An experiment was conducted at a wetland research facility, investigating the behavior of chemically dispersed oil (CDO) using an oil spill dispersant. The research site is located on the San Jacinto River near Houston, Texas. The experimental treatments included oiled control, “high-dose” CDO (1:10 dispersant-to-oil ratio, DOR), “low-dose” CDO (1:20 DOR), as well as an unoiled control. Fourteen 5 m x 5 m plots were used for the experiment, four plots for each oiled treatment and two plots for the unoiled control. The treatments were assigned to plots using a randomized complete-block design. Twenty-one liters of Arabian medium crude oil was applied systematically to each plot. For the CDO treatments, the premixed dispersant-plus-oil solution was first added to containers of river water (either 1:10:200 or 0.5:10:200 dispersant-oil-water ratios), and the resulting solution was applied systematically to the respective plots. This method of CDO application was designed to simulate the movement of a dispersed-oil plume into a wetland environment. Sediment samples were taken over a 99-day period, using a 5-cm diameter-coring device. The GC-MS results for both target saturate and target aromatic hydrocarbons were normalized to 17?, 21?-(H)hopane to separate biotic and abiotic removal mechanisms and to minimize spatial heterogeneity. Target compound analyses indicated no significant differences in the biodegradation rates for the three oil treatments. There were, however, significant differences in the amount of oil initially flushed (physical removal) from the plots of both CDO treatments as compared to the oiled-control treatment.