This story originally appeared on StateImpact Pennsylvania.
A new sinkhole appeared late Sunday at a Sunoco pipeline site in Chester County where several earlier sinkholes led officials to halt construction because of concerns for public safety.
Sunoco confirmed the existence of the hole at Lisa Drive, a suburban development in West Whiteland Township where critics argue the geology is too unstable to support new and existing pipelines that are part of the controversial Mariner East project.
The new hole exposed Mariner East 1, a 1930s-era pipeline that has been repurposed to carry natural gas liquids along the same route where two new Sunoco pipelines are being built.
As a community group and a Chester County state senator called for the pipeline project to be shut down because of public safety concerns, Sunoco said Monday it is working with state officials to ensure the stability of the ground at Lisa Drive.
“We are working in coordination with the PUC’s Bureau of Investigation and Enforcement and its consultants to perform activities beginning today to ensure the area remains stable,” said Vicki Granado, a spokeswoman for Sunoco’s parent, Energy Transfer.
On Sunday, Sunoco said in a statement that there was “no impact” to the exposed Mariner East 1, “but we have voluntarily shut it out of an abundance of caution.” It said it would work with the Public Utility Commission, local officials and first responders.
Chester County Department of Emergency Services said the hole was about five feet wide and 10 feet deep, and had left the pipeline “exposed but undamaged.”
It said in a statement on Sunday that there was no impact to public safety and the incident had been closed, but Sunoco and the PUC would continue to investigate.
Nils Hagen-Frederiksen, a spokesman for the Pennsylvania Public Utility Commission, said Sunday that a safety engineer and other officials were en route to “the site of an incident” on Lisa Drive. The PUC is jointly responsible for pipeline safety, along with the federal Pipeline and Hazardous Materials Safety Administration, and has authority from PHMSA to enforce the federal regulations.
On Monday morning, with the temperature around 10 degrees, workers drove a backhoe into the site where the sink hole was surrounded by orange plastic fencing.
John Mattia, whose house is about 60 feet from the new sinkhole, said it undermines any confidence he may have had in Sunoco’s ability to build and operate the pipelines safely.
“I find it alarming to say the least that in an area that they say they already remediated there is a new sinkhole,” said Mattia, 48, who has lived in the house for 17 years. “To have this happen again and to expose the pipeline completely, I find despicable.”
Lisa Drive became a cause celebre for Mariner East opponents in early 2018 when sinkholes opened up in the backyards of five houses where Sunoco is building the new pipelines on an existing right of way.
The earlier sinkholes also exposed a section of Mariner East 1, prompting a PUC judge to shut down the pipe and halt construction of the two new lines on the grounds that there was an “imminent risk” to the public.
After the earlier sinkholes were filled, the full PUC later allowed ME1 operation to resume, but upheld the ban on new pipeline construction at that location until lifting it in August.
State Sen. Andy Dinniman, (D-Chester), a persistent critic of the Mariner East project, said the new sinkhole undermines confidence in the PUC after it allowed the project to resume at Lisa Drive last summer, overturning a judge’s ruling in response to a petition filed by Dinniman.
“Clearly, the PUC process is broken when it comes to pipeline safety,” Dinniman said in a statement. “The fact that they overturned their own judge’s decision and allowed its operation to continue has eroded any lingering hope or faith that they will protect the public.”
He said the entire Mariner East project should be shut down pending an independent review of Sunoco and the PUC’s oversight of it.
Responding to Dinniman, the PUC’s Hagen-Frederiksen said officials have been investigating the new sinkhole on-site since Sunday, and said there are “numerous” other complaints against Mariner East before the PUC. “The Commission’s actions in each of those cases will be guided by the facts, the evidence and the law,” he said.
Asked whether the PUC would have to approve a restart for Mariner East 1, Hagen-Frederiksen said the PUC’s current focus is on the safety investigation, and that discussions about conditions for a restart will come “in the future.”
Del-Chesco United for Pipeline Safety, a community group, said the new sinkholes are the latest evidence that the pipeline project is a threat to public safety.
“This needs to be shut down immediately for the safety of the public,” the group said in a Facebook post. “This area has not been stabilized for over 15 months.”
Critics say the Mariner East pipelines pose a grave risk to public safety because of the highly volatile nature of the material they are carrying. Last week, the PUC upheld a judge’s denial of an emergency request by seven residents of Chester and Delaware Counties to halt both the operation of Mariner East 1 and the construction of Mariner East 2 and 2X until public safety can be assured.
The plaintiffs had asked for the emergency shutdown while the judge reviews their request to permanently shut down the lines.
Mariner East 2 was planned as a 20-inch pipeline. But because the full length of the 20-inch line will not be finished until 2020, the company said, it would join three different pipelines to create a hybrid through which natural gas liquids will flow temporarily. The company says it is calling that hybrid line Mariner East 2. It went into service in late December, Sunoco said.