The city of Walnut filed court papers Wednesday challenging the City of Industry's approval of a stadium complex.
The petition filed in Los Angeles Superior Court alleges the project, which would be built near the interchange of the Pomona (60) and Orange (57) freeways, was given the green light without an adequate environmental impact report.
Industry city officials hope to lure a National Football League team to the site.
As approved, the stadium would exacerbate unhealthful air quality and traffic congestion in the region while diminishing the quality of life in Walnut, according to the complaint.
Industry City Manager Kevin Radecki was not immediately available for comment on the petition, which also names Majestic Realty Co. and its president, Edward Roski Jr., as defendants.
Project proponents maintain a stadium would spur economic growth in the region, while Walnut city officials maintain that their community and others, including Diamond Bar, would have to endure significantly more traffic, noise and air pollution.
The project would also force Walnut to pay more to provide traffic improvements, fire service and police protection, according to the city's petition challenging the adequacy of the EIR.