Uranium Contamination Plagues Aquifers Serving Nearly 2 Million

Uranium levels are around 180 times the safe limit in aquifers serving nearly 2 million people in the Midwest and California, according to new research.

A new study, published in the August issue of Environmental Science and Technology Letters and partially funded by the U.S. Geological Survey, crunched data from 275,000 groundwater samples. The findings were as follows:

Groundwater geochemical data collected from two major U.S. aquifers, High Plains and Central Valley, revealed naturally occurring groundwater uranium exceeding the U.S. Environmental Protection Agency maximum contaminant level (MCL = 30 μg/L) across 22375 km2, where 1.9 million people live.

Conducted by scientists at the University of Nebraska-Lincoln, the study also tracked nitrate levels, and found they correlated strongly with uranium levels.

“The study reports that 78 percent of the uranium-contaminated sites were linked to the presence of nitrate, a common groundwater contaminant that originates mainly from chemical fertilizers and animal waste. Nitrate mobilizes naturally occurring uranium through a series of bacterial and chemical reactions that oxidize the radioactive mineral, making it soluble in groundwater,” the communication office at the University of Nebraska–Lincoln explained in an announcement.

“These results indicate that nitrate, a primary contaminant, should be considered as a factor leading to secondary groundwater uranium contamination in addition to the recognized role of alkalinity and calcium,” the study said.

Karrie Weber, a researcher who worked on the study, explained the significance of the findings.

"It needs to be recognized that uranium is a widespread contaminant," she said. "And we are creating this problem by producing a primary contaminant that leads to a secondary one."

The aquifers in question provide water for a sixth of U.S. farmland, according to RT.

"When you start thinking about how much water is drawn from these aquifers, it's substantial relative to anywhere else in the world. These two aquifers are economically important -- they play a significant role in feeding the nation -- but they're also important for health. What's the point of having water if you can't drink it or use it for irrigation?" Weber said, per RT.

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