Elon Musk’s artificial intelligence company xAI has installed 59 natural gas turbines for its Colossus 2 data center project in Tennessee without securing federal clean air permits, according to communications between regulators and xAI representatives reviewed by Reuters.
The potential emissions from those turbines far exceed the threshold that would trigger a federal permit requirement, and they would be released near predominantly Black communities that already face disproportionately high rates of lung disease, according to a Reuters analysis based on government data and the regulatory correspondence.
The number of unpermitted turbines identified by Reuters is roughly double what xAI has publicly acknowledged. The company previously said it was running 27 unpermitted turbines for Colossus 2 as of January and has argued that permits aren’t required for them. At least 57 of the 59 turbines sit in Mississippi, just over the state line from the Tennessee data center they serve.
The findings show how surging electricity demand from AI data centers is pushing companies to build off-grid power plants faster than environmental oversight can keep pace, with real risks to public health in the surrounding communities.
A Pattern of Fast-Tracked Approvals
The xAI turbines are among dozens of off-grid power plants proposed or under construction for data centers nationwide. Local authorities often approve these projects in weeks or months, skipping the years of environmental studies and public hearings typically required for power plants that connect to the electric grid.
Mississippi regulators issued a permit in March for permanent turbines at Colossus 2, clearing construction of 41 gas-fired units. That approval came three weeks after the state held its only public hearing on the project.
Ben King, an analyst with the think tank Rhodium Group who reviewed the Reuters findings, said the xAI cluster already ranks among the largest off-grid data center power projects in the country. “This looks to be an unprecedented level of behind-the-meter gas being installed in one place,” he said, referring to off-grid natural gas plants that serve a single customer.
The communications reviewed by Reuters show that xAI, now owned by Musk’s SpaceX, has installed 57 off-grid turbines in Southaven, Mississippi, across the state line from its Colossus 2 data center in Memphis, which supports the Grok chatbot and other AI systems. Records show two additional unpermitted turbines were installed for the project at a separate site whose location Reuters could not determine.
The records came from a Reuters public records request and included emails between Trinity Consultants, which represents xAI and its subsidiary MZX Tech, and the Mississippi Department of Environmental Quality. xAI did not respond to a request for comment.
Civil Rights Groups Sue Over Emissions
The turbines sit at the center of a widening dispute over whether the AI industry is adding disproportionate pollution to communities of color. The NAACP and the Southern Environmental Law Center sued xAI in April to halt the turbines’ operation, arguing the emissions fall under the federal Clean Air Act and that the company shouldn’t be running them without permits. The groups say the turbines are polluting homes, schools and churches in historically Black neighborhoods.
“The scale of it is astonishing,” said Patrick Anderson, an attorney with the Southern Environmental Law Center. “This is an absolutely huge Clean Air Act violation that threatens public health.”
Securing a Clean Air Act permit would have subjected the project to extensive review and public comment, a process that can take years. Mississippi regulators and xAI have argued in court filings that the turbines qualify for an exemption because they’re classified as mobile and intended to run at the site for less than a year. “MDEQ has determined that portable/temporary turbines do not require an air permit,” the state agency said in a statement to Reuters.
The Environmental Protection Agency said in January 2026 that temporary turbines exceeding emissions thresholds still need permits. The agency told Reuters it’s now weighing changes that would give portable units more regulatory flexibility while still protecting public health. xAI, MDEQ and the EPA all declined to answer Reuters’ questions about how the turbines might affect communities of color living near the site.
The U.S. Justice Department entered the lawsuit with a June 15 filing arguing that restricting the turbines could threaten national security, since xAI’s systems support U.S. military operations, including operations tied to Iran.
Mary Rock, a senior attorney at Earthjustice representing the NAACP and the Southern Environmental Law Center, said the case could set a troubling precedent. “This sets up scenarios where the government can create sacrifice zones and tell communities they have to breathe illegal air pollution,” she said.
The dispute mirrors a 2022 study by researchers at UCLA and Columbia University, published in the journal Nature Energy, which found that communities historically subjected to redlining, where banks once denied mortgages to Black applicants, now face disproportionately high exposure to pollution from fossil fuel facilities. “Air pollution from these and other sources contributes to systemic racial disparities in chronic disease and ultimately shorter lives,” said Lara Cushing, a UCLA public health professor who co-authored the study.
The Numbers Behind the Pollution
Emails reviewed by Reuters included manufacturer emissions data for 32 of the 59 turbines, including 30 at the Southaven site. Based on that data, Reuters calculated that those 30 turbines alone could emit close to 2,500 short tons of nitrogen oxide, 4,000 short tons of carbon monoxide and 22 short tons of formaldehyde a year, assuming continuous operation at 80% capacity, the load level the EPA says gas turbines typically run at for efficiency.
Nitrogen oxides contribute to smog and respiratory inflammation, according to the American Lung Association. Carbon monoxide limits the body’s ability to absorb oxygen, and formaldehyde is a known carcinogen. The site’s potential emissions far exceed the Clean Air Act threshold of 100 short tons annually for pollutants like nitrogen oxide, the level that triggers permitting requirements.
“This is a massive amount of turbines and an unfathomable amount of air pollution,” said Southaven resident Shannon Samsa, director of the Safe and Sound Coalition. “It’s not a hypothetical that air pollution is bad for you.”
Nicholas Mailloux, a postdoctoral researcher at the University of Wisconsin-Madison who studies air quality, said the nitrogen oxide emissions calculated for roughly half the plant’s turbines would place the facility among the top 25 gas plants in the country for that pollutant, based on EPA data for actual emissions nationwide.
Who Lives Nearby
In Southaven’s Colonial Hills neighborhood, residents say the turbines run around the clock, firing off bursts of noise they compare to jet engines. Ervin Laws, a Colonial Hills resident in his 20s, said the noise wakes him up at night. “I can’t do anything about it, because he’s got more money than me,” he said, referring to Musk.
A Reuters analysis of CDC data found that in 27 of 28 census tracts within five miles of the site, spanning both Mississippi and Tennessee, estimated asthma rates exceeded their respective countywide averages. Chronic obstructive pulmonary disease rates were also higher in 24 of those tracts. Researchers commonly use a five-mile radius to identify populations likely exposed to pollution from a stationary source.
A separate Reuters analysis of Census Bureau data found that residents near the facility are disproportionately Black. Within five miles of the site in DeSoto County, Mississippi, about 46% of residents are Black, compared with 33% countywide. Across the state line in Tennessee, where residents have no voice in Mississippi’s permitting process, about 94% of residents within five miles of the facility are Black, compared with 52% in the surrounding Shelby County.
Jayajit Chakraborty, a professor at the University of California, Santa Barbara, said the Reuters findings align with existing research showing that communities of color face higher exposure to fossil fuel pollution. Shelby County and parts of DeSoto County have previously failed to meet federal ozone standards and remain under EPA-approved plans meant to keep them from falling out of compliance again. Nitrogen oxide is a key building block of ozone formation, which the EPA says can damage respiratory health.
“Given this community struggles with high asthma rates, additional NOx exposure at such high rates could exacerbate public health issues in a community that is already seeing more than its fair share of exposure to toxic air pollution,” said Victoria Nelson, an independent environmental engineer formerly with the EPA.
Sarah Gladney, 72, has watched xAI expand across the Memphis area from her home in Boxtown, a historically Black neighborhood a few miles from where the company built its first data center, Colossus 1, in 2024. “Once they got their foot in the door in Memphis, I feel like it’s going to be a continuous movement of xAI into these other communities,” she said. “It’s all about the money, and it’s not about the health or wellness of the people that live in or near these communities.”
