Remediation of Explosives in Groundwater Using a Zero-Valent Iron Permeable Reactive Barrier

Abstract : This final technical report documents the demonstration of a zero-valent iron (ZVI) permeable reactive barrier (PRB) for the removal of explosives from groundwater. The demonstration was conducted at the Cornhusker Army Ammunition Plant (CAAP) near Grand Island, Nebraska. The primary objective of this project was to evaluate the cost and performance of the ZVI PRB Performance of the PRB was evaluated by monitoring groundwater concentrations of explosives downgradient of the PRB. Data obtained during the demonstration were used to assess the costeffectiveness of this approach for long-term removal of explosives from groundwater. The primary advantages of ZVI PRBs for groundwater remediation are: 1. No aboveground remediation equipment is required 2. Rapid conversion of groundwater to reducing conditions 3. Low operation and maintenance costs 4. Long-lasting (>20 years) in situ treatment 5. Cost-effective. The cost-effective use of ZVI PRBs 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.