The group soon shuffles to follow the same path nuclear waste would. First, to the unloading area, where a container called a TRUPACT, built to protect and seal off its contents if it’s, say, dropped in water, dropped on a spike, or set on fire — is being readied for emplacement. Workers pull the actual waste — drums arrayed on a kind of lazy Susan — up and out of the TRUPACT shell. It twists like a carnival ride before being lowered onto a platform for processing. The radioactivity of this waste is low enough that the drums themselves are thick enough to shield workers.
The site the waste is coming from (national laboratories like Los Alamos, or other Department of Energy facilities where nuclear weapons work takes place) and WIPP workers both do due diligence to characterize what’s inside these drums, and ensure it is properly packaged. Sometimes that involves watching video of the drums being filled, sent by the facility; sometimes it involves X-rays that produce digital images of a drum’s innards; sometimes, it’s lower tech, like jostling a barrel to see if there’s any liquid, as if it were a cup of dwindling soda.
Technicians also measure the radiation from the waste, to ensure it is within the facility’s medium-radioactivity limits. Perhaps most importantly, they take stock of “fissile material,” which decays by splitting into smaller atoms, to ensure that they can’t start a chain reaction, in which fission begets more fission in a self-sustaining cycle that releases significant radiation.
That’s all difficult for what’s called “legacy waste” — radioactive trash created long ago when records were less detailed and methods less stringent than they are now. Some of it was simply put in containers and buried in shallow trenches, or even above-ground, on the nuclear labs’ property during the Cold War. Legacy material makes up much of WIPP’s contents, and much of what will be in its future deliveries.
For more modern material, also coming from Department of Energy sites that work on weapons, WIPP gets involved from the start — “before we even generate the waste,” explained Tammy Hobbes, vice president at Salado Isolation Mining Contractors, the company that operates WIPP on behalf of the Department of Energy’s Environmental Management office. That involves preemptively characterizing it. “We understand everything about it,” said Hobbes of this newer waste. “The process that was used to make it, how it was accumulated, how it was packaged, how it was sorted, how it was stored.”
No matter when or where the waste comes from, technicians, like those the tour group watches, always test for contamination, any potential leaks from its hazardous cargo into the TRUPACT, which should still contain it. If there’s a positive result, the containers are put back in their TRUPACTs, and go back where they came from, carrying an embarrassing report card home.
Those checks and balances have been fine-tuned since 2014, when WIPP experienced its greatest setback.
February that year was a bad month for the plant. First, a truck hauling salt caught fire underground, spreading soot on important equipment and smoke throughout the site — and endangering the 86 workers underground. Everyone made it the 2,000 feet to the surface, but several had to be treated for smoke inhalation.
Just over a week later, in a different part of WIPP, a drum of waste exploded, turning itself essentially into a dirty bomb, blasting out transuranic radioactive material in a fiery burst.
Twenty-two workers received doses of radiation, and a small amount of contamination escaped into the outside world — about 3 percent of the amount of radiation from a chest X-ray.
The dangerous drum had originally come from Los Alamos, where workers had mixed in the wrong kind of cat litter — a simple substance that typically helps stabilize nuclear waste. But in this case, instead of combining the hazardous substances with inorganic kitty litter, they had mixed it with “an organic kitty litter,” the instructions having gotten garbled. And organic material can react with nitrates, causing chemical reactions that release heat. The increasing heat bumped up the pressure inside the drum, until it burst.
“They were clearly being charged with getting as many shipments done as they possibly could, each year,” said Bollinger. When quantity is the goal, quality can suffer.
After the accident came a yearslong shutdown for WIPP, a period that DOE and WIPP officials usually refer to as “the recovery.” When the facility opened back up, its speed slowed. Today, WIPP receives 17 shipments a week — whereas they were managing more than 30 when the accident happened. “They were hustling, and hustling and hustling,” said Bollinger.
Bowen, the Columbia University research scholar, considers the accidents significant in part because after the “recovery,” there was, actually, a recovery: The facility restarted, and there was not a total revolt from the region’s residents.
“That one was kind of surprising, shocking,” he said. “The community and the state felt like it was a breach of trust.” But, he continued, the relationship between the state, its people, and the feds operating WIPP “was strong enough to survive it.” The site’s shutdown also led to material improvements.
