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Press Release

PUC Update on Investigation Involving Mariner East 1 Pipeline

Published on 1/24/2019

Filed under: Gas

HARRISBURG – The Pennsylvania Public Utility Commission’s (PUC’s) independent Bureau of Investigation and Enforcement (I&E) – which includes the PUC’s Pipeline Safety Division – continues its active and ongoing safety investigation regarding the Mariner East 1 (ME1) pipeline, operated by Sunoco Pipeline LP, a/k/a Energy Transfer Partners (SPLP). 

Following discussions with the PUC’s I&E, the remainder of ME1 has been “shut down” by SPLP (since Jan. 21), meaning no product is flowing in this pipeline anywhere in Pennsylvania.  SPLP is not permitted to resume the transportation of product through ME1 until approval is received from I&E. 

Additionally, I&E pipeline safety engineers continue to monitor all work at the Lisa Drive site and remain in constant contact with SPLP regarding their activities involving ME1. I&E’s pipeline safety engineers are trained and certificated by the Federal Pipeline and Hazardous Materials Safety Administration (PHMSA). The PUC also continues to use the ARM Group Inc., a leading consulting firm specializing in geotechnical engineering and geophysics, to monitor geological testing of the Lisa Drive site and analyze the results for PUC investigators.

 I&E has also confirmed that the following additional safety measures have occurred:

  • Temporary stabilization work around a “sinkhole” that developed this past weekend (Jan. 20) along Lisa Drive, in West Whiteland Township, Chester County – using flowable fill material and sand to secure an exposed section of the ME1 pipeline – was completed by SPLP on Wednesday, Jan. 23;
  • In order to fully isolate the Lisa Drive location for testing, SPLP is purging a 44-mile section of the pipeline, from Beckersville, Berks County, to Marcus Hook, Delaware County; work to purge the final 3.8-mile segment of that line, from Twin Oaks, in Delaware County, to Marcus Hook, is expected to be completed this evening.
  • Per agreement between I&E and SPLP, this section of line will remain purged during the duration of the I&E investigation into this incident; and,
  • Discussions are underway regarding the geophysical testing that SPLP is required to conduct in the area around the Lisa Drive incident.

All testing will be shared with I&E’s pipeline safety engineers and I&E’s geophysical consultants for independent analysis and review.  Following analysis of these testing results, I&E will determine whether a plan for remediation of the Lisa Drive site, along with any other work that I&E believes is necessary, can be developed.

As the independent investigation and enforcement bureau of the PUC, I&E has the authority to bring enforcement action, seek emergency orders from the Commission or take other steps to ensure public safety, should circumstances change or based on the finding of the investigation.

The Pennsylvania Public Utility Commission balances the needs of consumers and utilities; ensures safe and reliable utility service at reasonable rates; protects the public interest; educates consumers to make independent and informed utility choices; furthers economic development; and fosters new technologies and competitive markets in an environmentally sound manner.

For recent news releases and video of select Commission proceedings or more information about the PUC, visit our website at Follow the PUC on Twitter – @PA_PUC for all things utility. “Like” PA Public Utility Commission” on Facebook for easy access to information on electric shopping.

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