WATER RESOURCES RESEARCH GRANT PROPOSAL
WATER RESOURCES RESEARCH GRANT PROPOSAL
Project ID: 2005MD78B
Title: Theoretical and experimental evaluation of acetate thresholds as a monitoring tool for in situ bioremediation
Project Type: Research
Focus Categories: Toxic Substances, Groundwater, Methods
Keywords: groundwater, in situ bioremediation, petroleum hydrocarbons, monitoring, redox indicator
Start Date: 03/01/2005
End Date: 02/28/2006
Federal Funds: $29,990
Non-Federal Matching Funds: $60,068
Congressional District: 5th District of Maryland
Principal Investigators:
Jennifer G. Becker
Hubert J. Montas
University of Maryland
Eric A. Seagren
University of Maryland
Abstract
In situ bioremediation approaches offer great potential for cost-effective clean-up of environmental contamination. However, demonstrating the success of in situ bioremediation can be challenging due to the heterogeneous, dynamic, and inaccessible nature of the subsurface. The consumption of electron acceptors during bioremediation of hydrocarbons and other contaminants can result in shifts in the predominant terminal electron-accepting processes (TEAPs), which may be useful for monitoring. Because traditional assessment tools have disadvantages, an accurate indicator of TEAPs is still needed. Using an integrated experimental and modeling approach, this study will systematically test the hypothesis that characteristic ranges of acetate thresholds may exist for different TEAPs and, therefore, acetate concentrations may be useful for monitoring bioremediation. Acetate thresholds established by pure microbial cultures that utilize acetate as an electron donor and different TEAPs will be measured experimentally using batch laboratory systems. The importance of kinetic and thermodynamic factors in controlling acetate thresholds will be evaluated using a mechanistic mathematical model. Model parameters will be obtained by fitting the model to the experimental data. The usefulness of acetate thresholds as indicators of bioremediation will be evaluated by measuring acetate concentrations in contaminated sediments and comparing measured values to model-predicted concentrations.