On an evening in December 2023, 43-year-old small business owner Sarah Rosenkranz collapsed in her home in Granbury, Texas and was rushed to the emergency room. Her heart pounded 200 beats per minute; her blood pressure spiked into hypertensive crisis; her skull throbbed. “It felt like my head was in a pressure vise being crushed,” she says. “That pain was worse than childbirth.”
Rosenkranz’s migraine lasted for five days. Doctors gave her several rounds of IV medication and painkiller shots, but nothing seemed to knock down the pain, she says. This was odd, especially because local doctors were similarly vexed when Indigo, Rosenkranz’s 5-year-old daughter, was taken to urgent care earlier that year, screaming that she felt a “red beam behind her eardrums.”
It didn’t occur to Sarah that these symptoms could be linked. But in January 2024, she walked into a town hall in Granbury and found a room full of people worn thin from strange, debilitating illnesses. A mother said her 8-year-old daughter was losing her hearing and fluids were leaking from her ears. Several women said they experienced fainting spells, including while driving on the highway. Others said they were wracked by debilitating vertigo and nausea, waking up in the middle of the night mid-vomit.
None of them knew what, exactly, was causing these symptoms. But they all shared a singular grievance: a dull aural hum had crept into their lives, which growled or roared depending on the time of day, rattling their windows and rendering them unable to sleep. The hum, local law enforcement had learned, was emanating from a Bitcoin mining facility that had recently moved into the area—and was exceeding legal noise ordinances on a daily basis.
Over the course of several months in 2024, TIME spoke to more than 40 people in the Granbury area who reported a medical ailment that they believe is connected to the arrival of the Bitcoin mine: hypertension, heart palpitations, chest pain, vertigo, tinnitus, migraines, panic attacks. At least 10 people went to urgent care or the emergency room with these symptoms. The development of large-scale Bitcoin mines and data centers is quite new, and most of them are housed in extremely remote places. There have been no major medical studies on the impacts of living near one. But there is an increasing body of scientific studies linking prolonged exposure to noise pollution with cardiovascular damage. And one local doctor—ears, nose, and throat specialist Salim Bhaloo—says he sees patients with symptoms potentially stemming from the Bitcoin mine’s noise on an almost weekly basis.
“I’m sure it increases their cortisol and sugar levels, so you’re getting headaches, vertigo, and it snowballs from there,” Bhaloo says. “This thing is definitely causing a tremendous amount of stress. Everyone is just miserable about it.”
Not all data centers make noise. And industry insiders say they have a technical fix for the ones that do, which involves replacing their facilities’ loud air fans with much quieter liquid-based cooling solutions. But some of their touted methods, including “immersion cooling” in oil, are expensive and untested on a large scale.
A representative for Marathon Digital Holdings, the company that owns the mine, did not answer questions about health impacts, but told TIME that it is working to remove the noisy fans from the site. “By the end of 2024, we intend to have replaced the majority of air-cooled containers with immersion cooling, with no expansion required. Initial sound readings on immersion containers indicate favorable results in sound reduction and compliance with all relevant state noise ordinances,” they wrote in an email.
The number of commercial-scale Bitcoin mining operations in the U.S. has increased sharply over the last few years; there are now at least 137. Similar medical complaints have been registered near facilities in Arkansas and North Dakota. And the Bitcoin mining industry is urgently trying to push bills through state legislatures, including in Indiana and Missouri, which would exempt Bitcoin mines from local zoning or noise ordinances. In May, Oklahoma governor Kevin Stitt signed a “Bitcoin Rights” bill to protect miners and prevent any future attempts to ban the industry.
While some Granbury residents are fiercely protesting the mine, many others feel powerless to alter the will of a company with legal, political, and financial might. And the data center industry at large is only growing more dominant, thanks to the twin forces of Bitcoin mining and AI, the latter which spends a vast amount of energy training generative models to find patterns in data sets. According to a recent report, data centers will use 8% of total U.S. power by 2030, up from 3% in 2022. And if operators continue to locate the centers near existing communities and prioritize profits above all else, then the story of Granbury could become the story of countless small towns across America.
Granbury sits about an hour southwest of Fort Worth in Hood County, which houses a mostly rural and Republican population of about 65,000 people. About a 15-minute drive south of Granbury’s charming historic town center—which includes a 19th-century opera house—lies a gas plant called Wolf Hollow II. Driving toward the plant on a windy, predawn morning in May, it rises out of the sky like an oil rig in a pitch-black ocean, lights ablaze.
