Cosmic Prospecting in Lead, South Dakota
by Marshall Swearingen
On a hill above this town of 3,100 people, tucked in the pines of the Black Hills, headframes still stand like sentinels. Their corrugated-steel faces bear the fading emblem of the Homestake Mining Company, the former core of Lead – pronounced "leed," a mining term for the gold veins that lured prospectors in the 1870s. During Lead's gold-mining heyday, which lasted into the 1990s, the headframes lowered 700 miners a day in crowded cages to tunnels deep underground, where they drilled and blasted for the raw material of Lead's prosperity.
But on July 13, 2013, the scene at the Yates Shaft headframe is vastly different. In the parking lot, amid former Homestake offices and machine shops, people of all ages are gathered for a kind of science fair. Some peer through telescopes at solar flares, while others watch demonstrations of solar panels and water filtration systems.
They're also eager to get a glimpse of the old mine. Donning hardhats, dozens file into the hoist room, where giant spools of wrist-thick cable still raise and lower the cages. These days, however, the cages are packed with scientists, who go deep underground in search of discoveries on the frontiers of physics.
This mine is now the Sanford Underground Research Facility, owned and operated by the state government, with the U.S. Department of Energy providing funding and management support. And July 13 is Neutrino Day, Lead's annual festival, named for the tiny, elusive particles that are considered so important, scientists studying them have won three Nobel prizes. Because neutrinos can best be studied deep underground, this old mining town has made the unlikely decision to transform itself with Big Science – the stuff of high-tech centralized labs and federal budgets.
Neutrino Day also enlivens downtown Lead. A school bus shuttles tourists to the 99-year-old Historic Homestake Opera House, where Rick Gaitskell, a physicist from Rhode Island's Ivy League Brown University, is on stage. He speaks in a polished British accent about his search for "dark matter," one of the great unclaimed prizes in the field of particle astrophysics, and something that also might be studied effectively in the mine's depths. Down the block, a restaurant advertises $8.99 Double Dark Matter Cheeseburgers. And in the Lead Deadwood Arts Center gallery, 22 South Dakota artists display their own interpretations of dark matter in mind-bending sculptures and paintings. One, titled A New Millennium of Knowledge – In Search of Dark Matter, depicts a Homestake headframe beside a unicorn and an atom buzzing with electrons.
By the time Neutrino Day 2013 winds down, an impressive 1,100-some scientific tourists have participated, the biggest turnout since the Chamber of Commerce launched the festival in 2001. Back then, when Lead was courting the lab to compensate for the mine's closure that year, Neutrino Day was less a tourist event than a determined show of support from local businesses and boosters. Even though the shift to Big Science hasn't made the town rich yet, many people echo the Chamber's website, which declares: "Lead's future lies in the Sanford Laboratory."
"It's a big deal for our little town, which has struggled and struggled over the years," says Karen Everett, a former Homestake employee who's now the director of the Lead Deadwood Arts Center, "to all of a sudden be on the world map for physics."
In coming years, the discoveries made here could fundamentally re-order our understanding of the universe, answering questions such as: Why does matter exist at all? But as the next generation of underground experiments takes shape, the lab is also revealing the messy, political underside of Big Science. And this intellectual industry is already reshaping this rural community in surprising ways. If this is the ultimate case of the Old West meeting the New, the two are so far proving surprisingly compatible.
From 1877 until 2001, Lead was a company town, ticking to the shifts at the Homestake Mine. Even the brick and mortar of the town moved with the mine, the streets and buildings buckling from the collapse of tunnels chiseled by Italians and Swedes with eight-pound sledges. The mine's open pit encroached on downtown, and eventually 370 miles of tunnels were dug. Homestake paychecks built homes and shops, while the company itself built the opera house, recreation center and library.
Homestake was one of the richest mines in the country, yielding 1,400 tons of gold and enabling the company to extend its operations internationally in the 1960s. It became the deepest mine in the Western Hemisphere. But at 8,000 feet below the surface –– so far down the rock was hot to the touch –– the cost to extract the low-grade ore increased, while gold prices declined. So in a move typical for any commodity-based, boom-and-bust business, Homestake cut its Lead operations by more than half in 1998, and in 2000 announced plans to close the mine by the end of the next year. It was already clear, however, that the mine had other uses – especially for cutting-edge physics research.
