The Salt Mine Solution

In the Salado salt formation a half-mile below the New Mexico desert, WIPP has room to store all the radioactive waste an expanded nuclear power program could produce. Emphasis on the word could.
Publish date:
Social count:
In the Salado salt formation a half-mile below the New Mexico desert, WIPP has room to store all the radioactive waste an expanded nuclear power program could produce. Emphasis on the word could.

The "nice" elevator is right out of a luxury hotel with a smooth ride and room for 75 people. It has six degrees of safety redundancy, which means that if one cable were to snap, several others, plus an emergency brake or two, would prevent the six of us from hurtling to our deaths. But just as I'm adjusting the self-rescuer respirator on my utility belt, we get the news: There's a problem with the "nice" elevator. We have to take the salt shaft.

The "other" elevator is really a glorified cage pulled along a single cable through a vertical salt shaft; it has one level of redundancy and clatters up and down the shaft like an old roller coaster. "You're going to feel the floor drop from under you," says our tour leader, Roger Nelson, as the cage doors rattle closed and the elevator begins a creaky, 2,150-foot descent. Within seconds, everything goes pitch black. Nelson mentions that now would be a good time to focus the lamps in our miner's helmets, and a few switch on, small points of light playing off shaft walls that are speeding past outside the cage. "Everybody's gotten real quiet," Nelson says, as the air grows cool. "Praying?"


After five minutes that feel like 20, the ride ends and we step out of the cage into a long corridor with gray walls, shot through with red streaks. The first sign we see says: "Welcome to the WIPP Underground. You have just entered an environment committed to SAFETY." The next sign we see says: "STOP! If it's not safe, don't do it."

There are reasons for the warnings. Here, a half-mile below the southern New Mexico desert, we are entering the only operating deep geologic nuclear waste disposal site in the world. The Department of Energy's Waste Isolation Pilot Plant has been disposing of nuclear waste since 1999; its trucks have logged more than 7 million miles across the United States, bringing both low- and high-grade radioactive waste to the facility. In its decade of operation, WIPP has disposed of 95,000 loaded waste containers, the equivalent of 250,000 55-gallon drums, with no toxic releases to the environment or contaminated personnel. Although WIPP has received startlingly little media attention in light of the Obama administration's decision to abandon plans to store waste in Nevada's Yucca Mountain, experts say the facility and its surrounding area have the capacity to store all of the nuclear waste humans could create in the next 10,000 years.

Unfortunately, there's a bureaucratic hitch: Under President Carter, the United States decided in 1977 not to reprocess spent nuclear fuel from commercial power plants to create plutonium and other fissile materials that could fuel more power plants. But the government ruled that spent fuel rods should be stored in a way that would allow them to be retrieved for reprocessing.

So the U.S. divided nuclear waste into two general groups: Commercial waste from power plants was to go to the Yucca Mountain disposal site in Nevada, from which it could be extracted if necessary; and defense waste, collected from military sites and naval yards around the country, was consigned to WIPP. But now, after decades of political and technical controversy, it seems likely Yucca Mountain will never be finished. And even though WIPP — located within the Salado salt formation, a massive bedded salt deposit so tight that 230-million-year-old sea water from the Permian Age can still be seen, trapped within its crystals — is storing waste exactly as planned, it still cannot be used for the spent fuel America's commercial nuclear power plants produce.

The virtues of the Salado formation are legion: The salt emits almost none of its own radiation, and a half-mile deep in the earth, the deposit is well-isolated, but soft and easy to mine. Also, the salt is "plastic," moving a few inches per year, creeping into WIPP's caverns of nuclear waste to eventually seal them. Once the salt walls close in around the barrels and drums, fractures and openings will shut, leaving no pathway for water or waste to get in or out.

In 15 years, the DOE estimates, the underground facility will be completely closed and impermeable for tens of thousands of years.

Everything you're looking at is salt," says Jim Conca, who is no sooner out of the elevator cage than he's kneeling by a wall with a pick-axe in hand, prying loose a crystalline chunk of 225-million-year-old, 99-percent-pure salt. "This is the stuff that's great for margaritas." Eager and affable and sporting a small earring, Conca is the director of New Mexico State University's Carlsbad Environmental Monitoring and Research Center, which has the lowest radiochemical detection limits of any facility in the world and, for the past 13 years, has been checking the air, water, soil and people in a 100-mile radius around WIPP. "Working here," he says, citing WIPP's spotless record, "is safer than working at Toys R Us."

The chief scientist at WIPP, Nelson, is more circumspect than the exuberant Conca, but he still grins and sticks out his thumb as we wait for a jeep to arrive. Once behind the wheel, Nelson explains that the mine — named New Mexico's safest for 21 straight years — has everything its workers need underground: vehicle maintenance shops, lunch rooms (or "dinner holes," as the miners call them), even dedicated ambulance and fire services. In a series of small alcoves dug into the salt walls of the main hallway sit vintage ambulances and fire trucks, still fully operational, their miniature frames perfectly suited to squeeze through the narrow tunnels and one-way traffic of the salt mine.

