A federal judge ruled on Oct. 30 that the gas turbines powering Elon Musk’s xAI data center in Southaven, Mississippi, are not exempt from Clean Air Act permits. Eleven days later, Mississippi’s Environmental Quality Permit Board upheld the state’s air permit for the plant’s 41 turbines, over the objections of the NAACP.
The two decisions came from different bodies and settle different questions. Together they show how the fight is going for the Black residents of South Memphis, who have lived beside the company’s turbines since 2024. The NAACP sued in April on behalf of communities in South Memphis and north Mississippi. Boxtown, the predominantly Black neighborhood closest to xAI’s Memphis site, has reported worsening asthma, in a county that the American Lung Association grades “F” for air quality and where more children are hospitalized for asthma than anywhere else in Tennessee.
In the federal case, Chief U.S. District Judge Debra M. Brown rejected xAI’s argument that its turbines were “mobile sources” outside the permit rules. “The Plant is not a ‘mobile source,'” her order says. She also held that citizen suits under the Clean Air Act are constitutional. Two weeks earlier she had turned down a Trump Justice Department motion to dismiss the case, writing that the court “does not consider the United States’ national security concerns relevant.”
The Southern Environmental Law Center and Earthjustice, which represent the NAACP, say the Southaven site spans 114 acres and emits more than 5,000 tons of nitrogen oxides, 400 tons of fine particulate matter and 47 tons of formaldehyde a year. Those are the plaintiffs’ figures, not the court’s. The NAACP’s request for a preliminary injunction that would halt the turbines is still pending.
The permit board’s Nov. 10 decision went the other way. The Southern Environmental Law Center had challenged the March permit issued to the company’s subsidiary MZX Tech on behalf of the NAACP, the Safe and Sound Coalition and Young Gifted & Green, arguing that the pollution modeling understated nearby sources and that emissions should be offset elsewhere. Staff at the Mississippi Department of Environmental Quality said the project could meet state and federal requirements and that offset rules did not apply because the area meets air-quality standards.
The company, now part of SpaceX as SpaceXAI, has said it will phase out its temporary units once permanent ones are permitted. The state agency has also issued enforcement notices carrying about $6.1 million in potential penalties across three Southaven-area sites.
A regulator that had treated the turbines as exempt has now been told by a federal judge that they were not, and it still approved the plant’s next phase. People in Boxtown have breathed the exhaust of a plant that ran without permits for more than a year, and they should not have to wait for a second ruling to learn whether anyone pays for it. Brown can decide the injunction request at any time, and the NAACP’s Clean Air Act case moves on toward penalties.
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