Mammoth Cave secrets still being uncovered

MAMMOTH CAVE, Ky. – Gripping a rocky ledge deep underground, Rick Toomey lowered himself gingerly down a 12-foot drop-off in Mammoth Cave, his headlamp flashing past rock walls dotted with sparkling gypsum in a remote section off-limits to tourists and recreational cavers.

A geologist who oversees scientific research at Mammoth Cave, Toomey and two other surveyors rested briefly before dropping to their bellies to crawl hundreds of yards through a narrow passage, their packs and helmets scraping under a rock ceiling barely two feet high.

After three hours in the 54-degree subterranean darkness, the dirt-caked cavers were still working toward a remote section where the known map petered out. Their goal: To survey and map snaking limestone passages in support of conservation and scientific research.

“It’s like mountain climbing, except you don’t know where you’re headed,” said Charles Fox, eastern operations manager for the Cave Research Foundation.

While the nonprofit foundation’s collection of volunteer cavers and experts have been largely responsible for charting the world’s longest cave — more than doubling its known size in the last four decades alone — their work is about more than just filling in the map.

Along with 400,000 visitors who tour Mammoth Cave National Park’s 14 miles of developed trails each year, Mammoth also attracts flocks of biologists, geologists and anthropologists who venture much deeper. Drawn to its size, cave life and the accessibility of 26 entrances, as many as 50 scientists at any given time are conducting studies on everything from endangered albino cave shrimp to early American Indians and cave hydrodynamics.

“Mammoth Cave is one of the world’s big magnets of cave science,” said Roger Brucker, 85, a co-founder of the foundation, which not only provides detailed maps with geological, biological and anthropological features but also helps take scientists and filmmakers into the cave’s farthest reaches.

But mapping isn’t a cake walk. Cavers are often underground for 30 hours on trips that include 1,000-foot belly crawls and technical rope climbing. They get wet, tired and cramped. Some have been lost for several hours. Although no one has been seriously hurt, there is no immediate rescue for anyone who gets injured. Nevertheless, many foundation volunteers have returned for decades.

“I’ve been the first person in places no one has ever been before,” Fox said. “Some places haven’t been seen since the Native Americans have been there. And it’s like helping solve a puzzle.”

On a recent humid morning just outside the park, cavers participating in the annual weeklong expedition emerged from bunkhouses at the foundation’s complex. Cars bore stickers of bats and there was a license plate that read “I CAVE.” Nearly 20 cavers from a handful of states sipped coffee as Toomey and others went over the day’s trips. One team would survey a former commercial cave. Another was sent to find connections in a recently discovered passage.

Typically, their missions are requested or approved by the National Park Service.

Toomey, who is also a cave paleontologist who coordinates scientific research as the director of the park’s International Center for Science and Learning, reminded everyone to decontaminate gear afterward to avoid spreading white-nose syndrome, a fungal disease that is killing cave bats. And he issued a safety warning.

“There are a number of ways to get hurt in a cave,” Toomey said.

Soon cavers were gearing up, adjusting helmet straps, snapping fresh batteries into headlamps and pulling on thick knee and elbow pads. They donned coveralls and stuffed waterproof packs with food, water, pencils, notebooks, clinometers, flagging ties, measuring tape and compasses. They listed their return times, so that searches could kick off if they were two hours late.

Within an hour, Toomey and his wife, Elizabeth Winkler (they met caving), followed Fox down a restricted road to a cave entrance partly developed for tours before it was abandoned during World War II. Steep steps descended through rock and into a trail filled with cave crickets, which eventually gave way to areas of rock fall, caverns and drop-offs. Crunching in the silence, their trek took them past broken oil lamps, abandoned shoes and rusted sardine tins from the 1930s and 1940s. Footprints made decades ago were frozen in the dust, as if on the moon. In one spot, ancient shark teeth were embedded in the wall.

“One of the reasons Mammoth is so long and stable is that this part of the country was part of a shallow inland sea at one time, hence all the limestone,” Fox said. “As the seas receded, it apparently ended up close to a river mouth, so on top you have a thick layer of sandstone. Limestone dissolves readily in the groundwater, sandstone does not.”

American Indians went into the caves as far back as 4,000 years ago. In the early 1800s, settlers mined saltpeter for gunpowder. In the 1840s, slave and guide Stephen Bishop was one of the first to make initial maps of parts of the cave. In later years, the cave grew as a tourist attraction, with many private caves in the area competing for visitors. Mammoth Cave became a national park in 1941.

Drawn by the mystery of the cave’s size, Brucker started exploring the area in the 1950s, finding a connection between the nearby Flint Ridge System’s Crystal Cave and another cave. Realizing it would take decades or longer to map the system, he helped form the foundation and persuaded the park service to let its volunteers explore Mammoth Cave. In 1972, the group found a connection between Flint Ridge and Mammoth Cave — a major discovery that made it the longest mapped cave in the world at 144 miles. Since then, the group has helped increase the system’s length to 405 miles.

“That expansion has been going on continuously,” Brucker said. “We have predicted that it probably is going to hit 1,000 miles someday — not in our lifetime but in the next century.”

The foundation also works at other sites, including Carlsbad Caverns in New Mexico and Crystal Cave in Sequoia National Park in California.

Sarah Craighead, superintendent of Mammoth Cave National Park, said the group has “skills that are hard to replicate, and we don’t have enough staff to do that level of work. Last year they put in over 10,000 hours in mapping.”

She said the volunteers regularly help with film crews or use ropes to get researchers into difficult reaches of the cave. They recently helped move heavy logs that needed to be preserved as part of the restoration of early 1800s saltpeter works.

Patricia Kambesis, a geologist and cave researcher at Western Kentucky University, said the maps they produce help in making models for research.

By late afternoon, Toomey, Fox and Winkler had hiked, climbed and crawled through rock piles, small passages, soaring domes and drop-offs in a section called New Discovery, dubbed in the 1930s. They passed pools with translucent crayfish and walls plastered with gypsum blooms that looked like flowers. Several times they spotted passages that hadn’t been explored, making notes for future trips.

During breaks, they sat in the dust and rocks, eating candy bars and canned sausages and trading stories about cave trips, including once dragging kayaks into caves to traverse underground rivers. They ticked off some of the cave’s most interestingly named spots: Psychosis Junction. Tight spot. Best Way Up. Tom Wilson’s Accident.

Finally reaching the site dubbed “Canyon of Shadows,” the spot where their last survey had ended was marked by a pink plastic tie. The cavern, about 270 feet below the surface, was a few feet wide and perhaps 20 feet high. It had been mapped before, but only crudely, perhaps 40 years ago, and the map didn’t show new passages they now saw ahead of them.

Breaking out equipment, the explorers started calling out measurements as Fox penciled them into a notebook before sketching a cross section. They tied a new marker, something they’d continue every 10 to 30 feet, depending on the passage’s complexity.

“Bearing?” Fox called.

“Two-two-eight,” Winkler replied.

Winkler climbed through a small hole eight feet up a wall and soon poked her head back out. She’d found a vast new section that included a clear stream. It ran ... somewhere. They decided they’d need to send more teams into the area to explore all the offshoots and perhaps find uncharted areas.

“Looks like we just made more work for ourselves,” Fox said, a grin spreading over his face.

Reporter Chris Kenning can be reached at (502) 582-4697. Follow him on Twitter at @ckenning_cj.