Geological media

Plutonium uptake on geologic media under various conditions have been studied extensively during the last few years, and reviewed (e.g. in ref. 60). It should be emphasized that data from various experiments are rarely directly comparable, due to differences in experimental techniques, chemical conditions and other parameters of importance. A detailed discussion of sorption data is outside the scope of this paper. 

Photophysics, Pu hexafluoride gas. 155-60 Physical adsorption, geologic media 286-92 Physical constants, Pu(III and IV)... 

Biofilms adhere to surfaces, hence in nearly all systems of interest, whether a medical device or geological media, transport of mass from bulk fluid to the biofilm-fluid interface is impacted by the velocity field [24, 25]. Coupling of the velocity field to mass transport is a fundamental aspect of mass conservation [2]. The concentration of a species c(r,t) satisfies the advection diffusion equation... 

Bachu S. Sequestration of C02 in geological media criteria and approach for site selection in response to climate change. 2000 Energy Conversion and Management 41 953-970. 

Bachu S., Bonijoly D., et al. Screening and ranking of sedimentary basins for sequestration of C02 in geological media in response to climate change. 2003 Environmental Geology 44 277-289. 

Neuman, S. P., 1990, Universal scaling of hydraulic conductivities and dispersivi-ties in geologic media. Water Resources Research 26,1749-1758... 

Xu, T., E.L. Sonnenthal, N. Spycher and K. Pruess, 2004, TOUGHREACT user s guide A simulation program for non-isothermal multiphase reactive geochemical transport in variably saturated geologic media. Report LBNL-55460, Lawrence Berkeley National Laboratory, Berkeley, California. 

Elemental abundances in various types of geological media such as rocks, sediments and soils of China have been studied since 1980s. These data were published in many literatures (Chi Yan 2007 Yan Chi 1997, 2005 Ren et al. 1998 Zhao Yan 1994 Zhu et al. 2006). To provide readers with a general overview and convenient use, the authors collected these published data and compiled a concise data set in this paper. 

The data listed in Table 1 factually reflect abundances of chemical elements in various kinds of geological media of rocks, soils, sediments and in the continental crust of China, because the samples have a good representativity for various media and elements analyzed by high-quality analytical methods under strict quality... 

Parker, B. L., Gillham, R. W., and Cherry, J. A., 1994, Diffusive Disappearance of Immiscible-Phase Organic Liquids in Fractured Geologic Media Ground Water, Vol. 32, No. 5, September/October, pp. 805-820. 

Release rate data from actual radioactive waste forms is needed to evaluate the safety of emplacing nuclear wastes in geologic media. However, in addition to waste form development studies, such as the leach test just described, a comprehensive program was started to obtain release data from candidate waste forms for geologic disposal. 

In previous work (l.> > ) it was found that the kinetics of sorption was an important parameter affecting the migration of nuclides in geologic media. For example, in experiments designed to measure the kinetics of reaction for radionuclides in solution with tablets of rock, it was found that periods from several minutes to several hours were required for the radionuclides to reach steady state concentrations on the rock tablets and in the solutions. Figure 1 shows the reaction curves found for the sorption of plutonium and americium from solution by a tablet of granite. The reaction rates for the sorption of plutonium and americium from solution are not the same, and both require a number of hours to reach steady state concentrations. 

This paper describes an experimental study of the applicability of the ARDISC model to laboratory studies of nuclide migration in geologic media. 

The results of the experiments presented in this paper demonstrate that the migration of nuclides in geologic media can be studied experimentally and treated in at least a semiquantitative fashion using kinetic and partitioning data. The ARDISC model is a useful aid in analyzing nuclide migration data obtained in laboratory experiments. But the ARDISC model is limited to first-order sorption kinetics. 

Phenomena such as nuclide transport by particles or nuclide transport in colloidal form will interfere with a kinetic approach to predicting nuclide migration. The results indicate that the measurement of kinetic parameters may be as important to understanding the migration of a nuclide through a geologic media as the measurement of the equilibrium-sorption value (Kj). 

Rickert, P. G., Seitz, M. G., Fried, S. M., Friedman, A. M., and Steindler, M. J., "Transport Properties of Nuclear Waste in Geologic Media," report to the Waste Isolation Safety Assessment Program, March, ANL program code 85249-00 (1978). 

Studies of Nuclear-Waste Migration in Geologic Media," p. 34, M. G. Seitz, P. G. Rickert, S. M. Fried, A. M. Friedman, and M. J. Steindler, Argonne National Laboratory Report ANL-78-8, 1978. 

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