The Delaware River Basin Commission on Thursday approved a permanent ban on hydraulic fracturing of natural gas wells along the river, doubling down in the face of new legal challenges.

The DRBC’s vote maintains the status quo — it formally affirms a drilling moratorium imposed in 2010 by the commission, the interstate agency that manages water use in the vast Delaware watershed. But environmentalists hailed the frack ban as historic.

The commission said it had the authority to ban fracking in order to control future pollution, protect the public health, and preserve the waters in the Delaware River Basin. For more than debate, environmental activists have rallied substantial public opposition in the basin to pressure the commission to enact the ban.

The formal ban came a month after a federal judge set an October trial date to hear a challenge from landowners to the drilling moratorium, which is now a permanent ban. Pennsylvania Republican lawmakers, along with Damascus Township in Wayne County, also filed a separate federal legal action last month alleging that the moratorium illegally usurps state legislators’ authority to govern natural resources.

Representatives of the governors of four states that are drained by the river — Pennsylvania, New Jersey, Delaware and New York, all governed by Democrats — voted in favor of the ban. The fifth commission member, a federal government representative from the U.S. Army Corps of Engineers, abstained because he said the corps needed additional time to “coordinate” with the new Biden administration.

The new DRBC rules prohibit high-volume hydraulic fracturing for fossil fuels within the 13,539-square-mile basin. The commission put off a decision on whether to allow the treatment of wastewater from fracking outside the basin. It also postponed a decision on whether to allow water from the Delaware basin to be used in fracking outside the basin.

Fracking involves the injection of water and chemicals under high pressure deep underground to unlock natural gas trapped in tight geologic formations, such as shale. The process has unleashed a fossil fuel boon of cheap energy, but it has attracted a backlash from environmentalists because of associated health and environmental harms.

The DRBC imposed a fracking moratorium in 2010 but never finalized drilling regulations. In 2017, the commission changed direction and moved to draft regulations to formally ban fracking in the basin. After a series of public hearings in 2018, the commission delayed a decision until Thursday.

The ban effectively impacts activity only in Pennsylvania, because New Jersey and Delaware have no natural gas that can be developed and New York, whose southern tier adjoins some of Pennsylvania’s richest shale fields, has banned fracking statewide. In Pennsylvania, hydraulic fracturing is conducted extensively and legally across a broad swath of the state underlain by Marcellus and Utica shale formations, and has transformed the state into the nation’s second-largest gas producer.

New Jersey Gov. Phil Murphy, in a statement read by a deputy, said Thursday that fracking poses significant risks to the water resources of the Delaware River Basin, and prohibiting the activity “is vital to preserving our region’s recreational and natural resources and ecology.”

Patrick McDonnell, Pennsylvania’s secretary of environmental protection, read a statement from Gov. Tom Wolf that said he cast the state’s vote in favor of the ban “after careful analysis and consideration of the unique geographic, geologic and hydrologic characteristics” of the river basin. He also noted that the ban fulfilled a Wolf 2014 campaign pledge.

McDonnell said the commission was acting under authority of the Delaware River Basin Compact, the 1961 interstate agreement to manage water resources in the Delaware basin. That’s an important distinction because the lawsuits challenging the DRBC’s actions allege that the commission is acting beyond its legal authority by banning a practice that is governed exclusively by Pennsylvania law.

In the lawsuit last month, State Sens. Gene Yaw (R., Lycoming) and Lisa Baker (R., Luzerne) and the Pennsylvania Republican Caucus alleged that the moratorium — now a ban — undermines the General Assembly’s prerogative to make laws managing the state’s resources. They also said that the DRBC’s action amounts to an illegal taking of property from Pennsylvania owners of mineral rights and from taxing authorities.

Matthew H. Haverstick, a Philadelphia lawyer who filed the suit on behalf of the Republican caucus, said the DRBC’s action Thursday does not alter the underlying argument in the lawsuit.

“It’s still a taking that was never authorized by Pennsylvania under the compact,” said Haverstick, a partner with the Kleinbard LLC law firm. “So the core issues from my standpoint remain.”

In a separate suit heading to trial in October in U.S. District Court in Scranton, a Wayne County landowner group alleges that the DRBC doesn’t have jurisdiction over gas drilling. The suit alleges that the DRBC regulates no other land use or industry like gas drilling, and points to the experience in the neighboring Susquehanna River basin, where it said a decade of drilling has not caused “discernible impacts” on water quality.

Business and the gas industry advocates denounced the DRBC’s ban as an overreach. The American Petroleum Institute Pennsylvania said the commission’s decision “ignores a robust regulatory system and strict industry standards that ensure the environment, public health and local communities are protected.”

Environmentalists, citing the dangers of drilling and the climate impacts of more fossil fuel production, lauded the commission’s actions and dismissed the lawsuits from “extremist” opponents as frivolous.

“We have been calling for a decision for years now and been making the point that really the time is now,” said Maya van Rossum, the head of the Delaware Riverkeeper Network, an advocacy group that has intervened in the lawsuits.

National Parks Conservation Association that the fracking ban would spare the Delaware Water Gap and the Upper Delaware Scenic and Recreational River areas, saying the parks attracted three million visitors in 2019 and generated nearly $130 million in economic activity.

“It is imperative that we protect our parks, our resources, and the people who love and depend on them from the devastating environmental impacts of fracking,” said Halle Van der Gaag, the association’s senior manager for Pennsylvania and Delaware programs.

Food and Water Watch, an advocacy organization that has pushed for a nationwide ban on fracking, said it was disappointed the Biden administration abstained. “Biden should listen to communities and science and support a ban on fracking everywhere,” the organization’s executive director, Wenonah Hauter, said in a statement.

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