Air Quality

Air pollution comes from many different sources, including industry, transportation and agriculture. It affects both human health and the environment, including plants, animals, and visibility, as well as the built environment. Airborne pollutants interplay in complex ways; this chapter considers air quality in terms of a number of pollutants, including particulate matter, carbon monoxide, ozone, toxics and greenhouse gases.

This section evaluates impacts to air quality from each of the four alternatives, drawing on air quality modeling and other relevant information obtained from the Puget Sound Regional Council, the Puget Sound Clean Air Agency (PSCAA), the United States Environmental Protection Agency (EPA), the Washington State Departments of Ecology (Ecology) and Transportation (WSDOT), and King, Kitsap, Snohomish, and Pierce Counties.