LIMESTONE-BASED MATERIAL FOR ARSENIC REMOVAL FROM DRINKING WATER

The U. S. Environmental Protection Agency (EPA) has announced that the Maximum Contaminant Level (MCL) for arsenic will be lowered to 10 ppb by 2006. Current remediation technologies are expensive. This will result in increased economic pressure on rural communities with high levels of arsenic in their drinking water. Thus, lowering of the standard has spurred the development of a novel remediation technology that has shown the ability to reduce arsenic in drinking water at the source, with the added benefit of low-cost disposal of a stable and benign waste product in ordinary landfills. Phase I of this project focused on understanding the physical and geochemical processes that govern arsenic retention and transport in ground water, with emphasis on removal by limestone. The efficiency of the process under real-world conditions and the long-term stability of the resulting waste product were examined. Phase II research and development will produce, evaluate, and demonstrate prototype cartridges for point of entry (POE) and point of use (POU) systems and benchmark competing technologies. As a precursor to commercialization and certification, field trials with the cartridges will be conducted on a well in the community of Keystone, South Dakota in 2005.