MURPHY, N.C. — It’s midnight, and a jet-like roar is rumbling up the slopes of Poor House Mountain. Except there are no planes overhead, and the nearest commercial airport is 80 miles away.
The sound is coming from a cluster of sheds at the base of the mountain housing a cryptocurrency data center, operated by the San Francisco-based firm PrimeBlock. Twenty-four hours a day, seven days a week, 365 days a year, powerful computers perform the complex computations needed to “mine,” or create, digital currencies. And those noise-generating computers are kept cool by huge fans.
“It’s like living on top of Niagara Falls,” said Mike Lugiewicz, whose home lies less than 100 yards from the mine.
“When it’s at its worst, it’s like sitting on the tarmac with a jet engine in front of you. But the jet never leaves. The jet never takes off. It’s just annoying. It’s just constant annoyance,” he said.
After China cracked down on cryptocurrency mining last year, dozens of cryptocurrency companies and hundreds of independent miners set up operations in sparsely populated parts of the United States, lured by the availability of cheap and plentiful power.
But they have been followed in some areas by noise complaints against the computers and the fans, leading to lawsuits and community action and sharply dividing local populations.
Across America, there are relatively few standards for noise pollution.
Although the Environmental Protection Agency established a noise pollution program in 1972 under the Clean Air Act, the agency has generally left noise issues up to state and local authorities. In North Carolina, noise-control regulations are usually the responsibility of counties, according to the state’s Department of Environmental Quality.
North Carolina’s Cherokee County, where the PrimeBlock cryptocurrency mine is located, has had a noise ordinance on the books since 1999, but locals say it is unevenly enforced and does not specify a decibel threshold.
Enhanced by weather, topography and the surrounding silence in this remote part of Appalachia, the unrelenting noise quickly became intolerable for Lugiewicz, who moved to Poor House Mountain from Brooksville, Fla., in 2005.
“As soon as they started the first container, we said: ‘That’s it. We’re done,’ ” Lugiewicz said.
Staying connected in the field
To better understand the conditions created by cryptomining operations, journalists used AT&T environmental sensor hardware to measure sound quality in a rural area. This story was reported, written and created by The Washington Post. AT&T provided technical support and had no role in the content.
A sensor placed on Lugiewicz’s property by The Washington Post captured noise levels roughly every five minutes over nearly three weeks. In nearly every reading — 98 percent of the time, day or night — decibel levels were above 55, about the noise of a normal conversation.
More than 30 percent of the readings exceeded 60 decibels — high enough that if they were in D.C., they would violate the city’s daytime residential noise ordinances. Estimates from the National Park Service show that expected environmental sound levels in the area should be around 41 decibels.
Kurt Fristrup, a former Park Service scientist who studied noise impacts on rural environments, compared the noise near Lugiewicz’s home to living close to a very busy road without normal pulses in traffic.
Imagine “45 sedans traveling close together nonstop on a three-lane road at 35 miles per hour,” Fristrup said.
Chandler Song, a co-founder and co-owner of PrimeBlock who serves as the company’s chief innovation officer, said that he had received no noise complaints from county officials, and that he had personally visited the facility.
“I have been to the site many times during construction,” he said in an interview. “About 200 yards from the site, we stood in front of the house to check noise levels. It sounds like an air-conditioning unit in the yard. Every night, it was like air conditioning.”
However, he said that the mine is building noise insulation walls and that most PrimeBlock sites will adopt newer and quieter cooling systems in the coming months.
County officials did not respond to emails or texts requesting comment.
The Murphy Electric Power Board did not respond to specific questions about the mine or noise complaints but provided a general statement saying: “When an individual or corporation submits an application for electric service, pays the proper construction fees, provides a security deposit, and agrees to abide by our service rules and regulations we strive to provide safe, reliable electric service.”
Lugiewicz, who works mainly from home, soon gave up on using the expansive deck he completed a month before the mine started operations, where he had hoped to perch with his laptops and listen to the birdsong. Instead of using his “outdoor office,” he retreated indoors and soundproofed his home.
He and his wife began building a new home about 1.6 miles up the mountain, far enough away that the mine is only a distant, barely audible hiss.
“We were planning to move anyway, but the mine definitely sped those plans up,” Lugiewicz said.
Poor House Mountain is dotted with stately homes that belie the name. Rows of townhouses and condos sit on the edge of an old golf course that has been shuttered for five years and is slowly being reclaimed by southern grasses and pines.
No one thought much of anything in the summer of 2021 when a long-vacant field across the street from the mountain was cleared and power poles erected. A few small buildings that looked like storage units started going up, and some thought it was just another place for people to stash their stuff. Not pretty to look at but harmless.
