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Precious Groundwater in Drought Areas Threatened by Uranium Mining

Why Are We Allowing Uranium Miners to Pollute Groundwater in Drought Zones?
Uranium mining threatens aquifers that could provide the drought-stricken West with emergency water supplies. BRIAN PALMER OCT 16, 2015 Mining uranium, the fuel for nuclear reactors, is a dirty business. Following World War II, mining companies extracted millions of tons of uranium from Navajo tribal lands in the West, contaminating homes and water supplies in the process. It went on for decades, and Navajo miners developed lung cancer at very high rates.

Today, even as the United States nuclear power industry struggles to survive, uranium mining continues. The techniques are more modern, but conservationists say the threat could be just as insidious: polluting water supplies in drought-ridden parts of the country where drinking water is already alarmingly scarce.

New rules proposed by the federal government last year could help reduce the threat—although industry is fighting to weaken them, along with its Republican allies in Congress. And critics say the proposed regulations might not be strong enough anyhow. Ironically, this might all be happening to extract a resource we barely need anymore—at the risk of one that we most certainly do……..

The industry must now work with what geologists call “roll-fronts.” These are relatively thin uranium deposits that formed deep underground over the course of thousands of years. Typically just 10 to 30 feet in height—too small to be harvested by human miners—the roll-fronts can only be extracted by chemical means.

The process used today is called in situ recovery, or ISR, mining. (Opponents use the more chemically descriptive phrase “in situ leaching,” or ISL.) The mining company drills four or five holes, called injection wells, and then pumps down a mix of an oxidizing agent (often hydrogen peroxide or simple oxygen) and water. Pressure from the constant influx of fluid forces the solution to percolate through the uranium-rich layer of Earth toward another hole, called the production well, which carries it up to the surface. At this point, the company reverses the chemical reaction that dissolved the uranium, using a separate chemical to precipitate the metal out of the water. The water, now stripped of most of the uranium, heads back into the well to continue the cycle…….

In reality, ISR mining isn’t so tidy, and the few peer-reviewed studies available suggest that leaching uranium out of rocks contaminates the surrounding groundwater for decades. As Western states deal with increasing levels of drought, that’s a problem…….

Remediation is water- and time-intensive, but does it work? The answer is pretty disturbing: No one knows. There have been only a handful of major studies on the efficacy of the uranium-mining remediation process.

One of the rare peer-reviewed studies, led by Colorado State University’s Thomas Borch and published in 2012, suggests that remediation isn’t particularly effective. Borch and his colleagues used public records to compare the pre- and post-mining water chemistry in a Wyoming well. The “baseline” measurement revealed a uranium concentration of 0.05 milligrams per liter. In February 1999, after eight years of remediation, the uranium concentration was 3.53 milligrams per liter, more than 70 times the pre-mining levels.

To put those numbers into further context, the EPA’s maximum acceptable concentration for uranium in drinking water is 0.03 milligrams per liter. The mining process therefore took water that, with some treatment, might have been safe to drink, and rendered it non-potable for generations.

“Reverse osmosis is good at taking salts out of concentration,” Borch says. “That’s a big deal, because salts ruin agricultural fields. But it can’t get uranium back to baseline levels.”

The aquifer’s problems aren’t limited to uranium. Borch’s study showed that, even after years of remediation, radium, arsenic, iron, selenium, barium, and several other contaminants remained high above EPA-recommended levels for drinking water……

the context in which ISR uranium mining is taking place. These are the factors that must be considered when deciding whether to write off aquifers for decades. Unfortunately, experts say, our laws aren’t consistent with the starkness of this reality.

EPA regulations state that any aquifer containing 10,000 milligrams of dissolved solids (typically salt) per liter of water is automatically not a candidate for drinking water and is open to industrial uses. Even at that level, though, you could make a case that we shouldn’t abandon those aquifers. Although seawater is typically above 35,000 milligrams of dissolved solids per liter, Saudi Arabia is turning hundreds of millions of gallons of it into drinkable water every day. It’s expensive and energy-intensive, but it’s possible.

