Rahul Somvanshi
Families in Southaven, Mississippi, and South Memphis have spent nearly two years breathing air shaped by a power plant nobody approved. Elon Musk’s AI company, xAI, built the facility to run its Colossus 2 data center. It kept adding turbines even after regulators and civil rights lawyers said the project broke federal clean air law. The dispute now pulls in the Department of Justice itself.
xAI and its energy subsidiary, MZX Tech, operate up to 33 gas-fired turbines at a site in Southaven. The site sits just across the Mississippi state line from the Colossus 2 data center in Memphis, Tennessee. The turbines power the AI supercomputer cluster known as Colossus, which trains models for Musk’s Grok chatbot. According to a May 2026 court filing from Earthjustice, the 33 turbines could emit 2,508 tons of smog-forming nitrogen oxides a year. They could also release 236 tons of fine particulate matter, 837 tons of carbon monoxide, and 25 tons of formaldehyde annually. The NAACP calls the facility a likely candidate for the largest industrial source of nitrogen oxide pollution in greater Memphis.
That pollution lands in a region already struggling to meet federal smog standards. The American Lung Association gave both Shelby County, Tennessee, and DeSoto County, Mississippi, an F grade for ozone pollution. Adding thousands of tons of nitrogen oxides and particulate matter pushes air quality further from compliance. The added risk falls on residents near the turbines. Many live in historically Black neighborhoods already burdened by industrial pollution, a pattern documented across other AI data center fights nationwide.
How xAI avoided a permit for two years
xAI began installing gas turbines at the Southaven site shortly after Colossus 1 launched in 2024. It never applied for a Clean Air Act permit before switching them on. The Southern Environmental Law Center reported that the company ran 27 turbines capable of generating up to 495 megawatts. That output roughly matches a conventional power plant, yet xAI skipped the pollution controls and public comment process the law requires. In February 2026, the NAACP sent xAI a formal notice of intent to sue. The notice warned that major pollution sources must obtain permits before construction or operation begins. xAI’s reported response was to bring six more turbines online. That raised the total to 33 just as the NAACP’s lawsuit moved forward in court.
The company’s power demands kept climbing even as state regulators tried to catch up. That scramble is also playing out at other Colossus-scale facilities Musk has pushed through Memphis. In March 2026, the Mississippi Department of Environmental Quality issued an air permit covering 41 turbines at the site. The Southern Environmental Law Center called the decision a rubber stamp. The hearing was held on Election Day, nearly three hours from the affected communities. The agency closed the public comment period just three weeks before approving the permit. SELC and community groups have since appealed. They argue the permit understates real emissions and ignores months of turbines xAI already ran illegally.
DOJ steps in citing national security
The case escalated in June 2026 when the Department of Justice intervened on xAI’s side. It did not join as a defendant but as an outside voice urging the court to dismiss the NAACP’s lawsuit. Federal attorneys argued that the Pentagon’s interest in AI capability made continued turbine operation a matter of national, economic, and energy security. That is an unusual argument for the government to make in a private pollution dispute. The NAACP, represented by SELC and Earthjustice, pushed back with a request for a preliminary injunction. It asks the court to force an immediate shutdown of the unpermitted turbines while the lawsuit proceeds. The filing points out that six of the newest turbines rank among the largest and dirtiest machines on site.
Readers often ask: is it legal to run a power plant without a permit if regulators later approve a bigger one covering the same equipment. The answer under the Clean Air Act is no. Permits must be obtained before construction and operation begin. A later, broader permit does not retroactively excuse months of unlawful emissions. That is why the NAACP’s suit still targets the earlier unpermitted turbines directly.
By August 2026, under pressure from the lawsuit and local opposition, SpaceX agreed to phase out the temporary turbines by 2027. SpaceX now owns xAI and plans to build a permanent gas plant to replace the turbines. That commitment addresses the long-term power source. It does not resolve the pending claims over nearly two years of pollution residents say they already absorbed. Attorneys for the NAACP argue the 2027 timeline still leaves communities breathing unpermitted exhaust for another full year.
What makes this dispute unusual is how openly federal agencies have weighed AI infrastructure against environmental law in the same case. A power plant dispute rarely draws a Justice Department brief invoking Pentagon interests. That intervention shows how much weight Washington now places on keeping AI data centers running. That weight holds even when the power source has never passed a basic permit review. The fight also lands amid a national debate over who absorbs the rising cost of powering AI infrastructure. That debate spans grid upgrades and the generators data centers now lean on.
xAI’s Southaven turbines illustrate a pattern across the data center boom. Companies race to power AI clusters before securing required permits, then defend the gap in federal court once communities notice. The NAACP’s Clean Air Act lawsuit, the DOJ’s intervention, and SpaceX’s 2027 phase-out commitment all remain unresolved. Memphis and Southaven residents are left waiting to see whether the courts or the company’s own timeline settles the fight first.
