Apportionment of ambient primary and secondary PM_2.5 during a 2001 summer intensive study at the CMU supersite and NETL Pittsburgh site using PMF2

Apportionment of primary and secondary pollutants during a July 2001 summer intensive study at the Carnegie Mellon University Supersite (CMU) about 5 km east of downtown Pittsburgh and at the National Energy Technology Laboratory (NETL) PM characterization site is presented. Data were available for five samples collected each day at the Supersite and four samples collected each day at NETL during the summer intensive, three samples during the day and either two or one, respectively at night. Input to the PMF2 analysis included the concentrations of PM_2.5, measured both with a PC-BOSS and a TEOM monitor, the nonvolatile and semi-volatile organic material, elemental carbon and PIXE determined trace metal components of the PM_2.5, and volatile gas phase organic material, NO_x, NO₂, and O₃ concentrations for the various samples. A total of nine sources at NETL and 10 sources at CMU were identified in the PMF analysis. These included primary emissions from crustal material, mobile emissions (both gasoline spark source and diesel), and three near-by sources high in trace metals. Source nine at NETL and 10 at CMU were due to primary mobile gasoline (spark source) emissions. The highest concentrations of this source were routinely seen in the early morning samples, consistent with the expected contribution of the morning rush hour traffic, coupled with a lower mixing height in the morning. This is an abstract of a paper presented at the 98th AWMA Annual Conference and Exhibition (Minneapolis, MN 6/21-24/2005).