But the glowing gas plant never caused substantial issues for the local residents. Rather, the problems started when Constellation Energy, which operated the plant, signed a deal in 2021 to power a new Bitcoin mining facility that would sit directly on its lot. The new facility consisted of 163 squat metal boxes resembling shipping containers, which housed a total of over 30,000 computers. These computers started running in the summer of 2022, and seemed to be switched on all day and night. As of December 2023, the Granbury mine is owned and operated by Marathon, one of the largest Bitcoin holders in the world.
The computers power a process called proof-of-work mining. Rather than relying on a central bank or governmental agency, Bitcoin is created, maintained, and guarded by watchdogs around the world known as miners, who prevent tampering through a complex cryptographic process and are rewarded with bitcoin for doing so. Bitcoin’s first supporters hoped that this new system would support a global digital currency that would bring freedom, financial fairness, and wealth to its adopters.
But the system also requires an immense and ever-increasing amount of electricity. While Bitcoin’s first miners were solo operators often working out of their bedrooms, the industry is now dominated by a handful of billion-dollar corporations who operate industrial-size server farms across the globe. In the month of March 2024 alone, the Bitcoin mining industry generated a record $2 billion in revenue.
Much of the American Bitcoin mining industry can now be found in Texas, home to giant power plants, lax regulation, and crypto-friendly politicians. In October 2021, Governor Greg Abbott hosted the lobbying group Texas Blockchain Council at the governor’s mansion. The group insisted that their industry would help the state’s overtaxed energy grid; that during energy crises, miners would be one of the few energy customers able to shut off upon request, provided that they were paid in exchange. After meeting with the lobbyists, Abbott tweeted that Texas would soon be the “#1 [state] for blockchain & cryptocurrency.” The following month, the Commissioners Court of Hood County approved the development of a cryptocurrency operation at Wolf Hollow. The owners promised local jobs and said that they would mostly use “stranded energy” that would otherwise go unused.
For months during 2022, Granbury residents Nick and Virginia Browning sat in their front yard watching the new metal boxes of the massive facility be installed in the dirt across the road. “It layered our houses with dust. We haven’t gotten it all out yet,” Nick Browning, 82, says.
The dust, it turns out, was just a prelude to the noise. In order to cool the machines, the site’s operators attached thousands of fans to the containers, which churned constantly, emitting a vicious buzz. As more machines were switched on, the noise sounded like a ceiling fan, then a leaf blower, then a jet engine. It consumed afternoon dog walks and revved through cloudless nights, vibrating the trailer homes of many of the low-income residents who live blocks from the facility. The noise floated miles down the winding Brazos river, through the lush golf courses in the gated community Pecan Plantation and past county lines.
At first, residents responded to the intrusion by vacating their porches, retreating inside, and turning up their fans and air conditioners to the max. But many still felt tremors in their beds—including Larry Potts, a 77-year-old retired pastor who lives up the road from the plant. Potts says he stopped sleeping and started losing hearing in both ears. In February, his heart gave out after another sleepless night; he was rushed to the hospital and kept alive by an external pacemaker. There, he was diagnosed with third degree atrioventricular block, hypertension, and depression.
“I’m sick of this world and all this mess around here,” he says he told his wife that day, referring to the Bitcoin mine’s noise. “We moved out here for the peace and quiet. But this has made me want to go.”
Some nearby residents say they haven’t been affected. But the number of strange medical emergencies in the area have piled up. In addition to Potts’ discharge papers, TIME reviewed medical records provided by several Granbury residents. Hospital notes from 72-year-old Geraldine Lathers’ three-day stay document new prescriptions for high blood pressure and vertigo. Jenna Hornbuckle, 38, lost hearing in her right ear and was diagnosed with heart failure; ear exams document her hearing loss along with that of her 8-year-old daughter Victoria, who contracted ear infections that forced doctors to place a tube in her ear. And Avari Burns, a 19-year-old cancer patient, says she suffered from crippling migraines at home—but whenever she went to a Fort Worth hospital for chemotherapy, the migraines subsided.
