Global Perspectives on Groundwater Decontamination: Advances and Challenges of the Role of Permeable Reactive Barriers

Ensuring access to clean water for drinking, agriculture, and recreational activities remains a global challenge. Groundwater, supplying approximately 50% of domestic water and 40% of agricultural irrigation, faces increasing threats from climate change, population growth, and unsustainable agricultural practices. These factors contribute to groundwater contamination, notably nitrate pollution resulting from excessive fertilizer use, which poses risks to water quality and public health. Addressing this issue demands innovative, efficient, and sustainable remediation technologies. Permeable reactive barriers (PRBs) have emerged as promising solutions for in situ groundwater treatment, using reactive media to transform contaminants into less toxic forms. PRBs offer advantages like low energy consumption and minimal maintenance. This study uses bibliometric analysis to explore the scientific production of PRBs for nitrate remediation, revealing research trends, key focus areas, and significant contributions. It included 141 articles published from 1975 to 2023. Early research focused on basic mechanisms and materials like zero-valent iron (ZVI), while recent studies emphasize sustainability and cost-effectiveness using low-cost materials such as agricultural byproducts. The findings highlight a growing focus on the circular economy and the need for more in situ studies to assess PRB performance under varying conditions. PRBs show significant potential for enhancing groundwater management and long-term water quality in agricultural contexts.