Neutrinos are often called "the ghosts of the universe" because they're invisible, electrically neutral and millions of times smaller than electrons. Scientists first postulated their existence in the 1930s, and believe that they're generated by nuclear fusion in stars and possibly by supernovas and other violent cosmic events, as well as by nuclear reactors and nuclear bombs. It's thought that some are even relics of the original Big Bang that created the universe. The Nobel Prize-winning physicist Frederick Reines called them "the most tiny quantity of reality ever imagined by a human being." They "can travel at nearly the speed of light ... without being deflected by magnetic fields or absorbed by matter," conveying "astronomical information from the edge of the universe and from deep inside the most cataclysmic high-energy processes," according to a consortium of universities in 11 countries. Our sun alone generates so many neutrinos that tens of billions of them pass through a person's fingernail every second.
"Even though neutrinos are some of the most abundant particles in the universe, they are essentially the least understood," says John Wilkerson, a University of North Carolina physics professor and principal investigator for a current neutrino experiment in the Sanford Lab. But understanding them, he says, may enable scientists to answer fundamental questions about the fabric of the cosmos, including why more matter exists than anti-matter (particles that combine with and annihilate matter). In other words, he says, the study of neutrinos may help us answer the most basic question of all: "Why are we here?"
On the Earth's surface, the subtle natural drizzle of neutrinos is obscured by a barrage of cosmic rays – bits of atomic shrapnel hurled by exploding stars and black holes. But thick layers of rock block cosmic rays – a capability that has made the Homestake Mine valuable for research since the 1960s, when a team led by U.S. Atomic Energy Commission physicist Ray Davis sought to detect neutrinos in a cavern on the 4,850-foot level, which miners had excavated for the experiment. The team installed a detector – basically a 100,000-gallon tank of dry-cleaning fluid – and, by 1968, registered the occasional faint collision between neutrino and atom, also eventually winning a Nobel Prize. The famous "Homestake experiment," which was the first to observe the sun's neutrinos, inspired other experiments in underground labs around the world.
More recently, physicists also began going underground to study dark matter particles, which have proven even more elusive. Since the 1930s, astronomers have predicted the existence of an unaccounted-for mass that comprises more than 25 percent of the universe, binding together galaxies and other celestial bodies. Like neutrinos, dark matter particles may pass invisibly through the Earth as we pinwheel around our galaxy at hundreds of miles per second.
"Dark matter may have had profound effects on the evolution of the galaxy and the universe," says Jaret Heise, a Canadian with a graying ponytail who speaks about the cosmos as casually as one might speak about the weather. He used to conduct neutrino experiments in the Sudbury Neutrino Observatory, 6,800 feet down in a nickel mine in Ontario, Canada, and now serves as the Sanford Lab's science director. "It's likely that it was the kernel around which our galaxy formed."
As questions about neutrinos and dark matter became central to advancing the physics frontiers, access to underground labs grew more crucial. The U.S. had only a few relatively shallow sites that were fully dedicated to research, including an abandoned iron mine in Minnesota, so U.S. researchers often had to rely on well-funded underground labs burrowed into Italian and Russian mountains or tucked into a Japanese mine. A National Research Council report, begun in 2000 and published in 2003, joined many other expert voices calling for the development of a convenient deep underground lab in the U.S.
"We are at a special moment in our journey to understand the universe and the physical laws that govern it," the National Research Council said, acknowledging that "these questions strain the limits of human ingenuity." Yet no one foresaw the challenges involved in trying to transform the Homestake Mine into the world's premier underground lab.
By the time the last load of ore was hoisted up the Homestake Mine's shafts in December 2001, Democratic South Dakota Sen. Tim Johnson had secured $10 million, part of an appropriations bill signed by Republican President George W. Bush, to help build a national lab here. Scientists rallied around a National Science Foundation proposal to turn the mine into their dream, the National Underground Science Laboratory, a $200 million complex where biologists and geologists could probe the tunnels for deep-earth organisms and core samples, and physicists could conduct large experiments in refinished rooms carved from the rock to depths of 7,400 feet.
Two key scientists hailed the mine's research potential in the Rapid City Journal, predicting it would lead to "the development of new materials important to industry, the design and testing of various detectors crucial to national security and defense, and novel opportunities for future advances in earth science, microbiology, electronics, computer engineering, etc."
