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For Immediate Release, February 18, 2010

Contact:  Taylor McKinnon, Center for Biological Diversity, (928) 310-6713
Sandy Bahr, Sierra Club, (602) 999-5790
Roger Clark, Grand Canyon Trust, (928) 774-7488

Government Study: Elevated Uranium Levels in Grand Canyon's Watershed
Exploration and Mining Sites Consistently Exceed Background Levels

GRAND CANYON NATIONAL PARK— A series of studies released today by the United States Geological Survey show elevated uranium levels in wells, springs, and soil in and around uranium exploration and mining sites within the watershed feeding Grand Canyon National Park and the Colorado River. The agency conducted the monitoring to provide information for an environmental impact statement that is analyzing a proposed 20-year mineral withdrawal that would protect nearly 1 million acres of public land surrounding Grand Canyon National Park from future mining activities.

“These reports demonstrate unequivocally that uranium mining should not proceed in these environmentally sensitive lands,” said Stacey Hamburg of the Sierra Club’s Grand Canyon Chapter. “Contaminated lands and waters around the Grand Canyon are not what we want for the future of northern Arizona. Cleaning up contaminated sites should be the government’s first priority.”

Elevated uranium levels consistently exceed natural background levels in and around exploration and old mining sites – sometimes, as in the case of the Kanab North mine, by as much as 10 times. Elevated uranium levels were also detected near the old “Hack” uranium-mine complex, which the Bureau of Land Management actively promotes on its Web site as a model of good mine reclamation (see video here). Reclaimed in the 1980s, the mines are located in Hack Canyon, a tributary to Kanab Creek and the Grand Canyon and Colorado River.

“Uranium mining has already contaminated lands and waters in and around Grand Canyon, and today’s research confirms that new uranium mining would threaten aquifers that feed Grand Canyon’s springs, the Colorado River, and nearly 100 species of concern,” said Taylor McKinnon of the Center for Biological Diversity. “These risks aren’t worth taking – and they’re risks neither the government nor industry can guarantee against.”

Elevated uranium levels were also detected at another nearby old mine that the Bureau has said it will allow to reopen without updating 1980s-era federal environmental reviews. The first such opening, of Denison Mines’ Arizona 1 mine, provoked a lawsuit in November from conservation groups seeking updated reviews.

Fifteen springs and five wells exhibited dissolved uranium concentrations greater than the Environmental Protection Agency maximum for drinking water; hydrogeologists have warned that new mining could deplete and pollute water in aquifers and connected springs. Today’s report concludes that: “Uranium mining within the watershed may increase the amount of radioactive materials and heavy metals in the surface water and groundwater flowing into Grand Canyon National Park and the Colorado River, and deep mining activities may increase mobilization of uranium through the rock strata into the aquifers. In addition, waste rock and ore from mined areas may be transported away from the mines by wind and runoff.”

“The USGS research confirms that mining uranium within Grand Canyon watersheds risks permanently polluting waning water supplies for 25 million people and arid ecosystems. There are some places where mining should not occur, and the Grand Canyon is one of them,” said Roger Clark of the Grand Canyon Trust.

Last week the Center for Biological Diversity sued the U.S. Bureau of Land Management for illegally withholding public records relating to uranium mines immediately north of Grand Canyon National Park. The Bureau is withholding the vast majority of eight linear feet of responsive records despite directives from the Obama administration requiring the agency to respond to information requests “promptly and in a spirit of cooperation” and to adopt a “presumption of disclosure” (see Obama’s Freedom of Information Act memo to federal agencies here).

All of today’s reports can be downloaded here:

Summary of Research Findings (From USGS)

•       The area proposed for withdrawal is estimated to contain about 163,000 tons (about 326 million pounds) of uranium oxide (U3O8), which is about 12 percent of the estimated total undiscovered uranium in northern Arizona (1.3 million tons or 2.6 billion pounds). For comparison, the United States consumes about 27,550 tons (55 million pounds) of uranium oxide each year in its reactors; most of it comes from Canada, Australia, and Russia.
       Soil and sediment samples were analyzed for six sites that experienced various levels of uranium mining in Kanab Creek area north of Grand Canyon National Park, including mined and reclaimed sites, mined sites currently on standby, and sites that were exploratory drilled but not mined. Uranium and arsenic were two elements consistently detected in the areas disturbed by mining in values above natural background levels.
       Analysis of historical water-quality data for more than 1,000 water samples from 428 sites in northern Arizona shows that dissolved uranium concentrations in areas without mining were generally similar to those with active or reclaimed mines. Sixty-six percent of the sampled sites showed low dissolved uranium concentrations (less than 5 parts per billion). Ninety-five percent of the sampled sites had dissolved uranium levels of less than 30 parts per billion, the Environmental Protection Agency maximum for drinking water.
•       Samples from 15 springs and 5 wells exhibited dissolved uranium concentrations greater than the Environmental Protection Agency maximum for drinking water. These springs and wells are close to or in direct contact with mineralized ore bodies, and concentration levels are related to natural processes, mining, or a combination of both factors.
•       Almost 100 plants and animals identified by the State of Arizona or other land managers as species of concern inhabit the area proposed for withdrawal. Because uranium and its byproducts such as radon can affect survival, growth, and reproduction of plants and animals, USGS scientists identified exposure pathways (for example, ingestion or inhalation) for these species of concern.


Spikes in uranium prices have caused thousands of new uranium claims, dozens of proposed exploration drilling projects, and proposals to reopen old uranium mines adjacent to the Grand Canyon. Renewed uranium development threatens to degrade wildlife habitat and industrialize now-wild and iconic landscapes bordering the park; it also threatens to deplete and contaminate aquifers that discharge into Grand Canyon National Park and the Colorado River. The Park Service warns against drinking from several creeks in the canyon which exhibit elevated uranium levels in the wake of past uranium mining.

These threats have provoked litigation; legislation; and public protests and statements of concern and opposition from scientists, city officials, county officials – including from Coconino County – former Governor Janet Napolitano, state representatives, the Navajo Nation, and the Kaibab Paiute, Hopi, Hualapai and Havasupai tribes, the Metropolitan Water District of Southern California, and the Southern Nevada Water Authority, among others. Polling conducted by Public Opinion Strategies shows overwhelming public support for withdrawing from mineral entry the lands near Grand Canyon; Arizonans support protecting the Grand Canyon area from uranium mining by a two-to-one margin.

The Interior Department in July 2009 enacted a land segregation order, now in force, and proposed a 20-year mineral withdrawal, which is now being analyzed, for one million acres of public land surrounding Grand Canyon National Park. Both measures prohibit new mining claims and the exploration and mining of existing claims for which valid existing rights have not been established. The Bureau of Land Management has failed to produce any documents demonstrating the establishment of valid existing rights for the Arizona 1 mine or other mines around Grand Canyon. The United States Geological Survey’s monitoring results that were released today are to inform the aforementioned analysis of the proposed mineral withdrawal.

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