A NOVEL PERMEABLE BARRIER FOR GROUNDWATER BIOREMEDIATION

Description (provided by applicant): This Small Business Innovative Research Phase I project proposes the use of a novel, highly effective biotechnology approach in the area of environmental bioremediation for chemical contaminant mixtures. The investigators propose to overcome some of the disadvantages of in situ bioremediation techniques, such as bioaugmentation or biostimulation, by using an innovative and cost-effective technology called Biological Permeable Barrier (BPB) (U.S. patent). BPB technology uses acclimated microorganisms, encapsulated with an unique polymeric matrix, to degrade contaminants. For this research, the investigators propose to demonstrate BPB technology to biodegrade TCE, perchlorate, and a mixture of the two to non-toxic end products under field operating conditions. Following appropriate treatability studies in the laboratory (batch and column studies) a field pilot study will be designed to and installed in the groundwater contaminated zone at the Longhorn Army Ammunition Plant, Karnack, TX to demonstrate its effectiveness to biodegrade TCE and perchlorate contaminants. The encapsulated cells embedded in situ BPB reactor cells are shielded from harsh surroundings while target pollutants flow through the matrix to be metabolized. BPB offers many advantages over traditional in situ bioremediation technologies, including: (1) protection of viable cells from shock contaminant loads and environmental stresses, (2) increased bacterial mass per unit volume, (3) the ability to cotreat several contaminants at the same time, (4) it can be designed as a passive treatment with reduced operation and management, and (5) it minimizes adverse health effects to workers and the public by eliminating contact exposure. Current trends and near-term priorities for selection of treatment alternatives are toward in situ remediation of large sites and this research responds to this trend. The BPB concept represents a "step-change" in available technologies from both a lower cost and remediation effectiveness perspective. This research will provide an opportunity to demonstrate the effectiveness of this already laboratory-proven technology in the field.