AWWA WQTC69375

Nitrate contamination of drinking water supplies is a significant concern to water systems throughout the world, predominately in areas with significant agricultural activity. Perchlorate contamination, while not as widespread, is also a source of significant public health concern. Biologically active permeable reactive barriers have been successfully employed to treat both of these contaminants. Unlike some other biological processes, permeable reactive barriers provide stable operations over the long term with minimal, if any, need for operator intervention. Permeable reactive barriers are a continuation of recent trends in the drinking water profession that recognize the benefits of subsurface processes to reliably and inexpensively remove pathogens, organic contaminants, and provide other water quality benefits. The most common treatment processes considered for nitrate and perchlorate removal are similar. These processes include ion exchange, electrodialysis, and reverse osmosis. In addition, engineered above-grade biological treatment processes are sometimes considered for nitrate and perchlorate treatment. Ion exchange, reverse osmosis, electrodialysis, and biological denitrification have all been applied at full-scale for the removal of nitrate from drinking water. Includes 30 references, tables, figures.