Source Apportionment of PM2.5 Speciation Trends Data Conducted by: Battelle (Basil Coutant) with

1. Source Apportionment of PM2.5 Speciation Trends Data Conducted by: Battelle (Basil Coutant) with Sonoma Tech. (Hillary Main) and Dyncorp (Katherine Brehme) Funded by: OAPQS, EMAD Summarized here by: Rich Poirot, VT DEC 9/27/02

2. Technical Approach • Techniques applied • PMF (UNMIX) to apportion PM2.5 into seven sources • local wind analysis to verify local sources • back trajectory analysis for transport, may miss local sources (500km start height, 3hr, 80km cells) • 3 Urban sites • St Louis, MO • Bronx, NY • Houston, TX • Limited amount of data (~1 year)

3. Bronx, NY – site attributes • Bronx Garden site • located in the middle of the Bronx • heavily populated urban area • local sources • mobile emissions • fuel oil (particularly in the winter) • two oil-fired power plants • street cleaning • marine influence

4. Source Number Preliminary Identification Notes Key Species and Profile Comments 1 Secondary (summer) sulfate Summer peak Key species include NH4, OC, SO4, mass. This is consistent with the regional background/transport sources observed in all SA analyses done in the Northeast. 2 Fuel oil Winter peak Key species include EC>OC, Cl, V, Ni. V and Ni, winter peak lead to fuel oil combustion. 3 Sea spray Note FRM/PM2.5 inconsistency Key species include Na, K, Cl, several metals. Odd profile with some indication of general industrial source. 4 Mobile - tire wear combination. Also inconsistent FRM, PM2.5. Key species include Na, OC>EC, several metals. Possible mobile source profile including tire wear. 5 Industrial? (Oil fired power plant ?) Winter peak Key species include Zn, Ca, Se, Ni, Pb, OC>EC. Winter peak. Note that the sulfur and V contributions are low while Zn, Pb, Cu, and Ca are enhanced. 6 Nitrate Winter peak Key species include K, NO3, NH4, mass. This is consistent with a regional nitrate signature. 7 Dirt Most likely from street cleaning Key species include K, Al, Ca, Si, Ti. Good match with paved road dust. Summary of Source Identification for Bronx, New York

5. Summary of Source Apportionment for Bronx Source Apportioned mass (g/m3) Back Trajectory Pollution Rose Notes Secondary sulfate 5.29 PA, Western VA, Eastern MA, Eastern WV, Atlantic Ocean Uniform Back trajectory is consistent with known source locations. Fuel oil 1.22 NY City and east, parts of VA, NC, and SC North, West, and South Basically consistent, the SC area may be from oil‑fired power plants. Sea spray 0.30 Atlantic ocean NE-SE Mobile-tire wear combination 2.49 NY, NY City, MA, CT, VA, PA East and SE Back trajectory is consistent with major highways. Industrial 1.82 Central OH, Southern PA, MD, NC-VA SW to NW Back trajectory is consistent with expected source locations. Nitrate 4.09 Central OH, PA, MD, NC, SC, ME SE, S to W Source location is uncertain. Dirt 0.97 Canada, NY City, Central PA down through VA, Mining areas of OH and WV SW, NNE, SSE Most likely street cleaning, other area correspond to farming and mining locations.

6. Relative Composition for Source 1 at the Bronx Site Sulfate Ammonium Organic Carbon Key species include NH4, OC, SO4, mass. This is consistent with the regional background/transport sources observed in all SA analyses done in the Northeast.

7. Source 1 - Secondary sulfate has a summer peak

8. Source contribution function for Source 1 at the Bronx site indicates - • sulfate sources in OH, WV, and PA near Wheeling, WV, a region running southwest through VA, area along Lake Erie, and area over Massachusetts. • corresponds to clusters of utility plants with large SO2 emissions.

9. Source 6 - Nitrate probability plots for Bronx site do not correspond nearly as well, • may be due to semi-volatile nature of nitrate, meteorological influence • indicate a source in SC, which corresponds to utility plant locations

10. St. Louis – site attributes • Blair Street site • located near the intersection of several highways • mobile emissions should be a major component • several municipal incinerators • zinc smelter • large lead smelter • steel mill • cement manufacturing • limestone quarrying in the area.

