This 68-page PDF reports on the relative impacts of the proposed winter use alternatives on ambient air quality in the Greater Yellowstone Area. Short-term air quality analyses were performed by means of atmospheric dispersion modeling for carbon monoxide (CO) and particulate matter. A screening level particulate matter (PM10) increment analysis and visibility modeling also were performed for the full year of each scenario. In addition, the total winter-season mobile emissions of CO, PM10, nitrogen oxides (NOX), hydrocarbons (HC), and selected toxic air pollutants inside the park units were calculated for the full year of each scenario.
