An application of geochemical modeling to environmental problems, illustrated with case studies of real-world environmental investigations.

An introduction to quantitative geochemical modeling for the researcher and advanced student.

This book provides a comprehensive overview of reaction processes in the Earth's crust and on its surface, both in the laboratory and in the field. A clear exposition of the underlying equations and calculation techniques is balanced by a large number of fully worked examples. The book uses The Geochemist's Workbench® modeling software, developed by the author and already installed at over 1000 universities and research facilities worldwide. Since publication of the first edition, the field of reaction modeling has continued to grow and find increasingly broad application. In particular, the description of microbial activity, surface chemistry, and redox chemistry within reaction models has become broader and more rigorous. These areas are covered in detail in this new edition, which was originally published in 2007. This text is written for graduate students and academic researchers in the fields of geochemistry, environmental engineering, contaminant hydrology, geomicrobiology, and numerical modeling.

The single most important factor for the successful application of a geochemical model is the knowledge and experience of the individual(s) conducting the modeling. Geochemical Modeling for Mine Site Characterization and Remediation is the fourth of six volumes in the Management Technologies for Metal Mining Influenced Water series about technologies for management of metal mine and metallurgical process drainage. This handbook describes the important components of hydrogeochemical modeling for mine environments, primarily those mines where sulfide minerals are present—metal mines and coal mines. It provides general guidelines on the strengths and limitations of geochemical modeling and an overview of its application to the hydrogeochemistry of both unmined mineralized sites and those contaminated from mineral extraction and mineral processing. The handbook includes an overview of the models behind the codes, explains vital geochemical computations, describes several modeling processes, provides a compilation of codes, and gives examples of their application, including both successes and failures. Hydrologic modeling is also included because mining contaminants most often migrate by surface water and groundwater transport, and contaminant concentrations are a function of water residence time as well as pathways. This is an indispensable resource for mine planners and engineers, environmental managers, land managers, consultants, researchers, government regulators, nongovernmental organizations, students, stakeholders, and anyone with an interest in mining influenced water. The other handbooks in the series are Basics of Metal Mining Influenced Water; Mitigation of Metal Mining Influenced Water; Mine Pit Lakes: Characteristics, Predictive Modeling, and Sustainability; Techniques for Predicting Metal Mining Influenced Water; and Sampling and Monitoring for the Mine Life Cycle.

An overview of the use of numerical methods to model reaction processes in the Earth's crust and on its surface. The theoretical foundations of the field are discussed, together with examples and case studies demonstrating the techniques that can be applied to scientific and practical problems.

To understand hydrochemistry and to analyze natural as well as man-made impacts on aquatic systems, hydrogeochemical models have been used since the 1960’s and more frequently in recent times. Numerical groundwater flow, transport, and geochemical models are important tools besides classical deterministic and analytical approaches. Solving complex linear or non-linear systems of equations, commonly with hundreds of unknown parameters, is a routine task for a PC. Modeling hydrogeochemical processes requires a detailed and accurate water analysis, as well as thermodynamic and kinetic data as input. Thermodynamic data, such as complex formation constants and solubility-products, are often provided as databases within the respective programs. However, the description of surface-controlled reactions (sorption, cation exchange, surface complexation) and kinetically controlled reactions requires additional input data. Unlike groundwater flow and transport models, thermodynamic models, in principal, do not need any calibration. However, considering surface-controlled or kinetically controlled reaction models might be subject to calibration. Typical problems for the application of geochemical models are: • speciation • determination of saturation indices • adjustment of equilibria/disequilibria for minerals or gases • mixing of different waters • modeling the effects of temperature • stoichiometric reactions (e.g. titration) • reactions with solids, fluids, and gaseous phases (in open and closed systems) • sorption (cation exchange, surface complexation) • inverse modeling • kinetically controlled reactions • reactive transport Hydrogeochemical models depend on the quality of the chemical analysis, the boundary conditions presumed by the program, theoretical concepts (e.g.

This well-organised, comprehensive reference and textbook describes rate models developed from fundamental kinetic theory and presents models using consistent terminology and notation. Major topics include rate equations, reactor theory, transition state theory, surface reactivity, advective and diffusive transport, aggregation kinetics, nucleation kinetics and solid-solid transformation rates. The theoretical basis and mathematical derivation of each model is presented in detail and illustrated with worked examples from real-world applications to geochemical problems. The book is also supported by online resources: self-study problems put students' new learning into practice, and spreadsheets provide the full data used in figures and examples, enabling students to manipulate the data for themselves. This is an ideal overview for graduate students, providing a solid understanding of geochemical kinetics. It will also provide researchers and professional geochemists with a valuable reference for solving scientific and engineering problems.