FIG. 7. (A) Measured and fitted breakthrough curves and (B) retention profiles for Rhodococcus rhodochrous at 80% saturation. Fitted curves were obtained using the attachment model, the Langmuirian model, and the 2 site model. In Fig. 7A, 152 min is equal to 1 pore volume. C/C₀ = relative effluent concentration, where C₀ is the influent concentration of bacteria; N_t, number of bacteria recovered in the sand; N_i, number in a unit volume of the input bacterial suspension.