Aeration has recently been employed as a method for removing trace organic contaminants, such as trichloroethylene, from drinking water supplies. Preliminary applications of the air stripping process suggest that it may be a more economical method than removal via granular activated carbon or adsorbent resins. A procedure has been developed for the process design of air stripping in packed towers, which follows Henry´s law at low concentrations. The design methodology provides an analytical method for estimating the relative cost of air stripping for the removal of volatile organic compounds as well as a quantitative framework for design and evaluation of pilot plant studies. Various aeration methods are diffused aeration, coke tray aerator, countercurrent packed towers, and cross-flow towers. Also covered are liquid versus gas-controlled mass transfer, development of removal efficiency equation, height of transfer unit, air-to-water ratio, and pressure drop.