Gala had been this deep in the cave once before, in 2009, but never beyond the pool. A baby-faced Pole of unremarkable physique—more plumber than mountaineer—he discovered caving as a young man in the Tatra Mountains, when they were one of the few places he could escape the strictures of communism. When he was 17, he and another caver became the first people to climb, from top to bottom, what was then the world’s deepest cave, the Réseau Jean Bernard, in the French Alps. Now 38, he had explored caves throughout Europe and Ukraine, Hawaii, Central America, and New Guinea. In the off season, he was a technician on a Norwegian oil platform, dangling high above the North Sea to weld joints and replace rivets. He was not easily unnerved. Then again, Chevé was more than usually unnerving.
Caves are like living organisms, James Tabor wrote in Blind Descent, a book on Bill Stone’s earlier expeditions. They have bloodstreams and respiratory systems, infections and infestations. They take in organic matter and digest it, flushing it slowly through their systems. Chevé feels more alive than most. Its tunnels lie along an uneasy fault line in the Sierra de Juárez mountains and seethe with more than seven feet of rain a year. On his first trip to Mexico, in 2001, Gala nearly died of histoplasmosis, a fungal infection acquired from the bat guano that lined the upper reaches of a nearby cave. The local villagers had learned to steer clear of such places. They told stories of a malignant spirit that wandered Chevé’s tunnels, its feet pointing backward as it walked. When Western cavers first discovered the system, in 1986, they found some delicate white bones beneath a stone slab near the entrance: the remains of children probably sacrificed there hundreds of years ago by the Cuicatec people.
When the call to base camp was over, Gala hiked to the edge of the pool with his partner, the British cave diver Phil Short, and they put on their scuba rebreathers, masks, and fins. They’d spent the past two days on a platform suspended above another sump, rebuilding their gear. Many of the parts had been cracked or contaminated on the way down, so the two men took their time, cleaning each piece and cannibalizing components from an extra kit, knowing that they’d soon have no time to spare. The water here was between 50 and 60 degrees—cold enough to chill you within minutes—and Gala had no idea where the pool would lead. It might offer swift passage to the next shaft or lead into an endless, mud-dimmed labyrinth.
The rebreathers were good for four hours underwater, longer in a pinch. They removed carbon dioxide from a diver’s breath by passing it through canisters of soda lime, then recirculating it back to the mouthpiece with a fresh puff of oxygen. Gala and Short were expert at managing dive time, but in the background another clock was always ticking. The team had arrived in February, three months before the rainy season. It was only mid-March now, but the weather wasn’t always predictable. In 2009 a flash flood had trapped two of Gala’s teammates in these tunnels for five days, unsure if the water would ever recede.
Gala had seen traces of its passage on the way down: old ropes shredded to fiber, phone lines stripped of insulation. When the heavy rain began to fall, it would flood this cave completely, trickling down from all over the mountain, gathering in ever-widening branches, dislodging boulders and carving new tunnels till it poured from the mountain into the Santo Domingo River. “You don’t want to be there when that happens,” Stone said. “There is no rescue, period.” To climb straight back to the surface, without stopping to rig ropes and phone wire, would take them four days. It took three days to get back from the moon.
The truth is they had nowhere better to go. All the pleasant places had already been found. The sunlit glades and secluded coves, phosphorescent lagoons and susurrating groves had been mapped and surveyed, extolled in guidebooks, and posted with Latin names. To find something truly new on the planet, something no human had ever seen, you had to go deep underground or underwater. They were doing both.
Caving is both the oldest of pastimes and the most uncertain. It’s a game played in the dark on an invisible field. Until climbing gear was developed, in the late 19th century, a steep shaft could end an expedition, as could a flooded tunnel—cavers call them terminal sumps. If an entrance wasn’t too small or a tunnel too tight, the cave could be too deep to be searched by torch or candlelight. In the classic French caving books of the 1930s and ’40s, Ten Years Under the Earth, by Norbert Casteret, and Subterranean Climbers, by Pierre Chevalier, the expeditions are framed as manly jaunts belowground—a bit of stiff exercise before the lapin chasseur back at the inn. The men wear oilskins and duck-cloth trousers, carry rucksacks and rope ladders, and light their way with a horse-carriage lantern. At one point in Subterranean Climbers, a sweet scent of Chartreuse fills the air and the party realizes, with dismay, that their digestif has come to grief against a fissure wall. Later a rock tumbles loose from a shaft and conks a caver named François on the head, causing some discomfort. The victim, Chevalier notes with regret, was “poorly protected by just an ordinary beret.”
