Solute transport in groundwater is a process which has become of major importance during the last decades due to increasing contamination of ground water. This process usually occurs in a medium heterogeneous with respect to hydraulic conductivity and porosity, properties that affect the dispersion of the solutes.
The present paper describes an experimental investigation of the solute transport process in heterogeneous porous media, especially the connection between the statistical properties of their hydraulic conductivity distributions and the dispersion parameters governing the spreading of the solutes. The experimental results are compared to theoretical solutions derived for the same case of a solute pulse in an average uniform flow through a heterogeneous porous medium. Generally there is good agreement between the theory and the experiments.
In field applications this means that the dispersion parameters can be more readily determined from the soil properties. Furthermore, the deviations between dispersivities determined in laboratory columns and dispersitivies found under field conditions can be explained quantitatively by the differencies in the length scales and in the variances of the hydraulic conductivity distributions.