Most people think of Alaska as a cold but pristine wilderness, occasionally interrupted by human settlements.  In fact, Fairbanks (population 35,000) has one of the more intractable PM2.5 problems of any "metropolitan" area in the United States, with 25-30 exceedances per year and a maximum daily average concentration in 2008 of 120 ug/m3.  Frank Di Genova of Sierra Research will talk about his work in attempting to unravel the causes of high PM2.5 concentrations in that community.  The presentation will describe the methodology and preliminary results from operating a mobile measuring platform in Fairbanks to identify the contributions of potential source contributors such as wood burning, space heating, mobile sources, waste oil burning, and coal burning.