Risk assessment quantifies Mariner East hazards for residents in two counties

Campaigners raised $46,000 for independent evaluation after Wolf, PUC denied requests

Jon Hurdle

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Jon is an experienced journalist who has covered a wide range of general and business-news stories for national and local media in the U.S. and his native U.K. As a former Reuters reporter, he spent several years covering the early stages of Pennsylvania’s natural gas fracking boom and was one of the first national reporters to write about the effects of gas development on rural communities. Jon trained as a general news reporter with a British newspaper chain and later worked for several business-news organizations including Bloomberg News and Market News International, covering topics including economics, bonds, currencies and monetary policy. Since 2011, he has been a freelance writer, contributing Philadelphia-area news to The New York Times; covering economics for Market News, and writing stories on the environment and other subjects for a number of local outlets including StateImpact. He has written two travel guidebooks to the European Alps; lived in Australia, Switzerland, Israel, and Saudi Arabia, and visited many countries including Ethiopia, Peru, Taiwan, and New Zealand. Outside of work hours, Jon can be found running, birding, cooking, and, when weather permits, gardening in the back yard of a Philadelphia row home where he lives with his partner, Kate.

Marie Cusick / StateImpact Pennsylvania

Construction on the Mariner East 2 pipeline has faced myriad problems, including damaged water supplies and sinkholes in a residential neighborhood in Chester County.

August 29, 2018 | 9:42 AM

Pipeline-safety campaigners unveiled an independent study of whether the Mariner East pipelines will threaten public safety, and the report calculates that an individual has a one in 81,000 chance of dying if he or she is directly above a leak or explosion by all three of the Sunoco pipelines.

Such a person is much less likely to die from a Mariner East leak than he or she is from heart disease but much more likely to do so than from a lightning strike, according to the study, whose results were announced to about 250 people at a West Chester middle school auditorium late Tuesday.

The study by Quest Consultants, an Oklahoma company that assesses industrial risk for government and private clients, found that the biggest risk was faced by people who live near valve stations; entry and exit points for horizontal directional drilling along the pipeline; and places where Mariner East 1, 2 and 2X run along the same right of way.

But it said the risk of an individual dying is “essentially zero” more than half a mile away from Mariner East 2 and 2X, and a quarter of a mile away from Mariner East 1, a 1930s-era pipeline that has been repurposed to carry natural gas liquids. And even though there is a heightened risk where the pipelines are co-located, it is still only 10 percent of the risk of dying in a car accident, the study said.

Quest assessed individual risk at three locations: the Delaware-Chester County line, the Chester County Library, and Middletown’s Glenwood Elementary School, which is about 600 feet from the pipeline route and has been used by pipeline opponents as an emblem of vulnerability.

Using federal government data, the consultant calculated that a pipeline “release” such as a small leak or a major rupture was likely to occur once every 79 years along a 35-mile stretch of pipeline such as that through the two counties.

Throughout Pennsylvania, which will contain about 1,000 miles of Mariner East pipeline when all three lines are completed, a release is likely to occur about every 2.8 years, the study said.

It calculated the consequences of different kinds of leaks. They ranged from burns for anyone with 60 feet of a quarter-inch leak of propane from ME2, resulting in a “jet fire,” to a 2,130-foot “flammable cloud” resulting from a 20-inch rupture of the propane-carrying pipe.

The “Citizens Risk Assessment” was commissioned by Del-Chesco United for Pipeline Safety, a coalition of 14 community groups in Delaware and Chester counties near the eastern end of the 350-mile cross-state pipeline route.

Campaigners raised $46,000 to pay for the study after failing to persuade Gov. Tom Wolf and the Public Utility Commission to do its own study on the probability of a pipeline leak or rupture and its consequences.

Jeff Marx, a senior engineer for Quest who presented its findings, said the study was the company’s first to be paid for with “crowd-funding.”

Pipeline opponents have long argued that the Mariner East project represents a grave risk to public safety because it will carry highly explosive natural gas liquids through Philadelphia’s densely populated western suburbs where residents would have little or no notice of a pipeline emergency, and few options for ensuring their safety if it happened. They commissioned the new study in the hope of providing an objective body of data, not emotion, on the project’s risks.

George Alexander, a member of Del-Chesco, called the Mariner East project an “experiment” by Sunoco, since it is the only one of 14 highly volatile liquids pipelines nationwide to run through such a densely populated area.

In closing remarks to the two-hour meeting, he said the risk assessment was purely based on the exposure of one individual, and did not consider the population as a whole. “If there are others standing there, this study doesn’t take that into account,” he said.

Alexander said he hopes the report will be used by emergency services to plan for any leak in the line; by planners who can take it into account when deciding whether to allow certain buildings; and by people who will now be better informed about the potential consequences of living with a natural gas liquids pipeline.

Little more than a month before Sunoco says it will start operating ME2, Alexander said he still aims to stop the pipeline, arguing that the company has often missed its previous targets to start operations.

“We have always been within a few months of when Sunoco said its pipelines would be finished,” he said after the meeting. “They are not finished.”

The Pennsylvania Energy Infrastructure Alliance, which advocates for Mariner East, dismissed the risk assessment as just another effort to stop the pipeline.

“This project has nothing to do with assessing risk and everything to do with efforts aimed at shutting down the Mariner East pipeline projects,” said PEIA spokesman Kurt Knaus, in a statement.

He accused Quest of bias, citing an earlier study that it did for a pipeline safety group at Middletown, Delaware County. He said the new study is flawed because it uses publicly available information, and lacks other data that is not released for security reasons.

State Sen. Andy Dinniman (D-Chester), a persistent critic of Mariner East and an instigator of the risk-assessment project, said it represents a grassroots effort to evaluate the issue in the face of government inaction.

“When the government won’t do what it’s supposed to do, when the PUC won’t do what it’s supposed to do, the people themselves have organized,” Dinniman said.