Permeable Reactive Barriers, Permeable Treatment Zones, and Application of Zero-Valent Iron◊ Bioreactor Landfills
◊ Bioremediation of Chlorinated Solvents
◊ Bioventing and Biosparging
◊ Electrokinetics: Electric Current Technologies
◊ Fracturing
◊ Ground-Water Circulating Wells
◊ In Situ Flushing
◊ In Situ Oxidation
◊ Multi-Phase Extraction
◊ Natural Attenuation
◊ Permeable Reactive Barriers
◊ Phytoremediation
◊ Remediation Optimization
◊ Soil Vapor Extraction
◊ Soil Washing
◊ Solvent Extraction
◊ Thermal Treatment: Ex Situ
◊ Thermal Treatment: In Situ
|
|
Overview
A permeable reactive barrier (PRB) is defined as an in situ method for remediating contaminated ground water that combines a passive chemical or biological treatment zone with subsurface fluid flow management. Treatment media may include zero-valent iron, chelators, sorbents, and microbes to address a wide variety of ground-water contaminants, such as chlorinated solvents, other organics, metals, inorganics, and radionuclides. The contaminants are concentrated and either degraded or retained in the barrier material, which may need to be replaced periodically. There are approximately 100 PRBs operating in the United States and at least 25 internationally.
PRBs can be installed as permanent or semi-permanent units. The most commonly used PRB configuration is that of a continuous trench in which the treatment material is backfilled. The trench is perpendicular to and intersects the ground-water plume. Another frequently used configuration is the funnel and gate, in which low-permeability walls (the funnel) direct the ground-water plume toward a permeable treatment zone (the gate). Some gates are in situ reactors that are readily accessible to facilitate the removal and replacement of reactive media. These PRBs use collection trenches, funnels, or complete containment to capture the plume and pass the ground water, by gravity or hydraulic head, through a vessel containing either a single treatment medium or sequential media. In circumstances where in situ treatment is found to be impracticable, reactive vessels have been located above ground.
Zero-valent iron has performed so successfully in PRB technology that it is now being applied directly for source zone treatment. Though this measure is not considered a PRB, examples of the technology will be included in the PRB pages because the reactive media and treatment mechanism are related. Pneumatic fracturing and injection, hydraulic fracturing, and injection via direct push rigs have been used successfully to introduce the reactive media to the ground-water or soil source area.
4.40 Passive/Reactive Treatment Walls
Remediation Technologies Screening Matrix and Reference Guide, Version 4.0. Federal Remediation Technologies Roundtable.
Advances in Permeable Reactive Barrier Technologies. Technical Data Sheet
2002. Naval Facilities Engineering Service Center, Port Hueneme, CA. NFESC-TDS-2089-ENV, DTIC: ADA410697, 5 pp.
A Citizen's Guide to Permeable Reactive Barriers (PRBs)
EPA 542-F-01-005, 2001
The Citizen's Guide Series are 2-page fact sheets that provide a general description on approaches to clean up contaminated was sites. The fact sheets cover five questions about each clean up approach: What is it?, How does it work?, Is it safe?, How long will it take?, and Why use it?.
Guía del Ciudadano para las Barreras Reactivas
EPA 542-F-01-005S, 2001
La Serie de Guías del Ciudadano son boletines de dos páginas con datos que proveen una descripción general en cómo sanear sitios contaminados. Estos boletines con datos que cubren cinco preguntas acerca de cada procedimiento de saneamiento: ¿Qúe es?, ¿Cómo trabaja?, ¿Es seguro?, ¿Cúanto tiempo requerirá?, y ¿Por qué debe de usarse?
Permeable Reactive Barrier Technologies for Contaminant Remediation
EPA 600-R-98-125, 1998
The goal of this Issue Paper is to provide the most recent information available on PRB technologies and to do so in a format that is useful to stakeholders such as implementors, state and federal regulators, Native American tribes, consultants, contractors, and all other interested parties.
Permeable Reactive Subsurface Barriers for the Interception and Remediation of Chlorinated Hydrocarbon and Chromium (VI) Plumes in Ground Water
EPA 600-F-97-008, 1997
Prepared by EPA's ORD, the document discusses the use of barrier walls employing zero-valent iron as the reactive substrate for treating groundwater contaminated with chlorinated hydrocarbons or chromium.
Treatment Technologies for Site Cleanup: Annual Status Report (ASR), Twelfth Edition
EPA 542-R-07-012, 2007
The Twelfth Edition of this report, published by the EPA Office of Superfund Remediation and Technology Innovation (OSRTI) in September 2007, documents treatment technology applications at more than 1,900 soil and groundwater cleanup projects at National Priorities List (NPL) sites. The status of more than 1,200 projects included in the ASR Eleventh Edition is updated, and information about 192 new projects derived from Records of Decision (ROD) signed from 2002 through 2005 is added. The report also includes a special section about on-site containment remedies. The ASR is based on the analysis of nearly 3,000 RODs signed since 1982 at 1,536 NPL sites. The online version includes new downloadable spreadsheets with the data for several of the key tables and figures in the report. Specific information about each technology application included in the ASR Twelfth Edition is available in the ASR Remediation Database.
Disclaimer
http://clu-in.org/techfocus/default.focus/sec/Permeable%5F
Last updated on Thursday, December 18, 2008