With a half-life of 4.5 billion years, uranium's toxic legacy of contamination will always be with us. The Colorado Plateau’s communities and landscapes continue to be poisoned by our region’s uranium legacy, which includes thousands of abandoned mines and numerous mill sites, along with polluted soil, air, and water.
The nuclear race of the 1950s launched a uranium frenzy, and thousands of prospectors rushed to the Southwest in search of the yellow dirt. By 1955, there were about 800 mines producing high grade uranium ore on the Colorado Plateau. Atomic towns popped up throughout the West, only to become ghost towns when the market dropped in the late 1980s.
Another surge in the mid-2000s prompted mining claims alarmingly close to the Grand Canyon’s north and south rims. Uranium's boom and bust cycle has left thousands of abandoned mines in need of clean-up, while many others hang in limbo waiting for uranium prices to spike again.
Hoodoos, spires, cliffs, and canyons define the Colorado Plateau, but the landscape's beauty obscures the mining resources that lie below the surface. Uranium deposits sit deep within the inner folds of sandstone, siltstone, and mudstone layers that characterize the Southwest. Breccia pipes, one of the most common types of uranium deposits here, typically range from 100 – 400 feet in diameter and can be up to 3,000 feet deep!
Open pit mining: strips away topsoil and rock above the uranium ore
Underground mining: extracts rock through a tunnel or other opening
Chemical dissolution: uranium ore deposits are dissolved into a solution and extracted
After uranium is mined, it must be milled to remove the uranium from the ore. At the mill, ore is crushed, ground, and treated with chemicals to dissolve the uranium into a solution. The final product, commonly referred to as “yellow cake,” is packed and shipped in casks.
The U.S. has only one operating conventional uranium mill – the White Mesa Uranium Mill – located in southeastern Utah.
To encourage a pro-nuclear culture, some atomic towns hosted "Miss Uranium" pageants and opened "Uranium Cafés" and “Uranium Drive-ins,” while others touted the benefits by wearing uranium medallions. The nation has come a long way in understanding the health and environmental threats posed by uranium, but the boom and bust cycle of uranium mining is stuck on repeat. Market prices spike; mines resume operation. Prices tank, and mines shut down.
The Lower Colorado River Basin – 40 million people and 4 million acres of farmland – depends on clean, safe water from the Colorado River. But, research shows at least one uranium mine in the watershed has contaminated an aquifer with uranium concentrations in excess of EPA drinking water standards.
Uranium mining and milling contaminate soil, with cascading effects for entire ecosystems. Plants drop their leaves too early, and changes in vegetation lead to increased risk of wildfire in an already too-dry environment. The USGS has found evidence of uranium and arsenic concentrations in soil up to 10 times greater than background levels at mines near Grand Canyon National Park.
America may have won the Cold War, but a decade after the collapse of the Sovet Union, Utah is left with a toxic legacy that has killed and sickened untold thousands of uranium miners and mill workers, contaminated water supplies for generations to come, and infected an otherwise stunning redrock landscape with millions of tons of radioactive mill tailings..."
– Jerry D. Spangler (author) and Donna Kemp Spangler (author and communications director, Utah Department of Environmental Quality)
Uranium is toxic to humans and accumulates in bone, liver, kidneys, and reproductive tissues. Exposure to low levels of uranium radiation can cause cancer, reduce fertility, and shorten lifespans. Radon-222, the leading cause of lung cancer in the United States, is emitted from both uranium mines and mills.
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