The paper discusses an EPA study of the generation and control of air pollutants from the combustion of Orimulsion, a high-sulfur liquid petroleum fuel composed of approximately 70% Venezuelan bitumen, 30% water, and trace amounts of surfactant. (NOTE: It is being used as the primary fuel in several utility generating stations around the world, and has been proposed, although not currently being used, as a utility fuel in the U.S.). The study included a review of previous studies of air pollution emissions from Orimulsion combustion and a series of tests that measured pollutants generated by Orimulsion in EPA's pilot-scale combustion research facilities in Research Triangle Park, N.C. Data on emissions of carbon monoxide, nitrogen oxides (NO-x), particulate matter, sulfur dioxide, and sulfur trioxide showed substantial similarity to emissions reported from high-sulfur heavy fuel oil. Control technologies were evaluated to determine their effectiveness in reducing emissions from boilers burning Orimulsion. Data from the studies indicate that properly designed, commercially available technologies can be effective in reducing pollutant emissions from Orimulsion-burning facilities. EPA's pilot-scale tests compared the generation of air pollutants from Orimulsion 100 (the now-discontinued original formulation of the fuel), Orimulsion 400, and a high-sulfur No. 6 fuel oil.