CARLSBAD, Calif., March 27 (UPI) -- A radiation leak that contaminated 21 workers at the nation's only underground nuclear waste dump in New Mexico was caused by cat litter, the U.S. Department of Energy found.
Investigators said a single 55-gallon drum of nuclear waste shipped before February 2014 to the Waste Isolation Pilot Plant contained an organic form of cat litter instead of the non-organic kind that is usually used.
The ensuing chemical reaction caused a buildup of gases inside the sealed drum and subsequent explosion. Cat litter is used to absorb liquids inside the barrels.
"A series of ever-increasing heat releasing reactions occurred, which led to the creation of gases within the drum," the Energy Department wrote. "The resulting build-up of gases within the drum displaced the drum lid, venting radioactive material and hot matter that further reacted with the air or other materials outside the drum to cause the observed damage ..."
The report said the barrel came from the Los Alamos National Laboratory, also in New Mexico. It contained Swheat Scoop, branded as natural, which had never been used before in the nuclear lab. It took about 70 days from the time the barrel was packaged to the explosion.