Virginia Browning, 81, who can see the Bitcoin mine from her front yard, says she was taken to urgent care with violent vertigo after waking up one night mid-vomit. Browning says she gets so dizzy she can barely walk in a straight line, and that she rarely sleeps through the night. “When they crank this thing,” she says shakily, “I’m wide awake.”
“We’re living in a nightmare,” Sarah Rosenkranz says, sitting at a barbecue restaurant in downtown Granbury on an evening in May. As rock music blares from the speakers and other patrons chatter away, Rosenkranz pulls out her phone and clocks 72 decibels on a sound meter app—the same level that she records in Indigo’s bedroom in the dead of night. In early 2023, her daughter began waking up, yelling and holding her ears. Indigo’s room directly faces the mine, which sits about a mile and a half away. She soon refused to sleep in her own room. She then developed so many ear infections that Rosenkranz pulled her from school in March and learned how to homeschool her for the rest of the semester.
Over grilled salmon and hush puppies, Rosenkranz shares that her family has been sleeping peacefully at an inn downtown for the last three days in order to get away from the noise. But the next morning, after returning home, she contracts yet another migraine that lands her in urgent care.
Dr. Bhaloo, the ENT doctor in Granbury, says he’s seen an uptick since the new year in patients whose ailments—including ringing in their ears, vertigo, and headaches—could be related to the mine. “These people here, they’re good country folks, and Bitcoin, to them, is almost a foreign alien thing,” he says. “They don’t understand it. And [the noise] is detrimental to their health and anxiety.” Dr. Stephen Krzeminski, another Granbury ENT, agrees. “Sonic damage is real, there’s no disputing that,” he says. Krzeminski says he believes the mine is causing “mental and physical” health issues. “Imagine if I had vuvuzela in your ear all the time,” he says.
The level of noise is appalling to Dr. Thomas Münzel, a German cardiologist who is a leader in the growing field of scientific researchers measuring the impact of urban and industrial noise on humans. For the last 15 years, Münzel has studied how transportation and urban noise, especially at night, can be debilitating stressors on the heart, brain, and cardiovascular systems. In one study, he exposed young, healthy students to noise events up to 63 decibels, and found that their vascular function diminished after just a single night. In other studies, he’s found that nighttime noise pollution directly leads to heart failure and molecular changes in the brain, which may lead to impaired cognitive development of children and make some people more prone to developing dementia.
“The European Environmental Agency tells us that everything above 55 decibels is making us sick,” he says. The fact that the Granbury Bitcoin mine is emitting 70 or even 90 decibels on a nightly basis is “like torture,” he says. “The most spectacular cardiovascular diseases will develop. They have to stop the machines.”
Health effects have the potential to extend past the human residents of Granbury. Studies have shown that man-made noise pollution harms animals and wildlife, causing oxidative stress and memory loss in rodents, acute anxiety in dogs, and a decrease in forest growth. Shenice Copenhaver’s dog, Persephone, started going bald and developed debilitating anxiety shortly after the Bitcoin mine began operating four blocks away. Directly next door, Tom Weeks’ dog Jack Rabbit Slim started shaking and hyperventilating uncontrollably for hours on end; a vet placed him on the seizure medication Gabapentin. Rosenkranz’s chickens stopped laying eggs for months. And Jerry and Patricia Campbell’s centuries-old oak tree, which had served as the family’s hub and protector for generations of backyard family reunions and even a wedding, died suddenly three months ago.
It’s nearly impossible to prove the Bitcoin mine directly caused the afflictions of these specific animals and plants. But as the strange anecdotes collect, they’ve added to the stress of a town that feels under siege from all directions.
“I’ve lived in Texas all my life and I’ve never seen an oak tree be beautiful one year and die the next,” Jerry Campbell says on his lawn, beneath the tree’s gnarled, blackened limbs. “It’s so strange.”
Hood County Constable John Shirley has spent months trying to find his own solutions to a problem that at times seems supernatural. As a former member of the Oath Keepers, a far-right militia whose leaders were convicted of seditious conspiracy against the U.S. government, Shirley is a somewhat divisive figure in the town. But lately Shirley has been laser-focused on the mine—an issue he considers apolitical. “When you’ve got Greenpeace supporting the same cause as a former Oath Keeper, what weird episode of the Twilight Zone are we in?” he says, chuckling darkly. (Shirley resigned from the Oath Keepers before Jan. 6, 2021, due to “serious concerns” with the direction of the organization, he says.)