11. Source Number Preliminary Identification Notes Key Species and Profile Comments 1 Zinc refinery Facility near the site (and several municipal waste incinerators) Cl, Zn, EC>OC. 2 Copper Smelting Chemetco (secondary copper smelter in Alton, Illinois) Cu combined with OC, EC 3 Coal combustion Consistent with power generation. Does not show a seasonal trend. Mass, OC, NH4, SO4, Se. 4 Steel production Grant City Steel may contribute to high Fe levels. Cl, Cr, Fe, Mn, Ni. Good match with profile. 5 Nitrate NOx from power plants. Power plant to the SE Key species include NO3, mass, NH4. 6 Crustal High Ca, K relative to typical crustal. Possibility cement plant or limestone quarrying, but peaks probably coincide with agricultural activity. Al, Si, Good match to crustal profile. 7 Mobile sources High Pb possible because of residue (in road dust) from old Pb smelter emissions and hauling w/o tarps. Br, OC>EC, Pb. Summary of Source Identification for St. Louis, Missouri

12. Source Apportioned mass (g/m3) Back Trajectory Pollution Rose Notes Zinc 0.85 IL, KY, Western TN N-NNW and SE Granite City IL steel production is too close to be indicated by the back trajectories. Copper Smelting 0.59 All distant, Central TX-OK, KS, NE NE-SE The Alton IL cooper smelter is too close to be indicated by the back trajectories. Coal combustion 5.74 OH River, WV, OH, IN, KY, TN, AR, MS Uniform Locations are consistent with known sources. Steel production 0.76 OH River, N IN, TX, AR-TN-MS, Atlanta NE-E Granite City Steel is too close to be indicated by the back trajectories. Nitrate 5.02 Atlanta, OH River and NW Northerly Source location is unknown due to confounding factors. Crustal 1.43 Central MO-AR-N LA-NW TX-W OK S-SW Most likely from agricultural activities. Mobile sources 2.92 Distant Uniform The local mobile sources should dominate and are too close to be indicated by the back trajectories. Summary of Source Apportionment for St. Louis

13. St Louis - Coal Combustion (Sulfate) • - notice the direction of the curl on the trajectories from the 20 percent worst days (red) for the sulfate source that pass through Kentucky • source contribution plot may be indicating sulfate sources in Kentucky because of these trajectories around high pressure (indicated by clockwise wind flow). • results in pollutants trapped near the surface. • not surprising that source areas are indicated to the south of the utility plants along the Ohio River and along the Indiana‑Illinois state line

14. St Louis - Nitrate • On the other hand…. • high nitrate days are on days with winds out of Canada (red). • association with these winds is probably not indicating source locations, but rather conditions favorable for the nitrate (cool temperatures?).

15. Houston – site attributes • Aldine Road site • heavily impacted by the ship channel • expected to be affected by sources that would be associated with an urban area • i.e., mobile emissions should be significant

16. Source Number Preliminary Identification Notes Key Species and Profile Comments 1 Dirt Usual crustal elements. 2 Fireworks The peak is for July 4. July 5 is about half-way down. Key species include K. Other small blips of this profile in the winter may be consistent with wood smoke. 3 Industrial Key species include Zn, Cl, Cr, Ni, other metals. Other profiles to consider include hogged fuel boiler, industrial average manufacturing. 4 Secondary OC/mobile This site is in a residential neighborhood with freeways to the north. Key species include OC>EC, NH4, Ca, Mass. 5 Marine - Nitrate source Inconsistent profile – the mass estimate is too low – sulfur/sulfate do not match up well. Key species include NO3, Na, Cl. This could be a marine influenced profile from the gulf or bay on which sodium nitrate has formed as the air parcels pass over the emissions sources. That would explain the absence of ammonium and sulfur. 6 Mobile/Mn source The Mn signature may be a result of substituting MDL/2 for Mn. Key species include Mn. 7 Secondary sulfate from fossil fuels This appears to be a general combustion signature including oil (V) and coal (Se). Se from coal combustion is a possibility as Texas Lignite operates upwind of Houston. Summary of Source Identification for Houston, Texas

17. Source Apportioned mass (g/m3) Back Trajectory Pollution Rose Notes Dirt 0.77 Local/Met related S-W Fireworks 0.49 Local/Met related W-NW This is essentially a one‑time, local source. Industrial 0.87 Local/Met related East-South Secondary OC/mobile 5.19 Local/Met related Northerly Marine‑Nitrate source 0.29 Local/Met related SE and NW The bi-directionality could be from a sea breeze effect. Mobile‑Mn source 1.04 Local/Met related SE and NW The bi-directionality could be from a sea breeze effect. Secondary sulfate from fossil fuels 5.54 Local/Met related Slightly E-SE The pollution rose and back trajectories are not consistent. Summary of Source Apportionment for Houston

18. Houston – Secondary Sulfate • associated with clockwise airflow • associated with high‑pressure zones rather than an area • virtually all trajectories enter from the southeast, over the shipping channel • source contribution function is always lower than would be expected for a source location 

19. Houston – Marine Nitrate • Associated with airflow from the Gulf and airflow out of Canada (red). • As with the other sites, the flow out of Canada is probably just associated with conditions favorable to nitrate formation. Flow over the Gulf explains the marine component of the profile. • Source contribution function is very low, which may indicate that the sources are local or, more likely, the relationship is from favorable meteorological conditions.

20. Conclusions • Combination of source apportionment techniques, local wind analysis, and back trajectory analysis provides meaningful results. • Limitations – • Sufficient data • Local low level winds, highly variable • Back trajectories – coarse resolution, may miss local sources • Lack of error estimates • Next Steps – add DC and Milwaukee sites