1. Fairbanks PM 2.5 Source Apportionment Using the Chemical Mass Balance (CMB) Model Tony Ward, Ph.D. The University of Montana Center for Environmental Health Sciences January 10, 2012

2. Goal of the Fairbanks CMB Project Complement the PM 2.5 source apportionment work already completed with additional analytical and modeling strategies. 1) Chemical Mass Balance (CMB) modeling. 2) 14 C. 3) Chemical markers of wood smoke.

3. Fairbanks CMB Sampling Program Four sites, including: 1) State Office Building. 2) Peger Road. 3) North Pole. 4) RAMS Mobile site. Met One Spiral Ambient Speciation Sampler (SASS) at each site. Sampling every 3 days during winters of 2008/2009, 2009/2010, and 2010/2011. 24-hour (midnight to midnight).

4. 1)Teflon Filter* Mass Elements (36) 3) Quartz Filter* OC/EC 4) Quartz Filter 2) Nylon Filter* Ions (5) 14 C Univ Arizona Levoglucosan Univ Montana PM 2.5 Speciation Analyses *Analyzed by Research Triangle Institute.

5. CMB Modeling EPA CMB receptor model, Version 8.2 was used to apportion the sources of PM 2.5 at each of the sites. CMB model inputs 1) Ambient PM 2.5 concentrations and uncertainties -mass -elements -ions -OC/EC 2) Sources of PM 2.5 (source profiles) in the airshed.

6. CMB Model The CMB model consists of a solution to linear equations that expresses each receptor chemical concentration as a linear sum of products of source fingerprint abundances and contributions. where C i is the ambient concentration of specie i, a ij is the fractional concentration of specie i in the emissions from source j, S j is the total mass concentration contributed by the source.

7. Fairbanks Source Profiles Street sand and road dust. Pure secondary emissions (SO 4, (NH 4 ) 2 SO 4, NH 4 NO 3 ). Gasoline and diesel exhaust emissions. Tire and brake wear. Wood combustion (residential, fireplaces, slash, prescribed). Meat cooking. Distillate oil / residual oil combustion. Taken from SPECIATE 4.0 and a Missoula CMB source library.

8. 14 C – University of Arizona Samples were analyzed by the Accelerator Mass Spectrometry (AMS) Laboratory at The University of Arizona. If 14 C is present at atmospheric levels, the molecule must derive from a recent plant product. If a molecule contains no detectable 14 C, it must derive from a petrochemical or some other ancient source. Results from this analysis will enable us to calculate the % wood smoke component of the PM 2.5.

9. Chemical Markers of Wood Smoke Known molecular marker for biomass combustion. Analysis performed with a method developed at UM. Levoglucosan

10. Results

11. PM 2.5 Speciation Results Out of the 36 elements quantified, only 14 were consistently measured at or above their reported MDLs. Sulfur had the highest concentration of the measured elements, with the highest overall program levels measured at the State Building site. Sulfate had the highest concentration of any of the measured ions, while TC was heavily enriched with OC.

12. State Building CMB Results (November 11, 2008 – April 7, 2009)

13. State Building Site Season:Winter 2008/2009Winter 2009/2010Winter 2010/2011 Dates:11/8/08-4/7/0911/3/09-3/15/1011/1/10-2/8/11 CMB Source Estimates (ug/m 3, and % of Total PM 2.5 Measured) Sulfate5.1 (20.0 %)5.2 (18.1 %)3.5 (17.3 %) Ammonium Nitrate2.1 (8.1 %)2.5 (8.9 %)1.7 (8.4 %) Diesel0.3 (1.1 %)0.6 (2.2 %)None Detected Automobiles1.7 (6.8 %)0.7 (2.5 %)0.4 (1.9 %) Wood smoke16.0 (63.1 %)19.5 (67.8 %)14.6 (72.4 %) Unexplained0.2 (0.8 %)0.2 (0.6 %)0.04 (0.02 %) PM 2.5 Mass (ug/m3)25.328.820.2