Chevalier and his team went on to map more than 10 miles of caverns in the Dent de Crolles, outside Grenoble. Along the way they set the world depth record—2,159 feet—and developed a number of caving tools still used today, including nylon ropes and mechanical ascenders. Casteret may have done even more to transform the sport. In the summer of 1922 he was hiking in the French Pyrenees when he noticed a small stream flowing from the base of a mountain. He shucked off his clothes and lit a candle, then wedged himself through the crack and waded in. The tunnel followed the stream for a couple of hundred feet, then dipped below the waterline. Rather than turn back, Casteret set his candle on a ledge, took a deep breath, and swam ahead, groping the wall till he felt the ceiling open up above him. He went on to explore many miles of tunnels inside the cave, culminating in a pair of large, airy galleries. The first was covered in spectacular limestone formations. The second was smaller and drier, with a dirt floor. When Casteret held his candle up to its walls, the flame flickered over engravings of mammoths, bison, hyenas, and other prehistoric beasts—the remains of a religious sanctuary some 20,000 years old.
Casteret and Chevalier helped turn caving into a heroic undertaking and the search for the world’s deepest cave into an international competition—a precursor to the space race. “Praise Heaven, no one can give France lessons in this matter of epic achievement,” Casteret wrote in his preface to Chevalier’s book. “The race of explorers and adventure-seekers has not died out from our land.” By combining lighter, stronger climbing gear with scuba tanks, cavers went deeper and deeper into the earth, more than tripling Chevalier’s depth in the next 60 years. The record would bounce between France, Spain, and Austria (where one of Gala’s teams went below 5,300 feet at Lamprechtsofen in 1998) before settling in the Republic of Georgia in 2004.
A cave’s depth is measured from the entrance down, no matter how high it is above sea level. When prospecting for deep systems, cavers start in mountains with thick layers of limestone deposited by ancient seas. Then they look for evidence of underground streams and for sinkholes—sometimes many miles square—where rain and runoff get funneled into the rock. As the water seeps in, carbon dioxide that it has picked up from the soil and the atmosphere dissolves the calcium carbonate in the stone, bubbling through it like water through a sponge. In Georgia’s Krubera Cave, in the Western Caucasus, great chimneylike shafts plunge as much as 500 feet at a time, with crawl spaces and flooded tunnels between them. The current depth record was set there in 2012, when a Ukrainian caver named Gennadiy Samokhin descended more than 7,200 feet from the entrance—close to a mile and a half underground.
The Chevé system is even deeper. Drop some fluorescent dye into the stream at the entrance, as a teammate of Stone’s did in 1990, and it will tumble into the Santo Domingo eight days later, 11 miles away and 8,500 feet below. No other cave in the world has such proven depth (though geologists suspect that some caves in China, New Guinea, and Turkey go even deeper). But that isn’t enough to set a record: cave depths, unlike mountain heights, are inherently subj
ective. Everest was the world’s tallest peak long before Edmund Hillary and Tenzing Norgay scaled it. But a cave is only officially a cave when people have passed through it. Until then it’s just another hole in the ground.
Deep caves rarely call attention to themselves. Like speakeasies and opium dens, they tend to hide behind shabby entrances. A muddy rift will widen into a shaft, a crawl space into a vaulting nave. Krubera begins as a grave-size hole full of moss and crows’ nests. When local cavers first explored it, in 1960, they got less than 300 feet down before the shaft leveled off into an impassable squeeze. It was more than 20 years before the passage was dug out, and another 17 before a side passage revealed the vast cave system beneath it. Yet the signs were there all along. The bigger the cave, the more air goes through it, and Krubera was like a wind tunnel in places. “If it blows, it goes,” cavers say.