There were plenty of reasons for locals to support the proposal. For one thing, it meant pumps would continue to keep underground water from filling the tunnels, staving off the spread of acidic, toxic runoff – one of the problems common to closed-down heavy metals mines. It also carried a whiff of excitement, recalling the time "Champion Wire-walker" Ivy Baldwin tight-roped 800 feet across the Homestake open pit in 1916. And, most of all, it would extend the Homestake Mine's long run.
"This mine had been going so long, you had fourth-generation mining families," says Jim Hanhardt, who started work at Homestake in 1988 as a miner and a shaftman. "To a lot of people, this was the only employment they knew. Everybody hoped (the lab) would happen soon enough, they wouldn't have to move away to different jobs."
Lab boosters stoked those hopes. South Dakota School of Mines and Technology President Richard Gowen, whom Gov. Mike Rounds would later appoint as head of the Homestake Laboratory Conversion Project, told miners, "You know the rock, you know the mine and you're the people we want," according to the Black Hills Pioneer. The Journal described a hand-written sign left on a pile of blasting caps on the 7400 Level during the last mining shift: "Save for the NSF."
The mine-to-lab conversion, however, hit an obstacle immediately. The same month the last ore was extracted, Toronto-based Barrick Gold Corporation bought out Homestake, aiming to tap the company's 125 years of experience on its way to becoming a global giant. Barrick agreed in principle to donate the Homestake Mine to science, but feared lawsuits over injuries and environmental problems. When Democratic South Dakota Sen. Tom Daschle championed a bill to shield the company from liability, he drew fire not just from environmentalists – who thought it would set a bad precedent for mine reclamation – but also from political rivals. Conservative talk show host Rush Limbaugh – always seeking an angle against liberals, even if it meant a momentary alliance with environmentalists – blasted Daschle for giving Barrick "a free pass on polluting the environment with toxic waste."
The partisan sparring and unresolved liability stalled negotiations at the national level, even as Lead and neighboring cities and counties passed resolutions supporting the lab. Barrick continued to resist the complicated mine-transfer deal, despite a pleading letter from 14 Nobel Prize-winning scientists and legendary physicist Stephen Hawking, and in June 2003, the company shut down the pumps. Some physicists began proposing other lab sites.
With the lab proposal here unraveling, the mine's closure "had a tremendous impact on the town," says Hanhardt, who worked on the final crews shuttering the mine until 2003. "The prices on housing dropped, people had to move away. ... It just caused a lot of turmoil."
Then, in 2004, Gov. Rounds, citing the billions of dollars of economic development the lab might bring to the Black Hills, pushed the state Legislature to resolve the liability concerns by creating the South Dakota Science and Technology Authority. The new agency would resemble entities created by other states to cash in on science research, but its main purpose was to assume full ownership of the defunct mine and take Barrick off the hook. In 2006, the company gave the state the mine property, including 186 surface acres.
But the delay allowed other Western communities to enter the competition for a new underground lab. The proposals ranged from expanding the Department of Energy's Waste Isolation Pilot Plant in New Mexico to using railroad tunnels under the Cascade Mountains near Seattle. In 2005, the National Science Foundation narrowed the proposals to Homestake and the Henderson molybdenum mine in Empire, Colo., largely because both sites, by virtue of being mines, were already excavated and had much of the necessary infrastructure, such as hoists. Empire, like Lead, saw a chance to dodge a mining bust.
It wasn't the first time that Westerners had competed for Big Science. In the late 1980s, most Western states vied for the Superconducting Super Collider, a 53-mile circumference, $4.4 billion project that would have been the world's largest atom-smasher, another important tactic in particle physics. "We can smell the supercollider. ... It smells like greenbacks," Utah Lt. Gov. Val Oveson told the Denver Post. In South Dakota, the Legislature approved $63 million in incentives and offered to condemn and purchase land for the Super Collider. The feds eventually chose Dallas, Texas, and pumped more than $2 billion into construction there, before Congress, concerned about ballooning costs, cancelled it in 1993.
