Water has accumulated in Canyon uranium mine. Now what?
Ron Dungan , The Republic | azcentral.com
A wet winter and increased groundwater flow have raised water levels at the Canyon uranium mine near the South Rim of Grand Canyon National Park, stirring concerns among conservationists who fear the spread of uranium mines could contaminate water across the plateau.
The water levels at the Canyon mine were so high at one point last month that the mine’s operator had to spray water into the air to enhance evaporation and increase the amount of water it was hauling to its White Mesa Mill in Utah.
State regulators say they have not found any violations at the mine site and the mine’s operators say water levels have begun to drop.
Officials also downplay concern about polluted water escaping the site, where samples taken at the mine’s holding pond recently tested at 130 parts of dissolved uranium per billion. The Environmental Protection Agency considers anything above 30 parts per billion to be unsafe to drink.
A group of conservationists visited the mines last month and reported seeing mist from high-powered pumps blowing onto national forest lands.
“When we got there, we saw all this water being sprayed in the air and we thought, ‘Oh, that’s dust control,’ ” said Alicyn Gitlin, of the Sierra Club. They later learned that the company was trying to get water out of its evaporation pond.
The Arizona Department of Environmental Quality requires mines to control storm runoff and keep contaminated water in evaporation ponds.
But conservationists say the agency doesn’t do enough. They have also begun to point to a growing body of geological research indicating that wells, seeps and springs near the Grand Canyon may be connected, from the top of the rim to the Colorado River.
Conservation groups and the Havasupai Tribe, whose members live in the Grand Canyon, have worked unsuccessfully to block the mine, as well as a proliferation of uranium mining claims near the North Rim.
Curtis Moore, a spokesman for Energy Fuels Resources Inc., the mine operator, said in an email that the groundwater flows in the shaft have slowed recently, and evaporation pond levels have dropped.
Storm water runoff, groundwater fill pond
The company notified the ADEQ in January that a lined evaporation pond that captures storm-water runoff was getting full because of the wet winter weather. At the same time, groundwater began flowing out of the upper section of the shaft from a part of the aquifer that sits nearer to the surface.
In January, Energy Fuels requested permission for higher water levels in its evaporation pond, to within one foot of the top of the pond, and indicated it would start using wastewater evaporation pumps known as Land Sharks. The machines can shoot water at a rate of up 110 gallons per minute, with water pressure at 100 PSI, according to the website for Resource West, which manufactures them.
“They were just blowing water into the air,” said Roger Clark, of the Grand Canyon Trust, who visited the site about a week ago.
By March 2, Energy Fuels wrote ADEQ to report that recent snowfall, along with “continued inflows” from groundwater in the shaft, prompted the company to add at least one more truck to its fleet to haul water away from the site.
On March 12, a Sunday, members of the Sierra Club said they saw mist blowing away from the mine.
On March 20, an ADEQ inspector visited the site and said there did not appear to be any violations, and that mist from the Land Sharks was “not drifting outside the property line.”
‘Actively monitoring the situation’
Since the Sierra Club visit, the Forest Service has sent people out to the mine daily, said Jacqueline Banks, a spokeswoman for Kaibab National Forest.
“We’ve been actively monitoring the situation,” Banks said.
Discharge from the aquifer has gone down from 18 gallons per minute to 8 gallons per minute, said Trevor Baggiore, a water quality director for ADEQ.
The department also monitors air quality outside the mine for dust, soot, smoke, particulate matter and uranium. All were well within safe levels, said Timothy Franquist, an air quality specialist for ADEQ.
Baggiore said that the pond levels were getting back to around two feet.
Mining industry advocates say that uranium mines are small, “dry” and pose no threat to drinking water.
Clark pointed out that Pinenut Mine, north of the Colorado River, filled with water when it was on standby, and that encountering water in the upper reaches of the aquifer shows how little geologists know about what lies underground.
“They are assuming that it’s a trapped body of water. And once it’s gone they can get back to mining,” he said. “But they don’t know that for sure.”