But crypto mining requires serious computing power. Creating a single bitcoin requires 1,556.99 kilowatt hours of electricity, according to Digiconomist, which monitors crypto consumption — about the same amount used to power an average house for 53 days.
The crypto mining centers also need those huge fans to cool them, especially during broiling Southern summers.
When crypto mining companies were forced out of China last year, the ample power available from the Tennessee Valley Authority made Appalachia an appealing spot. At least three mines have opened in North Carolina’s Cherokee County since 2020, but as there is no registration requirement for cryptocurrency data centers, finding out how many are operating in the state is difficult.
North Carolina’s secretary of state’s office, which regulates businesses in the state, said crypto mines fall under the North Carolina Utilities Commission. And Sam Watson, general counsel for the NCUC, wrote in an email: “The Commission does not keep a registry of crypto mines” (or any other retail customer).
Local utilities simply need to approve the required paperwork, and local building permits need to be up to date.
PrimeBlock’s Song said the company was drawn to Cherokee County because of the TVA’s supply of renewable energy, created by hydroelectric dams as well as other methods.
The company operates 12 facilities in North America, concentrated in North Carolina, Tennessee and Kentucky, according to a U.S. Securities and Exchange Commission filing.
But some communities have expressed alarm about crypto coming to town. A group of citizens protested a proposed crypto mine in Pitt County, N.C., forcing plans to be shelved this year. In Limestone, Tenn., county commissioners reached a settlement with a crypto mine operator to move a facility to an industrial park.
Unlike cities such as Asheville, N.C., and Johnson City, Tenn., which turned into mini-metropolises during the pandemic, Murphy is still a place where people go to get away. The area attracts people in search of quiet, including many retired police officers and members of the military.
Dennis Futch, who retired as a captain after 28 years in the Army that included tours in Iraq, Afghanistan and Kuwait, bought a place on Poor House Mountain in 2016, following his parents to the area.
“I needed quiet. I had to have it, and that is why I came,” he said.
If there wasn’t total hush, it was nature’s noise — territorial turkeys or summer cicadas, not gun battles or urban caw. Occasionally, there’d be the distant rumble of a truck on U.S. Highway 64, some two miles away.
Now, however, there is almost constant noise, especially prevalent at night, when other sounds are hushed. “Sound levels generally drop at night, so noises that might not seem so loud during the day suddenly become that much more prominent,” said Fristrup, formerly of the Park Service.
He added that the lower temperatures at night in the mountains of Western North Carolina also trap and amplify the sound.
“It’s changed our way of life up here,” Futch said.
The noise has even forced him to come down the mountain to attend county commission meetings, although public places make him uncomfortable.
“Going to town is usually an ordeal for me, and I can sit at home all day and be perfectly content,” Futch said. “I just wanted to see what was going on and what the county would do about it, but it was not easy to go. It was noisy, and I usually stay away from that.”
Even the drive to the meeting was difficult, Futch says, with highway debris or construction bringing up memories of roadside bombs in Iraq and Afghanistan.
He came away from the meeting convinced that nothing could be done and that he was stuck.
“You just can’t easily pick up and move, because nobody’s going to buy your home,” Futch said. “… You could pack up and move to a nice, quiet area and figure, this is where I’m going to spend the rest of my life, and, lo and behold,” a crypto mine moves in next door.
For Gene Johnson, 80, who served 40 years in the Navy as a gunner and engine room officer, the noise has intruded on a retirement he had hoped to spend playing music with friends.
His home on Beaver Ridge Trail is just a quarter-mile from the mine. Though he’s hard of hearing from his years as a gunner, he says, the sound is still overpowering.
Johnson plays in a local band called the Sea Notes, which performs country, classic rock, bluegrass and some Cajun music at clubs and festivals.
He keeps chairs on his front porch, welcoming any company that might meander by wanting to share some songs. But one has to strain to hear the notes over the whirring mine.
“It bothers me, and it’s a nuisance. Playing music is part of my life. You try playing music with that noise. I keep time with the fans from the mine instead of the guys in my band,” Johnson said.
“The noise makes me feel really angry. It’s embarrassing to have people come over and visit you with that noise there,” he said.
But for other locals, the mines offer economic opportunity. In the town of Marble, 15 miles away, the opening of one of the largest crypto mining facilities in the country was met by locals with a collective shrug.
Built in the shell of a former denim mill, Austin-based Core Scientific’s mine operates day and night, but the computers and cooling systems are primarily enclosed. When asked for comment, Sofia Coon, a spokesman for Core Scientific, said the company “has no comment at this time.”
