In this book a conceptual model of solute transport with bioremediation processes using sawdust as a matrix to improve the efficiency of bioremediation in the porous media was developed. The transport part of the model solves the advection-dispersion partial differential equations and the reaction part describes the heterotrophic metabolisms of several groups of bacteria. The model considers biological clogging effects, by calculating changes in porosity through converting biomass into volume, which directly reduces porosity of porous media. Unwanted substances rich in wastewater are usually...