A Department of Energy nuclear lab used the wrong kind of kitty litter in its haste to dispose of hazardous waste last year, leading to a radiation leak that sickened at least 20 workers and caused a shutdown of a federal disposal plant to the tune of $500 million.

The report from the Santa Fe New Mexican characterizes the Los Alamos National Laboratory (LANL) in New Mexico and its private operator, Los Alamos National Security LLC, as being so careless with the hazardous material that they inadvertently created what one chemist called a potential bomb. The LANL is a federal laboratory that works on nuclear technology and other national security projects.

“This action may have led to an adverse chemical reaction within the drums resulting in serious safety implications,” the Department of Energy’s Office of Inspector General said in an October report, according to the newspaper.

The Santa Fe New Mexican published the report after a six-month long investigation that included interviews and thousands of documents obtained through a Freedom of Information Act request.

According to the newspaper, the LANL took shortcuts when prepping a highly acidic batch of nuclear waste for disposal at the Waste Isolation Pilot Plant, an underground disposal plant for nuclear waste that is also in New Mexico. The lab was working vigorously to meet a June 30, 2014 deadline for disposal of Cold War-era waste that would help Los Alamos National Security LLC secure a renewed contract with the Energy Department.

In its haste, according to the Santa Fe New Mexican, the lab used a “wheat-based kitty litter rather than clay-based kitty litter” to absorb some of the material. This mistake turned the waste into a mixture that was “akin to plastic explosives,” the paper reported.

The mistake was small, but costly. The Santa Fe New Mexican reported that in February 2014, once the drum containing waste had reached the Waste Isolation Pilot Plant, it cracked open. At least 20 workers at the plant were injured by low levels of the radiation and the plant was shut down.

According to the newspaper, the LANL downplayed the dangers of the contents of the drum to the plant but internally investigated why the kitty litter had been switched. They eventually concluded it was the result of a simple mistake: a typo in a policy manual.

A spokesperson for the LANL said they had no comment in response to the Santa Fe New Mexican report.

The executive director of a watchdog group that investigates the LANL told the Santa Fe New Mexican that the lab should have realized they were sending a dangerous mixture to the plant.

“It took only seconds with Google to find explosives’ patents when the foremost ingredients in Waste Drum 68660 were punched in,” Greg Mello, executive director of the Los Alamos Study Group, said.

Mello told KOB that it is clear that “corners were cut” at the laboratory, and the culture needs to change.

"If management does not change, there will be a worse accident," he said.

The Santa Fe New Mexican reported that four managers have been replaced at the lab since the incident, but it was unclear what if any impact the incident would have on Los Alamos National Security LLC’s contract with the government.

Meanwhile, the newspaper reports, the Waste Isolation Pilot Plant remains closed. Federal officials have estimated it may take years to reopen the plant and will cost at least $500 million.

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