LONDON – An article in the scientific journal Nature warns the U.S. government about the long-term risks of burying 34 tons of plutonium waste from nuclear weapons in a pit more than 600 meters (1,970 feet) deep in Carlsbad, New Mexico.
The U.S. Department of Energy expects to permanently consign that material to its Waste Isolation Pilot Plant, or WIPP, in Carlsbad, currently the world’s only facility of its kind.
Hundreds of thousands of plastic-lined steel drums are already stacked at the bottom of the WIPP, which was carved out of rock down to the level of a salt basin formed approximately 250 million years ago.
The storage facility is half-full already and is to be permanently sealed in 2033, leaving the plutonium-239, which has a radioactive half-life of more than 24,000 years, encapsulated for millennia.
The U.S. originally planned to reprocess military nuclear waste into fuel for nuclear power plants, but the skyrocketing projections of the costs of reprocessing led the DOE to consider an alternative.
The scientists who wrote the Nature article, led by Stanford University’s Rodney Ewing, said the DOE has not taken into account some long-term risks to storing plutonium in the WIPP, such as unexpected chemical reactions.
Under international agreements, the U.S. has a responsibility to guarantee the safety of the facility for at least 10,000 years.
But according to Ewing and his colleagues, a February 2014 incident in Carlsbad calls into question the ability of U.S. officials to meet that obligation.
An element in the nuclear waste reacted in an unexpected way with the materials in the drum containing it, resulting in a leak of radioactive gas that spread through the ventilation system and exposed 21 employees to low levels of radioactivity.
The scientists writing in Nature said that while the February 2014 episode did not lead to serious consequences, it illustrates the difficulty in predicting potential failures in a facility that is meant to function for thousands of years.
“The DOE has aggressively identified its causes and implemented corrective actions; incompatible chemicals are no longer mixed in the drums. But once the repository is closed, its contents cannot be monitored or problems fixed,” the authors said.
As posted in the Latin American Herald Tribune, Friday, January 15, 2016 at http://www.laht.com/article.asp?ArticleId=2403529&CategoryId=36641