Sunoco’s Mariner East 2 pipeline in Pennsylvania, United States

A "grandfathered" law enables pipeline expansion of highly volatile gas liquids coming from Marcellus and Utica shale through high population areas on their way to Europe.


The United States has about 200 million miles of natural gas transmission pipelines, many of which are buried beneath the ground nearby residential areas, schools and cities. The US has increased its demand for natural gas power generation as prices plummeted due to new exploitation of domestic natural gas in the last decade or so; now gas accounts for 1/3 of US electric power generation [11]. The Federal Energy Regulatory Commission, which approves interstate pipelines has only denied two such proposals in the past 30 years, which demonstrates a relative ease of development of pipelines in the current political context of the United States [11]. This ease should be questioned given that the past decades malfunctions and explosions stemming from natural gas pipelines have killed more than 300 people and injured or caused health problems for many more [1].

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Basic Data
NameSunoco’s Mariner East 2 pipeline in Pennsylvania, United States
CountryUnited States of America
ProvincePipeline from Western to Eastern Pennsylvania
SiteMarcus Hook, PA
Accuracy of LocationMEDIUM regional level
Source of Conflict
Type of Conflict (1st level)Fossil Fuels and Climate Justice/Energy
Type of Conflict (2nd level)Oil and gas exploration and extraction
Shale gas fracking
Transport infrastructure networks (roads, railways, hydroways, canals and pipelines)
Specific CommoditiesLiquid natural gases: propane, ethane, and butane
Natural Gas
Project Details and Actors
Project DetailsThe Mariner East Project is a 300-mile long pipeline that will be built primarily upon the existing pipeline infrastructure (50-foot easements) of the Sunoco pipeline, across the state of Pennsylvania. The original pipeline was established in the 1930s by Sunoco for the transport of refined petroleum from the refinery in Marcus Hook to western locations in Pennsylvania and other states. Pipeline was defined it as a utility, giving it eminent domain upon construction.

In 2012, Sunoco was purchased by Energy Transfer Partners L.P. and the 80-year-old pipeline was refurbished to ship natural gas liquids (a byproduct of fracking) to the eastern seaboard. This original refurbished pipeline transports approximately 70,000 barrels a day of natural gas liquids such as ethane, propane, and butane from Pennsylvania, Ohio, West Virginia, and other states to delivery points within PA, culminating at the Marcus Hook Industrial Complex for exportation to Europe, primarily Scotland and Norway.

On October 2, 2014, the Pennsylvania Public Utility Commission (POC) voted to continue the Sunoco Pipeline’s status as a public utility corporation for the transport of liquid petroleum products within the state [8]. Just prior to the POC’s decision, the Sunoco Pipeline announced plans to add two more pipelines, called Mariner II and Mariner 2X, which will be situated primarily alongside the older Mariner I pipeline and bring the capacity of transport to 345,000 barrels per day and 250,000 bpd, respectively [8]. The pipeline will traverse 17 counties in the southern tier of Pennsylvania. When the Mariner East 2 is completed, Sunoco plans to begin work on its parallel expansion pipeline, called the Mariner East 2X. The company has not announced an expected completion date for the ME2X [1].
Project Area (in hectares)1,300
Level of Investment (in USD)5,100,000,000
Type of PopulationSemi-urban
Potential Affected Population105,500
Start Date11/05/2017
Company Names or State EnterprisesEnergy Transfer Partners (formerly Sunoco Logistics). (ETF) from United States of America
Relevant government actorsPennsylvania Public Utility Commission (PUC)

Pennsylvania Department of Environmental Protection (DEP)

Commonwealth of Pennsylvania
Environmental justice organisations and other supportersDel-Chesco United for Pipeline Safety;

East Goshen Safety and Environmental Advocates (;

Pennsylvania Alliance for Clean Water and Air;


Clean Air Council (CAC);

Mountain Watershed Association (MWA);

