Composition, Sources, and Emissions PM2.5

Washington DC-MD-VA NAA

Sunil KumarTAC, COG

June 8, 2007

Washington DC-MD-VA PM2.5 NAA

PM2.5 Composition High Level DaysMcMillian (Washington, DC) - 2001-2003

Organics (k=2.4)50%

Geological2%

Soot4% Nitrate

19%

Sulfate13%

Ammonium10%

Trace Elements1%

Salt1%

Average 24-Hour PM2.5 Concentration = 38ug/m3Number of Days > 35ug/m3 = 4

Salt1%

Trace Elements1%

Ammonium12%

Sulfate20%

Nitrate20%

Soot4%

Geological2%

Organics (k=2.4)40%

Average 24-Hour PM2.5 Concentration = 39ug/m3Number of Days > 35ug/m3 = 1

Winter Spring

Salt0%

Trace Elements1%

Ammonium12%

Sulfate40%

Nitrate2%

Soot1%

Geological2%

Organics (k=2.4)42%

Average 24-Hour PM2.5 Concentration = 43ug/m3Number of Days > 35ug/m3 = 12

Organics (k=2.4)52%

Geological2% Soot

5%Nitrate

6%

Sulfate25%

Ammonium9%

Trace Elements1%

Salt0%

Average 24-Hour PM2.5 Concentration = 38ug/m3Number of Days > 35ug/m3 = 2

FallSummer

PM2.5 Composition STN DataMcMillian (Washington, DC) - 2004

Winter Summer

PM2.5 Composition STN DataMcMillian (Washington, DC) - 2004

Major species, McMilan Reservior, DC, in 2003

0

10

20

30

40

50

60

70

2003

0103

2003

0115

2003

0130

2003

0211

2003

0223

2003

0310

2003

0319

2003

0328

2003

0409

2003

0506

2003

0518

2003

0530

2003

0614

2003

0626

2003

0705

2003

0717

2003

0726

2003

0807

2003

0816

2003

0828

2003

0906

2003

0918

2003

0930

2003

1012

2003

1021

2003

1102

2003

1111

2003

1123

2003

1202

2003

1214

2003

1223

Con

cent

ratio

n (u

g/m

3)88101 (PM2.5STN)88301 (Ammonium)88302 (Sodium)88303 (Pottasium)88305 (Organic Carbon)OC.B88306 (Nitrate)88307 (Elemental Carbon)EC.B88403 (Sulfate)Reconstructed Mass (k=1.4)Reconstructed Mass (k=2.4)

PM2.5 - Source Contribution Kim & Hopke Source Apportionment of Fine Particles in Washington, DC, Utilizing

Temperature-Resolved Carbon Fractions (AWMA Journal, July 2004)

Study based on PM2.5 data (1988-97) for Washington, DC

Mostly OC

Total Sulfate = 60%

PM2.5 - Source Contribution

Battelle & Sonoma Tech EIGHT-SITE SOURCE APPORTIONMENT OF PM2.5 SPECIATION TRENDS DATA (September 2003)

PM2.5 - Source Contribution

DRI Report 2005 Source Apportionment Analysis of Air Quality Monitoring Data: Phase II (DRI Report, March 2005)

Seasonal Variation PM2.5 Components DRI Report 2005

Source Apportionment Analysis of Air Quality Monitoring Data: Phase II (DRI Report, March 2005)

Seasonal & Daily Variation PM2.5 Mass DRI Report 2005

Source Apportionment Analysis of Air Quality Monitoring Data: Phase II (DRI Report, March 2005)

Conclusion PM2.5 Composition Highest daily PM2.5 levels Summer & Winter

PM2.5 composition Component Summer Winter Annual (2004) Organics 42% 50% 28%(Organic & Elemental Carbon)

Sulfate 40% 13% 58% Ammonium 12% 10% Nitrate 2% 19% 7%

Organic & Elemental Carbon and Sulfate are the main constituents of PM2.5 in Washington, DC PM2.5 non-attainment area.

Conclusion Source Contribution

Source Contribution (Battelle Study) Coal combustion 46% Motor vehicles 28%

Gasoline vehicles Major source of organic carbon (OC = ~21% of total PM2.5 mass, Kim, Hopke)

Road construction 9% Ammonium Nitrate 7% Canadian fire 7% Vegetative burning 3%

Conclusion Source Contribution

Source Contribution (DRI Study)Source Summer Winter

Ammonium sulfate 52% 32% Vegetative burning 24% 21% Ammonium nitrate 5% 19% Motor vehicle 9% 15% Diesel vehicle 1% 2% Coal fired power plant 3% 6%

Comparison of Emissions (2002 vs. 2009)

BY 2002

4% 1%

32%

36%

27% PM25-PRI

NH3

NOX

SO2

VOC

Annual PM2.5 Inventories(Washington DC-MD-VA PM2.5 NAA)

0

50000

100000

150000

200000

250000

PM25-PRI NH3 NOX SO2 VOC

Pollutants

Emis

sion

s (t

on/y

r)

BY 2002

AY 2009AY 2009

8% 3%

31%

12%

46%

PM25-PRI

NH3

NOX

SO2

VOC

Comparison of Emissions (2002 vs. 2009)

Annual PM2.5 Point Source Inventory (2002 vs. 2009)(Washington DC-MD-VA PM2.5 NAA)

0

50000

100000

150000

200000

250000

PM25-PRI NH3 NOX SO2 VOC

Pollutants

Emis

sion

s (t

on/y

r)

BY 2002

AY 2009

Annual PM2.5 Area Source Inventory (2002 vs. 2009)(Washington DC-MD-VA PM2.5 NAA)

0

10000

20000

30000

40000

50000

60000

70000

80000

90000

PM25-PRI NH3 NOX SO2 VOC

Pollutants

Emis

sion

s (t

on/y

r)

BY 2002

AY 2009

Annual PM2.5 Onroad Source Inventory (2002 vs. 2009)(Washington DC-MD-VA PM2.5 NAA)

01000020000300004000050000

60000700008000090000

100000

PM25-PRI NH3 NOX SO2 VOC

Pollutants

Emis

sion

s (to

n/yr

)

BY 2002

AY 2009

Annual PM2.5 Nonroad Source Inventory (2002 vs. 2009)(Washington DC-MD-VA PM2.5 NAA)

0

5000

10000

15000

20000

25000

30000

35000

PM25-PRI NH3 NOX SO2 VOC

Pollutants

Emis

sion

s (t

on/y

r)BY 2002

AY 2009

Area or Nonpoint Sources are the largest contributors of PM2.5-Pri emissions with road construction and residential wood burning emissions contributing the most.

ConclusionOrganic & Elemental Carbon and Sulfate are the main constituentsof PM2.5 in Washington, DC PM2.5 non-attainment area.

OC & EC are part of PM2.5-Pri emissions (emitted directly from sources). Sulfate forms due to oxidation of SO2 in the air and also due to reaction of SO2 with NH3 (Ammonium Sulfate).

Point sources are the largest contributors of PM2.5-Pri and SO2 emissions.

Area or Nonpoint Sources are the largest contributors of PM2.5-Pri emissions with road construction and residential wood burning emissions contributing the most.

NOx emissions from motor vehicles contribute significantly towards nitrate formation, an important constituent during winter.