Chevé has what cavers call a Hollywood entrance: a gaping maw in the face of a cliff, like King Kong’s lair on Skull Island. A long golden meadow leads up to it, bordered by rows of pines and a stream that murmurs in from the right. It feels ceremonial somehow, like the approach to an altar. As you walk beneath the overhang, the temperature drops, and a musty, fungal scent drifts up from the cave’s throat, where the children’s bones were found. The stream passes between piles of rubble and boulders, their shadows thrown into looming relief by your headlamp. Then the walls close in and the wind begins to rise. It’s easy to see why the Cuicatec felt that some dark presence abided here—that something in this place needed to be appeased.
Like Krubera, Chevé starts with a precipitous drop: 3,000 feet in less than half a mile. But then it levels off to a more gradual slope: to go another vertical mile, you have to go 10 miles horizontally, at least half a mile of it underwater. Although the water eventually gathers into a single stream, the cave’s upper reaches are full of oxbows and tributaries, meandering and intertwining through the rock, paralleling one another for a stretch, then veering apart or abruptly ending. It’s tempting to imagine the system as a giant Habitrail, with cavers scurrying through it. But these tunnels weren’t meant for inhabitants. They’re geological formations, differentially eroded, their soft deposits ground down to serrated edges or carved into knobs and spikes that the body has to contort itself around. A long squirm down a tight shaft will lead to an even longer crawl, a slippery descent, and so on, in a natural obstacle course, relentless in its challenges. Near the main entrance there’s a 30-foot section known as the Cat Walk, where a caver can hoist his pack and stroll forward without thinking. It’s the only place like it in the system. “Every other piece of this cave might kill you,” Gala told me.
Bill Stone has led seven expeditions to Chevé in the past 10 years, all but one of them with Gala. In 2003 his team dove through a sump that had thwarted cavers for more than a decade, then climbed down to nearly 5,000 feet, making Chevé the deepest cave in the Western Hemisphere. But there was no clear way forward: the main passage ended in a wall of boulders. The only option was to try to bypass the blockage by entering the system farther downslope. The following spring Stone sent teams of Polish, Spanish, Australian, and American cavers bushwhacking across the cloud forest in search of new entrances. They found more than 100, including a spectacular cliff-face opening called Atanasio. The most promising, though, was a more modest but gusty opening labeled J2 (the J was for jaskinia, Polish for “cave”). It was wide open at the top but pinched tight as soon as you went down. The Australians called it Barbie.
The J2 system runs roughly parallel to the main Chevé passage and about 1,000 feet above it. The water’s exact course through the mountain is hard to predict, but cave surveys and Stone’s 3-D models suggest that the two systems eventually merge. If Gala and Short could get past the sump beyond Camp Four, their route should join up with Chevé, drop another 2,500 feet, and barrel down to the Santo Domingo. “Imagine a storm-tunnel system in a city,” Stone told me. “All these feeders connect to a trunk and then go out to an estuary. We’re in the back door trying to get into that primary conduit.” This is it, he said. This is the big one. “If everything goes well, we’ll be as far as anyone has ever been inside the earth.”
Deep caving demands what Stone calls siege logistics. It’s not so much a matter of conquering a cave as outlasting it. Just to set up base camp in Mexico, his team had to move six truckloads of material more than 1,200 miles and up a mountain. Then the real work began. Exploring Chevé is like drilling a very deep hole. It can’t be done in one pass. You have to go down a certain distance, return to the surface, then drill down a little farther, over and over, until you can go no deeper. While one group is recovering on the surface, the other is shuttling provisions farther into the cave. Stone’s team had to establish four camps underground, each about a day’s hike apart. Latrines had to be dug, ropes rigged, supplies consumed, and refuse carried back to the surface. Divers like Gala and Short were just advance scouts for the mud-spattered army behind them, lugging 30-pound rubber duffel bags through the cave—Sherpas of a sort, though they’d never set foot on a mountaintop. Stone called them mules.