Delaware Riverkeeper Network (DRN)
The Conflict and the Mobilization
Intensity of Conflict (at highest level)MEDIUM (street protests, visible mobilization)
When did the mobilization beginIn REACTION to the implementation (during construction or operation)
Groups MobilizingInternational ejos
Local ejos
Local government/political parties
Recreational users
Local scientists/professionals
Forms of MobilizationCommunity-based participative research (popular epidemiology studies, etc..)
Creation of alternative reports/knowledge
Development of a network/collective action
Involvement of national and international NGOs
Land occupation
Lawsuits, court cases, judicial activism
Media based activism/alternative media
Official complaint letters and petitions
Public campaigns
Street protest/marches
Environmental ImpactsVisible: Air pollution, Global warming, Loss of landscape/aesthetic degradation, Noise pollution, Soil contamination, Waste overflow, Oil spills, Deforestation and loss of vegetation cover, Surface water pollution / Decreasing water (physico-chemical, biological) quality, Groundwater pollution or depletion, Other Environmental impacts
Potential: Biodiversity loss (wildlife, agro-diversity), Fires, Food insecurity (crop damage), Large-scale disturbance of hydro and geological systems
OtherConfirmed risk of gas explosions
Health ImpactsVisible: Accidents, Exposure to unknown or uncertain complex risks (radiation, etc…), Other Health impacts
Potential: Mental problems including stress, depression and suicide, Violence related health impacts (homicides, rape, etc..) , Deaths
Socio-economic ImpactsVisible: Displacement, Violations of human rights, Land dispossession, Other socio-economic impacts
Potential: Increase in Corruption/Co-optation of different actors, Increase in violence and crime, Militarization and increased police presence, Specific impacts on women
Project StatusUnder construction
Pathways for conflict outcome / responseCompensation
Court decision (failure for environmental justice)
Project temporarily suspended
Development of AlternativesOne individual proposed a 'safer' pipeline that would require a mile-wide berth along the 300-mile long pipeline, in the case of accidents. Another solution proposed was to convert the liquid gases to something less volatile. Other solutions would be to stop fracking shale gas due to the detrimental impacts of fossil fuel production on the climate and subsidize a transition to renewable energy.
Do you consider this as a success?No
Why? Explain briefly.Sunoco has a consistently bad record of spills and mismanagement of its infrastructure, and the regulatory agencies have permitted them to proceed with a pipeline carrying highly hazardous hydrocarbons despite the appearance of sink holes, significant litigation, and public outcry. The suspension of activities was only temporary, but later the pipeline was permitted to proceed. The regulators have taken a stance similar to the companies - stall and finish the construction. They believe that once the pipeline is in the ground it will be out of sight and mind. The construction of Mariner II is not a success but a failure for environmental justice.
Sources and Materials

Feb 2018: proceedings from Clean Air Council, deMarteleire and Bomstein vs. Sunoco Pipeline L.P.
[click to view]

March 7, 2018 PUC Issues Emergency Order Regarding Sunoco Pipeline L.P.; Operations of Mariner 1 East Pipeline Suspended Over Safety Concerns
[click to view]

May 3 2018: DEP Levies Additional $355,000 Penalty Against Sunoco for Mariner East 2 Violations
[click to view]

AUg 6, 2018 DEP Assesses $148,000 Penalty Against Sunoco for Mariner East 2 Violations in Berks, Chester and Lebanon Counties
[click to view]


[15] 2015. Negotiating Pipeline Rights-of-Way in Pennsylvania
[click to view]


(AUGUST 7, 2018)
[click to view]

[7] Assessment of Undiscovered Oil and Gas Resources of the Ordovician Utica Shale of the Appalachian Basin Province, 2012: United States Geological Survey, Fact Sheet 2012-3116, September 2012.
[click to view]

Industry report about impacts on property values for homes co-existing with pipelines
[click to view]

DEP Fact Sheet: Sunoco Pennsylvania Pipeline Project/ Mariner East II
[click to view]


[2] June 10, 2014 Critics challenge Sunoco Pipeline as public utility
[click to view]

[6] Utica Shale - The Natural Gas Giant Below the Marcellus
[click to view]

[12] June 2017 Pennsylvanians speak out about losing their land to a Sunoco pipeline
[click to view]

[13] 2015. Negotiating Pipeline Rights-of-Way in Pennsylvania
[click to view]

[8] June 2018: Sunoco Pipeline: PUC Confirms Mariner East 1 Operation is Safe; Approves Restart
[click to view]

[9] List of those who have been harmed by fracking from Utica and Marcellus Shale
[click to view]

[3] April 4, 2018: Sunoco, residents at odds over claim of new ‘sinkholes’ near pipeline construction in Edgmont
[click to view]

[11] Your Guide to pipelines
[click to view]

[16] July 23, 2018: A fateful 2014 decision confounds foes of Sunoco's Mariner East pipeline
[click to view]

[4] March 7, 2018 PUC orders Sunoco pipeline shutdown after sinkholes expose bare pipe near Exton
[click to view]

[1] June 1, 2018: How Sunoco’s Mariner East pipeline is affecting real estate prices in Pa.’s Chester and Delaware Counties
[click to view]

[5] July 18, 2018 Desperate for answers, suburban groups bankroll two-county study of Sunoco pipeline
[click to view]

[17] Mariner East 2: At-Risk Schools and Populations
[click to view]

[18] Key Dates in Dragonpipe History
[click to view]

Inventory of news about the pipeline
[click to view]

Letter: What needs to be done to make Mariner East 2 safe
[click to view]

DEP's website on Mariner II Pipeline Project
[click to view]

Coalition fighting pipeline accused of damaging pipeline
[click to view]

The Dragonpipe Blog: Comprehensive blog of all the happenings of the Sunoco Pipeline, Mariner II, The Dragonpipe, the dragon ships, and this blog
[click to view]

Other Documents

Utica Shale Gas deposits Location of the oil and gas assessment units (AU) for the Utica Shale in the Appalachian Basin Province. (USGS 2012)
[click to view]

Meta Information
ContributorJulie L. Snorek, Autonomous University of Barcelona, [email protected]
Last update23/08/2018