Health and Safety Research Division, sponsored by EPA, conducted a study to quantify emission factors from stacks, spills, fugitives, storage, and treatment for a typical hazardous waste incinerator facility. Engineering participated in preparing flowsheets and providing calculations for fugitive emissions. Typical block-flow diagrams were developed two types of hazardous waste incinerators (rotary kiln and liquid-injector) and for three capacities (small: 1 MM Btu/hr, median: 10 MM Btu/hr, and large: 150 MM Btu/hr). Storage reqirements and support services were determined in more detail. Using the properties of a typical waste, fugitive emissions were determined, including emissions from pump leaks, valve leaks, flange leaks, and tank vents. An atmospheric dispersion model was then employed to calculate atmospheric concentration and population exposure estimates. With these estimates, an assessment was performed to determine the percentage of concentrations and exposure associated with selected emissions from each source at the incineration facility. Results indicated the relative importance of each source at the incineration facility. Results indicated the relative importance of each source both in terms of public health and pollution control requirements.