Fig. 6. Effect of increased dispersion relative to Br and pentafluorobenzoic acid (PFBA) breakthrough curves. Solute fluxes shown as a function of time after application. Blue and black lines represent Br and PFBA breakthrough patterns at irrigation rates of 4.4 and 0.89 mm h^–1, respectively. The orange line represents the best fit line using the one-dimensional convective–dispersive equation (CDE) on the lower irrigation rate (PFBA) while at the higher irrigation rate (Br) transport simulations were conducted by increasing the dispersion coefficient by 2 (gold line) and 10 times (pink line).