The York Area MPO (encompassing York County) must make separate conformity determinations for the two criteria pollutants for which it is in maintenance and nonattainment, ozone and PM2.5.
Clean Air Act
Since vehicular emissions contribute to ozone and PM2.5 violations, the Clean Air Act requires transportation planners in nonattainment and maintenance areas to consider the air quality impacts of their proposed plans, programs, and projects. These activities, if subject to federal involvement, must be shown to conform based on the requirements for each pollutant. This document and supporting analysis demonstrates that the YAMPO Transportation Improvement Program (TIP) and Long Range Transportation Plan (LRTP) for the years stated conform to the 1997 8-hour ozone and the 1997 annual and 2006 daily (24-hour) fine particulate (PM2.5) National Ambient Air Quality Standards (NAAQS) and ensures that the findings meet all current ozone and PM2.5 criteria established by the U.S. Environmental Protection Agency (EPA).