Courting a physics lab for the Homestake Mine – an even larger incarnation of the original proposal, retitled the Deep Underground Science and Engineering Laboratory – South Dakota pledged $34 million for the nuts-and-bolts work of retrofitting the mine. Another $70 million came from T. Denny Sanford, a South Dakotan who made the Forbes billionaire list by issuing credit cards with high fees and up to 79.9 percent interest rates to people with bad credit scores through the bank he owns, First Premier. (Sanford had already plowed hundreds of millions of dollars into children's hospitals at the advice of friend Newt Gingrich.) But the bulk of the lab's funding depended on the National Science Foundation's approval.
Another round of suspense ended in 2007: A National Science Foundation committee unanimously selected Homestake, citing several factors, including the mine's depth and the character of the rock, which formed an effective shield for experiments. The state's Science Authority started rehabilitating the shafts and pumping out the water. Then more obstacles arose. The National Science Foundation had allotted $29 million to help design the lab, but it turned down a request for double that amount to deal with unexpected water and safety concerns.
In 2010, the National Science Foundation decided not to take a managing role, saying the Energy Department was better suited for the job. The decision derailed grand plans for creating a Deep Underground Science and Engineering Laboratory in the Homestake Mine. But one of the oldest and biggest federal labs in the West – the Energy Department's Lawrence Berkeley National Laboratory at the University of California-Berkeley, where particle accelerator experiments in the 1930s gave rise to Big Science, and where research ranging from climate change to biology continues today – agreed to manage a scaled-down version. It would start off with a few high-priority physics experiments on the 4850 Level (where Davis' neutrino experiment still stood), while also opening the tunnels to geologists and biologists. And it was renamed after Sanford, as the importance of his donation was magnified by the National Science Foundation's withdrawal.
Local contractors hastened the mine retrofit, stretching miles of wire and ductwork down the shafts, hauling tons of rebar, gravel and concrete on the hoists, and turning the dark, narrow, dirt-floored tunnel on the 4850 Level into the "Davis Campus" – a 30,000-square-foot lab with a machine shop, flush toilets and Wi-Fi. After more than a decade of political wrangling, on May 30, 2012, dozens of scientists in hardhats gathered to celebrate what was in effect the underground lab's opening day.
"Other than the hardhats, you kind of forget you're a mile underground," Jim Hanhardt's son, Mark, tells me via videoconference from the Davis Campus when I visit the lab shortly after Neutrino Day. Along with a couple dozen other scientists and lab workers, he's just taken the 11-minute ride down the dark shaft in the same cage that his dad rode as a Homestake miner. Wearing safety glasses and a stubbly beard, he jokes with boyish enthusiasm as he explains what's going on with the experiments.
Mark Hanhardt calls himself "a jack of all trades, master of physics." During his days underground, he does odd jobs like repairing equipment, and he's also a 32-year-old grad student at South Dakota School of Mines and Technology, a technical college with 2,400 students in nearby Rapid City, whose sports teams are named the "Hardrockers." He's involved in the lab's Large Underground Xenon, or LUX, dark-matter experiment, which has caught the interest of physicists around the world.
Particle astrophysics research proceeds the way all science does, from hypothesis to established theory. But it may be the only field in which scientists spend billions of dollars trying to prove the existence of something, like dark matter, that may not exist at all. This kind of Big Science, as many have predicted, could spin off new medical devices or weaponry the way early nuclear research yielded MRIs and warheads. But the scientists in this field are driven less by possible practical applications than by a restless desire to comprehend the cosmos, to find the patterns underlying both its unutterably vast and tiny realms. It's no wonder they have a habit of condensing their world into acronyms that baffle or amuse the uninitiated.
Weakly interacting massive particles, or WIMPs, are the theoretical bits of dark matter that researchers hope to observe with the LUX. This experiment consists mainly of a trashcan-sized titanium canister filled with liquid xenon and suspended in a tank of water that further buffers the outside radiation. Like Davis' "neutrino tank," the LUX acts like a net, registering a distinct signal if struck by a passing WIMP. But on Oct. 30, after an 85-day search for WIMPs, scientists announced that the experiment – despite being more sensitive than any of its predecessors – had yet to observe any WIMPs.
