A group of Alhambra residents is suing the city in an attempt to block a controversial development project that will bring a Lowe’s home improvement store and two six-story office towers to a 12-acre lot on South Fremont Avenue.

Neighborhood activist group Grassroots Alhambra filed the lawsuit Monday in the Los Angeles Superior Court, as the Pasadena Star News reports. The suit alleges that the project did not undergo sufficient environmental review before being approved by the city’s planning department in January.

According to a press release from the group, the project, which also includes a six-floor parking structure, would be “located in one of the most congested and contaminated areas in the city of Alhambra.”

The contamination part of that statement refers to the possibility that toxic materials could be left over from a manufacturing plant that previously occupied the project site. Residents maintained this position in an appeal of the project rejected by the city council in February.

The project is being developed by the Charles Company, which is also working to redevelop the long-abandoned Hawthorne Mall into an outdoor shopping complex.

Dr. Ron Sahu, a leader of Grassroots Alhambra, said the group has nothing against the developer—or development in general. “We are simply against the illegal manner in which the City of Alhambra sought to approve the project,” he maintained.