Mobility in groundwaters

Herczeg A, Simpson J, Anderson R, Trier R, Mathieu G, Deck B (1988) Uranium and Radium mobility in groundwaters and brines within the Delaware basin. Southeastern New Mexico, USA Chem Geol 72 181-196... 

Free ions are surrounded only by water molecules and are very mobile in groundwater. Acid-base and dissolution reactions create free ions. 

Metal/ligand complexes (such as Al[OH]2+, Cu-humate) and organic/ligand complexes tend to be mobile in groundwater. 

Risk assessment of arsenic mobility in groundwaters in Langley, British Columbia using geochemical indicators... 

White AF, Dubrovsky NM (1994) Chemical oxidation-reduction controls on selenium mobility in groundwater systems. In Environmental Chemistry of Selenium. Frankenberger Jr. WT, Engberg RA (eds), Marcel Dekker, New York, p 185-221... 

Stille, P., Gauthier-Lafaye, F. et al. 2003. REE mobility in groundwater proximate to the natural fission reactor at Bangombe (Gabon). Chemical Geology, 198, 289-304. 

Szramek, K Walter, L.M. and McCall, P. (2004) Arsenic mobility in groundwater/surface water systems in carbonate-rich Pleistocene glacial drift aquifers (Michigan). Applied Geochemistry, 19(7), 1137-55. 

The removal of Ra by adsorption has been attributed to ion exchange reactions, electrostatic interactions with potential-determining ions at mineral surfaces, and surface- precipitation with BaSO 4. The adsorptive behavior of Ra2+ is similar to that of other divalent cationic metals in that it decreases with an increase in pH and is subject to competitive interactions with other ions in solution for adsorption sites. In the latter case, Ra is more mobile in groundwater that has a high total dissolved solids (TDS) content. It also appears that the adsorption of Ra + by soils and rocks may not be a completely reversible reaction (Benes et al. 1984, 1985 Landa and Reid 1982). 

Zhu, C., Sanders, S., and Rafal, M., 1993. Modeling coprecipitation reactions as the control of trace elements mobility in groundwater. Geol. Soc. Am. Abstr. with Programs, v. 25, no. 6, A-376. 

Welch A. H., Westjohn D. B., Helsel D. R., and Wanty R. B. (2000) Arsenic in ground water of the United States occurrence and geochemistry. Ground Water 38, 589-604. White A. and Dubrovsky N. (1994) Chemical oxidation-reduction controls on selenium mobility in groundwater systems. In Selenium in the Environment (eds. W. T. Frankenberger and S. Benson). Dekker, New York, chap. 8, pp. 185-221. 

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