On a listless May morning before the sun has risen, Shirley is sitting in his truck across the road from the mine. He is used to getting up at this hour, as he’s been taking decibel readings of the plant around the clock in order to write tickets against the mine’s operators for disorderly conduct. Shirley sticks his recorder out the window and the numbers on it flicker up and down as the roar washes over it. Eventually, the recorder caps out at 91 decibels, which the CDC estimates as roughly in between the output of a lawnmower and a chainsaw.
This level of noise, the CDC writes, can cause hearing damage after two hours of exposure. The Occupational Safety and Health Administration advises that employees can only work in 90-decibel settings for eight hours a day and are required to wear ear protection. And Texas state penal code deems any noise above 85 decibels unreasonable. Over the course of 2024, Shirley has recorded a noise above 85 decibels coming from the plant more than 35 times.
Technically there is federal mandate to regulate noise, which stems from the 1972 Noise Control Act—but it was essentially de-funded during the Reagan administration. This leaves noise regulation up to states, cities, and counties. New York City, for instance, has a noise code which officially caps restaurant music and air conditioning at 42 decibels (as measured within a nearby residence). Texas’s 85 decibels, in contrast, is by far the loudest state limit in the nation, says Les Blomberg, the executive director of the nonprofit Noise Pollution Clearinghouse. “It is a level that protects noise polluters, not the noise polluted,” he says.
Ultimately, Constable John Shirley can’t stop the machines, because there is no state law forcing the operator of a noisy machine to turn it off. When Shirley writes a ticket for disorderly conduct, it merely triggers a $500 fine, as opposed to jail time or another punitive measure. Hood County can’t even pass a relevant noise ordinance law: only Texas cities, not counties, have the ability to do so.
Shirley’s tickets now add up to a theoretical fine of $17,500 and counting. But that number is chump change for Marathon, which earned $165 million in revenue in the first quarter of 2024 and bragged to shareholders about “record earnings.” And the company is fighting back: They have requested a jury trial to overturn this low-level misdemeanor, which starts July 8. At a pre-trial hearing in May, the company arrived with a full team of lawyers. “To bring two or three full-suited attorneys to a justice of the peace court citation issue: I’ve never seen that,” says Patrick Ryan, a local lawyer who has consulted with Granbury community members about the possibility of a civil nuisance lawsuit. “They’re coming with both barrels.”
A representative for Marathon declined several interview requests with TIME, saying that the company would refrain from commenting publicly until Constable Shirley’s “unwarranted” citations against the plant had been resolved. As Shirley sits outside the facility recording the pulsating drone, his nostrils flare, and his voice rises with impatience. “When I was a murder investigator and someone killed somebody, I had the law on my side,” he says. “With this, it’s like I’m swatting at a rhinoceros.” As he reads the decibel levels on his sound meter, a security guard from the facility steps out of his car and snaps pictures of Shirley’s truck in the dark.
The residents of Granbury feel they’ve been lied to. In 2023, the site’s previous operators, US Bitcoin Corp, constructed a wall around the mine almost 2,000 feet long and claimed that they had “solved the concern.” But Shirley says that the complaints from the community about the sound actually increased when the wall was nearing completion last fall. Since Marathon bought the facility outright in December, its hash rate, or computational power expended, has doubled.
As complaints mounted at the top of 2024, the company contended it did not know about the extent of the sound issues. “We are now the owners, but we are not the operator. USBTC is still the operator. Prior to the purchase, we were not aware of the noise issues,” a Marathon representative wrote to TIME in an email in January. “Now that we own the site and have been made aware of the issue, we are working to gather information and address the situation.”
But documents show that Marathon provided a $67 million loan in May 2021 to the site’s first formal owners, Compute North, to build out the site’s infrastructure, and Marathon’s purchase agreement of the site, dated December 15, 2023, clearly mentions the existence of the $1.9 million “sound wall” built several months prior.
As community complaints reached a fever pitch earlier this year, Marathon held a meet-and-greet on March 29—Good Friday, which rubbed many people in Granbury’s deeply religious community the wrong way. For the handful of people that did show up, Marathon laid out a noise mitigation plan which included turning off idle fans, moving some containers into liquid cooling by April 2024, and installing vegetation and trees around the perimeter.
