Presentation to the Air Quality Forum – August 9, 2005 Clark County PM 10 Saturation Study Robert A. Baxter, CCM T & B Systems, Inc.

Background  Clark County is in non-attainment for the 24- hour PM 10 NAAQS  2001 SIP made a commitment to conduct a PM 10 saturation study  Study to begin in 2004 and be completed in 2006

Study Goals and Objectives  Determine neighborhood impacts of major sources  Determine PM concentrations in locations that may not be covered by the current monitoring network  Determine inter-basin and intra-basin transport during high wind events

Study Design  Evaluate existing data sets for apparent trends  Design the monitoring network  Sampler evaluation (fall 2004)  Acquire appropriate saturation sites  Saturation study (April 15 – June 30)  Evaluate the collected data

PM 10 Data Evaluation Years 2000 – 2003

DAQEM PM 10 Site Locations

PM 10 Site Locations

DAQEM PM 10 Site Locations

PM 10 Site Locations

PM 10 Instrument Evaluation  Two evaluation sites –Crustal PM 10 –Combustion emissions related PM 10  Evaluation Criteria –Continuous Method –Acceptable performance –No environmental controls –Solar power –Inconspicuous –Cost-effective –Reliable

PM 10 Instrument Evaluation October/November 2004

Selected Instrumentation  TSI DustTrak  External data logging  Extended sample inlet  Solar/available power

Instrument Siting

Saturation Sampling Schedule  Study Period = April 15 – June 30  Continuous sampling for study duration  QA program for network assessment and performance  Weekly data downloads and QC checks

What Have We Seen?  Fall and winter rainy periods  Late spring/early summer high wind events  Wind events produced short lived PM 10 “episodes”  No PM 10 exceedances in the Las Vegas Valley network  Desert environment is rough on instrumentation

Questions? Please contact: Department of Air Quality and Environmental Management (DAQEM) (702)