Mercury Geochemistry in Wetland and its Implications for In Situ Remediation
Publication: Journal of Environmental Engineering
Volume 128, Issue 8
Abstract
The objective of this study was to characterize the nature of Hg sorption to a wetland sediment with the intent of providing guidance for the selection of an appropriate in situ remediation strategy. Total Hg concentrations in the sediments were as high as 10 mg/kg, whereas associated pore water Hg concentrations were below detection, mg/L. Sediment Hg was not in an exchangeable form, and % of it was associated with organic matter. The remainder of the Hg was strongly associated with Fe oxides and/or with a precipitated phase, presumably a sulfide. Sediment Hg concentrations were significantly correlated with Fe oxide concentrations. Thermodynamic calculations based on field Eh/pH measurements and laboratory results suggest that under present field conditions metacinnabar (HgS) would not be stable due to the relatively low pH (∼4.2) and sulfate concentrations (0.14 mM) and high Eh levels at the study site. However, these calculations indicate that metacinnabar may have formed when the Hg first entered the wetland at elevated concentrations (∼5 mg/L). Given the ecologically sensitive nature of the wetland and the fact that the Hg is strongly bound to the sediment, it was concluded that a monitored natural attenuation approach for site remediation may be appropriate.
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References
Allison, J. D., Brown, D. S., and Gradac, K. J. (1991). “MINTEQA2/PRODEFA2, a geochemical assessment model for environmental systems: Version 3.0 users manual.” Rep. No. EPA/600/3-91/021, U.S. Environmental Protection Agency, Washington, D.C.
Baas-Becking, L. G. M., Kaplan, I. R., and Moore, D.(1960). “Limits of the natural environment in terms of pH and oxidation-reduction potentials.” J. Geol., 68, 243–284.
Bartlett, R., and James, B.(1980). “Studying dried, stored soil samples—some pitfalls.” Soil Sci. Soc. Am. J., 44, 721–724.
Beijer, K., and Jernelov, J. (1979). “Methylation of mercury in aquatic environments.” The biogeochemistry of mercury in the environment, J. O. Nriagu, ed., Elsevier/North-Holland Biomedical Press, Amsterdam, 203–210.
Benes, P., and Havlik, B. (1979). “Speciation of mercury in natural waters.” The biogeochemistry of mercury in the environment, J. O. Nriagu, ed., Elsevier/North-Holland Biomedical Press, Amsterdam, 176–202.
Cleam, V., and Gamble, D. S.(1974). “Metal–fulvic acid chelation equilibrium in aqueous Na solutions: Hg(II), Cd(II), and Cu(II) fulvate complexes.” Can. J. Soil Sci., 54, 413–417.
Garland, T. R., and Wildung, R. E. (1974). “Seasonal distribution of mercury in water, suspended matter and sediments of the lower Columbia River Watershed.” Rep. No. BNWL-SA-5194, Pacific Northwest National Laboratory, Richland, Wash.
Gilmour, C. C., Henry, E. A., and Mitchell, R.(1992). “Sulfate stimulation of mercury methylation in freshwater sediments.” Environ. Sci. Technol., 26, 2281–2287.
Hurley, J. P.et al. (1995). “Influences of watershed characteristics on mercury levels in Wisconsin rivers.” Environ. Sci. Technol., 29, 1867–1875.
Kaplan, D. I., Knox, A. S., Hinton, T. G., Sharitz, R. R., Allen, B. P., and Serkiz, S. M. (2001). “Proof-of-concept of the phytoimmobilization technology for TNX Outfall Delta.” Rep. No. WSRC-TR-2001-00032, Rev. 0, Westinghouse Savannah River Co., Aiken, S.C.
Loeppert, R. H., and Inskeep, W. P. (1996). “Iron.” Methods of soil analysis, part 3, chemical methods, D. L. Sparks, ed., Soil Science Society of America, Inc., Madison, Wis., 639–664.
