Task 91, FY 1997, "Transportation Implications of Proposed Changes to National Ambient Air Quality Standards", (Gary Hawthorn Associates, Ltd., Gary Hawthorn). The research for this project was intended to help state agencies assess air-quality issues and the EPA's new air quality standards. It will address anticipated effectiveness of regional control strategies versus local control programs, impacts of the new standards on transportation planning, current conformity requirements in light of the new standards, and the effect of the new standards on linkages between the CAAA and the ISTEA. The contractor monitored regulatory progress for the new National Ambient Air Quality Standards for ozone and particulate matter. The final report has been prepared and submitted to AASHTO for distribution. (NCHRP Staff: R.D. McCready)