The Pennsylvania Department of Environmental Protection (DEP) has approved Sunoco Pipeline LP’s requests to modify permits at three horizontal directional drill (HDD) sites for its Mariner East natural gas pipeline system.

Mariner East

The DEP announced the approval earlier this week, which alters the pipeline developer’s erosion and sediment control, as well as the “water obstructions and encroachments” permitting.

The modifications primarily relate to pipeline installation methods at the HDD 620 site in Middletown Township, Delaware County; the HDD 280 site in Upper Uwchlan Township, Chester County; and the HDD 400 site in West Whiteland Township, also in Chester County.

“These approvals have undergone substantial and thorough reviews by technical staff, with careful...