U.S. asks judge to dismiss NAACP air pollution suit against xAI
The Justice Department says the case could threaten a Mississippi data center powering Grok systems used by the military.
By Maya Lindqvist · Senior Technology Correspondent
3 min read
The Justice Department has asked a federal judge to throw out a Clean Air Act lawsuit accusing Elon Musk’s xAI of running gas turbines without required air permits. Federal lawyers said the case could disrupt an xAI data center in Mississippi that powers Grok systems used in military operations.
The NAACP sued xAI and its subsidiary MZX Tech in April in U.S. District Court for the Northern District of Mississippi. The group alleged that xAI was operating 27 gas turbines without an air permit at a Southaven, Mississippi, facility tied to its Colossus data center.
In a June 12 court filing, the NAACP said the number of unpermitted turbines had increased to 57 by mid-May, with two more planned. The group said the turbines supply power to the Colossus 2 data center, which supports xAI’s Grok chatbot systems.
The Justice Department argued in its filing that the Mississippi Department of Environmental Quality had concluded the turbines did not need permits. The department also said the lawsuit threatens artificial intelligence development and the power supply behind it.
Federal lawyers said Grok supports military work for the Department of War. In a declaration filed with the court, Cameron Stanley, the department’s chief digital and artificial intelligence officer, said the Grok Gov Model worked with the Maven Smart System during Operation Epic Fury, helping U.S. forces deploy more than 2,000 munitions against 2,000 targets within 96 hours.
Stanley said the Grok Gov Model has capabilities not found in other AI models. The Justice Department argued that cutting power to Grok would pose a national security risk.
Environmental group challenges federal argument
The Southern Environmental Law Center, which represents the NAACP, said the Trump administration is trying to let xAI avoid legal requirements because federal officials support the company’s operations. The group said the Justice Department did not dispute that xAI is producing pollution, and instead argued that the lawsuit should not proceed.
The SELC said citizen suits under the Clean Air Act are meant to allow communities to act when regulators do not. The group warned that the federal government’s position could weaken that enforcement tool if courts accept that the government can block community-led cases it opposes.
The NAACP’s lawsuit relies on a Clean Air Act provision allowing citizen suits against anyone who constructs or proposes to construct a new or modified major emitting facility without a permit. In its June filing, the NAACP argued that state findings do not bar citizen enforcement under the federal law.
Mississippi Gov. Tate Reeves said in a letter filed in the case that state regulators approved permits in March 2026 for xAI to build several permanent gas turbines. Reeves said the state also allowed xAI to use trailer-mounted turbines temporarily until the permanent equipment is built, and that regulators classified those temporary units as mobile sources not subject to Clean Air Act permitting.
The Justice Department also cited Mississippi’s position that shutting down the turbines would harm the state’s economy and upset the Clean Air Act’s federal-state enforcement balance.
The NAACP says the turbines threaten residents in nearby communities with large Black populations. The group said uncontrolled emissions could release nitrogen oxides at levels far above what the Clean Air Act allows, increasing risks tied to heart disease, lung disease and premature death.
The NAACP is asking the court to permanently stop xAI from operating the turbines, impose civil penalties of up to $124,426 per day, and order reimbursement of its costs and attorneys’ fees.
This story draws on original reporting from Ars Technica.