Fugitive Dust Research at DRI

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Fugitive Dust Research at DRI

• Portable Wind Tunnel
• Unpaved Road Dust Emission Factors
• TRAKER measurements at Lake Tahoe
• Near Field Deposition
• Research by
• Hampden Kuhns
• Vicken Etyemezian
• Jack Gillies
• Alan Gertler
• Djordje Nikolic
• Sean Ahonen
• Cliff Denney
• John Skotnik
• Nicholas Nussbaum
• Dave Dubois
• Jin Xu

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1. Portable Wind Tunnel
USDA-ARS Wind Erosion Research Unit
http//www.weru.ksu.edu/vids
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LWT at Ft. Bliss, TX

• J. Gillies and B. Nickling testing emission flux
  potential
• LWT is closest measurement to a standard
• SWT - e.g. D. James (UNLV), D. Gillette (NOAA)
• Concerns with boundary layer development, maximum
  wind speeds, and accounting for saltation

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PI-SWIRL Schematic
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PI-SWIRL v.2
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The PI-SWIRL-ogram
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PI-SWIRL Status

• Version 3 is currently being tested
• Lower weight and smaller size
• Faster measurement
• Low cost custom circuitry
• Patent application filed
• PI-SWIRL has been collocated with LWT to draw
  empirical relationship
• Data still being analyzed
• Contact Vic Etyemezian (vic_at_dri.edu) for more
  information

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2. Unpaved Road Dust Emission Factors
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Emission factor calculated as horizontal flux of
PM10 passing instrumented towers
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Unpaved Emissions Measured on Flux Towers in Ft.
Bliss TX (April 2002)
Vehicle Weight (kg) Wheels
Dodge Neon 1,176 4
Ford Taurus 1,516 4
Dodge Caravan 1,759 4
HUMVEE 2,445 4
TRAKER (Chevy Van) 3,100 4
26 UHAUL Truck 5,227 6
LMTV 8,060 4
Freightliner (Tractor) 8,982 22
HEMMET 17,727 8
5-ton Truck 14,318 6
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EFPM10 b W S
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Unpaved Road Dust Emission Factor Status

• Emission factors are dependent on vehicle speed
  and weight
• Emission potentials of unpaved road soils were
  relatively constant in Ft. Bliss TX based on
  TRAKER.
• Need to determine how emission potential varies
  in other regions.
• Time since last rainfall is correlated with
  unpaved road emission factors
• John A. GILLIES, Vicken ETYEMEZIAN, Hampden
  KUHNS, Djordge NIKOLIC Dale A. Gillette (2004)
  Effect of Vehicle Characteristics on Unpaved Road
  Dust Emissions. Accepted in Atmospheric
  Environment
• Kuhns H., V. Etyemezian, J. Gillies, S. Ahonen,
  C. Durham, D. Nikolic (2003) Spatial Variability
  of Unpaved Road Dust Emissions Factors near El
  Paso, Texas. Accepted in J. Air Waste Manage.
  Assoc.
• Kuhns H., V. Etyemezian, M. Green, Karin
  Hendrickson, Michael McGown, Kevin Barton, Marc
  Pitchford (2004) Vehicle-based road dust
  emissions mesasurement (II) Effect of
  precipitation, winter time road sanding, and
  street sweepers on PM10 fugitive dust emissions
  from paved and unpaved roads. Atmospheric
  Environment.

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3. Testing Re-entrained Aerosol Kinetic
Emissions from Roads (TRAKER) Measurements in
Lake Tahoe
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• Particle Sensors
• TSI DustTrak 5830
• Grimm Particle Size Analyzer 1.108
• GPS
• Ashtech/Magellan Promark X

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Data Acquisition and Processing

• Lab View program displays and logs data from
• 6 DustTraks
• 3 Grimms
• 1 GPS
• Uniform time stamp applied to all data for
  synchronization
• Data tables are loaded into MS Access for
  processing and analysis

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TRAKER Signal vs Vehicle Speed

• T Ctire Cbkgrnd
• T a S3
• On the same paved road the TRAKER signal
  increases with the speed cubed
• Factoring out speed leaves a signal proportional
  to the emission potential of the road.

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Flux Ladder in Lake Tahoe
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Roadside PM Flux MeasurementsPM concentration
profile drops off with heightReal time
instruments help when wind doesnt cooperate
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TRAKER vs Horizontal PM Flux
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Comparison of EFs with Snow Precip
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Spatial/Temporal Variability of Road Dust
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Tahoe TRAKER Status

• Road Dust EFs drop by 70-80 from Spring to
  Summer
• Previous TRAKER Calibration based on unpaved
  roads was way off
• Maybe due to whole fleet vs just TRAKER?
• Cities roads are dirtier than high speed rural
  highways
• Something is different b/w CA and NV roads that
  create less dust
• Draft report completed for CARB in June. Final
  expected by Sept.

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Transportable Fraction of Dust

• Basic Problem Statement Inventory of dust
  sources appears to be too high compared with what
  we find in the air
• Possible Causes
• Our inventory as measured at the source is
  inaccurate
• We are not accounting for removal of dust near
  the source

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Evolution of Plume Downwind
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Approaches

• Modeling
• Advantages Inexpensive, easy to simulate
  countless environments
• Disadvantages Who knows if its right!
• Measurement
• Disadvantage Expensive and labor intensive (e.g.
  Gillies SERDP), unclear if possible to measure
• Advantage Results based on a Real data

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Measurements of TFgt95 at 100 m at Ft. Bliss
(Etyemezian et al., 2004)lt20 at 100 m at
Dugway Proving Grounds Mock Urban Environment
(Veranth et al., 2004)USDA Proposal Submitted
to measure TF in cornfield over growing season
(Gillies et al., 2004)
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Change in Integrated Horizontal Flux at Ft. Bliss
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Comparison of Model and Measurements
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Change is Particle Size Distibution Downwind
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Transportable Fraction Research Status

• Initial attempt completed (WESTAR report)
• Next round of research should target
• Additional field studies
• Model improvement
• Consideration of vegetation, landscape

Etyemezian V., J. Gillies, H. Kuhns, D.
Gillette, S. Ahonen, D. Nikolic, and J. Veranth
(2004) Deposition and removal of fugitive dust in
the arid southwest United States Measurements
and model results. Acceptd in J. Air Waste
Manage. Assoc.