On a typical recent day, scientists in steel-toed boots shuffle back and forth in the Davis Campus corridor. Others slip on hooded Tyvec jumpsuits and facemasks, preparing to enter a cleanroom. Inside, scientists are making the world's purest copper, by dissolving already purified chunks of copper from Finland in acid and re-forming it to prevent contamination from cosmic rays. It's then machined into parts for a neutrino experiment called the Majorana Demonstrator (named after "a brilliant Italian theoretician who had a brief career in the 1920s and '30s but vanished mysteriously at the age of 32"). This experiment will measure the radioactive decay of hockey puck-sized germanium crystals placed within a copper detector, shielded against even trace amounts of radiation from the surrounding rock by a castle of 5,000 lead bricks. The goal is to confirm "neutrinoless double-beta decay," a theoretical subatomic process that has never been observed. The results could help explain how matter outweighed anti-matter and created the known universe.
Over time, the Sanford Lab could grow to house more experiments, possibly as many as were envisioned for the grand original lab proposal. One in planning stages, with a nearly $1 billion price tag, is called the Long-Baseline Neutrino Experiment. It would catch a beam of the particles shot from the Energy Department's Fermilab near Chicago, observing how they morph as they pass through the Earth. Some physicists think it could be the country's flagship experiment, but it's also under budget pressure. The Energy Department's science budget has dwindled since 2010, as it shifts research toward energy conservation and climate change, the Obama administration's priorities. Still, at the Sanford Lab there's an optimism from seeing experiments up and running. "For the next couple decades, at least," says Mark Hanhardt, "we're going to see a lot of Big Science underground."
The work itself is not easy. Wilkerson's Majorana team – a dozen graduate students, post-docs and fellow professors – sometimes works double shifts on the 4850 Level during critical stages of the experiment. Like most of the other researchers, they stay in Lead for only a week or month at a time, rotating through rented houses. Others hail from universities as far away as Canada, Russia and Japan. Lead has everything they need, says Wilkerson, and it's a nice place to get outdoors during their brief free time. "Probably the biggest hardship," he says, "is that people are away from their families."
The scientists' transience and the budget pressures are partly why the lab has had less of an economic impact than locals hoped. Underground research is a specialized and relatively small field, tending to draw scientists who are tethered to their home universities. The biggest underground lab in the world, Italy's Gran Sasso National Laboratory, draws some 900 scientists but has no more full-time staff than Sanford.
And within the realm of Big Science, Sanford Lab is small. The Pacific Northwest National Lab in Richland, Wash., and the Idaho National Lab in Idaho Falls – both run by the Energy Department – have billion-dollar budgets and thousands of employees, working on dozens of applied-science research projects ranging from bio-energy to nuclear fusion. In recent years, the Energy Department's Los Alamos, N.M., lab has ranked as the state's sixth-largest employer. The Sanford Lab's budget, in rough numbers, is $20 million per year, including
$13 million from the Energy Department, $4 million from the Sanford donation, and $2 million from the state.
But in Lead, the lab's $12 million payroll and more than 120 jobs go a long way. "It's the major employer in the community," says Mike Stahl, Lead's city administrator, who used to be a Homestake mining engineer. About 70 lab employees formerly worked for Homestake in one way or another. The lab depends on people with mining experience; they maintain and run the equipment, refurbish the shafts using special chainsaws and black-powder "microblasters," and install new steel supports so that the hoists can handle bigger, future experiments. Other former Homestake employees work at the lab as administrators, security guards and wastewater technicians. Full-timers get health insurance, three weeks' paid vacation and other benefits.
The traveling scientists "buy supplies (and) eat at restaurants," says Stahl. "There are a few art galleries they like to go to." Dena Sheets, a local property manager who rents houses to several of them, says the lab overall "has been a real shot in the arm for this economy." Especially during winter, when the roar of motorcycles headed to the annual national rally in nearby Sturgis has died down and the tourist economy limps along on winter recreation, "you can definitely tell when there is something going on at the lab," says Melissa Johnson, director of Lead's Chamber of Commerce. "It's pretty easy to spot (the scientists): They're not wearing snowmobile gear."
Evidence of the Homestake Mine bust remains visible. The union hall is now a bar, with a used-clothing store in back. Rows of vacant shops line the old downtown; "For Sale" signs dot the neighborhoods. Smaller-scale mining, employing about 150 people, continues a few miles west of town at a cyanide heap-leach operation run by Goldcorp, another Canadian company. But "people are kind of settled into the next stage," says Stahl. "They're past resenting the loss of the mine."
