Computer programs GEOCHEM

Chemical Modeling of Trace Metal Equilibria in Contaminated Soil Solutions Using the Computer Program GEOCHEM... 

Mattigod, S. V. and Sposito, G. Chemical modeling of trace metal equilibria in contaminated soil solutions using the computer program GEOCHEM, j[n Jenne, E.A., ed., "Chemical Modeling in Aqueous Systems. Speciation, Sorption, Solubiliiy, and Kinetics." Amer. Chem. Soc., 1978 (This volume). 

Parkhurst DL, Appelo CAJ (1999) User s guide to PHREEQC (version 2) - a computer program for speciation, batchreaction, one-dimensional transport, and inverse geochemical calculations U.S. Geological Survey Water-Resources Investigations Report 99-4259, 312 pp... 

Garrels and Thompson s calculation, computed by hand, is the basis for a class of geochemical models that predict species distributions, mineral saturation states, and gas fugacities from chemical analyses. This class of models stems from the distinction between a chemical analysis, which reflects a solution s bulk composition, and the actual distribution of species in a solution. Such equilibrium models have become widely applied, thanks in part to the dissemination of reliable computer programs such as SOLMNEQ (Kharaka and Barnes, 1973) and WATEQ (Truesdell and Jones, 1974). 

Kharaka, Y. K., W. D. Gunter, P. K. Aggarwal, E. H. Perkins and J. D. DeBraal, 1988, Solmineq.88, a computer program for geochemical modeling of water-rock interactions. US Geological Survey Water Resources Investigation Report 88—4227. 

Parkhurst, D. L., D. C. Thorstenson and L. N. Plummer, 1980, Phreeqe - a computer program for geochemical calculations. US Geological Survey Water-Resources Investigations Report 80-96. 

Plummer, L. N., D.L. Parkhurst, G. W. Fleming and S. A. Dunkle, 1988, PHRQPITZ, a computer program incorporating Pitzer s equations for calculation of geochemical reactions in brines. US Geological Survey Water-Resources Investigations Report 88—4153. 

Wolery, T. J., 1983, Eq3nr, a computer program for geochemical aqueous speciat-ion-solubility calculations user s guide and documentation. Lawrence Livermore National Laboratory Report UCRL-53414. 

Parkhurst, D.L. Appelo, C.A.J. 1999. User s Guide to PHREEQC (Version 2.15.0)-A Computer Program for Speciation, Batch-Reaction, One-Dimensional Transport and Inverse Geochemical Calculations. U.S. Geological Survey, Water Resources Investigation Report 99-4259. 

Charlton, S.R. Parkhurst, D.L 2002. PHREEQCI-A computer program for speciation,reaction-path, advective transport, and inverse geochemical reactions. U.S. Geological Surveys Water-Resources Investigations, 95-4227. 

Wolery T. I (1983). EQ3NR. A Computer Program for Geochemical Aqueous Speciation-Solubility Calculations User s Guide and Documentation Lawrence Livermore Laboratory, Livermore, Cal., UCRL-53414. 

PARKHURST, D. L. 1995. Users Guide to PHREEQC -A Computer Program for Speciation, Reaction-Path, Advective-Transport, and Inverse Geochemical Calculations. US Geological Survey Water Resources Investigations Report 95-4227, Reston. VA. 

Additional information on adsorption mechanisms and models is in Stollenwerk (2003), 93-99 and Prasad (1994). Foster (2003) also discusses in considerable detail how As(III) and As(V) may adsorb and coordinate on the surfaces of various iron, aluminum, and manganese (oxy)(hydr)oxides. In adsorption studies, relevant laboratory parameters include arsenic and adsorbent concentrations, adsorbent chemistry and surface area, surface site densities, and the equilibrium constants of the relevant reactions (Stollenwerk, 2003), 95. Once laboratory data are available, MINTEQA2 (Allison, Brown and Novo-Gradac, 1991), PHREEQC (Parkhurst and Appelo, 1999), and other geochemical computer programs may be used to derive the adsorption models. 

Mitzman, S. (1999) The application of PHREEQCi, a geochemical computer program, to aid in the management of a wastewater treatment wetland. Master s Thesis, Texas A M University, College Station, p. 163. 

Felmy, A. R. Girvin, D. C. and Jenne, E. A. "MINTEQ - A Computer Program for Calculating Aqueous Geochemical Equilibria" Battelle, Pacific Northwest Laboratories Richland, Washington (in preparation). 

Mattigod, S.V and Sposito, G. (1979) GEOCHEM A Computer Program for the Calculation of Chemical Equilibria in Soil Solutions and Other Water Systems. Department of Soils and Environmental Sciences, University of California, Riverside, CA. 

Parkhurst, D.L., Thorstenson, D.C. and Plummer, N.L. (1980) PHREEQE -A Computer Program for Geochemical Calculations. US Geological Survey Water Research Investigation Report 80-96. 

Parkhurst DL, Thorstenson D, Plummer L. 1990. PHREEQE a computer program for geochemical calculations. No. USGS/WRI-80-96. Reston (VA) US Geological Survey, 195 p. http //water.usgs.gov/software/phreeqe.html (accessed December 28, 2007). 

Stanley, C. R. (1987). Probplot. An interactive computer program to fit mixtures of normal (or lognormal) distributions with maximum likelihood of optimization procedures. Assoc. Explor. Geochem. Spec. Vol. 14, 39. 

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