1. CARBON FRACTIONS & Southern Nevada Air Quality Study (SNAQS) Judith Chow Desert Research Institute, Reno, NV February 5, 2002

2. Southern Nevada Air Quality Study (SNAQS) Desert Research Institute Federal Transit Administration Clark County Health Department Clark County Department of Comprehensive Planning Nevada Department of Motor Vehicles

3. SNAQS Objectives  On-road particle emissions sensor (FTA)  Accurate transportation emissions model (FTA)  Frequencies and magnitudes of PM 2.5 and O 3 transported from distant sources (FTA)  Quantify dust and exhaust emissions from on- road and off-road emitters for different seasons (FTA, CCDCP, DMV)  Quantify PM 2.5 composition, source contributions, and effects of visibility (CCDCP, EPA)

4. Expected SNAQS Products Technical basis for Las Vegas conformity and implementation plans Enhancement of on-road emissions sensing technology Planning tools and procedures that can be applied in other urban areas Increased understanding of pollutant trade-offs for transportation emissions Effects of regional pollution on local NAAQS attainment in desert southwest

5. On-Road Sensing Develop and test LIDAR system for exhaust and road dust particles Combine with existing on-road technology for CO, NO x, NMHC, and CO 2 Apply to different roadway conditions (congestion, construction, grades), operating conditions (cold starts, power enrichment), and vehicle types (gasoline, diesel, CNG, smokers)

6. The LORAX System

7. Off-Road Emitters Apply remote sensing at roadway and other construction sites (exhaust plumes and dust clouds) Measure PM emissions potential of trackout onto paved roadways Add roadway and other construction activities to emissions model

8. Regional/Local Contributions Measure surface and upper air winds Evaluate changes in vertical mixing with season Apply methylchloroform as indicator of S. California contributions Apply advanced air quality and meteorological models to collected data

9. Upper Air Winds by SODAR

10. PM 2.5 Source Contributions Apply receptor source apportionment models to PM 2.5 concentrations and chemical composition Integrate transportation emissions with other emissions in gridded emissions inventory Apply advanced air quality and meteorological models to revised emissions Reconcile source and receptor models Apply model to emissions reduction scenarios

11. Schedule April, 2000 through March, 2001: Ambient monitoring and modeling year of record August, 1999: Upper air met monitoring at Jean and Palo Verde. Methylchloroform measurements at Jean December, 1999: Upper air met monitoring at LV wash February, 2000: On-road vehicle pilot tests. Subsequent tests in summer and winter 2000/2001 August, 2000: Select and set up air quality modeling system

12. Schedule December, 2000: Emissions inventory revisions June, 2001: Complete data base for year of record December, 2001: Complete modeling, analysis, and reports