Contaminant transport and biodegradation: 2. Conceptual model and test simulations

A conceptual model of subsurface contaminant transport with biodegradation is presented. This model incorporates both aerobic and anaerobic reactions, with several models of differing complexity presented for the anaerobic case. Nutrient uptake is described using Michaelis‐Menten expressions, which are incorporated into a multiple nutrient uptake model. Several uptake inhibition factors are also included in the model. The mathematical model that results takes the form of a series of reactive transport equations. These equations are coupled nonlinearly through the reaction terms, which are themselves coupled to growth equations for subsurface bacterial populations. Example simulations are presented for a variety of cases, ranging from one‐substrate, one‐population aerobic degradation to multisubstrate, multipopulation anaerobic consortium degradation.