Crews work to stabilize sinkholes in a West Whiteland Township neighborhood on March 3. The sinkholes appeared near a construction site for the Mariner East 2 pipeline.

Eric Friedman

Sunoco says PUC asked for expanded work to ‘stabilize’ ground at Chester County pipeline site

  • Jon Hurdle
Crews work to stabilize sinkholes in a West Whiteland Township neighborhood on March 3. The sinkholes appeared recently near a construction site for the Mariner East 2 pipeline.

Crews work to stabilize sinkholes in a West Whiteland Township neighborhood on March 3. The sinkholes appeared recently near a construction site for the Mariner East 2 pipeline. The PUC ordered Sunoco to shut down nearby Mariner East 1 until it can prove the line is safe to operate amid the sinkholes and geology of the region.

Sunoco is preparing to drill 10 more holes behind homes in Chester County’s West Whiteland Township to stabilize land where sinkholes raised concerns about the safety of an existing pipeline and two more under construction there.

The company said the project is being undertaken at the request of the Public Utility Commission to stabilize the ground, and not because of any continuing concern about the safety of the existing line, Mariner East 1.

Lisa Dillinger, a spokeswoman for Sunoco’s parent, Energy Transfer Partners, repeated an earlier statement that the company has completed an investigation of ME1, as ordered by the PUC, and found no safety issues with that line, or with the new Mariner East 2 line, which is being built on the same right-of-way.

“The PUC asked us to expand our grouting program as a precaution to further stabilize the area to the east of our ME 1 line,” Dillinger said in a statement. “In order to do this grouting, you must drill bores. As we already had the equipment onsite from our earlier work, we agreed. This grouting is not based on the integrity testing results for ME1, nor ME2 construction.”

Grouting involves filling a drilled hole with a cement mixture whose composition depends on the data from the bore hole, Dillinger said.

The investigation of ME1 began in early March when the PUC halted its operation in an emergency order because of what it said was a potential “catastrophe” if the line was breached by unstable geology or the adjacent new construction. Several sinkholes, which began to appear in late 2017, have now been filled. The company has been investigating the integrity of the pipeline, which dates from the 1930s, to comply with the PUC’s order.

The new work was notified by a local attorney for Sunoco/Energy Transfer Partners to Andrew Neuwirth, a lawyer for two of the residents of Lisa Drive, where the work will take place.

“Sunoco Pipeline LP’s contractors will be installing 10 new bore holes to further investigate ME1 which will be grouted after they are complete,” said the notification from Sunoco’s local lawyers, Manko, Gold, Katcher & Fox, based in Bala Cynwyd outside Philadelphia. It said the work is likely to begin Wednesday or Thursday.

Nils Hagen-Frederiksen, a spokesman for the PUC and its Bureau of Investigation and Enforcement, would not say whether the PUC ordered the new holes to be drilled or whether it indicates that geological problems at the site are more serious than first thought.

Asked whether the PUC has determined ME1 is safe, he said only that the emergency order, which halted operations until its safety was demonstrated, remains in place.

“The BI&E investigation is active and ongoing, and our pipeline safety engineers continue to meet and communicate with Sunoco on a daily basis,” Hagen-Frederiksen said. “Future actions by the Commission will be contingent upon whether and how the terms and conditions of the Emergency Order are satisfied.”

In the order, the PUC first said the investigation of ME1 would take about 10-14 days. That period was extended by Sunoco in late March when it offered to relocate residents of the five houses on Lisa Drive for an estimated four to six weeks for what it called an additional investigation.

It was not immediately clear whether the new plan to drill 10 more holes would further extend the investigation period.

“My clients on Lisa Drive have had their lives turned upside down by Sunoco’s work on the Mariner East 1 pipeline,” said Neuwirth, who represents homeowners Russell and Mary March. “This latest development suggests to me that Sunoco is still searching for answers as to what went wrong with the pipeline.”

He said the Marches have decided to stay in their home rather than move out at Sunoco’s expense while the work is going on, in part because it’s not easy to find a temporary home for their dog.

Neuwirth, who is suing Sunoco on behalf of the Marches and several other residents, said the new drilling indicates that the company didn’t fully investigate the geology at the site before drilling for the Mariner East 2 and 2X lines.

“Why didn’t they do the investigation ahead of time?” Neuwirth asked. “Every step of the investigation they do now is evidence of what they could have done and should have done before running this through a highly populated area.”

Neuwirth predicted that more information about the Lisa Drive work will come out at a public hearing being held by the Department of Environmental Protection in West Chester on April 30 to discuss Sunoco’s plans to change its drilling technique at two other West Whiteland sites.

Critics of the Mariner East project, including State Sen. Andrew Dinniman, D-Chester County, say that Sunoco should not have been drilling through karst, a type of limestone geology, which he says is too unstable to support horizontal directional drilling.

Mariner East 2, costing more than $2.5 billion, is scheduled to start operating by the end of June. When complete, it will carry ethane, propane and butane across the state from southwest Pennsylvania to a terminal at Marcus Hook near Philadelphia where most of it will be exported.