Use of Wrong Kitty Litter Blamed for Accident at Nuclear Waste Dump

Posted on March 27, 2015

There was an accident last year at The U.S. Department of Energy's (DOE) Waste Isolation Pilot Plant (WIPP). The plant was forced to close after accident. WIPP is described as the only deep geologic repository for nuclear waste in the U.S. It is located in southeast New Mexico. Drums of nuclear waste, also known as TRU waste, is deposited in the underground repository, which was carved out of a 2,000-foot-thick salt bed.

TRU waste is contained in drums at the site. In the incident last year a drum of nuclear waste burst open and leaked. A Technical Assessment Team (TAT) evaluated the mechanisms and chemical reactions contributing to the failure. In its report, the TAT concluded that one waiste drum, Drum 68660, was the source of radioactive contamination released during the February 14, 2014, radiological event.

The report, which can be found online here, says Swheat Scoop kitty litter was used on the waste in drum 68660.

Using Swheat Scoop brand kitty litter on the nuclear waste was not right. NPR reports that the study found that wrong kitty litter was used in the damaged drum. Kitty litter helps soak up some liquid nuclear waste just like it helps soak up kitty waste but the organic compounds in the litter triggered a chemical reaction. Swheat Scoop is an organic kitty litter and only inorganic kitty litter is supposed to be in the nuclear waste drums at WIPP.

The Swheat Scoop kitty litter brand is mentioned 399 times in the report. The report says, "Swheat Scoop layers may have formed a localized region of reactivity leading to the thermalrunaway event." It also says, "The analytical evidence supports the conclusion that an exothermic oxidation reaction of Swheat Scoop by metal nitrate salts produced gases that contributed to the breach of Drum 68660."

The researchers also conducted experiments that found that various combinations of nitrate salt, Swheat Scoop, nitric acid, and oxalate self-heat at temperatures below 100°C.

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