A celebratory car parade is planned for Saturday, but even the opponents of a natural gas compressor station in Weymouth say a new court ruling in their favor will not stop project construction.

"Although Enbridge may continue constructing, they cannot operate this facility without the air quality permit," Fore River Residents Against the Compressor Station wrote in an email to its supporters Thursday morning. "And, it gives us more room to fight to stop it from ever operating."

Federal Appeals Court Judge William Kayatta on Wednesday vacated an air permit Massachusetts regulators awarded to the controversial natural gas project, which has drawn widespread opposition, ruling that the state did not sufficiently assess the technology set to be used for emissions reductions.

Kayatta's decision also includes components that are favorable to Enbridge and the Department of Environmental Protection.

"The petitioners raise a slew of arguments that DEP violated the Massachusetts CAA [Clean Air Act] and related laws and regulations," he wrote. "Because we find that DEP did not follow its own established procedures for assessing whether an electric motor was the Best Available Control Technology (BACT), we vacate the air permit and remand to the agency to redo that analysis. We resolve the remaining issues in favor of DEP."

In an email Wednesday night, attorney Mike Hayden of Morrison Mahoney LLP, who has been working with the gas project opponents, called the federal court ruling "incredible and uplifting news" and said he would separately craft a more detailed review and analysis of the decision.

The car parade is being planned for Saturday morning.