UNL study shows nitrates pull uranium from soil and into groundwater - KETV Omaha

UNL study shows nitrates pull uranium from soil and into groundwater

Those underground water sources include the High Plains Aquifer beneath most of Nebraska, covering Lincoln too.

Could uranium be in your groundwater?

That is the question the University of Nebraska in Lincoln is answering with a recent study exploring ties between nitrates in the ground and the radioactive element. The results are alarming, but not hopeless.

If you have ever thought about what goes into your water, UNL's microbiology program director Dr. Karrie Weber, has spent the last decade of her career getting her feet wet doing just that.

In 2015, Weber led a study that found aquifers with high nitrate contamination also contain uranium concentrations that blow past Environmental Protection Agency thresholds. That should be concerning for certain well owners.

"Anyone that might be drawing groundwater from shallow wells. So wells that might be less than a hundred feet deep," said Weber, who is the principal investigator of UNL's Nitrate-Stimulated Uranium Mobilization Study.

Those underground water sources include the High Plains Aquifer beneath most of Nebraska, covering Lincoln too.

"Uranium just gets deposited. When we can think about perhaps in the Platte River, so over time, it collects in the sediments," Weber said.

What Weber and her team did not know was whether nitrates and uranium had any cause-and-effect relationship. So they set out on another study: asking whether these nitrates, commonly found in fertilizers and animal waste, could transport naturally occurring uranium into groundwater.

To get good results, researchers went out to Alda, Nebraska, and took two, two-inch-wide cylindrical cores of sediment 60 feet deep from an aquifer site. Those soil samples, they knew, would contain traces of uranium since the site is adjacent to the Platte River.

"When we open this up, we'll immediately place the core inside of the anaerobic glove bag," Weber said.

Taking out oxygen preserves the natural conditions between nitrates and uranium. By adding nitrate-infused water through the sediment, the team gets to see which elements get drawn out with the liquid. The results had a ripple effect: nitrates carried with it 85 percent of the uranium in the soil compared to just 55 percent with plain water.

"It's that nitrate is promoting the conversion of uranium from a solid mineral that's buried in the sediment to another state that will be freely mobile in the water," Weber said.

So what does this all mean for you? High uranium concentrations can cause kidney damage in humans, especially if we drink it often in water. Certain areas of the High Plains Aquifer saw uranium levels up to 89 times the EPA threshold. Northeast Nebraska residents, especially along the Platte River, should be most aware.

The Nebraska Department of Environment and Energy says all community public water systems are required to meet drinking water standards with routine monitoring for nitrates and uranium. In a statement, they say residents with private wells should "conduct their own sampling schedule to monitor water quality."

"If uranium is high, you measure your well water and it's above the 30 parts per billion, you would want to get a treatment system in your home," Weber said.

For now, Weber and her team will keep diving into their research and informing the public that when it comes to water, clarity is key.

Chemical runoff is a problem natural resource directors from across the state are scrambling to find a solution.