A review on the use of permeable reactive barriers as an effective technique for groundwater remediation

This study provides a comprehensive review of the permeable reactive barrier (PRB) technique for groundwater remediation for a wide range of contaminants. We have discussed the fundamentals of installation, including site selection and design. Different PRB designs are discussed, including the funnel and gate, continuous trench, and sequential configurations. We have also discussed different methods for PRB optimization to achieve maximum removal rates of pollutants. The reactive mechanisms, which play a crucial role in the removal process, are reviewed in detail, for various types of reactive media. The effect of combining multiple materials for enhancing the performance of single and multiple PRB systems was also reviewed. Finally, we determined the optimization factors that contribute to the longevity of the various PRB designs to, ultimately, enhance groundwater remediation. With the correct design and appropriate selection of reactive materials, a PRB system could be highly effective in the remediation of groundwater contaminant plumes. Previous studies reported that the PRB could successfully treat groundwater contaminated with organics, heavy metals, and radioactive substances, including benzene, toluene, ethylbenzene, and xylene (BTEX), arsenic, lead, caesium-137, and uranium. Several reactive materials, including zero-valent iron, activated carbon, and zeolites, satisfy the characteristics required for groundwater remediation. In addition, we analysed the potential of new reactive materials, including sand, apatite, straw-based materials, gravel and mulch mixture, to remove different contaminants through the use of PRB systems.