New York state’s denial of a Clean Water Act (CWA) permit for the proposed Constitution Pipeline has killed any chance of the project meeting it’s scheduled Dec. 2, 2018 construction deadline, the company said in a filing at FERC Monday.

Constitution Pipeline Co. LLC asked for an extension until Dec. 2, 2020 for construction of the project.

Constitution filed at the Federal Energy Regulatory Commission for its project five years ago, and received a FERC certificate authorizing the project in 2014. The 125-mile pipeline would carry Marcellus Shale gas from Susquehanna County, PA, interconnecting with the Iroquois Gas Transmission and Tennessee Gas Pipeline (TGP) systems in Schoharie County, NY.

Besides Williams, the project is backed by Cabot Oil & Gas Corp., Piedmont Natural Gas Co. Inc. and WGL Holdings Inc.

The project’s sponsors have battled the New York State Department of Environmental Conservation (DEC) since 2016, when after nearly three years of regulatory review the agency denied the pipeline’s application for a section 401 water quality certificate (WQC) required under the CWA. Eight weeks ago, the U.S. Supreme Court denied a petition filed by Constitution to challenge New York’s regulatory authority and let stand an appeals court ruling that upheld the state’s decision to deny the project a WQC.

The DEC denial was mainly related to a disagreement over trenchless crossings and the agency’s contention that it didn’t have enough information to determine the project’s environmental impact.

Constitution had argued that without a ruling from the Supreme Court, states could use their authority under the CWA to undermine interstate natural gas pipeline development. Monday’s denial, however, is not the last gasp for the project.

Earlier this year, FERC denied Constitution’s petition for a declaratory order that the DEC waived its authority when it failed to issue a WQC within a reasonable period of time. Constitution subsequently filed a request for rehearing at FERC, asking the Commissioners to reconsider their decision upholding New York’s authority.

DEC’s denial, Constitution said in its filing at FERC Monday, “continues to delay the project, and, as a result, Constitution will not be able to complete construction of the project by Dec. 2, 2018. Accordingly, Constitution requires, and hereby requests, an extension of time to construct the project.”

Constitution said it has “worked in good faith and has uses its best efforts to obtain all of the approvals required for construction of the project,” including providing “a multitude of detailed technical submissions” to the DEC in its attempts to obtain a WQC, and it “continues to diligently pursue all available legal remedies” to obtain the permit. All other required federal permits for the project are in hand, Constitution said.