For residents of this mix of double-wides and tidy ranch houses, the noise is not that different from that of the mill that turned out textiles in three busy shifts. Or the chipping mill where logs are processed a mile away.
“It was loud, louder than the crypto mine,” Vicky Martin, a 67-year-old retired nurse, said of the textile mill. She described semis rumbling up to the factory, industrial equipment clanging and shift workers coming and going.
Martin admits that out-of-town visitors are often incredulous that the crypto mine across the street doesn’t bother her.
The noise levels from the mine regularly reach 60-plus decibels. But she says, while enjoying the view from her back deck: “Life is what you make it. I am not going to let [the crypto mine] take away the joy of my life.”
She went on: “Outsiders stop by and ask me how it can’t bother me, but it doesn’t.”
The complex algorithmic calculations that go into determining what qualifies as noise pollution remain an inexact science. One person’s innocuous white noise is another’s torture.
One of the determining factors is the difference between baseline background noise and the introduced sound, experts say.
The crypto mine near Poor House Mountain is competing with quiet. The one in Marble blends in with the chipping mill and highway noise.
Rachel Buxton, an assistant professor of conservation biology at Carleton University in Ottawa who has studied the impact of noise pollution in rural areas, says that even a five decibel increase can have a dramatic impact.
“Humans have a finite amount of attention. If you are too busy paying attention to noise, there is less cognitive ability for other things,” Buxton said.
That additional noise load can cause stress and lead to negative health effects, she says.
For wildlife, the picture is even worse, Buxton says.
“At its very simplest, the noise can mask important sounds, like wildlife listening for approaching predators or listening for mates. Covering up these sounds can be the difference between life and death,” Buxton said.
And even noise that doesn’t outwardly bother people can have noticeable health effects, according to Stephen Stansfeld, a professor of psychiatry at Queen Mary University of London who has studied the issue.
He said continual exposure to noise can cause elevated blood pressure, which can increase the risk of stroke and heart attack.
“Even if you are sleeping through the noise, it still is having an effect,” Stansfeld said, adding that people’s expectations play a significant role.
“If they are expecting a place to be quiet, then the noise can really get them down,” he said.
Stansfeld also says that people’s connection to noise can affect their perception.
“If someone lives near an airport and they work at the airport, the noise doesn’t bother them, because that is their livelihood,” Stansfeld said.
Some of nature’s noise can register loudly on the decibel scale: tree frogs and flocks of birds, for instance. But Stansfeld says those sounds are not continuous and are part of the built-in expectations of people who have chosen to live in a natural area.
Introducing a continuous source of unwanted man-made noise is a different issue, he says.
“This is even more true in people suffering from PTSD, where these noises can sometimes trigger unpleasant memories of trauma,” Stansfeld said, referring to post-traumatic stress disorder.
Stansfeld says introducing noise into an environment can affect people’s sense of control over their lives, leading to long-term anxiety as well as other psychological and physiological effects.
That’s what Patricia Callahan says happened to her. Three years ago, she bought a condo a quarter of a mile from the base of Poor House Mountain. Then came the crypto mine.
“It has ruined my life,” she said.
Callahan says she filed a noise complaint with the Cherokee County sheriff in October 2021, shortly after the mine became operational. An officer met with her and took notes on her complaint. “But I never got a call back,” Callahan said.
She says the sound has destroyed her efforts to recover from a debilitating car crash in 2008, in which a teenage driver T-boned her car as she was driving her three children home from school.
The young man who plowed into her didn’t survive. Callahan says she was left with traumatic brain injury and the need for specialized prism eyeglasses, forcing her to drive hours to see an optical specialist for regular care. Most of all, she says, she needed quiet.
Now, Callahan says, the mine’s noise crowds her thoughts. And it is louder at night and on weekends, she says, the very times she is trying to relax.
But Song says the computers run at the same capacity all the time. “They are operating consistently at the same level 24/7,” he said.
“When there is noise happening, it takes up space in my brain where I can’t do other things,” Callahan said, closing her eyes and rocking as she talked.
She has taken to sleeping with earplugs and monitoring the noise through a decibel app on her phone. She tracks the sound for anyone who will listen to her, presenting the record to county commissioners and posting the numbers to local Facebook groups.
Callahan looks for patterns and trends, anything that will help her understand — and avoid — the noise.
“I don’t know what to do. Some days I want to put my stuff in storage, buy a van and travel,” Callahan said. “I don’t want to do that. But there’s no good solution.”