Biodegradation Modeling at Aviation Fuel Spill Site

Biodegradation has recently emerged as an effective process for contaminant attenuation in aquifers. In this paper the writers present the development of a two-dimensional model (BIOPLUME II) for contaminant transport influenced by oxygen-limited biodegradation. The model uses a dual-particle mover concept to simulate the transport of contaminants and oxygen in the subsurface. The reaction between oxygen and the contaminants is assumed to be instantaneous and is simulated using the principle of superposition. We also present preliminary results from a modeling effort using BIOPLUME II at an aviation gasoline spill where biodegradation is known to occur. The model was calibrated to field data collected before the installation of an interception pumping system at the site. The model was also used to simulate field conditions at the site over a two-year period with the pumping system in operation. Results indicate that the model predictions match the observed data and the observed rate of contaminant mass loss at the site reasonably well.