1. MRPO Nitrate and Organic Speciation Special Studies Donna Kenski National RPO Technical Meeting Dallas, Dec. 3-4, 2002

2. Bondville Seney

5. Key Components at Bondville Dasgupta monitor: measures gaseous nitric acid, sulfur dioxide, and ammonia (estimated limits of detection 10, 15 and 100 parts per trillion by volume, respectively) for a 15 min period, and then particulate nitrate, sulfate, and ammonium for the next 15 min period. Photolytic (true) NO 2 and NO y Collocated gravimetric PM2.5, continuous PM2.5, speciated 24-hour PM2.5, continuous EC/OC, ozone, and meteorology (temperature, relative humidity, wind speed and direction, precipitation). 24-hour and 6-hour denuder samples

6. More detail on Dasgupta PM2.5 size selector Particles collected by humidification Gases collected by wet denuder Both particles and gases analyzed by IC Ammonia/ammonium analyzed in separate detector, using porous membrane and conductivity detector

7. Current Status and Schedule Dasgupta, NO2, Noy will be deployed in January, 2003 Sampling to continue for at least one calendar year Challenges: wintertime measurements with wet denuders, full time use of instruments usually used in shorter-term studies

8. Particle collector

10. What will we learn? What controls the formation of nitrate: HNO 3 or NH 3 : –HNO 3 (g) + NH 3 (g) --> NH 4 NO 3 (s) What effect will reductions in SO 2 and SO 4 have on NH 4 NO 3 : additional NH 4 available from SO 2 reductions could increase NH 4 NO 3 Diurnal variations in HNO 3 and NH 4 may lead to answers about sources

11. Indicator Species Excess Ammonia (Blanchard, et al, 2000) and Gas Ratio (Ansari and Pandis, 1999) Excess AmmoniaGas Ratio EA < 0NH3-limited EA > 0.1HNO3-limited GR < 0.4NH3-limited GR > 1.5HNO3-limited

13. Organic Carbon at Seney Organic matter can account for 50% or more of particle mass in summer at Seney NWR, Boundary Waters, and other remote pristine sites. Origin of OCM not obvious: –transported urban pollution –local biogenic –local and/or transported forest fires –other?? Source apportionment of IMPROVE data isn’t definitive (but efforts continue), hampered by too few species, degraded air far from sources, similarities among combustion sources (for quantified species).

14. Seney NWR, Michigan

16. What is organic speciation? Method developed by Glen Cass, Jamie Schauer, many others Quartz filters, XAD-coated denuders, or PUF cartridges can be analyzed Filters extracted with hexane, then benzene/2-propanol, split, one fraction derivatized (to convert organic acids to methyl esters for GC/MS identification), and both fractions analyzed by GC/MS 100s of species can be identified, some unique tracers of sources: –resin acids for soft wood combustion –syringols for hard wood combustion –levoglucosan for wood combustion –cholesterol for meat cooking –hopanes and steranes for diesel combustion

17. Sampling plan for Seney NWR PI: Jamie Schauer at UW-Madison Quartz filters collected at Seney (2/3 day) will be composited by month and analyzed for particle phase organic species for Jan ‘02 - Dec ‘02 period Source apportionment will be conducted based on tracer species Additional daily high-volume samples were collected and a subset of those will be analyzed and apportioned Selected molecular markers will be analyzed for single-compound carbon isotope ratios Interim report due Jan. 1 2003, final Nov. 1 2003