The Department of Justice has filed a memorandum in support of xAI in a lawsuit seeking to shut down the company's unpermitted natural gas turbines near its Memphis data centers in Mississippi. The move marks an escalation in a dispute that began when the NAACP filed suit in April, represented by the Southern Environmental Law Center.
The DOJ's reasoning centers on national security. In its filing, the Justice Department argued that a ruling against xAI would undermine "American national, economic, and energy security by seeking to shut off the power supply for artificial-intelligence innovation that supports the Department of War's military operations." The memorandum specifically names Grok as one of four AI models supporting "mission-critical operations," including recent military strikes in Iran.
The core dispute turns on a technical distinction. xAI has installed 57 natural gas turbines mounted on trailers at its Colossus and Colossus 2 data centers. The company argues that because the turbines remain on trailers, they are exempt from Mississippi air pollution regulations for one year. However, the Southern Environmental Law Center contends that federal law classifies trailer-mounted turbines as stationary equipment when used in this manner, making them subject to regulation regardless of their mobility.
The NAACP's lawsuit reflects mounting concerns about air quality in the region. According to the suit, since xAI's data centers went online, the number of turbines has more than doubled—from roughly 25 to 57—and air pollution has worsened correspondingly. Three major pollutants have increased: particulate matter 2.5 microns or smaller (PM2.5), formaldehyde, and nitrogen oxides (NOx). Health research links all three to serious conditions. PM2.5 has been associated with stroke and Alzheimer's disease; formaldehyde increases cancer risk; and both PM2.5 and NOx are linked to asthma and cardiovascular disease. The NAACP notes that the region was already among the most polluted in the country before the data centers began operations.
The dispute is likely to intensify. In its IPO filing, SpaceX disclosed that it plans to purchase $2.8 billion worth of gas turbines over the next three years to power its AI data centers. At least $2 billion of that allocation is earmarked specifically for mobile gas turbines. The NAACP's lawsuit and the DOJ's response thus represent an opening chapter in a broader infrastructure and environmental debate around the power demands of large-scale AI operations.