Despite a dramatic uptick in auto traffic since the 2002 Winter Games, Park City and the Snyderville Basin have remarkably clean air in terms of particulate-matter pollution. Summit County officials measured PM 2.5 pollutants between Dec. 18 and March 26. They found that even on the worst days air quality was good, according to Steve Jenkins, director of the county's health department.

This is the first year Summit County has tested air quality, Jenkins said. The county hopes to continue gathering data during the next two years to establish a record that would serve as a base line for future studies. Mary Jacquin, of Park City's Utah Moms for Clean Air, applauded the testing. She hopes the county and state also will test for ozone and other air pollutants.

Clean air is important, said Summit County Commissioner Sally Elliot. For health reasons, of course, but also because Park City's and west Summit County's economies depend on tourism. - Christopher Smart