Use of Microcapsules in In Situ Permeable Barriers for pH Control of Groundwater
C. Marjorie Aelion, Ph.D.

We are examining the use of encapsulation of phosphate buffers to moderate pH changes caused by bacterial processes associated with contaminated environments. Some bacterial processes create acidic conditions, while other microbial processes increase pH.

The encapsulated buffers are coated with a pH sensitive polymer which dissolves when conditions go beyond the desired pH.   We have demonstrated in bioreactors and in sediment microcosms that pH rises due to bacterial denitrification, and that this rise can be controlled by adding encapsulated buffers.  These encapsulated buffers may be useful at field sites undergoing either biological or chemical remediation by controlling environmental conditions to maximize the efficiency of the remedial technology selected.

This project is funded by the Department of Energy.   Co-P.I. is Dr. Joe Flora from Department of Civil and Environmental Engineering.