Researchers Use Bacteria to Reduce Uranium to Safe Levels
New results show a promising technique for cleaning up uranium left from 50 years of weapons programs by harnessing the powers of microbes already in the soil.
While the Cold War ended decades ago, its legacy will live for centuries in toxic waste. In remote corners of the country from Tennessee to the Pacific Northwest, dozens of federal laboratories struggle to clean up contaminants left from 50 years of weapons programs. New results show a promising technique for cleaning up uranium from some of the most severely contaminated areas by harnessing the powers of microbes already in the soil.
"Toxic uranium often is found in ground water at places where uranium was either mined or enriched to make weapons," says Craig Criddle, a professor of civil and environmental engineering at Stanford. "This uranium-contaminated water can migrate into surface waters, where it becomes a threat to organisms and water supplies. Excavation of contaminated soil or pumping and treating the water are prohibitively expensive and lead to additional disposal issues. An alternative is to stimulate naturally occurring subsurface microorganisms that can convert the dissolved uranium into a solid form that is not susceptible to transport by water."