Study Finds Uranium Seeps into Two Major U.S. Aquifers

Researchers have found that about 2 million Americans in the Great Plains and central California are living close to sites that far exceed federal safety guidelines for uranium levels.

A recent study conducted by the University of Nebraska-Lincoln found uranium levels in the High Plains and Central Valley aquifers, two of the country’s most significant sources of drinking water and irrigation, are far above thresholds set forth by the Environmental Protection Agency.

The research showed that water in the High Plains aquifer, the largest in the United States, had uranium levels as high as 89 times the EPA-established standards. The water in California’s Central Valley aquifer, a source of irrigation for one of the country’s most important agricultural hubs, showed some uranium levels that were 180 times the guidelines set forth by the EPA.

Uranium is an element whose isotopes were famously used in the production of atomic bombs. Past studies have shown long-term exposure to water tainted by uranium can lead to high blood pressure and kidney damage, according to a news release accompanying the Nebraska study.

The researchers found the uranium contamination in most of the 275,000 water samples they collected was directly tied to nitrate, a more common water polluter that is found in chemical fertilizers and animal waste. The scientists say that nitrate interacts with the uranium that’s naturally present in the ground in a way that makes the material dissolve in groundwater.

About 78 percent of the contaminated sites had nitrates present, the study indicated. The researchers said the data indicated that the uranium levels weren’t predominantly the result of mining or any kind of nuclear fuel, but rather the reactions between nitrate and the element.

“It needs to be recognized that uranium is a widespread contaminant,” one of the Nebraska study’s researchers, Karrie Weber, said in a statement accompanying the research. “And we are creating this problem by producing a primary contaminant that leads to a secondary one.”

The researchers said that facilities to treat water can cost seven figures, which makes it hard for some smaller municipalities to buy them. And there are some people who receive their water from private wells and don’t tap into any kind of regulated municipal water system.

The Associated Press reported Monday that the uranium contamination has been so widely underreported that some people living in the affected areas didn’t even know it was an issue.

The news agency said it conducted its own tests on the private wells of five homes near Modesto, California, where officials spent $500,000 on upgrades to its water system that were designed to bring down uranium levels. The report indicated none of the homeowners knew uranium even had the potential to be a water pollutant, yet two of the five wells showed dangerous levels of it.

The High Plains aquifer supplies drinking and irrigation water to eight states from South Dakota to Texas, according to the Nebraska study. The Central Valley aquifer is a major water source for California and the state’s vital agriculture industry, which the state Department of Food and Agriculture said produces half of America’s domestically-grown fruits, nuts and vegetables. In all, the department said California growers and ranchers got $54 billion for last year’s products.

“When you start thinking about how much water is drawn from these aquifers, it’s substantial relative to anywhere else in the world,” Weber said in a statement. “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?”