The New Mexico Environment Department says Los Alamos National Laboratory packed 57 containers of nuclear waste with a type of kitty litter thought to have caused a radiation leak at the federal government's troubled repository.
Department Secretary Ryan Flynn on Monday gave the lab two days to submit a plan for fixing the problem, saying the barrels may "present an imminent and substantial threat" to public health and the environment.
He says the barrels were packed with nitrate salts and organic kitty litter, a combination thought to have caused a heat reaction and radiation release. The litter soaks up any liquid before drums of waste are sealed and shipped to the Waste Isolation Pilot Plant.
Only two of those containers are thought to be at WIPP, meaning the rest are stored at the lab or at a temporary site in west Texas.
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