Secondary treated municipal wastewater from the City of Phoenix was applied to three laboratory-scale soil columns at various infiltration rates typical of high-rate land application systems, and a fourth column was inundated with tapwater to serve as a control. Samples of the column influent and effluent streams, collected with continuous flow-through systems to prevent organic volatilization losses, were analyzed for organic compounds using gas chromatography/mass spectrometry. The secondary wastewater contained chloroform, 1,1,1-trichloroethane, and tetrachloroethylene in the range of 1–10 μg l −1. These compounds also were present in the soil column effluents apparently with complete breakthrough of chloroform. Also present in the column influents and effluents were up to 1 μg l −1 of hydrocarbons, alcohols, ketones, chlorinated and unchlorinated aromatics, phthalates, chlorinated anisoles, a few pesticides, and several unknown compounds. Several compounds present in the secondary wastewater were not found in the column effluents. Conversely, a few compounds found in the column effluents were not detected in the wastewater. For many compounds, column effluent concentrations were lower than column influent values. Infiltration rate over the range studied did not influence the degree of organic removals observed. The tapwater column effluent contained the same compounds and concentrations as the other columns, which suggests prior storage and leaching of the organic compounds from the soil. This study was performed to give a general indication of the behavior of trace organics in soil column systems with an attempt to indicate the presence of various removal processes. Evidence is given for biodegradation, sorption, and volatilization.