Mariner East 1 Pipeline Resumes Service


The Mariner East 1 pipeline returned to service after a three-month shutdown, according to reports. The shutdown occurred after a sinkhole was found in Chester County, Pennsylvania, which exposed a section of the pipeline.

In January of last year, Pennsylvania officials stopped construction of Sunoco Pipeline’s Mariner East 2 pipeline after a series of incidents in which drilling fluids were released into the environment over the course of seven months.

Mariner Pipeline Projects

In January 2018, the Pennsylvania Department of Environmental Protection issued the order suspending construction on the Mariner East 2 after issuing 32 notices of violation to Sunoco between May 9 and Dec. 22, 2017. Violations were largely related to “inadvertent returns” of fluids from horizontal directional drilling, considered to be industrial waste.

Mariner East 2 is set to move ethane, propane and other petroleum products from Ohio and West Virginia east to the Philadelphia region. The DEP’s order, however, halted all construction (other than basic site maintenance activities).

Mariner East 2 is being constructed of 350 miles of 16-inch pipe and 250 miles of 20-inch pipe, most rolled, milled and coated in the United States, according to Sunoco. The first Mariner East pipeline, 300 miles long, was completed in 2016 and conveys liquid propane and ethane from the Marcellus shale drilling region of Western Pennsylvania east to Sunoco’s Marcus Hook, Pennsylvania, refinery.

Sunoco Pipeline is a subsidiary of Energy Transfer Partners, the company behind the Dakota Access Pipeline, which runs from North Dakota to Illinois.

In May 2018, Pennsylvania Public Utility Commission Judge Elizabeth Barnes ordered the suspension of gas transportation through Sunoco’s Mariner East 1 pipeline, while also stopping any further construction on the Mariner East 2 pipelines, citing contaminated water wells, sinkholes and poor managerial decisions on the company’s part.

And, late last month, Pennsylvania Attorney General Josh Shapiro and the Delaware County district attorney’s office announced that both would be launching an investigation into Mariner East 2.

Resuming Service

Sunoco Pipeline announced Friday (April 19) plans for the Mariner East 1 pipeline to resume service. PUC spokesperson Nils Hagen-Frederiksen noted that engineers would be on site on Tuesday morning to monitor restarting activities.

Additional safety measures are part of the deal Sunoco struck with the PUC, which are targeted toward the West Whiteland Township site, including site remediation and additional daily inspections during grouting, as well as conducting geophysical testing every six months for the next two years.

Strain gages, which have been installed on site since 2018, did not indicate that the pipeline had moved at all before or after the sinkhole was found, the PUC noted.

Sunoco expects to complete the Mariner pipelines, including 2X, by the end of 2020. Collectively, the three pipelines are slated to carry 675,000 barrels a day of ethane, propane and butane.


Tagged categories: Government; Infrastructure; NA; North America; Oil and Gas; Pipelines; Program/Project Management

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