The fate of both dispersed oil and whole oil was studied in a near-shore mesocosm environment. The 10-day experiment simulated an oil spill and was conducted at a wave tank facility (Coastal OilSpill Simulation System) in Corpus Christi, TX. In the oiled treatment, oil was stranded on sediments, tank walls, and other surfaces in the tank. Floating oil was also observed for several days. In the chemically-dispersed oil (CDO) treatment, little oil sorption was evident, and there was little or no floating oil. When oil concentrations were converted to oil mass values for each compartment, the oiled treatment had consistently larger masses of oil associated with sediments as compared to the CDO treatment. Less oil was moved out of the tanks in the oiled tanks in comparison to the CDO tanks. Larger amounts of oil were attributed to-free-phase oil (either sorbed or floating) for the oiled treatment, as compared to the CDO treatment. Approximately 50% of the applied oil for the oiled treatment remained in the tanks sorbed to sediments and other surfaces. The remainder of the oil was removed via the effluent. In the chemically-dispersed oil treatment, virtually all of the applied oil was flushed from the tanks. The chemical dispersant was effective in reducing petroleum contamination in the near-shore environment. This is an abstract of a paper presented at the 22nd Arctic and Marine Oil Spill Program, AMOP Technical Seminar (Calgary, Alberta, Canada 6/2-4/99).