14. North Pole CMB Results (January 25, 2009 – April 7, 2009)

15. North Pole Site Season:Winter 2008/2009Winter 2009/2010Winter 2010/2011 Dates:1/25/09-4/7/0911/3/09-3/15/101/9/11-2/5/11 CMB Source Estimates (ug/m 3, and % of Total PM 2.5 Measured) Sulfate1.9 (9.8 %)2.6 (7.8 %)2.1 (8.0 %) Ammonium Nitrate1.0 (5.1 %)1.2 (3.6 %)0.9 (3.5 %) Diesel0.2 (0.8 %)0.8 (2.5 %)0.9 (3.4 %) Automobiles0.7 (3.7 %)1.3 (3.8 %)1.4 (5.1 %) Wood smoke15.0 (79.8 %)27.1 (81.2 %)21.3 (79.4 %) Unexplained0.2 (0.8 %)0.3 (1.0 %)0.2 (0.6 %) PM 2.5 Mass (ug/m3)18.933.726.8

16. RAMS CMB Results (January 25, 2009 – April 7, 2009 )

17. RAMS (Mobile) Site Season:Winter 2008/2009Winter 2009/2010Winter 2010/2011 Dates:1/25/09-4/7/0911/15/09-3/15/10No Sampling. CMB Source Estimates (ug/m 3, and % of Total PM 2.5 Measured) Sulfate1.1 (13.0 %)4.0 (10.9 %)No Sampling. Ammonium Nitrate0.9 (10.5 %)0.9 (2.5 %)No Sampling. DieselND2.5 (6.8 %)No Sampling. AutomobilesND2.3 (6.2 %)No Sampling. Wood smoke6.3 (76.0 %)26.9 (73.5 %)No Sampling. Unexplained0.04 (0.5 %)0.04 (0.1 %)No Sampling. PM 2.5 Mass (ug/m3)8.236.7No Sampling.

18. Peger Road CMB Results (January 25, 2009 – April 7, 2009)

19. Peger Road Site Season:Winter 2008/2009Winter 2009/2010Winter 2010/2011 Dates:1/25/09-4/7/0911/3/09-3/15/101/9/11-2/5/11 CMB Source Estimates (ug/m 3, and % of Total PM 2.5 Measured) Sulfate2.8 (16.7 %)4.8 (16.5 %)4.8 (16.6 %) Ammonium Nitrate1.5 (8.9 %)2.1 (7.4 %)2.0 (7.1 %) Diesel1.2 (7.3 %)2.8 (9.6 %)0.8 (2.9 %) Automobiles0.7 (3.9 %)0.4 (1.3 %)0.7 (2.5 %) Wood smoke10.6 (62.7 %)18.6 (64.4 %)20.2 (70.6 %) Unexplained0.1 (0.5 %)0.3 (0.9 %)0.1 (0.3 %) PM 2.5 Mass (ug/m3)16.829.028.6

20. Wood smoke (CMB and 14 C) Winter 2008/2009Winter 2009/2010Winter 2010/2011 State BuildingCMB: 63.1 %CMB: 67.8 %CMB: 72.4 % 14 C: % PM 2.5 from wood smoke 47.2-56.9 % n=8 69.3 – 83.5% n=8 56.4 % - 67.9% n=7 North PoleCMB: 79.8 %CMB: 81.2 %CMB: 79.4 % 14 C: % PM 2.5 from wood smoke 49.7 – 59.9 % n=2 72.3 – 87.1 % n=8 77.8 – 93.8 % n=7

21. Wood smoke (CMB and 14 C) Winter 2008/2009Winter 2009/2010Winter 2010/2011 RAMSCMB: 76.0 %CMB: 73.5 %No Sampling. 14 C: % PM 2.5 from wood smoke 44.1 – 53.2 % n=2 None n=0 None Peger RoadCMB: 62.7 %CMB: 64.4 %CMB: 70.6 % 14 C: % PM 2.5 from wood smoke 27.1 – 32.6 % n=1 52.8 - 63.7 % n=8 47.2 – 56.9 % n=7

22. Summary Wood smoke (likely residential wood combustion) was the major source of PM 2.5 during the winter months, contributing 60% - 80% PM 2.5. 14 C and levoglucosan findings confirm these results. 14 C results showed that an average of 45-90% of the measured ambient PM 2.5 came from a wood smoke source.

23. Summary Secondary sulfate another large component: 10- 20% of PM 2.5 mass. Need to investigate this fraction more (chemical marker work with Chris Palmer).

24. Next Steps CMB modeling (as well as 14 C and levoglucosan analyses) for the winter of 2011/2012. CMB modeling for past years (2005/2006, 2006/2007, and 2007/2008). Utilize more representative profiles for Fairbanks wood burning, coal burning, and residential fuel oil combustion in CMB models.

25. Thank you. Questions?