Transport and fate of metals

Fate and transport of metals from an abandoned tailings impoundment after 70 years of sulfide oxidation. In Proc. Sudbury 03, Mining and the Environment III. Sudbury, Ontario, pp. 238—247. 

Cu, have shown toxic effects on a diverse assortment of aquatic biota (6 8). The very same metal ions, on the other hand, portray a reduction or complete eradication of toxic effects when complexed with natural organic matter. Fate and transport of metal ions in the environment are also governed by associations with fulvic acid material. Therefore, determination of stability constants between FA ligand sites and potentially hazardous metal ions should be considered fundamentally important. 

Dynamic reactions in the subsurface environment are critical in affecting the fate and transport of metals, as well as a number of other important processes (Figure 1). Soils and sediments have a remarkable ability to sorb metals. 

Ecologically, copper is a trace element essential to many plants and animals. However, high levels of copper in soil can be directly toxic to certain soil microorganisms and can disrupt important microbial processes in soil, such as nitrogen and phosphorus cycling. Copper is typically found in the environment as a solid metal in soils and soil sediment in surface water. There is no evidence that biotransformation processes have a significant bearing on the fate and transport of copper in water. 

Lawson, N.M., R.P. Mason, and J.-M. Laporte. 2001. The fate and transport of mercury, methylmercury, and other trace metals in Chesapeake Bay tributaries. Water Res. 35 501-515. 

Therefore, the role of physicochemical-biological interfacial interactions in controlling the transformation, transport, fate, and toxicity of metals and metalloids in soil and surrounding environments, especially the rhizosphere, which is the bottleneck of contamination of the terrestrial food chain, deserves increasing attention. In this chapter we present an overview of this emerging and extremely important area of science, to advance our knowledge of the interface between physicochemical and biological reactions and processes in the environment. 

Brady et al. (2003) proposed that a site-specific screening approach followed by sequential extraction measurements could be an appropriate method to determine if a contaminated site is suited for MNA. In the first step, the site s chemical and hydrological conditions are assessed from standard site characterization data. The MNAtoolbox (www.sandia.gov/eesector/gs/gc/na/mnahome.html) provides a rapid initial assessment of the chemical and hydrologic conditions for MNA. The site-specific assessment for natural attenuation is then evaluated using sequential extraction experiments that enhance the site s characterization, determine the hioavailability, fate, and transport of the metal(loid)(s) in question, and assess natural attenuation against other remediation options (such as phytoremediation). 

Strawn, D.G., and D.L. Sparks. 1999. Sorption kinetics of trace metals in soils and soil materials, p. 1-28. In H.M. Selim and I.K. Iskandar (ed.) Fate and transport of heavy metals in the vadose zone. CRC/Lewis Publ., Boca Raton, FL. 

The NA pathways of inorganics and data necessary to characterize the process are summarized in Table 10.3. However, the processes that affect speciation, fate, and transport of arsenic and metals are not sufficiently understood. According to US EPA (2001), there is need to ... 

James RO, Healy TW (1972) The adsorption of hydrolyzable metal ions at the oxide-water interface. III. A thermodynamic model of adsorption. J Colloid Interface Sci 40 65-81 Jardine PM, Fendorf SE, Mayes MA, Larsen IL, Brooks SC, Bailey WB (1999) Fate and transport of hexavalent chromium in undisturbed heterogeneous soil. Environ Sci Technol 33 2939-2944 Jayanetti S, Mayanovic RA, Anderson AJ, Bassett WA, Chou I-M (2001) Analysis of radiation-induced small Cu particle cluster formation in aqueous CuCl2. J Chem Phys 115 954-962. 

Gobran, G.R., Clegg, S., Courchesne, F., 1999. The rhizosphere and trace element acquisition. In Selim, H.M., Iskander, A. (Eds.), Fate and Transport of Heavy Metals in the Vadouse Zone, CRC Press, Boca Raton, FL, pp. 225-250. 

Fares M. Howari (water and soil management environmental quality fate and transport of contaminants natural resources assessment and development heavy metals uranium geology salinity geochemistry hydrology remote sensing). Department of Natural Science and Public Health, Zayed University (ZU), Abu Dhabi... 

Caruso BS, Cox LTJ, Runkel RE, Velleux ML, Bencala KE, Nordstrom DK, Julien PY, Butler BA, Alpers CN, Marion A, Smith KS (2008) Metals fate and transport modelling in streams and watersheds state of the science and SEPA workshop review. Hydrol Process 22 4011... 

The chemical industry has historically been the top TRl emitter, but by figuring in toxicity and exposure, the baton has been passed to a new leader—the primary metals industrial sector. The model does not provide chemical-specific quantitative risk assessments. Instead, EPA developed toxicity weights for each chemical. Those are combined with exposure, fate, and transport information to generate an indicator value for the health impact of emissions from a particular factory (Johnson, 1999). 

The facilitated transport of compounds by colloids, illustrated schematically in Figure 1.1, is important in several areas and especially in the study of the fate and transport processes of hydrophobic organic compounds and metal ions in the environment. This facilitated transport also has implications in other areas in which colloid diffusion through porous... 

Interest in trace element speciation studies in natural waters has increased considerably during the last decade. It has become apparent that data on total concentrations of any element rather than on individual well defined chemical entities, are often inadequate to identify transport mechanisms, ultimate fate and toxicity of particular elements to organisms. A study of the different trace metal species and their relative distribution will assist in understanding the chemical processes that take place in the highly reactive estuarine zone and in the open sea. These processes include the rate at which chemical processes take place, the participation in geochemical processes (precipitation/dissolution, adsorption/desorption). 

An understanding of the weathering and transport processes controlling the fate and flux of trace metals in pristine environments is important in evaluating the capacity of receiving waters to accommodate wastes without detrimental effects. The Amazon River system, which is relatively free of industrial and agricultural interference. 

US Environmental Protection Agency (US EPA) (2005). RituaUstic use of mercury simulation A preliminary investigation of metallic mercury vapor fate and transport in a trailer. Office of Solid Waste and Emergency Response. Washington, DC, EPA/540/-04/006. 

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