A drum of radioactive waste exploded in New Mexico last year due to workers mixing in the wrong type of kitty litter, according to a new report from the U.S. Department of Energy. The offending drum, packed at Los Alamos National Laboratory (LANL) and sent to the Waste Isolation Pilot Plant (WIPP) near Carlsbad, burst after the organic kitty litter Shweat Scoop was used instead of the usual clay-based kitty litter.
Kitty litter is regularly used to stabilize radioactive material for packing. The report concluded that the contents of the drum were "chemically incompatible" and the explosion was a result of internal reactions that generated more heat and gases than the drum could vent.
The explosion, which resulted in an estimated $240 million of clean up and recovery, happened underground on February 14, 2014. The Santa Fe New Mexican concluded after its own a six-month investigation that the organic kitty litter mistake resulted from a typo in the LANL policy manual. The WIPP, filled with underground waste rooms carved out of a 250-million-year-old salt formation, is the only federal repository for the U.S.'s transuranic waste (material containing artificially made, radioactive elements).