Prescribed Burning (PB) Impacts on Air Quality in the South-Eastern U.S.

1
Prescribed Burning (PB) Impacts on Air Quality
in the South-Eastern U.S.

• Sponsors
• DoD/EPA/State P2 Partnership,
• USAIC, IMA-SERO

• Karsten Baumann, Rick Saylor, Ben Hartsell, Eric
  Edgerton
• Atmospheric Research Analysis, Inc.
• Contributors
• M. Clements, P. Gustafson, J. Greenlee, A.
  Braswell, D. Chan, K. Redmond,
• J.B. Flanagan, S. Lee, M.E. Chang, A.G. Russell,
• J.J. Schauer, L.P. Naeher, D.D. Blake

2
PB Benefits and Objectives

• Reducing wildfire risk
• Preparing sites for tree regeneration
• Controlling disease and tree competition
• Disposing of logging debris
• Improving wildlife habitat
• Improving understory forage for grazing
• Enhancing aesthetics
• Perpetuating fire-dependent species
• Managing endangered species

3
BUT PB is 3rd largest anthropogenic source of
primary PM2.5
with gt 8 million acres burned in SE-US mostly
Jan-Jun.
EPA (2004), Air Quality Criteria for
Particulate Matter, Fourth External Review Draft
Report, EPA-600/P-99-002, aD, bD, Office of
Research and Development, Research Triangle Park,
NC, with data from http//www.epa.gov/ttn/chief/tr
ends/. Wade D.D., B.L. Brock, P.H. Brose. J.B.
Grace, G.A. Hoch, W.A. Patterson III, Chapter
453-96. In Brown J.K., Smith J.K. (Eds.)
Wildland Fire in Ecosystems Effects of Fire on
Flora, Gen. Tech. Rep. RMRS-GTR-42-2 Ogden, UT.
USDA-FS, Rocky Mountain Research Station, 2000.
4
Conflict Intensely Managed Areas Neighboring MSAs
Military Installations in SE-US are required to
maintain ecosystem by prescribed burning, risking
violations of the NAAQS.
Most Army installations reside next to cities
subject to regulatory monitoring (MSA). Reduction
of daily PM2.5 NAAQS from 65 to 35 mg m-3 will
challenge most counties to stay in compliance.
Endangered Species Act
Clean Air Act
    Managed Nearest Popul.
Fort Area City 2000
    (acr)   Census
Benning GA 96,000 Columbus 186,000
Gordon GA 56,000 Augusta 195,000
Stewart GA 270,000 Savannah 132,000
Bragg NC 162,000 Fayetteville 121,000
Campbell TN 140,000 Clarksville 104,000
Jackson SC 52,000 Columbia 116,000
Rucker AL 63,000 Dothan/E.prise 70,000
5
PB across South-Eastern U.S. in March 2002
Wang (GIT), Barnard (Mactec), et al., VISTAS Data
Analysis, personal communication, 2006.
6
Prescribed Burning (PB) in Georgia gt 1,000,000
acres annually, majority in winter half
7
PM2.5 Wind Roses Seasonal Differences Across
GAIndications for Regional and Local Transport
Fall line Air Quality Study (FAQS), Final Report
available via http//cure.eas.gatech.edu/faqs/inde
x.html
8
April 2004 Prescribed Burning Source - Receptor
Field Studyto demonstrate procedures that
directly link PB emissions with source impact
areas.
9
Emission Profiles and Factors

• Organic carbon (OC) is a dominant species of
  particulate emission, followed by EC and K.
• Enhanced emissions (2-3 orders gt background) of
  Aromatics (benzene, toluene, xylenes), NH3 and
  Biogenics (isoprene, a-/b-pinene), important
  precursors for formation of secondary PM.
• Emission Factors (EF) higher at smoldering than
  flaming even more as C content increases.

Lee et al., Environ. Sci. Technol. 39, 9049-9056,
2005
10
Comparisons With Other Emission Studies

• Different identified organic mass concentrations
  and fractions
• Different profile (different fuels, different
  combustion conditions)
• Significant level of cholesterol seen only in
  real world emissions!

