A PERMEABLE REACTIVE BARRIER (PRB) IS A SUBSURFACE EMPLACEMENT OF REACTIVE MATERIALS THROUGH WHICH A DISSOLVED CONTAMINANT PLUME FLOWS UNDER NATURAL OR INDUCED GRADIENT. AST has completed numerous PRB projects via direct-push injection and conventional continuous trench application to address petroleum hydrocarbon and chlorinated solvent plume migration. A passive PRB is often used as an alternative to site wide remediation to quickly protect sensitive features, bisect a plume, and/or reduce total remediation cost.
A successful PRB requires a comprehensive mass flux characterization. The design should be based on a thorough understanding of subsurface hydraulic and mass distribution heterogeneity rather than on average values.