&EPA United States Environmental Protection Agency Research and Development (481) Solid Waste and Emergency Response (5102G) EPA/542/F-99/029 November 1999 Permeable Reactive Barriers Action Team BTDF Meumediaficm Technologies CurrentRTDF Action Teams Bioremediation Consortium Team !l ermeable Reactive Phytoremediation of Qrganics Action Team Sediments Remediatioii ; ? Action Team The Permeable Reactive Barriers Action Team was established in March 1995 as one of the seven Action Teams under the Remediation Technologies Development Forum (RTDF). The RTDF was created by the U.S. Environmental Protection Agency (EPA) in 1992 to foster collaboration between the public and private sec- tors in finding innovative solutions to mutual hazardous waste problems. The Action Team has met to discuss ongoing research, to identify development needs not currently being addressed, to identify and promote the funding of priority research needs to advance the acceptance of the technology, and to develop plans for collaborative field studies. The Permeable Reactive Barrier A permeable reactive barrier is a passive in situ treatment zone of reactive material that degrades or immobilizes contaminants as ground water flows through it. Permeable treatment walls are installed as permanent, semi-permanent, or replace- able units across the flow path of a contaminant plume. Natural gradients transport contaminants through strategically placed treatment media. The media degrade, sorb, precipitate, or remove chlorinated solvents, metals, radionuclides, and other pollutants. These barriers may contain reactants for degrading volatile organics, chelators for immobilizing metals, nutrients and oxygen for microorganisms to enhance bioremedi tion, or other agents. Degradation barriers facilitate reactions that break down contaminants in the plume into harmless byproducts. Precipitation barriers react with contaminants to form insoluble products that remain in the barrier as ground water continues to flow through. Sorption barriers adsorb or chelate contaminants. The Action Team's Mission The mission of the Permeable Reactive Barriers Action Team is to accelerate the development of cost-effective permeable barrier technologies. The Action Team undertakes development and evaluation efforts needed to achieve public and regu- latory acceptance of this technology. The efforts focus on: • Defining the hydraulics, geochemistry, and reactions that occur in the media and aquifers • Demonstrating and validating the technology's effectiveness • Developing protocols, guidance, and issue papers on design and effective implementation • Documenting effective emplacement techniques and configurations (engineering design and constructability) • Conducting an economic analysis of treatment cost Accomplishments Action Team members assisted with the design of the U.S. Air Force study, enti- tled "Catalytic In Situ Treatment of Chlorinated Solvents," and field work for the pilot-scale demonstration at the Area 5 site, Dover Air Force Base, Delaware. The Action Team also is actively involved in research and technology evaluation activ- ities at the U.S. Coast Guard (USCG) site near Elizabeth City, North Carolina. ------- The Action Team, in cooperation with EPA's Office of Research and Development, published "Permeable Reactive Barrier Technologies for Contaminant Remediation" in 1998. The document provides the most recent information on permeable reactive barrier (PRB) technologies. The document is available on the Team's home page on the RTDF World Wide Web site. Conceptual ConGguration of Permeable Barrier System RTDF Permeable Reactive Barrier Treated Ground Water Also in 1998, the Action Team prepared a status report on the use of permeable reactive barriers (PRBs) for ground-water remediation in the United States, Canada, and selected locations abroad. The report, available on the Team's home page on the RTDF Web site, includes profiles of about 30 ongoing and completed pilot- and full-scale PRB demonstrations and full-scale installations and a search- able bibliography of PRB-related articles and publications. The Action Team's Plans The Action Team, in partnership with the Interstate Technology Regulatory Cooperation (ITRC) Permeable Barriers Working Group, has developed a training course and manual to assist regulatory professionals in overseeing the design, implementation, and monitoring of ground-water remedies that involve the deployment of permeable reactive barriers (PRBs). The course will be offered in each EPA Region in 1999 and 2000. The Action Team's Steering Committee has launched a coordinated research effort focusing on the long-term performance of PRB's (i.e. how long will they work), the major issue restricting further acceptance and deployment of this tech- nology. The project will involve use of common techniques and monitoring approaches at selected PRB sites, collection and sharing of comparable data about PRB performance at each site over time, and development of peer-reviewed final reports on project milestones. Action Team Members The Action Team includes representatives from industry, government, and acade- mic organizations, such as the following: Industry DuPont Company EnviroMcial Technologies EnviroSources General Electric Ckornaiax In Situ Burners MtcMurcus Resources n Government U.S. Air Force U.S. Army Corps of Engineers U.S. Department of Energy U.S. Environmental Protection Agency U.S. Geological Survey Academia University of Waterloo Would You Like Moire Information? For more information on the Permeable Reactive Barriers Action Team, please contact the Team Co-chairs: Bob Puls, Ph.D. U.S. Environmental Protection Agency National Risk Management Research Laboratory P.O. 1198 Ada, OK 74820 Tel: 580-436-8543 Email: puls.robert@epa.gov John Vidumsky Superfund Program Manager DuPont Specialty Chemicals Jarley Mill Plaza 27/2226 : Lancaster Pike and Route 141 Tel: 3024$>2-1378 FB*- Bun* irtfarmatiofl oft &E HHB? or other, Action Teams, please visit the RTDF World Wide Web site 3<: ywByrtdf.org or contact: "US. Environmental Proteetidti .Agtncy 26 West Martin Luther King Drive Cincinnati, OH 05268 ' E-niailt olexsey.bob@epiimail.epa.gov * Walter Kovalick, Jr., Ph.D. U,S, Environmental Protection Agency 401 M Street, SW (51026) Washington, DC 24060 Tjsfc To request other RTDIf fact sheets, please write/call: ,,, , , EPA/NSCEP RO, Box 42419 , -' aaclana^ OH 45243 Phone; djipied on Recycled Paper ------- |