A permeable reactive barrier (PRB) is a continuous, in situ permeable treatment zone designed to intercept and remediate a contaminant plume. PRBs are often intended as a source-term management remedy or as an on-site containment remedy. Over the past 10 years, the use of iron-based PRBs has evolved from innovative to accepted standard practice for the containment and treatment of a variety of groundwater contaminants. Reactive media such as carbon sources (compost), limestone, granular activated carbon, zeolites, and others had also been deployed in recent years to treat metals and some organic compounds. Research and deployment of bio-barrier systems is also growing in recent years, particularly for treatment of chlorinated solvents and petroleum hydrocarbon constituents.
This training presents updated information regarding new developments, innovative approaches, and lessons learned in the application of PRBs to treat a variety of groundwater contaminants. The information will be presented by reviewing the approaches and results at several sites where PRBs have been deployed. The training is based on the ITRC guidance document titled Permeable Reactive Barriers: Lessons Learned / New Directions (PRB-4, 2005). Case studies from around the country are included in the training to show various designs, contaminants, reactive media, and cost data for PRB systems. The training provides new information on iron-based PRB systems while providing a solid introduction to the non-iron PRBs. As a prerequisite to this course, we ask that you review background information on PRBs as presented in the material from earlier ITRC PRB training courses. You can access archives of these trainings at http://www.clu-in.org/conf/itrc/advprb_032102/ and http://www.clu-in.org/conf/itrc/prb_031902/. Three other documents produced by the ITRC PRB team are also available for review. They can be downloaded from the ITRC Web site under 'Guidance Documents.'