In March, Utah’s legislature broke the cycle of not-in-my-back-yard politics and changed the law to allow storage in Utah of the nation’s depleted uranium stockpile. In the short term, this is wholly admirable and beneficial. In the long term, it’s neither. This requires some explanation, so let's do the numbers.
In 2000, a DOE study concluded that a shallow landfill was sufficient for storage of the nation’s three-quarter million tons of depleted uranium. This surprised some because for 40 years the growing global consensus for the long-term isolation of nuclear waste has been a deep repository. But for uranium, a shallow landfill makes sense. The uranium mine tailings being moved from the banks of the Colorado River near Moab to a landfill 30 miles north illustrates this. Leaching the entire 7,000 metric tons of uranium from this landfill into the Colorado (flow rate of 20 trillion liters per year) over a dozen years would leave the river EPA-safe (under 30 micrograms uranium per liter) for drinking, irrigation and for its endangered fish population. The fate of shallow uranium oxides, stored or natural, is that if they can be wetted, they eventually dissolve, run off, and find the sea. This is why the oceans already contain 10,000 times the uranium in our stockpile. And this is why a landfill is a good design for uranium. Anywhere, that is, but in the Great Basin where water does not drain to the sea.
Only in the Great Basin will the uranium from our planned landfill always remain at toxic levels, whether wet or dry. Again, let's do the numbers. The Great Basin alternates between wet, highly erosive-corrosive saline environments, and dry, dusty periods. Imagine a wet period with the Great Salt Lake swollen to 700 trillion liters, 20 times its current volume, but one-fifteenth its maximum capacity, that of Lake Bonneville. Dissolving our 700 billion gram stockpile would put the lake at a milligram uranium per liter, over 30 times the EPA safe drinking water level. If we evaporate the dissolved uranium stockpile to an area the size of the current Great Salt Lake (4400 square kilometers) we are left with 160 grams of uranium dioxide dust per square meter of ground. A breeze lofting 10 percent of this dust 100 feet creates a uranium cloud concentration of 530 milligrams per cubic meter — over 100 times greater than was found to cause lung tissue damage and cancer in beagle dogs.5 comments on this story
In those beagle uranium dust inhalation studies, done 50 years ago, the uranium lodged deep in the lung, in the alveoli, where gas exchange takes place. Uranium accumulated to 0.2 percent of lung tissue mass within a year, more than half of which remained in place 15 months after the dust inhalation was stopped. The uranium decay product, a charged helium nucleus traveling 20 million miles per hour, brought to a dead stop in a 10th-millimeter in the alveoli, does significant cell damage, literally taking our breath away. From the absorbed dose and its long residence in the lung it’s not surprising it caused pulmonary edemas and adenocarcinomas at rates over 50 times greater than occur spontaneously in beagles.
We might imagine someone flying over this future Great Basin measuring uranium radiation intensities 500 times greater than everywhere else and wondering why; why would anyone poison this beautiful basin? Why, when they could have safely landfilled the depleted uranium anywhere on the other 95 percent of American soil, why chose the one place, the Great Basin, where it’s probably unsafe?