The impact of Big Science on the West has always been more complicated than the basic jobs and dollars. Richland prospers on high-tech business spun off the Pacific Northwest National Lab, but also inherited a legacy of nuclear contamination at the nearby Hanford site, which produced plutonium for weapons from the 1940s to the 1980s. Los Alamos has a nationally recognized high school nurtured by its rural pod of Ph.D.s, but a sense of isolation lingers like a decayed isotope from the secrecy of that town's World War II-era nuclear bomb-building. In Lead, there's a sense that Sanford Lab fills the void that opens like a wound when mining towns go bust. The underground science, which seems harmless compared to nuclear research, has given this small community a new sense of purpose.
"Lead still has a lot of retired Homestake employees and their families," says Stahl. "When the Sanford Lab has presentations, that room is full of those people. They're there because they find it interesting."
Jim Hanhardt recalls his previous life as a "tramp miner," going from town to town as metal prices climbed and fell. After his job with Homestake ended in 2003, he left for stints in California and then Montana. But "I had always had my eye on coming back," he says. "This was home. (My wife and I) raised our kids here."
When I meet him in the lab, near the hallway where the scientists suit up in coveralls for their ride down the shaft, his mining years show. He wears tiny hearing aids after years of operating machinery, and one finger bears a scar from an accident in a Colorado mine. He hands me a photo of a motorcycle he built. "Science is something I've always been interested in," he says.
A job with a contractor doing the shaft rehab in the lab drew him back to Lead in 2008. Two years later, the lab hired him directly, to continue to manage the retrofit and oversee other aspects of the lab operations, using his mining expertise. Like others here, he's hesitant to compare the lab to the mine. "Homestake employed a lot of miners, but (the lab) is a little bit different," he says. "Support of science brings in a bunch of new opportunities that weren't even envisioned back in the Homestake days."
He could be thinking of the local high-school kids doing class projects with the lab, or of recruits from the 4,400 students at Black Hills State University, in nearby Spearfish, who get summer internships here. Or how the state's Science Authority pays for a group of South Dakota high school grads to study physics for a month at the Energy Department's Fermilab and underground labs in Europe. All are part of Science Authority's mission "to foster transformational science education" in addition to running the lab. That mission will soon be anchored in a new $4.5 million education center at the Black Hills University campus, and the Sanford donation will be tapped for more than half of that cost. The center will, among other things, train the region's K-12 science teachers to create "a community culture of appreciation for the pursuit of knowledge," says Ben Sayler, the lab's director of education and outreach.
Jim Hanhardt is probably also proud that his son is one of the state's first physics Ph.D. students in decades. The South Dakota School of Mines' former physics Ph.D. program winked out in the 1950s, and until recently, this state and Vermont were the only states where students couldn't attain that degree. When lab proponents first came to South Dakota to drum up support, "there just weren't many physicists in (the state)," says Tina Keller, director of the physics program at University of South Dakota, where half of the 12 new Ph.D. candidates are enrolled. The lab pushed the state's universities to get involved in the research, and this year the Legislature began to provide funding for the new Ph.D. program, which could grow to more than 40 students. The Ph.D. students are the kind of people you want to keep around, Keller says. "They're creative, they're young, they have a lot of energy."
On Aug. 20, their first day of school, the new Ph.D. students meet in the lab for an orientation. Mark Hanhardt poses with the rest for a photo in front of the old shaft headframe. Some of the students will be on the 4850 Level daily, working on research and taking breaks to attend classes – via videoconference – transmitted from the University of South Dakota, 450 miles away.
"It's not unusual for me to be the only American in a room here," Mark says, down on the 4850 Level. "Being with that mix of cultures, but with everyone driven toward the same goal of ripping open the cover of the universe and taking a peek inside, that's exceptionally rewarding."
Marshall Swearingen, a former HCN intern, is now freelancing from Bozeman, Montana.
Matt Kapust, a South Dakota native who began working at the Sanford Lab as an intern while attending Black Hills State University, provided most of the photographs for this story from work he's done as the lab's multimedia specialist. Additional images were taken by his former photography professor, Steve Babbitt.
This story was funded with reader donations to the High Country News Research Fund.© High Country News