American Research in the Geochemical Modeling of Groundwater

The advent of digital computers has allowed the development of sophisticated geochemical models for describing and predicting the chemical behavior of complex natural waters. More than 50 such models have been developed and published in the North American literature. Much of the impetus for the development of geochemical computer models comes from the need to protect the chemical quality of groundwater, and from a search for safe methods of geologic disposal of nuclear wastes.

The geochemical computer codes can be broken down into three main categories, in order of increasing complexity: (1) equilibrium codes, (2) mass-transfer codes, and (3) mass-transport codes.

Much research still remains to be done in this area. Additional effort must be devoted to the complication and critical evaluation of the thermodynamic data which form the basis of all geochemical models, as well as to the determination of the kinetics of heterogeneous and homogeneous relations. A critical need exists for the investigation of the behavior of natural and synthetic organics in aqueous systems. Fundamental research must also continue on improving the mathematical and computational aspects of the increasingly complex models.