The U.S. Court of Appeals for the Third Circuit has rejected a challenge filed by environmental groups against the Atlantic Sunrise project’s Section 401 Water Quality Certification (WQC) issued under the Clean Water Act by Pennsylvania.

The combined case pitted the Delaware Riverkeeper Network (DRN), Lancaster Against Pipelines and the Sierra Club against the Pennsylvania Department of Environmental Protection (DEP). The groups argued that the agency improperly issued the WQC. The court’s decision to reject their argument comes as the 1.7 Bcf/d project is preparing to enter full service.

DRN, which filed its lawsuit in May 2016, and co-petitioners argued that the DEP failed to apply appropriate state standards for determining whether the WQC was proper and said the agency instead issued the certification contingent upon future state permitting for the project. The groups also argued that the agency issued the WQC without considering the ability of Transcontinental Gas Pipe Line Co. LLC (Transco) to comply with necessary state permits and a rare environmental rights amendment in the Pennsylvania constitution.

The court rejected the arguments in what Delaware Riverkeeper Maya van Rossum said was another effort by federal judges to twist “themselves into pretzels to find ways to deny” citizens’ rights.

About 550 MMcf/d of capacity on the project has already been placed into service. Last month, Transco asked FERC for authorization to begin full service on the remaining parts of the pipeline by Monday (Sept. 10). Atlantic Sunrise would create an additional path for constrained gas in northeast Pennsylvania to reach markets in the Mid-Atlantic and Southeast via the Transco mainline that runs along the Atlantic seaboard.

The Federal Energy Regulatory Commission issued a certificate for the project in February 2017, and greenfield construction started late last year. The project has faced several legal challenges along the way. It was briefly halted late last year after the U.S. Court of Appeals for the District of Columbia stayed construction to issue an emergency motion filed by environmental groups. The stay was lifted days later and construction was allowed to resume.