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GMU Chemistry & Biochemistry PCBs and PAHs in the Anacostia River: Sampling, Concentrations and Transport in 2004-2005 Gregory D. Foster & Phillip R. McEachern.

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Presentation on theme: "GMU Chemistry & Biochemistry PCBs and PAHs in the Anacostia River: Sampling, Concentrations and Transport in 2004-2005 Gregory D. Foster & Phillip R. McEachern."— Presentation transcript:

1 GMU Chemistry & Biochemistry PCBs and PAHs in the Anacostia River: Sampling, Concentrations and Transport in 2004-2005 Gregory D. Foster & Phillip R. McEachern Department of Chemistry & Biochemistry George Mason University Fairfax, VA

2 GMU Chemistry & Biochemistry Comparison of tPCB concentrations in sediments Highest levels occur in Anacostia River Baltimore Harbor Data compiled by J Baker (CBL)

3 GMU Chemistry & Biochemistry Study Objectives Develop automated sampling techniques to accurately measure concentrations of PCBs and PAHs in the Anacostia River and refine annual load estimates Identify mode of PCB/PAH transport in AR and develop correlations with hydrology

4 GMU Chemistry & Biochemistry 1 2 USGS Gauging Stations 1. NE Branch sfc ar: 186 km 2 Q avg :1.2x10 8 m 3 /y 2. NW Branch sfc ar: 126 km 2 Q avg :7.0X10 7 m 3 /y Watershed is ~50% urban land use ~80% urbanized in lower portion

5 GMU Chemistry & Biochemistry PCB Geochemistry: Dissolved and Particle Phases Geosolids: Alumino- silicate clay particles in water (TSM) PCBs are concentrated in geosolids through sorption Sorbed PCB (C p ng/L) Dissolved PCB (C w ng/L)

6 GMU Chemistry & Biochemistry

7 GMU Chemistry & Biochemistry Time, min Response GC-ECD Chromatogram of PCBs 56 single component peaks (HP-1, 30 m) 16 multiple component (2+) peaks 88 congeners in 72 peaks Congener No. (e.g., 119) tPCBs = sum of mass Homologue groups LOD ~0.1 ng/L

8 GMU Chemistry & Biochemistry Fluorene Phenanthrene Anthracene Fluoranathene Pyrene Benz(a)anthracene Chrysene Benzo(b)fluoranthene Benzo(k)fluoranthene Benzo(a)pyrene Indeno(cd)pyrene Benzo(ghi)perylene Dibenz(ah)anthracene Time Intensity GC/MS TIC Chromatogram Anacostia River Sediments Foster et al. (2000) Appl Geochem, 15,901 16 Priority Pollutant PAHs LOD ~ 0.5 ng/L

9 GMU Chemistry & Biochemistry Automated River Sampling

10 GMU Chemistry & Biochemistry NE Branch of the Anacostia River How do you sample a river?

11 GMU Chemistry & Biochemistry

12 GMU Chemistry & Biochemistry River sampling was initiated when rain gauge >0.15-0.25 in/hr

13 GMU Chemistry & Biochemistry

14 GMU Chemistry & Biochemistry

15 GMU Chemistry & Biochemistry

16 GMU Chemistry & Biochemistry Examples of Sampled Hydrographs

17 GMU Chemistry & Biochemistry H o: samplers equal (TSM) p>0.05 (accept) paired t test TSM: Fultz v. Isco Sampling NE Branch

18 GMU Chemistry & Biochemistry TSM: Fultz v. Isco Sampling NW Branch NA H o: samplers equal (TSM) p>0.05 (accept) paired t test

19 GMU Chemistry & Biochemistry H o: samplers equal (D+P) p>0.05 (accept) paired t test PCBs: Fultz v. Isco Sampling - D+P NE Branch

20 GMU Chemistry & Biochemistry PCBs: Fultz v. Isco Sampling - D+P NW Branch H o: samplers equal (D+P) p>0.05 (accept) paired t test

21 GMU Chemistry & Biochemistry PAHs: Fultz v. Isco Sampling - D+P NE Branch H o: samplers equal (D+P) p>0.05 (accept) paired t test

22 GMU Chemistry & Biochemistry H o: samplers equal (part) p>0.05 (accept) paired t test PAHs: Fultz v. Isco Sampling - D+P NW Branch

23 GMU Chemistry & Biochemistry PCBs & PAHs in Anacostia River Water NE & NW Branches

24 GMU Chemistry & Biochemistry Summary of tPCB Concentrations H o : base and storm flow [tPCBs] are equal p<0.05 (reject) Median Concentrations  range (min-max)

25 GMU Chemistry & Biochemistry NE Br Base- and Storm Flow tPCBs

26 GMU Chemistry & Biochemistry NW tPCBs

27 GMU Chemistry & Biochemistry 61% (54) of PCB congeners detected in >80% of NE samples

28 GMU Chemistry & Biochemistry >85% of tPCB Mass Associated 54 Major Congeners

29 GMU Chemistry & Biochemistry PCB Homologue Distribution NE Branch Dissolved: 4>5>6>3>7>8>9>10 Particle: 5>4>6>7>8>3>9>10

30 GMU Chemistry & Biochemistry PCB Homologue Distribution NW Branch Dissolved: 4,5>3>6>7>8>9>10 Particle: 4>5>6>3>7>8>9>10

31 GMU Chemistry & Biochemistry Aroclor Homologue Profiles v. NE Branch % Rel Abundance

32 GMU Chemistry & Biochemistry Median [tPCBs], ng/L LBD12 Hickey11 Watts 6 Clay St.22 PEPCO23 WNY10 Diss + Part tPCB Concentrations (m/V)

33 GMU Chemistry & Biochemistry Summary of tPAH Concentrations H o : base and storm flow [tPAHs] are equal p<0.05 (reject) Median Concentrations  range (min-max)

34 GMU Chemistry & Biochemistry Base Flow Storm Flow NE Br Base- and Storm Flow tPAHs

35 GMU Chemistry & Biochemistry Conclusions Particles in storm flows represent greatest PCB/PAH inputs PCBs/PAHs in dissolved phase of river water are relatively constant among flow regimes PCB/PAH hotspots are likely derived from storm flow inputs near outfalls and up small tribs in urbanized subsheds

36 GMU Chemistry & Biochemistry Acknowledgements Technical: David Velinsky, Hyun-Min Hwang, Cherie Miller, Tom Huff Students: Eldon Roberts, Robert Allen, Phil McEachern Collaborators: OWML, Appl Environ, USGS, MWCOG, MDE Sponsors: CBPO/EPA, AWTA, MWCOG, Jeffress Mem Trust, MDE


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