This paper presents the field demonstration results of the ultraviolet radiation (UV)/oxidation technology developed by Ultrox International, Santa Ana, California. The technology was demonstrated at the Lorentz Barrel and Drum (LB&D) site in San Jose, California, under the United States Environmental Protection Agency's Superfund Innovative Technology Evaluation program. The UV/oxidation technology uses UV radiation, ozone, and hydrogen peroxide to oxidize organic contaminants present in water. At the LB&D site, this technology was evaluated in treating groundwater contaminated with volatile organic compounds (VOCs). The Ultrox system achieved VOC removals greater than 90 percent. The majority of VOCs were removed through chemical oxidation. However, for a few VOCs, such as 1,1,1-trichloroethane (1,1,1-TCA) and 1,1-dichloroethane (1,1-DCA) stripping also contributed toward removal. The treated groundwater met the applicable discharge standards for disposal into a local waterway at 95 percent confidence level. There were no harmful air emissions from the Ultrox system into the atmosphere.