The rules that apply to aquifers with less than 10,000 milligrams of dissolved solids per liter are largely discretionary. Legally, regulators can write off sub-10,000 quality aquifers only if they are isolated and offer no possibility whatsoever that they’ll be useful to humans in the future. That judgment, however, leaves substantial room for interpretation, and, in practice, energy companies tend to get whatever they want…….

Giving uranium miners access to these mines is akin to opening a Pandora’s box of pollution. Nuclear Regulatory Commission rules state that the uranium miner must return water quality in the aquifer to the levels they found before drilling. If the company proves it cannot achieve those levels, it can fall back on a less aggressive standard: making sure that uranium and other chemicals are reduced to the maximum levels set by regulation. And if even those levels are “not practically achievable,” the company can propose its own contaminant-concentration levels—whatever it believes is safe for the surrounding ecosystems and communities. This is known as the “alternative concentration limit,” or ACL.

In practice, there’s nothing “alternative” about the ACL. No uranium-mining company has ever returned an aquifer to pre-mining concentrations of uranium or other chemicals. Nor has a uranium miner managed to achieve the regulatory maximum levels intended as a fallback. In every single instance, the industry has resorted to the ACL. And the Nuclear Regulatory Commission has let them.

Does the U.S. even really need the uranium? Despite the enthusiasm of a few vocal supporters like Tennessee Senator Lamar Alexander or Arizona’s John McCain, the future of nuclear energy in the country is uncertain at best. It has been 19 years since a new domestic reactor came online. Due to safety concerns and cost overruns, the country largely gave up on nuclear in the 1980s.

So why the enthusiasm for ISR uranium mining? A strange form of forgetfulness swept across the country about 10 years ago. Call it nuclear amnesia. In the face of climate change, the world needed low-carbon energy, and there stood the nuclear industry, ready to let bygones be bygones. People decided to forgive—or at least forget—all the reasons we abandoned nuclear in the first place.

The delays and the cost overruns that plagued previous reactor projects were assumed, without any evidence, to be a thing of the past. Utilities submitted plans to build dozens of reactors. During this second honeymoon, widely referred to as the U.S. nuclear renaissance, uranium prices surged in anticipation of future demand.

The demand never materialized, and it probably never will. When financiers took a sober look at the case for nuclear reactors, they blanched. Almost all the planned reactors were abandoned, save four that are being built in South Carolina and Georgia. Predictably, all four are behind schedule and overbudget.

Unless the government comes in with massive subsidies, wiping out nuclear power’s inherent economic drawbacks, the industry appears to be dying in the U.S. The Clean Power Plan isn’t likely to provide those incentives. Many states can achieve the targets for less money—and with less risk—through energy efficiency and investments in wind and solar. The four new reactors currently under construction (if they are ever completed) cannot begin to compensate for the eventual decommissioning of the 100 or so existing reactors that has already begun. By mid-century, nuclear reactors are likely to contribute a negligible proportion of U.S. electricity, and demand for uranium will dive……..

The next few months will be decisive for uranium mining in the U.S. And more data is on the way, as professors Borch and Stone (who have secured the cooperation of a major mining company) prepare to release the largest-yet study on the effects of ISR mining on groundwater. The EPA rules will likely be finalized in late 2015 or early 2016. And a major lawsuit over the regulation of the ISR mining—in which NRDC is a party—is wending its way through the Nuclear Regulatory Commission’s Byzantine appeals system.

A study released this year predicted that the West would experience amegadrought during this century—a level of dryness not experienced since the pre-Columbian era. We may have to tell our grandchildren that we risked the one resource we knew they would desperately need, all so we could extract one we could easily have lived without.

This post originally appeared on Earthwire as “Hot Water” and is re-published here under a Creative Commons license. http://www.psmag.com/nature-and-technology/why-are-we-allowing-uranium-miners-to-pollute-groundwater-in-drought-zones

October 17, 2015 - Posted by Christina Macpherson | technology, Uranium, USA, water