Transcript National Ambient Air and Emissions Monitoring Strategy

PM10-2.5 Methods Update
and Network Design
Presentation for WESTAR
San Diego, CA
September 2005
Peter Tsirigotis
Director
Emissions, Monitoring, and Analysis
Division;
U.S. EPA Office of Air Quality, Planning
and Standards
PM10-2.5 Methods Update
• Multi-city field study of commercially available PM10-2.5
technologies completed and reviewed by CASAC
Technical Subcommittee in 2004
– Included continuous methods for hourly data and filter-based
methods to obtain integrated daily samples
• Additional field study in Phoenix completed spring 2005
– Several technologies modified to improve performance prior to
this study
• New field study being deployed in Birmingham, AL
• Upcoming meeting of the CASAC scheduled for
September 21-22, 2005 to provide:
– Peer review on a PM10-2.5 Federal Reference Method (FRM)
– Consultations on the evaluation of PM10-2.5 field studies,
optimization of the PM2.5 FRM, equivalency criteria for PM2.5 and
PM10-2.5, and data quality objectives for PM10-2.5.
– Materials available at:
http://www.epa.gov/ttn/amtic/files/ambient/pm25/casac/casacmemo.pdf
PM10-2.5 Methods Update
Take Home Messages:
• Filter-based difference method (separate low-volume FRMs for PM10
and PM2.5) has better data quality compared to other commercially
available methods
– Not expected to be widely deployed, but will serve as basis of comparison
for approving continuous methods
• Continuous method evaluations have demonstrated high sample
completeness, and good precision and correlation between methods
– Biases do exist between methods; however, new studies may address this
• Samplers potentially usable for speciation
– Coarse channel of filter-based dichotomous sampler
– Analysis of PM10 filter and subtraction of Speciation Trends Network PM2.5
data
– Customized samplers specially designed for this purpose
• Data Quality Objectives demonstrate the value of continuous methods
to reduce uncertainty in support of a potential daily PM10-2.5 standard
PM10-2.5 Network Design
• Available epidemiological evidence is being considered
in designing the coarse particle monitoring network.
– Greatest health concern in urban areas where particles become
enriched with contaminants from road dust and industrial
sources
– Less concern for exposure to natural materials of geologic origin
– Lack of evidence limits conclusions on toxicity of agricultural and
mining sources
• CASAC concluded that available evidence from health
studies suggests focus on urban, not rural coarse
particles.
• More narrowly defined indicator (UPM10-2.5) proposed to
characterize risk from urban sources such as resuspended road dust typical of high traffic-density areas
and emissions from industrial sources
PM10-2.5 Network Design
• Proposed design similar in concept to PM2.5
monitoring for the daily standard
– Focus on areas of high population density and
proximity to primary industrial sources of urban
particles
– Rural monitoring as part of NCore Level 2 multipollutant sites
– Speciation requirements under consideration
• Minimum EPA monitoring requirements based
on criteria including population size and
estimated UPM10-2.5 concentrations
• Draft changes to 40 CFR 58, Appendix D and E
must be signed for NPRM by December 20,
2005