In an emailed statement to TIME in late June, Marathon said that 58 air-cooled containers have been removed from the site, and pointed to a roadmap which vows to convert 50% of the site’s containers to immersion cooling by the end of the year. A representative for Constellation Energy, which owns the power plant that Marathon connects to, said in a statement that the company is “staying updated on [Marathon’s] efforts to respond to the concerns raised by neighbors… We will continue working closely with Marathon as they take actions to reduce their impacts.”
Marathon says that immersion cooling, in which computers are placed in tubs of oil, will largely fix the noise problem. But the technique has potential drawbacks, including the difficulty of regularly performing maintenance on a computer submerged in oil, says Kent Draper, the chief commercial officer of the Bitcoin and AI data center operator IREN. “Although it’s been around for a long time in the industry, it’s just not that widely adopted,” he says.
Even Marathon expressed skepticism about its ability to convert its many machines to immersion technology in a 2023 year-end SEC Report. “There is a risk we may not succeed in developing or deploying immersion-cooling at such a large scale to achieve sufficient cooling performance,” the company wrote.
In an email to TIME, Marathon wrote: “While we are confident in our ability to scale this new technology, it is our obligation, as a publicly traded company, to identify any potential risks from a financial perspective.”
Granbury community members are exploring political and legal avenues. A petition against the mine in Granbury and its “excessive and unhealthy noise” garnered 800 in-person signatures, and was brought by representatives to the Texas Republican state convention in San Antonio in May, with the hopes of gaining statewide support for some sort of ban. But two local elected officials, Nannette Samuelson and Shannon Wolf, say they tried to take the floor to stump for the issue, but weren’t given time to speak. Samuelson’s goal is now to pass resolutions in commissioners court prompting state senators to draft legislation.
Any statewide legislation is sure to hit significant headwinds, because the very idea of regulation runs contrary to many Texans’ political beliefs. “As constitutional conservatives, they have taken our core values and used that against us,” says Demetra Conrad, a city council member in the nearby town of Glen Rose.
Some community members are also exploring a potential civil nuisance suit against Marathon, in which they would seek an injunction against the company and/or damages. One affected woman, Cheryl Shadden—who has medically-documented hearing loss—has retained the nonprofit Earthjustice to examine potential litigative routes. Deputy managing attorney Mandy DeRoche says Earthjustice is exploring the possibility of taking its own sound readings near the site. The nonprofit has been involved in several lawsuits against crypto mining companies across the country.
“Historically, Bitcoin miners go to the cheapest source of electricity with the least amount of regulation, and they do the cheapest thing possible,” DeRoche says. “It’s one of the reasons why noise pollution from crypto mining tends to be so much worse than traditionally-operated data center operators.”
As Bitcoin continues to gain value, miners are building progressively bigger operations, causing gas plants and other fossil fuel emitters to spring back into action. It is unclear whether states even have the energy capacity to support this new demand: In June, Texas lieutenant governor Dan Patrick tweeted that Texans “will ultimately pay the price” for the growth of crypto and AI data centers, writing that they “produce very few jobs compared to the incredible demands they place on our grid.” Regardless, Bitcoin lobbying groups are attempting to pass pro-Bitcoin-mining bills in state legislatures across the country, which would exempt similar operations from noise ordinances and local zoning laws. People have reported similar symptoms near Bitcoin mines in Arkansas and Williston, North Dakota. Ultimately, Granbury is just one canary of several in the proverbial mine.
In the week before this article’s publication, two more Granbury residents suffered from acute health crises. The first was Tom Weeks, the owner of the hyperventilating dog. On July 2, Weeks, 64, rose after another sleepless night of listening to the mine and realized he couldn’t breathe. He was rushed to a Fort Worth hospital, where he was diagnosed with a pulmonary embolism—a blood clot blocking his lungs—and hooked up to an oxygen tank. Weeks was supposed to testify against Marathon in the jury trial, but is now physically unable to do so. “This whole thing is an eye opener for me into profit over people,” Weeks says in a phone call from the ICU.
The second person affected was the five-year-old Indigo Rosenkranz. On July 6, she suffered from a seizure and was taken to the emergency room, before being routed to a childrens’ hospital in Fort Worth for further testing. Her mother, Sarah, was terrified and now feels she has no choice but to get a second mortgage to move away from the mine. “A second one would really be a lot,” she says. “God will provide, though. He always sees us through.”
