Energy Services | Industrywide Issues | MarkWest Energy | Pennsylvania | Processing Plants | Regulation | Washington County
PA DEP Issues Permit for Expansion of MarkWest Harmon Creek Plant
The Pennsylvania Department of Environmental Protection issued an air quality permit on May 18, 2026, to MarkWest Liberty Midstream, authorizing the expansion of its Harmon Creek Natural Gas Processing Plant in Washington County. The MarkWest name is still used, although the company is now MPLX. The DEP permit approval allows the addition of a third cryogenic plant and a second de-ethanization plant. A number of Big Green groups colluded in an attempt to block the permits, but their demands were ignored. Read More “PA DEP Issues Permit for Expansion of MarkWest Harmon Creek Plant”
In March 2025, the Wall Street Journal reported that Shell is “exploring a potential sale of its chemicals assets in Europe and the U.S.,” which includes the Monaca (Beaver County, PA) ethane cracker complex (see 
The Pennsylvania Department of Environmental Protection (DEP) has extended three temporary air permits for the Shell ethane cracker plant in Monaca, PA, which would have expired on April 28, 2026. The DEP did the same thing in May 2024 (see 
Yesterday, Shell’s chemical division reported a $66 million fourth-quarter loss, driven by weak margins and operational hurdles at its $14 billion Beaver County ethane cracker plant complex. Shell CEO Wael Sawan acknowledged the chemicals business is underperforming, making a turnaround a “top priority” for 2026. Although Shell is exploring a sale or joint venture for the Monaca facility due to its geographic isolation and high costs, no specific updates were shared during the latest earnings call. 
Two days ago, MDN brought you the news confirming that Shell is looking to sell all or part of its Beaver County, PA, ethane cracker plant operation (see 
Last November, MDN brought you the great news that MPLX (aka MarkWest Energy) would file to build an expansion at its existing Harmon Creek facility in Smith Township, Washington County, PA (see 
Marathon Petroleum’s MPLX, formerly MarkWest, operates five complexes in the Marcellus shale. One of the five is the Bluestone Complex in Butler County, PA. Bluestone gathers 200 million cubic feet per day (MMcf/d) of natural gas. Bluestone processes 400 MMcf/d of natural gas, separating methane from other hydrocarbons. The facility then further separates ethane (C2H6) from other NGLs like propane and butane in a process called C2+ fractionation—producing some 81,000 barrels per day. Yesterday, MPLX announced that the Bluestone plant has become the only U.S. natural gas processing facility to achieve the EPA’s ENERGY STAR Challenge for Industry. 
This is your friendly (somewhat snarky) semi-regular reminder from MDN that the PTT ethane cracker project in Ohio is dead (see 
In late 2015, MPLX (i.e., Marathon Petroleum) bought out and merged in the Utica Shale’s premier midstream company, MarkWest Energy, for $15 billion (see 
In May 2023, two radicalized Big Green groups—the Environmental Integrity Project (based in D.C.) and the Clean Air Council (based in Philadelphia)—filed a lawsuit against the Shell Polymers Monaca Plant (ethane cracker plant in Beaver County, PA), claiming the plant has repeatedly violated federal air pollution limits (see 
Last Friday, RBN Energy published a blog post declaring that the Shell ethane cracker in Monaca (Beaver County), PA, is now “firing on all cylinders.” The post retrospectively covers the project’s history, from construction through recent problems as the plant was commissioned to the present day. We learned something interesting: Shell, a petrochemical giant and owner of other cracker plants producing various products, had exited the plastic pellets business years ago. The Monaca cracker is Shell reentering that market.