This example, described in detail by Valocchi et al. (1981) compared field observations from the Palo Alto Baylands groundwater recharge site to simulated data. At the Palo Alto site, an advanced wastewater treatment facility and an injection/extraction well field has been studied to determine whether direct injection of municipal effluents is a reliable and feasible strategy for producing potable water. Inorganic and chemical changes due to ion exchange processes have been observed at the site, and a mathematical simulation model of the transport of ion-exchanging solutes was developed and tested to understand and predict these chemical changes (Valocchi et al., 1981).
Figure 1 shows the field observations of the breakthrough of Ca2+ and Mg2+ at the Palo Alto site with MIN3P simulated data.
Valocchi A.J. et al., 1981. Transport of ion exchanging solutes in groundwater: Chromatographic theory and field simulation. Water Resour. Res, Vol. 17, No. 5. 1517-1527.