Some residents of Delaware and Chester counties say they've been dealing with problems like water contamination since construction started.
"Just down the road from here, Edgemont Township has been the victim of three Sunoco incidents," said Eric Friedman.
"In June of 2018, one of their pipelines failed, ruptured into Darby Creek."
But people who live near the pipeline say water contamination is just one of their issues with Mariner East.
"We first found out about Mariner East in the spring of 2015, when a land agent came to tell us that they had a easement that they wanted us to sign," said Ginny Kerslake, who lives in Chester County near the pipeline. "And at the time they told us that they were going to be putting through some pipelines that would be just like all the other ones that we've been living with. That they had eminent domain. And that we would have no choice to sign it. Even if we didn't sign it, they would do the work anyway, and they would take us to court."
This week on KYW In Depth, Charlotte Reese went to Thornbury Township, Delaware County, to talk to people who say their lives have changed ever since work on the pipeline started in their backyards. This episode is the story of what they have to say about the pipeline, and how its owner, Energy Transfer, is upholding the multibillion-dollar project as the safest way to transport natural gas liquids that will bring economic growth to the region.