Pennsylvania PUC issues emergency order to suspend operation of Mariner East 1 pipeline

The Pennsylvania Public Utility Commission (PUC) issued Wednesday an Emergency Order directing Sunoco Pipeline L.P., also known as Energy Transfer Partners (Sunoco), to suspend operations of the Mariner East 1 Pipeline (ME1).

The order also requires Sunoco to conduct additional testing and analysis on the line.

THe PUC issued the emergency order in response to a Petition for an Ex Parte Emergency Order filed by the PUC’s independent Bureau of Investigation and Enforcement (BIE). Engineers from the PUC’s Pipeline Safety Division investigated reports of the formation of sinkholes near the ME1 in Chester County.

ME1 is an eight-inch diameter Natural Gas Liquids (NGL) pipeline, which transports liquid propane, butane, and ethane. A total of three sinkholes have been discovered near or in the path of ME1.

The sinkholes have also appeared near the area where construction, including Horizontal Directional Drilling (HDD), is ongoing for a new pipeline called Mariner East 2.

The order requires Sunoco to conduct testing of the pipeline within 24 hours of the entry of the order. Within 12 hours of completing the required testing, Sunoco must suspend hazardous liquids transportation service on the pipeline for a period of time, which BIE and Sunoco estimate will be 10 to 14 days.

Before Sunoco can reinstate this service, it must complete the required inspections and test, take any necessary corrective action to the satisfaction of BIE and receive approval from the PUC.