In fact, the accident may actually prolong WIPP’s life: For one, it lost almost three years of operations, so it will take longer to fill the allowed volume of waste. And two, the facility received funds to revamp. “You aren’t going to put a lot of money and upgraded systems and then shut it down,” said Don Hancock, director of the nuclear waste safety program at the nonprofit Southwest Research and Information Center, who advocates for limiting the timeline and contents of the facility.
One of those investments, for example, is the nearly $500 million Safety Significant Confinement Ventilation System, an impressive series of tubes that can suck air from the underground and send it through the one of the world’s largest set of HEPA filters, improving air purifying capacity both in everyday and emergency situations. It comes with a new air shaft.
The system, which boasts pipes so big they tower around humans, would also increase the general airflow underground, allowing WIPP workers to mine salt and emplace waste simultaneously, whereas they currently only have enough air to do one or the other. The system is in the final stages of preparation, before it starts operation.
The 2014 accidents may have been the most significant in WIPP’s history, but yearly, smaller incidents also occur. “It’s difficult to operate this kind of facility,” said Hancock. “Nobody in the world has ever safely operated a deep geologic repository.”
And that is the difference between the real world and a report from a national academy about what kind of rock or mineral is safe: A place can be perfect in geological theory, but when operated by flawed humans, it will be subject to their mishaps and misjudgments.
Perhaps that is part of why humans have had such a hard time agreeing about where to construct other deep geological repositories, and how to go about building them. Congress, for instance, mandated a facility for high-level waste in Nevada, called Yucca Mountain. After years of work and billions of dollars spent, the project was canceled in 2010. Before WIPP, officials considered an abandoned salt mine in Kansas for a pilot site, but they faced both state opposition and oil and gas wells they hadn’t known about nearby.
Abroad, other countries are making progress on deep underground repositories: In Finland, a permanent facility called Onkalo will soon come online, housing spent nuclear fuel. Sweden, meanwhile, expects to begin operating its Forsmark facility in the 2030s. Canada has narrowed its potential sites to two areas that proactively expressed interest in hosting. In all three cases, having the communities on board has been key to a smooth, if still lengthy, process.
On the tour, the group heads into the underground area where some of these incidents took place. They shuffle to the mine office, where each person is given a brass coin with a unique number. It’s like a dogtag, the administrator explained: If there were a fire, the coin wouldn’t burn. But they would be able to identify the humans who had.
That somber and vivid thought in mind, the group enters the open-cage elevator — which people here like to call “the conveyance” — to descend foot by foot into increasing darkness, the walls of the shaft first lined with metal, then showing their true nature: just salt.
At the bottom, the floor looks like a white-sand beach; the air is hazy with tiny crystals that stick to skin, leaving lips tasting like the ocean. A break area for employees consists of a salty room with salty chairs, salty picnic tables, and salty cargo containers outfitted with refrigerators and microwaves. Visitors can pluck (radioactively safe) salt from the ground and take it home in a WIPP-branded Ziploc.
“Welcome to the WIPP underground,” a sign proclaims. “You have just entered an environment committed to safety.”
Above, giant bolts poke from the ceiling and extend deep into the salt, helping hold it up by transferring some of the load farther into the material. The salt is constantly shifting, creeping, wanting to fall.
That’s good for the future: When WIPP is full, and operations shut down, that crackle and pop will seal waste off from the surface, thousands of feet above. But it’s worrisome when people are still working down here, among unnerving cracks and buckles in the walls. A 2014 National Academy of Engineering report noted that this creep makes salt “poorly suited for keeping the cavity open for monitoring and retrievability.”
The salt’s geologic movements are the primary concern in the near-term, and so they are monitored, pointing engineers to where they should place the bolstering bolts where they’re necessary for stability. Sometimes, though, not well enough: Since 2014, there have been several collapses. One happened near the area of the accident, which, since it was designated dangerous to workers, hasn’t seen the intended maintenance, contaminated as it was. In whatever nuclear waste repositories populate the future, figuring out how to keep them stable — perhaps for much longer than is required of WIPP — will be important.
That coiled threat above the tour group’s heads, the officials creep in electric carts. They head toward an area where technicians are currently emplacing waste, where drums of nuclear waste are stacked three-high and honeycombed from front to back. The group, disembarking the cart, march toward this battalion of barrels, accompanied by a radiological control technician who keeps watch on their doses.
If all goes as planned, the group is looking at where this waste will live forever, salt eventually crashing down on top of it. The infrastructure above will be dismantled, the entrances sealed, and signage placed atop warning would-be visitors for the next 10,000 years to stay away.