsorption and mobility" Environmental Science and Technology, 2005, 39(20), 7875-7882 Radu, Tanja; Kumar, Anjani; Clement, T. Prabhakar ; Jeppu, Gautham; Barnett, Mark O.; "Development of scalable model for predicting arsenic oxidation and adsorption at pyrolusite surfaces" Journal of Contaminant Hydrology, 2007, in press Includes bibliographic references (p.106-115).