Air quality impact evaluation of a hypothetical fire-fighter training facility

Human Health Risk Assessments (HHRAs) have become a required component in the permitting process for hazardous waste incinerators and boilers and for closure or evaluation of chemical and petroleum facilities. However, although not currently required, these evaluations are also essential for additional daily processes having the potential to adversely impact the environment. One such process includes emissions produced from a firefighter training facility. Firefighter training facilities perform scenarios to enhance the firefighting ability of the trainees. Three typical scenarios conducted at such a facility include air rescue and firefighting, building fire simulation, and propane system fires. During the course of these scenarios, various fuels (e.g., gas, diesel, wood, hay, and propane) are burned, resulting in the release of both uncombusted fuel constituents and other constituents formed during the combustion process (e.g., carbon monoxide and volatile organics). These constituents are potentially transported by air to the surrounding communities where people may come in contact with the constituents. To evaluate the potential health effects of these releases, a multimedia, multipathway HHRA was conducted using the USEPA guidance document, Human Health Risk Assessment Protocol for Hazardous Waste Combustion Facilities (USEPA 1998). This assessment included both direct (inhalation) and indirect pathways of exposure to constituents potentially emitted during the training scenarios. Priority pollutants (i.e., particulate matter, sulfur oxides, nitrogen oxides, and carbon monoxide) were evaluated in this assessment. Estimated emission rates for the priority pollutants were used to estimate air concentrations that were then compared with their respective National Ambient Air Quality Standard. The results of the HHRA indicated a low potential of increased risk to the surrounding population from the combustion of materials used in the firefighter training scenarios. The highest estimated total excess lifetime cancer risks were 2 in 100 million and 4 in 10 million for the direct and indirect pathways, respectively. These values were substantially less than the USEPA\u27s (USEPA 1998) benchmark of 1 in 100,000 for cancer risks and 0.25 for noncarcinogenic hazards, even when summed over all constituents and scenarios