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Press Release

Sunoco Provides Notice of Intent to Restart Mariner East 1 Pipeline; Additional Safety Steps to be Taken Related to Mariner Pipelines

Published on 4/19/2019

Filed under: Gas

HARRISBURG – The Bureau of Investigation and Enforcement (I&E) – the independent investigation and enforcement bureau of the Pennsylvania Public Utility Commission (PUC) – today received notice from Sunoco Pipeline LP, a/k/a Energy Transfer Partners (SPLP or Sunoco), of Sunoco’s intent to restart the Mariner East 1 (ME1) pipeline. Sunoco will also take a series of additional steps to address safety concerns regarding the Mariner East Pipelines.

Mariner East 1 (ME1) has been out of service since Jan. 20, 2019, as engineers from I&E’s Pipeline Safety Division monitored stabilization and remediation efforts undertaken by SPLP following a subsidence event or “sinkhole” that exposed a small segment of the pipeline along Lisa Drive in West Whiteland Township, Chester County. 

The January agreement between I&E and Sunoco related to the voluntary shutdown of ME1 required 72-hour notice of intent to restart that pipeline. Notice was provided to I&E at approximately 3 p.m. today.

Engineers from I&E’s Pipeline Safety Division will be on site at Sunoco’s offices on Monday, April 22, to monitor startup procedures.

Enhanced Safety Actions

Enhanced safety actions to be undertaken by Sunoco include:

  • I&E and Sunoco have agreed upon a plan to further remediate the Lisa Drive area surrounding ME1. The site remediation plan will contain a going-forward approach based on all data collected to date. The site remediation plan will also consider the impact of the planned or anticipated open trench excavation of the 20-inch Mariner East 2 line, and the plan will be submitted to I&E for review by I&E’s consultants. 
  • SPLP will commit personnel to walk the Lisa Drive section of ME1 daily, except where inclement weather would put personnel in danger, until the grouting along ME1 is complete. SPLP will further provide I&E with summary reports describing the observations recorded during each visual inspection.
  • Sunoco will perform geophysical tests in the right-of-way area behind Lisa Drive every six months for two years, and report the findings to I&E.
  • SPLP will maintain the existing top-of-pipe elevation survey locations and strain gauges on this section of ME1 and will continuously monitor strain gauge data in its control room that is staffed 24/7, and routinely provide reports to I&E.  

I&E also noted the following regarding the ongoing safety monitoring of the Mariner East pipelines:

  • SPLP installed strain gauges on ME1 in the Lisa Drive area in 2018.  The strain gauge data to date has not revealed any movement of ME1 before, during or after the subsidence event. SPLP conducts remote monitoring of the strain gauges from its control room which includes the ability to react to any aberrations to strain readings including shutting down the line section at issue.
  • SPLP’s work to stabilize the ground in the vicinity of this latest subsidence near Lisa Drive has been constantly monitored by I&E’s Pipeline Safety personnel and geophysical consultants. I&E’s geophysical and engineering experts have met and conferred with SPLP and its geophysical experts on numerous occasions during the past three months. 

About the Bureau of Investigation & Enforcement

As the independent investigation and enforcement bureau of the PUC, I&E enforces state and federal pipeline safety and motor carrier safety laws and regulations and represents the public interest in ratemaking and service matters before the PUC’s Office of Administrative Law Judge.  I&E has the authority to bring enforcement action, seek emergency orders from the Commission or take other steps to ensure public safety.

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