WIPP's mile-wide underground area includes a series of corridors that occasionally meet at cavernous intersections; whenever Nelson reaches a crossroads, he slows and gives several quick bursts of the horn as a warning to other vehicles. The dusty floors are littered with discarded ear plugs; danger signs and emergency telephones dot the jagged walls, which have occasional strips of red where ancient dirt is trapped in the salt. Many of the hallways are separated by airlocks, with swinging doors that whoosh open and closed to prevent the air from adjacent rooms mixing. The airtight doors are controlled by green and red cords that dangle from the ceilings and are easy to reach from a vehicle: Red closes the door behind; green opens the one in front. "Even us federal employees can figure that out," Nelson cracks.


Controlled air flows through the underground facility from one end to the other, monitored continuously by a variety of sensors until it exits through an exhaust shaft, never to re-circulate in the mine. The temperature drops the farther we progress, and as I run my tongue over my lips, which have cracked in the mine's 1 percent humidity, all I taste is salt. "When we turn the corner," Nelson's voice echoes in the deep, "you'll see the nuclear legacy of the Cold War over the past 60 years between the East and the West."

Around the bend is a 100-yard-deep cavern, about 10 yards wide and 5 yards tall, filled to its outer edge and ceiling with black barrels, all bearing the telltale yellow hazard symbol for radioactivity. The barrels, three layers high and six columns wide, are taped together in groups of five, and 10,000 drums can fit in each hangar. When fully excavated, WIPP will consist of nearly 60 such hangars. "We probably shouldn't go any closer," says Nelson when our group is about 20 feet away from the barrels. "They don't have the RadRope up to block it off." I sneak a glance at the dosimeter clipped to my lapel, and sure enough, it shows no radioactive reading. The heavily insulated drums before me are all filled with transuranic waste (meaning the waste contains elements above uranium on the periodic table, mainly plutonium); much of the material inside the gigantic drums and barrels is contaminated detritus like chair legs, rags or rusted tools. "There's so much robustness in this design, it's unbelievable," Nelson says. "This looks like everyone's concept of high-level disposal." In fact, government officials from France recently went "down hole" to examine WIPP.

We clamber back into the jeep and drive headlong into the intake air, a fierce wind in our faces, past empty caverns still awaiting their first shipments of waste. And they could be waiting a while: Although the United States generates 20 percent of its power from nuclear sources, only 2,000 tons of nuclear waste are generated each year, about half a railroad car's worth. (As Conca points out, coal-burning power plants actually produce more radioactive waste each year).

Back above ground, Nelson shows us the Hot Cell, a room specially designed to handle highly radioactive waste before it is sent, by underground railroad, into the salt mine; he notes with an air of disappointment that it could be dealing with materials 100 times more radioactive, if not for decades-old Environmental Protection Agency regulations. It's guarded by a 4-foot-thick orange door, which takes an hour to open or close, prompting Conca to observe: "Everything's so wonderfully brute-force around here." There's another purpose to the Hot Cell, however: Because the operators of WIPP are required to assume there will be future human interest (or even intrusion) in the site, the Hot Cell will remain standing long after the mine is closed and the rest of the facility's above-ground buildings have been torn down. The DOE consulted with panels of linguists, anthropologists and other scientists while studying potential intrusion scenarios, and hieroglyphics, geometric symbols and writing in seven languages will cover the exterior of the Hot Cell and surrounding monuments, explaining to visitors thousands of years in the future why the salt deposits thousands of feet below should not be disturbed.

Conca, who in previous decades worked both on NASA's doomed Challenger program and the now-sidelined Yucca Mountain project (which he calls "unnecessary ... and a bad place to put it"), is adamant that WIPP represents the United States' best —and perhaps last — chance to seize the reins of the world's energy crisis. He spent the first part of 2009 pitching Obama administration officials in the State Department, along with policymakers at Berkeley and Lawrence Livermore Labs in California, on the promise of nuclear energy. It is so much safer than coal, he stresses, and so much more efficient than the myriad green technologies that are still decades away from having a real impact on the world's energy markets. In Conca's mind, WIPP counters many of the objections to nuclear power: Proliferation becomes a nonissue if the United States would agree to store other countries' waste ("and we wouldn't even notice it," Conca says), and costs would significantly decrease as new generations of reactors are built. In a world where 2.5 billion people still burn wood or manure as their primary sources of energy, Conca's calculations tell him that a switch to nuclear power is not only necessary but the only safe and ethical path to pursue.

"This," says Conca, waving his arm toward the cluster of nondescript beige buildings in the gusty New Mexico desert that are WIPP, "is the best thing we can do. Nuclear waste disposal should not be the hurdle that keeps nuclear power from getting to the levels we need. The alternatives would be devastating economically and environmentally." He sighs.
"You can make it an issue if you want to, but it's all political."

Western Civ checks in on intellectual life and policy solutions in the far American reaches west of the Hudson and Potomac. E-mail: