FIG. 3. Conceptual chemical nonequilibrium models for reactive solute transport. In the plots, is the water content, _mo and _im in (d) are water contents of the mobile and immobile flow regions, respectively; _M and _F in (e) are water contents of the matrix and macropore (fracture) regions, respectively; c are concentrations of the corresponding regions, s^e are sorbed concentrations in equilibrium with the liquid concentrations of the corresponding regions, and s^k are kinetically sorbed solute concentrations of the corresponding regions.