Remediation of TNT and RDX in Groundwater Using Zero-Valent Iron Permeable Reactive Barriers

This Cost and Performance Report documents the demonstration of a zero-valent iron (ZVI) permeable reactive barriers (PRB) for the removal of explosives from groundwater. The demonstration was conducted at the Cornhusker Army Ammunition Plant (CAAP) near Grand Island, Nebraska. Performance of the PRB was evaluated by monitoring groundwater concentrations of explosives downgradient of the PRB. Data obtained during the demonstration were used to demonstrate the cost-effectiveness of this approach for long-term removal of explosives from groundwater. The primary advantages of ZVI PRB for groundwater remediation are: *No aboveground remediation equipment required *Rapid conversion of groundwater to reducing conditions in which explosives are degraded *Low operation and maintenance costs *Long-lasting (>20 years) in situ treatment *Cost-effective. The cost-effective use of ZVI PRB may be limited by the depth to groundwater and the ability to install the PRB in some geologic media. However, at sites without these physical constraints, the approach can be highly effective.