Evaluation of Fuel Oxygenate Degradation in the Vadose Zone

Groundwater contamination by petroleum products poses a potential human health and safety risk. Methyl tert-butyl ether (MTBE) was a commonly used fuel oxygenate that was added to gasoline to meet environmental regulations. The widespread use of MTBE resulted in significant contamination of drinking water supplies across the United States. This research evaluated the degradation characteristics of potential alternative fuel oxygenates in the vadose zone. One fuel oxygenate being considered as an alternative to MTBE is diisopropyl ether (DIPE). Specifically, this thesis sought to answer three research questions: what is the potential for DIPE degradation in soil without prior microbial augmentation, how does the presence of co-contaminants, such as ethanol and toluene, impact the biodegradation of DIPE, and will the increased use of DIPE represent a potential environmental risk? Previous research related to fuel oxygenates has focused primarily on oxygenates currently used, such as MTBE and ethanol. This research focused on a potential alternative to MTBE prior to its widespread implementation and use.