Constitution Pipeline Co. LLC is refusing to back down in its saga to get its beleaguered 124-mile natural gas pipeline approved and has petitioned the U.S. Supreme Court to review an appeals court ruling in August against the project.

The Supreme Court has been asked to review a ruling by the U.S. Court of Appeals for the Second Circuit. Constitution posted a statement on its website on Tuesday notifying the public of its petition. The move came less than a week after what appeared to be a major setback for the Constitution project when FERC refused to waive New York’s regulatory authority.

Constitution received a Federal Energy Regulatory Commission certificate authorizing the project in 2014. However, sponsors have battled the New York State Department of Environmental Conservation (DEC) since 2016. After nearly three years of regulatory review, the agency denied the pipeline’s section 401 water quality certificate (WQC) required under the Clean Water Act (CWA).

“Without a ruling from the U.S. Supreme Court, there is a serious risk that states will use the Second Circuit’s ruling to abuse their narrowly circumscribed CWA Section 401 authority in their efforts to frustrate interstate natural gas pipeline development at the expense of vital national interests,” Constitution’s sponsors said.

The project has bounced through the regulatory and legal process. After the DEC denied its WQC application, mainly over a disagreement about trenchless crossings and the agency’s contention that it didn’t have enough information to determine the environmental projects, the company petitioned the Second Circuit to review the decision.

The appeals court denied the challenge, with a three-judge panel ruling that the DEC is entitled to its regulatory review under relevant federal laws. Constitution later petitioned the court for a rehearing of the case en banc, which was also denied.

Last week, FERC denied the company’s petition for declaratory order that the DEC waived its authority when it failed to issue a WQC within a reasonable period of time. FERC found that the DEC did not fail to act within the one-year timeframe required under the CWA because Constitution withdrew and resubmitted its application twice, resetting the deadline each time.

Constitution argued in its petition to the Supreme Court that the Second Circuit’s decision conflicts with the decisions of the high court and other federal courts of appeals.

New York has similarly denied a WQC for National Fuel Gas Co.’s Northern Access expansion project and Millennium Pipeline Co. LLC’s Valley Lateral project. While Valley Lateral is moving forward after a favorable ruling from FERC, Northern Access remains bogged down in court.

The industry has continued to argue through legal proceedings that New York’s stance on the projects violates the federal/state balance struck by Congress in the Natural Gas Act’s process for approving gas pipeline projects. The industry has also expressed concerns about what New York’s stance against the pipelines could mean for interstate commerce, as environmentalists have been emboldened by the WQC denials and have called on other states to follow suit.

Constitution said Tuesday the “federally-approved project has been unjustly prohibited from construction.” The project would move more gas from northeast Pennsylvania to New York and the Northeast. It is backed by Williams, Cabot Oil & Gas Corp., Piedmont Natural Gas Co. Inc. and WGL Holdings Inc.