The Colossus data center, run by Xai, outside of Memphis, faces a lawsuit to operate a fleet of natural gas turbines without permission.
“In the past year, Xai has installed and operated at least 35 combustion turbines and other air pollution sources of air pollution without obtaining air permits for the necessary construction or operation,” the Southern Environmental Law Centre (SELC) wrote in a letter to Xai.
The Legal Group submitted a letter on behalf of the NAACP. It serves as a notice of intent to sue Xai for violations of the Clean Air Act. The law requires organizations to file such letters 60 days prior to filing the lawsuit.
Gas turbines can release more than 2,000 tons of NOX per year, a group of chemicals that contribute to smog.
Memphis already had some of the worst air quality in the region,” Selc notes. “In 2024, Memphis was considered the country's asthma capital by the American Asthma and Allergy Foundation due to its high mortality from asthma visits and asthma.”
SELC alleges that Xai failed to obtain the necessary permits by both federal and local regulators before installing the generator. They also claim that the company did not operate them with proper air pollution control. At one point, Xai had enough turbines to generate 421 megawatts of power.
Last summer, the Shelby County Health Department, which oversees local air pollution compliance, told reporters that Xai's turbines are exempt from permits, but Schd did not publicly disclose what Xai is operating on its site or the legal basis for such exemptions,” Selc said.
To determine what's going on at the Colossus site, Selc paid an aerial photographer in March to capture images of the facility. The photo reveals that Xai had installed 35 turbines around the data center at the time. Thermal images taken about a month later showed at least 33 were operating, SELC said.
After these images were taken, the Greater Memphis office, the local economic development agency, said Xai had removed some of the turbines.
“The temporary natural gas turbines that were used to power Phase I GPUs prior to the grid connection have now been de-mobilized and will be removed from the site in the next two months,” the Memphis office said. The organization added that “about half of the operating turbine remains” until the second substation was completed, and once the substation was completed, the turbine began to act as a backup.
However, the flight on June 15 showed at least 26 turbines remain, including three new turbines installed since the April flight. The total production capacity was around 407 megawatts, only 14 megawatts from its previous amount.
“With very few exceptions – not applicable here, Tennessee standards and other new sources of air pollutants must obtain pre-construction approval in the form of air permits and permits to operate and release pollutants,” SELC said.