High Time Resolution PM 10 Metals by the CES Ambient Metals Monitor (Xact 620):

Transcription

1 High Time Resolution PM 1 Metals by the CES Ambient Metals Monitor (Xact 62): Field Performance Evaluation and Data Trends for St. Louis Varun Yadav, JAY TURNER Washington University in St. Louis Jerry Downs, Terry Rowles Missouri Department of Natural Resources A&WMA 29 Annual Conference and Exhibition Detroit, Michigan June 16, 29

2 Motivation The St. Louis Community Air Project (CAP) identified six hazardous air pollutants of concern including arsenic, however poor data quality for PM 2.5 arsenic from speciation network data PM 1 air toxics metals routinely measured at only one site 2

3 Objectives Community Air Toxics Grant from USEPA Phase I [Paper #37] four site network of HiVol PM 1 samplers one year at 1-in-3 days hot acid extraction and analysis by ICP-MS ~2x urban excess for arsenic Phase II [Paper #146] high(er) time resolution measurements six one-month deployments of CES Xact 62 Xact performance evaluation 3

4 Cooper Environmental Services (CES) Xact 62 particle collection on a filter tape analysis by x-ray fluorescence (XRF) continuous data time series at user-defined intervals MDNR instrument optimized for As, Hg, and Pb at remote areas 4

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6 Optimizing the Sampling Time Interval 1 depends on study objectives! trade-offs between time resolution and frequency above MDL Blair Street (STL) 1-hour: 56%>MDL 2-hour: 86% > MDL c MDL, ng/m 3 arsenic sampling time = analysis time (Xact operation) 15 minutes sampling time, various analysis times 2x sampling time = 2x deposit mass 2x analysis time = 1.4x counting sensitivity analysis time, hrs 6

7 Xact Performance Evaluation HiVol PM 1 / quartz filter, NATTS digestion protocol ICP-MS: As, Pb, Se LowVol PM 1 (FRM) / Teflon filter XRF: Ca, Fe, K, Mn, Pb, Ti 7

8 Xact vs. LowVol PM 1 FRM / XRF Titanium Potassium 1 35 m 3 18-hour avera age Xact, ng/m Xact = (1.5 ±.4) filter + (-2.2 ± 2.8) m 3 18-hour avera age Xact, ng/m Xact = (.84 ±.21) filter + (28 ± 25) hour integrated filter with offline XRF, ng/m 3 18-hour integrated filter with offline XRF, ng/m 3 K: narrow dynamic range, regression misleading 8

9 Xact vs. LowVol PM 1 FRM / XRF Manganese Lead Xact = (1.2 ±.1) filter + (-.1 ± 1.8) 18-hour averag ge Xact, ng/m m 3 18-hour avera age Xact, ng/m Xact = (1.46 ±.18) filter + (.7 ± 1.6) hour integrated filter with offline XRF, ng/m 3 Mn: biased but highly correlated hour integrated filter with offline XRF, ng/m 3 9

10 Xact vs. LowVol PM 1 FRM / XRF Selenium Arsenic 8 8 m 3 18-hour avera age Xact, ng/m m 3 18-hour avera age Xact, ng/m hour integrated filter with offline XRF, ng/m 3 18-hour integrated filter with offline XRF, ng/m 3 1

11 Selenium: Xact vs. Filter-Based Measurements Xact vs. LowVol filter / lab XRF Xact vs. HiVol filter / lab ICP-MS hour aver rage Xact, ng/ /m selenium, 24-h hour average Xa act, ng/m 3 PM Blair Arnold hour integrated filter with offline XRF, ng/m 3 Xact = (1.15 ±.1) filter + (-.4 ±.89) PM 1 selenium, 24-hour integrated filter, ng/m 3 11

12 Arsenic Methods Comparisons 8 Collocated HiVol Samplers Blair site, 4 th Quarter 28 8 Xact vs. WUSTL HiVol Dec 28 / Jan 29 m 3 analysis, ng/m NATTS / ERG hour averag ge Xact, ng/m MDNR/WUSTL analysis, ng/m 3 24-hour integrated HiVol PM 1, ng/m 3 12

13 Xact Monitoring Sites MISSOURI ILLINOIS 13

14 PM 1 Lead by Xact (2-hour resolution) BLAIR ARNOLD wind direction, o N wind direction, o N PM 1 lead, ng/m 3 PM 1 lead, ng/m 3 Dashed line is bearing of Doe Run Herculaneum lead smelter 14

15 PM 1 Arsenic by Xact (2-hour resolution) 36 BLAIR excludes one record 36 ARNOLD direction, o N direction, o N wind 135 wind PM 1 arsenic, ng/m 3 PM 1 arsenic, ng/m 3 15

16 PM 1 Arsenic at Blair by Xact (2-hour resolution) wind direction vs. concentration 36 excludes one record 315 nonparametric wind regression direction, o N ng/m 3 wind PM 1 arsenic, ng/m 3 16

17 PM 1 Arsenic at Blair for Winds from Northwest 36 excludes one record wind direction, o N PM 3 1 arsenic, ng/m red markers = 8 AM 6PM weekdays 17

18 PM 1 Arsenic at Blair for Winds from Northwest? Emission source zone of influence? Monitor zone of representation? 18

19 The Next Steps Additional Xact deployments currently on fifth of six deployments Expanded performance evaluation additional low-volume PM 1 FRM samples, analysis by XRF and ICP-MS Collocated Xact measurements (MDNR and CES) Herculaneum, August 29 crucial data for receptor modeling Receptor modeling of the data sets 19

20 Acknowledgements Missouri Department of Natural Resources Jim Brunnert, Celeste Koon, Will Wetherell Cooper Environmental Services John Cooper, Krag Petterson U.S. EPA / Office of Research and Development Teri Conner, Gary Norris, Bob Willis Washington University Stephen Feinberg 2

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