Fireplace
Lee et al., Environ. Sci. Technol. 39, 9049-9056,
2005
11
Fine PM Mass and Composition at Receptor Sites

• Organic mass (OM 1.6OC) and sulfate are the
  major species of the measured ambient PM2.5
  comprising more than 65 of its mass.

Lee et al., Environ. Sci. Technol. 39, 9049-9056,
2005
12
CMB Receptor ModelingOrganic Carbon (OC) Source
Apportionment at Receptors
rain

• Motor vehicles and PB are major contributors to
  ambient OC.
• PB emissions contribute esp. during and
  immediately after the burns.
• Large unexplained fraction during (after)
  regional rain events, possibly due to SOA? Needs
  further investigation!

Lee et al., Environ. Sci. Technol. 39, 9049-9056,
2005
13
Importance of direct (primary) and indirect
(secondary) emissions How fast are they formed?
O3 SOA Others
CO CO2
VOCs
NOx
PM
Toxics
14
Fort Benning 400 acr PB from ca. 4 miles away
15
PMF Receptor Modeling in Urban SE-US Using
STNPM2.5 Factor Contributions at Birmingham, AL
Similarities between Biomass Burning and SOC
contributions
Baumann et al., JAWMA 58, 27-44, 2008
16
PMF Receptor Modeling in Rural SE-US Using
SEARCHPM2.5 Factor Contributions in Q1 vs.
Q3

• Secondary sulfate factor has more regional
  character with higher FCE in Q3.
• Prescribed burning factor has more local features
  with higher FCE in Q1.
• YRK least rural and influenced by ATL air shed.

Baumann et al., JAWMA submitted, 2008
17
PMF Receptor Modeling in Rural SE-US Using
SEARCHDistribution of Major Precursor Sources
SO2 and OVOC
EPA, Technology Transfer Network, Clearinghouse
for Inventories Emissions Factors, 2002
National Emissions Inventory Data
Documentation, accessible via http//www.epa.gov/t
tn/chief/net/2002inventory.htmlinventorydata.
NOAA National Environmental Satellite, Data, and
Information Service (NESDIS) with 2005 data
extracted from the National Geophysical Data
Center (NGDC) via http//map.ngdc.noaa.gov/website
/firedetects/viewer.htm.
18
PMF Receptor Modeling in Rural SE-US Using
SEARCHPM2.5 Daily Source Contributions in
Jan-Feb 2005 at OAK

• 1/25 and 2/6 2005 saw highest and second highest
  PM2.5 and OC concentrations at OAK.
• In both events PB contributions dominate both
  PM2.5 and OC concentrations.
• Sulfate and sSO4 contributions are low during 1st
  and high during 2nd event.
• Fraction of sulfate neutralized in NH4-NO3-
  milieu is 78 and 87 during 1st and 2nd event,
  respectively.
• OM/OC ratio is 1.4 during 1st and 1.8 during
  2nd event.
• Arrival of mostly rural air mass from W on 1/25
  vs. urban/SO2 influenced air mass from E on 2/6.
• ? Do OOE on 2/6 contain S (e.g. in form of
  organosulfates per Surratt et al., 2008)?
• SOA formation indicated by un-apportioned OC,
  OC/EC and SOC/OC, peaks during both events.
• ? Back-trajectories and on-site observations
  suggest fast (few h) SOA formation in PB plumes.

Baumann et al., JAWMA submitted, 2008
19
Main Conclusions

• PB is a regional source with local impacts on
  rural receptors.
• DoD is most sensitive to PB application due to
  civilian encroachment (opportunity to test
  alternative land management practices?).
• Both CMB and PMF yield significant contributions
  from a source/factor resembling PB to receptor
  PM2.5 and OC.
• PMF plausibly reflects lower BB-FCE in urban
  environs (BHM), while higher BB-FCE are obtained
  in rural environs (CTR, OAK).
• Rural receptors see highest BB-FCE during highest
  PB activity (Q1).
• Reactive PB emissions suggest rapid SOA formation
  as indicated by OAK case study (being further
  investigated).