Elon Musk’s artificial intelligence company xAI has placed 59 natural gas turbines into operation for its Colossus 2 data center project in Tennessee without first obtaining the required federal clean air permits, according to communications between company representatives and government regulators.
The potential pollution output from those turbines far surpasses the level that would trigger a mandatory federal permit — and the emissions would be released in areas where predominantly Black communities are already estimated to suffer from unusually high rates of lung disease. That finding comes from a Reuters analysis drawing on government data and regulatory correspondence.
The number of unpermitted turbines uncovered is roughly twice what xAI has publicly admitted. The company previously stated it was running 27 unpermitted turbines for Colossus 2 as of January and has maintained that permits are not legally required. At least 57 of the 59 turbines are situated in Mississippi, just across the state border from the Tennessee data center.
These turbines are part of a broader national trend of off-grid power plants being built for data centers, where local authorities frequently approve projects in weeks or months — bypassing the years of environmental review and public input normally required for power generation facilities that connect to the electrical grid.
Mississippi regulators issued a permit in March for permanent turbines at Colossus 2, authorizing construction of 41 gas-fired turbines. That approval came just 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 analysis, noted the scale of the installation is extraordinary. “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 regulatory communications reviewed by Reuters show xAI — now owned by SpaceX, which belongs to trillionaire Musk — has placed 57 off-grid turbines in Southaven, Mississippi, just over the state line from its Colossus 2 facility in Memphis. That Memphis location supports the Grok chatbot and other AI systems. Two additional unpermitted turbines were installed at a separate location, though Reuters was unable to determine where.
The documents, obtained through a public records request, included emails between Trinity Consultants — representing xAI and its subsidiary MZX Tech — and the Mississippi Department of Environmental Quality. xAI did not respond to a request for comment.
Civil rights organizations including the NAACP and the Southern Environmental Law Center filed a lawsuit in April seeking to stop the turbines from running, arguing the emissions fall under the federal Clean Air Act and cannot legally be produced without permits. The groups say the turbines are fouling the air near historically Black homes, schools, and churches.
“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.”
Obtaining a Clean Air Act permit would have subjected xAI’s project to extensive public scrutiny and could have taken years. Mississippi environmental regulators and xAI have argued in court that the turbines are exempt because they are classified as “mobile” and are intended to operate on-site for less than a year.
“MDEQ has determined that portable/temporary turbines do not require an air permit,” the Mississippi Department of Environmental Quality said in a statement.
The U.S. Environmental Protection Agency stated in January 2026 that even temporary turbines that exceed emissions thresholds must obtain permits. However, the agency told Reuters it is considering changes that would allow “regulatory flexibilities” for portable units while still protecting public health.
The U.S. Justice Department entered the legal dispute in a June 15 filing, arguing that curtailing the turbines could endanger national security because xAI’s systems support U.S. military operations, including those involving Iran.
“This sets up scenarios where the government can create sacrifice zones and tell communities they have to breathe illegal air pollution,” said Mary Rock, a senior attorney for Earthjustice, which is representing the NAACP and the Southern Environmental Law Center.
A Reuters analysis of the manufacturer emissions profiles for 30 of the Southaven turbines found they could collectively release nearly 2,500 short tons of nitrogen oxide, 4,000 short tons of carbon monoxide, and 22 short tons of formaldehyde each year — assuming they run continuously at 80% capacity, a typical operating level according to the EPA. Nitrogen oxides contribute to smog and respiratory inflammation, carbon monoxide deprives the body of oxygen, and formaldehyde is a known carcinogen.
Those figures far exceed the Clean Air Act threshold of 100 short tons annually that triggers the permitting requirement for pollutants such as nitrogen oxide.
Nicholas Mailloux, a postdoctoral researcher at the University of Wisconsin-Madison who studies air quality and the health benefits of clean energy, said the nitrogen oxide emissions calculated for roughly half the plant’s turbines would place it “up there with some of the heaviest polluting natural gas power plants across the entire country” — on par with the top 25 U.S. gas plants for nitrogen oxide output, based on EPA data.
“This is a massive amount of turbines and an unfathomable amount of air pollution,” said Shannon Samsa, a Southaven resident. “It’s not a hypothetical,” she added, “that air pollution is bad for you.”
In the Colonial Hills neighborhood of Southaven, residents say the turbines run constantly, producing loud bursts of noise they compare to jet engines. Ervin Laws, a Colonial Hills resident in his 20s, said the noise disturbs his sleep. “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 — covering areas in both Mississippi and Tennessee — estimated asthma rates were higher than countywide averages. In 24 of those tracts, rates of chronic obstructive pulmonary disease were also elevated.
Census Bureau data further showed that residents living near the facility are disproportionately Black. Within five miles of the turbines in DeSoto County, Mississippi, approximately 46% of residents are Black, compared to 33% countywide. Across the state line in Tennessee, roughly 94% of residents within that same radius are Black, versus 52% in the surrounding county.
Shelby County in Tennessee and portions of DeSoto County in Mississippi have also previously failed to meet federal ozone standards and remain under EPA-approved plans to prevent future violations. Nitrogen oxide is a key factor in ozone formation, which the EPA links to respiratory harm.
“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 and former EPA employee.
Sarah Gladney, 72, lives in the historically Black Boxtown neighborhood, a few miles from where xAI built its Colossus 1 data center in 2024. She has watched the company’s footprint expand rapidly. “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.”
Lara Cushing, a public health professor at UCLA who co-authored a 2022 study on pollution burdens in historically redlined communities, told Reuters: “Air pollution from these and other sources contributes to systemic racial disparities in chronic disease and ultimately shorter lives.”