Two months earlier, in Texas, I’d watched the final preparations for the trip. Stone’s headquarters are about 15 minutes southeast of Austin, on 30 acres of drought-stricken scrub. There is a corrugated building out front that’s home to Stone Aerospace, a robotics firm he started in 1998, and a two-story log house in back, where he lives with his wife, Vickie, a fellow caver. (They met at a party where Stone overheard her talking about tactical rigging.) The trucks were scheduled to leave in two days, and every corner of the house had been requisitioned for supplies. One room was piled with cook pots, cable ladders, nylon line, and long underwear. Another had dry suits, diving masks, rebreathers, and oxygen bottles. In the basement, eight long picnic tables were stacked with more than 1,000 pounds of provisions. Shrink-wrapped flats of peanuts, cashews, and energy bars sat next to rows of four-liter bottles filled with staples and dry mixes: quinoa, oatmeal, whey protein, mangoes, powdered potatoes, and broccoli-cheese soup. Stone had tamped in some of the ingredients using an ax handle.
“In the past I’d lose twenty-five pounds on one of these trips,” Stone told me. “We can burn as many calories as a Tour de France rider every day underground.” Ascending Chevé, he once said, was like climbing Yosemite’s El Capitan at night through a freezing waterfall. To fine-tune the team’s diet, he’d modeled it on Lance Armstrong’s program, aiming for a ratio of 17 percent protein, 16 percent fat, and 67 percent carbohydrates. In Mexico the supplies would be replenished with local beans, vegetables, and dried machaca beef. “What you aren’t going to find is candy,” Stone said. “Stuff like Snickers—that’s bullshit.” When I looked closer, though, I found a bottle of miniature chocolates that Vickie had hidden among the supplies.
Cavers, even more than climbers, have to travel light and tight. Bulky packs are a torture to get through narrow fissures, and every ounce is extracted tenfold in sweat. Over the years caving gear has undergone a brutal Darwinian selection, lopping off redundant parts and vestigial limbs. Toothbrushes have lost their handles, forks a tine or two, packs their adjustable straps. Underwear is worn for weeks on end, the bacteria kept back by antibiotic silver and copper threads. Simple items are often best: Nalgene bottles, waterproof and unbreakable, have replaced all manner of fancier containers; cavers even stuff their sleeping bags into them. Yet the biggest weight savings have come from more sophisticated gear. Stone has a PhD in structural engineering from the University of Texas and spent 24 years at the National Institute of Standards and Technology, in Gaithersburg, Maryland. His company has worked on numerous robotics projects for NASA, including autonomous submarines destined for Europa, Jupiter’s sixth moon. The rebreathers for the Chevé trip were of his own design. Their carbon-fiber tanks weighed a fourth of what conventional tanks weigh and lasted more than four times longer underwater; their software could precisely regulate the mix and flow of gases.
Stone’
s newest obsession was a set of methanol fuel cells from a company called SFC Energy. Headlamps, phones, scuba computers, and hammer drills (used to drive rope anchors into the rock) all use lithium batteries that have to be recharged. On this trip the cavers would also be carrying GoPro video cameras for a documentary that would be shown on the Discovery Channel. In the past Stone had tried installing a paddle wheel underground to generate electricity from the stream flow, with fairly feeble results. But a single bottle of methanol and four fuel cells, each about the size of a large toaster, could power the whole expedition. The question was whether they’d survive. High-tech gear tends to be fragile and finicky. While I was in Texas, one of the rebreathers kept shutting down for no apparent reason (it was later found to have a faulty fail-safe program), and this was the sixth generation of that design. The fuel cells weren’t nearly as robust. Stone would keep them in shockproof, watertight cases, but he doubted that would suffice. “We’re going to take them down there and turn them into broken pieces of plastic,” he said.
Stone knew what it meant to be a battered piece of hardware: he’d turned 60 that December and had spent more than a year of his life underground. His gangly frame—six feet four, with a wingspan nearly as wide—was kept knotty by free weights, and he could still outclimb and outcarry most 25-year-olds. But he was getting old for an extreme sport like this, and he knew it. He had the whiskered, weather-beaten look of an old lobsterman. “I think it’s a little surprising to him how hard the caving is on his body these days,” one of the team members told me. “I won’t say that he’s feeling his age, but he’s realizing that he isn’t at the pointy end of the stick anymore.”
The Best American Science and Nature Writing 2015 Page 4