Wetlands remediation

Wetland remediation involves a combination of interactions including microbial adsorption of metals, metal bioaccumulation, bacterial oxidation of metals, and sulfate reduction (Fennessy Mitsch, 1989 Kleinmann Hedin, 1989). Sulfate reduction produces sulfides which in turn precipitate metals and reduce aqueous metal concentrations. The high organic matter content in wetland sediments provides the ideal environment for sulfate-reducing populations and for the precipitation of metal complexes. Some metal precipitation may also occur in response to the formation of carbonate minerals (Kleinmann Hedin, 1989). In addition to the aforementioned microbial activities, plants, including cattails, grasses, and mosses, serve as biofilters for metals (Brierley, Brierley Davidson, 1989). 

Figure 23.2.4. Microbial communities have the remarkable ability to adapt to utilize a number of carbon sources. Montgomery et al. suggest that the proportion of PAH degraders (shown as pie fraction) in a population can be reflected by their overall activity (measured by protein production) and their ability to mineralize the contaminant to COj. [Figure adapted from Montgomery, M. T., T. J. Boyd, J. K. Steele, D. M. Ward, D. C. Smith, B. J. Spargo, R. B. Coffin, J. W. Pohlman, M. Slenska, and J. G. Mueller, International Conference on Wetlands Remediation, Salt Lake City, UT, November 16-17, 1999.]...

Natural Wastewater Treatment Systems. Waste-water and storm-water effluents can be treated and reused in natural systems of plants, algae, and other living organisms. Sequenced constructed ecosystems mimic natural processes of land and water habitats. Applications include greenhouses, rain gardens, aquatic systems, and wetlands remediation. 

Wetlands Remediation. For some localities, wetlands are an essential component of wastewater... 

Sources of tliis information include site descriptions mid data from the preliminary assessment (PA), site inspection (SI), and remedial investigation (RI) reports. Other sources include local soil sur eys, wetland maps, aerial photographs, and reports by the National Oceanograpliic and Atmospheric Association (NOAA) and tlie U.S. Geological Sur ey (USGS). One cmi also consult with appropriate tecluiical e.xperts (e.g., hydrogeologists, air modelers) as needed to cluuacterize tlie site. 

Runes, H.B. and J.J. Jenkins. 1999. Atrazine remediation in a wetland mesocosm. Book of Abstracts, Part 1, AGRO 128. 218th American Chemical Society National Meeting, New Orleans, LA, August 22-26, 1999. 

Keywords Military sites, explosives, TNT, in situ remediation, water treatment, eonstrueted wetlands... 

Otte, M. L. (1991). Contamination of coastal wetlands with heavy metals factors affecting uptake of heavy metals by salt marsh plants. In Ecological Responses to Environmental Stresses, ed. J. Rozema J. A. C. Verkleij, pp. 126-33. London Kluwer Academic. Peters, R. W. Shem, L. (1992). Use of chelating agents for remediation of heavy metal contaminated soil. In Environmental Remediation, ed. American Chemical Society, pp. 70-84. Washington, D.C. American Chemical Society. 

Figure 14 Schematic diagram of a mine-waste impoundment with a combined remediation approach, including a cover to prevent O2 and water ingress, in situ mixing to geochemically stabilize waste, permeable reactive barrier in aquifer to treat subsurface drainage, and wetland for surface treatment of drainage.

SRB remove sulfate and metals from solutions. Consequently, there has been considerable interest in stimulating SRB in order to remediate environments contaminated by AMD (e.g., constructed wetlands Berezowsky 1995 Thompson et al. 2000 Kolmert and Johnson 2001). However, the nanoparticulate nature of products means they are potentially fairly mobile and prone to rapid re-oxidation. 

Berezowsky M (1995) Constructed wetlands for remediation of urban waste waters. Geosci Canada 22 129-141... 

Scientists are now exploring the use of plants and their associated microorganisms for remediation, which is called phytoremediation. This is a low cost process that is proving effective for a wide variety of contaminants, including petroleum hydrocarbons. It can be used in combination with other remediation technologies and may prove useful in the future for treating oiled soils or wetlands. It takes several years to remediate a site and cleanup is limited to the depth of the soil within reach of the plant s roots. 

Siegel LS, Alshawabkeh AN and Hamilton MA (2002) Modeling cesium partitioning in the rhizo-sphere In Wetlands and Remediation. Battelle Press, Columbus, pp. 73-81. 

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