Sunoco Pipeline LP is challenging a recent directive from state regulators to suspend work on a horizontal directional drill (HDD) in Chester County, PA, needed to complete parts of its embattled Mariner East pipeline system.

Mariner East

A prolonged construction stoppage at the site in West Whiteland Township, dubbed HDD 360, creates “a significant risk of adverse consequences at this work location” including “a complete loss of the HDD over 2,800-foot borehole, and the continued discharge of groundwater through the existing pilot hole,” Sunoco’s legal representation wrote in an appeal filed Sunday with the Pennsylvania Environmental Hearing Board.

The appeal seeks to overturn a Notice of Violation (NOV) issued last Thursday by the Pennsylvania Department of Environmental Protection (DEP); the NOV came in response to reports of “a discharge of turbid groundwater” near the Chester County HDD site on Aug. 8 and advised that the company would need DEP approval to restart drilling operations.

For its part, Sunoco argued that the latest action contradicts a contingency plan for the HDD 360 location approved earlier this year by DEP. The operator urged the board to allow work to resume and “to allow HDD 360 to complete construction in accordance with the plans and protocols previously approved” by DEP.

Suspending work on the project “has caused, and will continue to cause, irreparable injury” to both Sunoco and the public, “most notably the local community and residents who will now face yet another extension of the completion of construction activity near their homes,” according to the company’s filing.

In addition to the discharge in West Whiteland Township, the DEP also responded to a reported discharge earlier this month at the Marsh Creek State Park in Upper Uwchlan Township.

The incidents at Upper Uwchlan and West Whiteland are the latest in a long line of problems that the project has encountered.  

While inadvertent returns are a common occurrence during HDD work, Sunoco has had repeated issues throughout Pennsylvania during construction of Mariner East. Drilling fluid spills, impacts to local water supplies and other violations during construction of the system have resulted in more than $13 million in fines.

Mariner East, which consists of three pipelines in various stages of development and service, has faced constant regulatory and legal challenges that have led to delays and operational problems. It moves natural gas liquids from processing facilities in Ohio, Pennsylvania and West Virginia to the Marcus Hook Industrial Complex near Philadelphia.