Water Resources Research Act Program

Details for Project ID 2005MD78B

Theoretical and experimental evaluation of acetate thresholds as a monitoring tool for in situ bioremediation

Institute: Maryland
Year Established: 2005 Start Date: 2005-03-01 End Date: 2006-02-28
Total Federal Funds: $29,990 Total Non-Federal Funds: $60,068

Principal Investigators: Jennifer Becker, Hubert Montas, Eric Seagren

Project Summary: 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.