ANALYSIS OF BIODEGRADATION AND BACTERIAL TRANSPORT - COMPARISON OF MODELS WITH KINETIC AND EQUILIBRIUM BACTERIAL ADSORPTION

An advection/dispersion/sorption model incorporating Monod kinetics (m odified to describe bacterial growth near threshold concentrations of the contaminant) was used to analyze breakthrough curve and concentrat ion profile data from soil column experiments previously reported for degradation of 1,2-dichlorobenzene by Pseudomonas P51. Two models for bacterial sorption in the column were compared: one assumed an equilib rium process and the other used first-order kinetics for adsorption an d desorption. Numerical solutions of both models using reasonable para meter values represented the column concentration profile data well. T he two adsorption models yielded qualitatively and quantitatively simi lar results for contaminant concentration data. However, significant d ifferences in bacteria distributions and breakthrough curves were pred icted from the two adsorption models. These are important consideratio ns for distinguishing between various models of bacterial migration fo r field-scale applications.