Delaware County emergency chief says he couldn’t evacuate everyone if a major Mariner East pipeline leak occurred

A Mariner East pipeline valve site on the edge of the Andover development, Thornbury Township, Delaware County, illustrates the pipeline's path through densely-populated southeastern Pennsylvania. (Jon Hurdle/StateImpact Pennsylvania)

A Mariner East pipeline valve site on the edge of the Andover development, Thornbury Township, Delaware County, illustrates the pipeline's path through densely-populated southeastern Pennsylvania. (Jon Hurdle/StateImpact Pennsylvania)

This article originally appeared on StateImpact Pennsylvania.

Delaware County’s emergency operations director said Tuesday that authorities would not be able to quickly evacuate everyone within half a mile of a major leak from any of the Mariner East pipelines, but acknowledged that their builder, Sunoco, has attempted to educate the public about how to detect any leak and how to react to it.

Timothy Boyce was giving evidence at the final hearings of a case brought to the Public Utility Commission by seven residents of Delaware and Chester counties who want the PUC to rule on whether Sunoco’s plans to protect the public from any rupture in the pipelines are adequate. The so-called Safety Seven are urging the regulator, if it finds that Sunoco’s plans are lacking, to shut down the lines until safety is improved.

Critics say the safety of people who live near the 350-mile cross-state route is at risk because of the highly explosive nature of the natural gas liquids carried by the pipelines, especially in Philadelphia’s densely populated western suburbs.

A crowd-funded report on the consequences of a major leak in Delaware and Chester counties predicted in 2018 that anyone within 60 feet of a quarter-inch leak of propane – one of the natural gas liquids – would be burned by what it called a “jet fire.” A 20-inch rupture of the pipe would release a 2,130-foot “flammable cloud,” according to the report by Quest, a consultant hired by Del-Chesco United for Pipeline Safety, a community group.

Still, the report said residents are much less likely to die from a Mariner East leak than they are from heart disease or a car accident.

Boyce, appearing before Administrative Law Judge Elizabeth Barnes as a witness for the complainants, said any “catastrophic” leak would likely result in injuries and property damage.

“If you want to ask can you evacuate a half-mile in one of the most densely populated areas in 10 minutes, the answer is no,” he said, in answer to a question by Laura Obenski, an independent complainant. “If it’s a catastrophic release, for us to say there’s going to be no injuries and no property damage, no, that’s unlikely.

“The evacuation issue, which to me would be one of the hardest things we would face if this product was released catastrophically – you are talking about a large area that needs to be addressed, a lot of people need to be communicated with, and very dense populations. We do not have that capacity,” he said.

But under questioning from Robert Fox, an attorney for Sunoco, Boyce said the company has taken steps to warn the public about the potentially hazardous nature of the products being carried by the lines, and had distributed brochures describing what to do in the case of a leak.

Sunoco’s instructions include how to recognize a leak, Boyce said, but he acknowledged that there’s no requirement to add odor or color to the NGLs so that they can be detected by the public. And he said he was unaware of any regulation demanding that a pipeline builder install an early-warning system for any leak.

“When a product is odorless – and that’s true of the product we are dealing with here – that’s difficult,” he said. “Anything that’s not easy to detect is going to be harder to develop a plan to respond.”

Opponents of the pipelines have derided Sunoco’s emergency instructions, asking how residents could recognize a leak of the colorless and odorless liquids, which are pumped through the line in gaseous form. They also question how anyone suspecting a leak can notify authorities when they are also advised not to use potential ignition sources like cellphones or cars.

George Alexander, a spokesman for Del-Chesco United, said the hearings would likely be a “critical milestone in the Mariner East saga.” Although construction is not yet complete, NGLs have been flowing since December 2018 when Sunoco joined together sections of different-diameter pipes so that the fuel could start moving from southwestern Pennsylvania and Ohio to an export terminal at Marcus Hook near Philadelphia.

Boyce said a catastrophic leak in the line would likely overwhelm the ability of authorities to quickly ensure public safety.

“If there’s a rupture in the pipeline and it ignites relatively quick, you are going to have damage in the area, you are going to have potential injuries in the area,” he said. “I am concerned every day about our ability to serve the whole community.”

The PUC, as the state’s pipeline regulator, has been under pressure since the start of Mariner East construction in February 2017 to crack down on what critics say are sloppy construction practices by Sunoco. Dozens of drilling mud spills have damaged private water wells, leading to several state-ordered shutdowns and about 100 notices of violation by the Department of Environmental Protection.

Opponents include several school districts along the line. A representative of one of the districts is due to testify on Wednesday, along with a township official and other witnesses.

The hearing is due to continue until Oct. 14. After that, the parties are required to submit written briefs and responses by the end of the year. Judge Barnes will then submit her recommendations to the full commission which will make a final decision to accept or reject them.

Here’s the docket for the upcoming hearing sessions.

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