1. Bill Martin Linda Kalnejais Mike Bothner
Contaminant Metals in Boston Harbor: Processes Influencing long-term fate
Bill Martin
Linda Kalnejais
Mike Bothner

2. Study Site:Hingham Bay 2000 - 2008

3. Ag, Pb, and Cu:

4. Cu, Ag, and Pb All are associated with organic matter : Cu > Ag, Pb
All form stable complexes and sparingly soluble solid phases
with S(-II)
All coprecipitate with / sorb to Fe oxides : Pb > Ag, Cu

5. Depth Distributions of Sedimentary Processes Hingham Bay Site
(not to scale)

6. Data Treatment: Averaged and smoothed profiles

7. Fe and S cycling
Winter

8. Fe and S cycling
Summer

9. Late Summer / Early Fall
Fe and S cycling
Late Summer / Early Fall

10. Trace Metal Cycling: Cu - Winter

11. Trace Metal Cycling: Cu - Summer

12. Trace Metal Cycling: Cu - Late summer

13. Compare: Cu and Ag

14. Compare: Cu and Pb

15. The sedimentary environment

16. Sediment Resuspension: Experimental Setup

17. Sediment Resuspension: Mass resuspended vs. bottom stress

18. Solid Phase Metals

19. Dissolved metals

20. Longer-term release from resuspended particles
Incubations:
Filled : particle incubations
Open: filtered controls

21. Bottom stress at the Hingham Bay Site

22. Including Sediment-Seawater exchange in the budget for Cu in Boston Harbor

23. Conclusions
Remobilization of contaminant metals, deposited earlier, may be a
significant source of metals to Boston Harbor.
Ongoing work:
Complete analyses and interpretation of Boston Harbor and Mass Bay
experiments.
To date:
Kalnejais (2005) - PhD Thesis
(and presentations at AGU, ASLO, GSA)
Oates (2008) MS Thesis
Morford et al. (2007)
Kalnejais et al. (2007)
Martin and Kalnejais (2007)
Future work:
Update and extend contaminant metal budgets for Boston Harbor
Determine distributions of particulate metals in Mass. Bay -
especially after important resuspension events