The packing materials investigated were 1-inch Pall rings, Number 1 Jaeger Tri-Packs, 1-inch Flexi-saddles, and Flexipak Type II structured packing. Analysis of the groundwater in the fuel storage area by the headspace technique using gas chromatography/mass spectroscopy (GC/MS) identified 16 volatile organics. The six major VOC contaminants identified were: n-pentane, cyclohexane, trichloroethylene, benzene, ethylbenzene, and xylene. Field trials in a pilot-scale air stripper (1.5 feet diameter by 10 feet, with an 8-foot packed section) yielded removal efficiencies above 90 percent for all VOCs except isobutane, under a water loading rate of 2.13 cu. ft./min.sq.ft. (0.649 cu. f./min./sq. m.), and a volumetric air-to-water ratio (G/L) of approximately 65). Based on measured overall mass transfer coefficients (KLa), a packed-tower height of 25 to 30 feet should be effective in achieving a 95 percent removal efficiency. Of the four packing materials tested, the 1-inch Pall rings consistently exhibited the highest mass transfer coefficients for all the VOCs over the broadest range of air- and water-loading conditions. In some cases, the other packings had mass transfer coefficients comparable to the Pall rings for some but not all the VOCs or only for a more narrow range of tower operation conditions. However, since the Pall rings had the highest operating pressure drop, economic trade-off analyses of system capital and operating costs should be performed in making a packing selection for a full-scale treatment system.