STATE IMPACT PENNSYLVANIA – Safety inspectors at the Pennsylvania Public Utility Commission are recommending that Sunoco’s Mariner East 1 pipeline be restarted after a nearly two-month shutdown prompted by sinkholes that appeared at a pipeline-construction site in Chester County’s West Whiteland Township.
The Bureau of Investigation and Enforcement said it was satisfied that the integrity of the pipeline had not been compromised by the sinkholes that led the PUC to issue an emergency order on March 7 closing down ME1 until the safety of the line could be confirmed.
PUC Chair Gladys Brown said at the time that there could be “catastrophic” consequences if ME1, which carries natural gas liquids, was breached because of its proximity to the sinkholes and to construction of the Mariner East 2 and 2X pipelines at the same site, Lisa Drive.
In early March, the Bureau asked the commission to suspend ME1 operations until it was satisfied that the line’s integrity had not been impaired by the sinkholes, which it said were as much as 20 feet wide and 15 feet deep.
Now, the Bureau says it is satisfied that there’s no threat to the integrity of ME1, which was built in the 1930s and previously carried gasoline to western Pennsylvania. Since the natural gas boom in the Marcellus shale starting in the mid-2000s, the line has been repurposed to carry propane, butane and ethane from western Pennsylvania eastwards to a terminal at Marcus Hook in Delaware County.
“Having considered the corrective action taken by SPLP [Sunoco Pipeline], as well as the corrective action planned to be taken, I&E avers that those concerns have been adequately addressed,” the Bureau said in a document posted on the PUC’s website.
The Bureau said it is “of the opinion that the integrity of the ME1 pipeline has not been compromised by the soil subsidence events that triggered this investigation, and consequently I&E does not oppose SPLP’s request to resume transportation service on its ME1 pipeline.”
The Bureau’s recommendation is due for consideration at a PUC public meeting on Thursday.
The PUC first estimated the investigation would take 10 to 14 days. Sunoco later said it needed to do an additional investigation that would take four to six weeks, and offered to pay for the temporary relocation of residents of the five homes on one side of Lisa Drive because of the disruption caused by excavation in their back yards.
Sunoco said in an April 27 filing with the PUC that it had done “comprehensive” integrity and geophysical tests and had investigated the geology of the area behind the Lisa Drive homes.
“The testing showed that there was no, and is no, impairment to ME1 from the subsidence; that there are no integrity issues preventing the pipeline from restarting, and that geological conditions at the site are suitable for the continued operation of the line,” the company said.
To provide extra protection to the “subsurface,” Sunoco said it would use open-cut construction – in which a pipeline is laid in a trench – rather than the previously planned horizontal directional drilling (HDD) for the remainder of Mariner East 2 construction at the Lisa Drive right-of-way.
“SPLP appreciates that safety concerns trump economic concerns,” the company said in its filing. “However, here the safety allegations have been resolved and the continuing economic impact of this shut-down should be neither disregarded nor compounded by delay.”
Andrew Neuwirth, an attorney for Lisa Drive homeowners Russell and Mary March, who have sued Sunoco, rejected the company’s assurances that ME1 is safe and the geology is stable.
“I believe that the damage to the subsurface and the community has already been done and likely cannot be repaired,” Neuwirth said in a statement. “I believe that Sunoco has already caused damage to home values in the area. Nobody trusts Sunoco’s pronouncements and people are begging for the regulators to protect them from harm.”
ARM, a contractor hired by the Bureau to investigate ME1, said the ground at Lisa Drive had been stabilized by Sunoco’s use of grout.