(AP)—Back-to-back accidents and a never-supposed-to-happen above-ground radiation release that exposed at least 13 workers have shuttered the U.S. government's only deep underground nuclear waste dump indefinitely.
They have also raised questions about a cornerstone of the Department of Energy's $5-billion-a-year program for cleaning up legacy waste scattered across the U.S. from decades of nuclear bomb making.
The problems also highlight a lack of alternatives for disposing of tainted materials like tools, gloves, glasses and protective suits from national labs.
With operations at the Waste Isolation Pilot Plant on hold, so are all shipments, including the last of nearly 4,000 barrels of toxic waste that Los Alamos National Laboratories has been ordered to remove from its campus by the end of June.
The presence of that waste, some of which was dug up from decades-old, unsealed dumps in the northern New Mexico mountains and is now stored outside with little protection, came to the public's attention three years ago as a massive wildfire lapped at the edges of the sprawling lab property.
Sen. Tom Udall says getting the rest of the waste off the mesa before wildfire season begins is "paramount," but that it is too soon to know if a temporary alternative site for storing the waste needs to be found.
Also on hold are tests to see if the dump can expand its mission to take more than so-called lower level transuranic waste from the nation's research facilities, including hopes by DOE that it can ship hotter, liquid waste from leaking tanks at Washington state's Hanford nuclear waste site.
Government officials, politicians, the contractors that run the mine and local officials all say it is too soon to speculate on what the short- or long-term impacts of the of the shutdown might be, or where else the toxic waste would go. And they emphasize that all the safety systems designed to react to worst-case scenarios like a ceiling collapse worked.
"A lot of people are just jumping up and down and wanting us to shut down," said Farok Sharif, president of the Nuclear Waste Partnership that runs WIPP. "But that's not the case here. We've designed this facility to look at these types of accidents and we've planned on making sure that we continue to protect our employees and we protect the environment. And our system worked as designed."
Still, no one yet knows what caused the first-known radiation release from the massive rooms dug out of the 2,000-foot (610-meter) thick ancient Permian Sea bed. Eventually, they will be covered in concrete, with the intent of safely sealing the casks of mostly solid waste 2,150 feet (655 meters) underground.
But watchdog Don Hancock of the Southwest Research and Information Center says WIPP has now failed in its long-stated mission "to start clean, stay clean."
On Feb. 5, the mine was shut and six workers sent to the hospital for treatment of smoke inhalation after a truck hauling salt caught fire. Nine days later, a radiation alert activated in the area where newly arrived waste was being stored. Preliminary tests show 13 workers suffered some radiation exposure, and monitors as far as half a mile away have since detected elevated levels of plutonium and americium in the air. Ground and water samples are being analyzed.
Officials said they're confident the incidents are unrelated. And while they emphasize that the levels detected off-site are no more harmful than a dental X-ray, they have not been able to go underground, and have not directly answered questions about how contaminated the tunnels might be.
"There's a whole lot of stuff that we don't know," said Hancock. "A lot more sampling that needs to be done."
Explore further: Ukraine begins construction of new nuclear waste storage