Grand Canyon Waters Protected from Uranium Mining

On September 30, 2014, Judge David Campbell of the U.S. District Court for the District of Arizona upheld the twenty year moratorium against new uranium mines in and around Grand Canyon National Park much to the dismay of the mining industry. Uranium mining has a long, storied history in the American Southwest, a region of iconic natural beauty and sparse water.

Environmental groups, tribal nations, and river rats are embracing Judge Campbell’s decision, much like they did former Interior Secretary Ken Salazar’s declaration of the moratorium in 2009.

The Process and Risks of Uranium Mining

Like any hard rock mining process, uranium extraction requires immense amounts of water and poses significant risks to the environment and human health. Depending on the quality and depth of the ore, several different extractive methods may be employed, but all use massive amounts of water and result in chemical contamination from extracting and processing the ore. (The proposed mines and exploratory sites around the Canyon involved in this litigation, for example, were predicted to use over 300 million gallons of water.) Uranium is a radioactive mineral known to cause cancer. Other metals and minerals, such as selenium, molybdenum, arsenic, and nickel, commonly coincide with uranium deposits. These metals all pose significant health risks, especially when disturbed and concentrated at the surface. Mining activities disturb these elements and concentrate them in waste rock, tailing ponds, and wastewater. Water’s exposure to radioactive ore and wastewater pose significant risks to human health and the surrounding natural environment, including vegetation and animals.

Uranium and Water in the Canyon

The Grand Canyon region is home to some of the richest uranium deposits in the United States, in formations called breccia pipes. These pipes, 300 to 500 feet in diameter, extend thousands of feet into the ground. The uranium deposits around the Canyon were already being explored when President Teddy Roosevelt listed the Grand Canyon as a national monument in 1908. The industry’s heyday corresponded with the Cold War when uranium prices skyrocketed. Hundreds of ill-regulated mines disturbed land around the Canyon, but operators later abandoned or suspended many smaller mines as market demand for uranium waned. Only four mines remain active to this day (the moratorium does not prevent these active mines, but rather prevents further development), but industry pushed to overturn the moratorium and increase new production, despite a fall in uranium prices following the Fukushima fallout. Just north of the Grand Canyon, Pinenut Mine continues to produce uranium, but at a steep environmental price. An abandoned shaft contains millions of gallons of water contaminated with uranium at eighty times the safe limit for human consumption. It is unknown if this water has contaminated surrounding aquifers. Open-air evaporation ponds of wastewater and tailings are a death trap for birds and other wildlife at the mine site.

Because there is so much dependence on the Colorado River, interest in its safety extends far beyond Arizona’s state border. Nearly thirty million people from seven states rely on water from the Colorado River basin for industrial, municipal, agricultural, and recreational uses. Water utilities of Arizona, California, and Nevada expressed concerns that mining waste could enter the Colorado River via runoff and endanger their claims to the Colorado River. Multiple American Indian tribes, including defendant-intervenors in the district court action, the Havasupai and Haulapai tribes, have significant cultural and religious connection to the Canyon and its surrounding water. One aquifer underlying an abandoned uranium mine where tests shows dangerously elevated levels of radiation and hard mineral contamination is the Havasupai peoples’ sole source of drinking water.

Canyon Water Endangered by Proposed Mines

While water contamination is certainly a concern in any community, it is of particular concern around the Canyon because of the existing geology. The dissolved rates of uranium and related metals are naturally higher the Canyon watershed because of the minerals’ presence in the area. Judge Campbell used a USGS report that found Canyon waters contaminated with unsafe levels of uranium, selenium, and arsenic, particularly at sample points near old or suspended mines and exploratory uranium sites to inform his decision. The report was unclear as to the cause of the contamination. Whether the increased levels of chemicals in the water are the result of natural runoff and flooding, or the result of past mining activity in the area is still uncertain. The plaintiffs, a consortium of companies who all seek to operate new uranium mines around the Canyon, argued Secretary Salazar and the Department of Interior took an “overly cautious” stance in reaction to the uncertainty of the source of contamination, and the removal of nearly one million acres of land from mining activity was inappropriate. Judge Campbell, however, rejected this argument and reasoned that while the source of contamination may be uncertain, the potential impacts of such contamination are too great to risk.

Water contamination is not the only concern with industrial uranium mining in the Grand Canyon. The Department of Interior’s study of mining impacts prior to Secretary Salazar’s moratorium predicted that seven hundred exploratory claims and twenty six new uranium mines could be developed, consuming 316 million gallons of water. Springs, aquifers, and potentially even the Colorado River itself would provide the water for such activities. This substantial use of already low supplies of water in the desert could deplete drinking water sources for canyon communities and endanger the environment in the midst of existing and predicted drought conditions. Judge Campbell held the stakes were simply too high for the Canyon.

The Grand Canyon is a world heritage site, a source of cultural pride for the American Southwest, and the sacred birthplace of the Havasupai and the Haulapi peoples. Judge Campbell’s decision protects the unique watershed of the Grand Canyon from drastic water extraction and potentially severe fallout of radiation contamination from large-scale uranium extraction.


The title picture features the Orphan Mine in Grand Canyon National Park. This is just one abandoned copper-uranium mines in the park. The image is licensed under the Creative Commons Attribution 2.0 License to Alan Levine, who does not endorse this blog. 


Chrissy Pepino, Protecting the Grand Canyon against Uranium Mining, Earthjustice (2012),

Dana S. Ulmer-Scholle, Uranium – How is it Mined?, New Mexico Bureau of Geology and Mineral Res. (Aug. 4, 2014),

Press Release, Center for Biological Diversity, Feds urged to Suspend Grand Canyon Uranium Mine to Protect Water, Wildlife and People: BLM Fails to Respond to Groundwater Contamination at Pinenute Mine, (Aug. 4, 2014) available at

Press Release, Earthjustice, Court Upholds Grand Canyon Uranium Mining Ban, (Sept. 30, 2014) available at

Donald J. Bills, et. al., Breccia-Pipe Uranium Mining in Northern Arizona – Estimate of Resources and Assessment of Historical Effects, United states geological survey (Jan. 2011), available at

Yount v. Salazar, No. CV11-8171 DGC (Ariz. Dist. September 30, 2014), available at