A field-scale, in-situ, slurry-phase bioremediation demonstration was conducted at the French Ltd. Superfund Site in Crosby, Texas. As part of this study, several aeration technologies were compared, based on reliability, organic chemical emissions levels, mixing, and oxygenation characteristics. An economic and technical comparison was drawn between these technologies and several high-purity oxygen-based technologies, including Praxair's (formerly, Union Carbide Industrial Gases) Mixflo™ system. Based on cost and air emissions, the Mixflo™ system was selected, and a field-scale system was designed for the French Ltd. Site. This system is currently operating.