Oct 28, 2008
By Kevin Killough
Staff writer
GRANTS, NM — In about a month, the largest uranium tailings pile in the country will be officially reclaimed, making it safe for 1,000 years without any maintenance. The pile rises like a mesa from the floor of the Ambrosia Lake valley. Heavy machinery continues to climb the rock-covered slopes, finishing up the final tasks before the site can be turned over the Department of Energy.
The designers of the $100 million project went to great lengths to ensure the safety and security of the site. Even if it rained 21 inches in 24 hours, which would destroy Grants and leave Ambrosia Lake under 15 feet of water, the public wouldn’t need to worry about contamination from the tailings pile.
“If you see a guy building an ark, you want to come to the tailings pile,” said Terry Fletcher, president of Rio Algom LLC, who has overseen the reclamation project. It’s a highlight of his career in mining, milling and reclamation that spans 36 years.
Fletcher wants the public to know of the accomplishment, because he says that a lot of people are under the mistaken impression that uranium companies abandoned the toxic tailings piles. In fact, every single mill and tailings pile has been reclaimed or is in the process of being reclaimed, he said.
Tailings piles are common to many types of mining.
Chemical solutions are used in the milling process to separate the desired mineral from the mined ores. The remaining moist sand is left in piles. If not properly contained, they can be dangerous for the public and environment. Uranium tailings have the added hazard of radon gas emissions.
Today, mills are much more regulated, and processes prevent the contamination that has left uranium mining with a bad reputation. Even though no companies are making money off uranium milling in the state, Rio Algom, in a partnership with Kerr-McGee, swallowed the cost of the reclamation as part of what Fletcher says is the companies’ policy of sustainable development.
“It’s what responsible mining companies do,” Fletcher said.
A bridge across the highway stands as a testament that uranium companies today operate with an eye toward safety first. After assessing the potential for an accident with earth moving equipment crossing the road, the company decided to build a $1 million bridge to use during the reclamation processes. No government regulations required this.
“It’s just one of the things the company does that it doesn’t have to,” Fletcher explained.
The bridge pales in comparison to the massive tailings reclamation project. First the tailings were moved on top of a three-layer lining. The middle layer is a mesh that detects any leakage moving between the top and bottom layers. After reclamation, the DOE will constantly monitor the detection system for any leaks into the groundwater and stop any problems in the unlikely event they should occur.
On top, the pile was covered with a clay layer that is 20-feet thick on the slopes. The 30-foot high slopes were then covered with thick rock layers. The largest rocks were placed at the bottom of the slope where the water will be running the fastest. This will stop the sides from being eroded away. Finally, the pile will be covered with dirt, and as vegetation grows over time, the pile will look almost like a natural formation.
“It’ll look like a flatter mesa than nature made,” Fletcher said.
The piles give off about two-thirds less radon emissions than what occurs naturally in this part of the state. This month, Fletcher said, the Nuclear Regulatory Commission inspected Rio Algom’s pile and gave it an A+ rating.
The mines that supplied the mill with ore have also been reclaimed at about $50,000 each. There’s not much to see at a reclaimed mine. At one time large head frames loomed over the shaft, lowering and raising men and materials. Now, reclaimed mines are just an area of grass and maybe a tree where cows graze.
“That area there you’re looking at was one of the major mining sites in New Mexico,” Fletcher said, pointing to what looks like just a part of the landscape.
Other problems created by the obsolete practices of past mining continue to require cleanup efforts, especially the many “dog holes” that independent miners left behind. The groundwater contamination from some tailings piles is a whole other cleanup effort. But the completion of the Rio Algom pile reclamation is a good sign that past mistakes are on their way to being corrected.
Kevin Killough blogs at http://gallupnm.blogspot.com
http://www.gallupindependent.com/2008/10october/102808tailings.html
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