Miller, W. P., Martens, D. C., Zelazny, L. W., and Kornegay, E. T.(1986). “Forms of solid phase copper in copper-enriched swine manure.” J. Environ. Qual., 15, 69–72.
Miller, W. P., and Miller, D. M.(1987). “A micro-pipette method for soil mechanical analysis.” Commun. Soil Sci. Plant Anal., 18, 1–15.
Nelson, D. W., and Sommers, L. E. (1996). “Total carbon, organic carbon, and organic matter.” Methods of soil analysis, part 3, chemical methods, D. L. Sparks, ed., Soil Science Society of America, Inc., Madison, Wis., 961–1010.
Pak, K. R., and Bartha, R.(1998). “Mercury methylation and demethylation in anoxic lake sediments and by strictly anaerobic bacteria.” Appl. Environ. Microbiol., 64, 1013–1017.
Paquette, K. E., and Helz, G. R.(1997). “Inorganic speciation of mercury in sulfidic waters: The importance of zero-valent sulfur.” Environ. Sci. Technol., 31, 2148–2153.
Patrick, W. H., Gambrell, R. P., and Faulkner, S. P. (1996). “Redox measurements of soils.” Methods of soil analysis, part 3, chemical methods, D. L. Sparks, ed., Soil Science Society of America, Inc., Madison, Wis., 1255–1274.
Rhoades, J. D. (1996). “Salinity: Electrical conductivity and total dissolved solids.” Methods of soil analysis, part 3, chemical methods, D. L. Sparks, ed., Soil Science Society of America, Inc., Madison, Wis, 417–436.
Schuster, E.(1991). “The behavior of mercury in soil with special emphasis of complexation and adsorption processes—A review of the literature.” Water, Air, Soil Pollut., 56, 667–680.
Specht, W. L. (1999). “Results of toxicity tests and chemical analyses conducted on sediment collected from the TNX Outfall Delta operable unit.” Rep. No. WSRC-TR-99-00380, Westinghouse Savannah River Co., Aiken, S.C.
St. Louis, V. L., Rudd, J. W. M., Kelly, C. A., Beaty, K. G., Bloom, N. S., and Flett, R. J.(1994). “Importance of wetlands as sources of methyl mercury to boreal forest ecosystems.” Can. J. Fish. Aquat. Sci., 51, 1065–1076.
Stumm, W., and Morgan, J. J. (1981). Aquatic chemistry: An introduction emphasizing chemical equilibria in natural waters, Wiley-Interscience, New York.
Sumner, M. E., and Miller, W. P. (1996). “Cation exchange capacity and exchange coefficients.” Methods of soil analysis, part 3, chemical methods, D. H. Sparks, ed., Soil Science Society of America, Inc., Madison, Wis, 1201–1229.
Wallschlager, D., Desai, M. V. M., Spengler, M., Windmoler, C. C., and Wilken, R.(1998a). “How humic substances dominate mercury geochemistry in contaminated floodplain soils and sediments.” J. Environ. Qual., 27, 1044–1054.
Wallschlager, D., Desai, M. V. M., Spengler, M., Windmoler, C. C., and Wilken, R.(1998b). “Mercury speciation in floodplain soils and sediments along a contaminated river transect.” J. Environ. Qual., 27, 1034–1044.
WSRC. (1999). “RFI/RI with BRA for the TNX outfall delta, lower discharge fully and swamp operable unit.” Rep. No. WSRC-RP-98-4158, Westinghouse Savannah River Co., Aiken, S.C.
Yin, Y., Allen, H. E., Huang, C. P., and Sanders, P. F.(1996). “Adsorption/desorption isotherms of Hg(II) by soil.” Soil Sci., 162, 35–45.
Information & Authors
Information
Published In
Journal of Environmental Engineering
Volume 128 • Issue 8 • August 2002
Pages: 723 - 732
Copyright
Copyright © 2002 American Society of Civil Engineers.
History
Received: Jul 30, 2001
Accepted: Dec 13, 2001
Published online: Jul 15, 2002
Published in print: Aug 2002
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