Sunoco Pipeline agrees to more oversight for Mariner East 2 pipeline

The two sides reached a draft settlement agreement that may avert a hearing before Pennsylvania’s Environmental Hearing Board if the judge in charge of the case approves the details.

A ban on many of Sunoco’s horizontal directional drilling (HDD) sites, imposed by Judge Bernard Labuskes on 25 July, remains in place until he decides whether to sign off on the deal.

The hearing that was due to begin today has been cancelled.

If the judge confirms the agreement, Sunoco will take steps to protect private water wells, some of which were contaminated by the drilling in recent months. The company agreed to notify landowners within 450 ft of a horizontal drilling location ten days before it starts work there, and to offer to test their water before, during and after the operation.

“Sunoco will immediately notify a landowner with a water supply within 450 ft of an HDD when Sunoco or the Department has determined that there is a substantial possibility that the operation of the HDD will impact his or her water supply,” the agreement said.

The company also agreed to re-evaluate the geology at drilling sites after puncturing aquifers in some locations, disturbing the water supplies of some residents whose private wells draw on those aquifers. Sunoco also said it would file reports of its plans to the Pennsylvania Department of Environmental Protection.

The re-evaluation of HDD sites, as agreed to by Sunoco, includes sites where there was an “inadvertent return” of drilling fluid, the term used by the company for a spill. The company said it would consider data that are specific to each drilling site, and conduct extra geotechnical evaluations such as seismic surveys and ground-penetrating radar as appropriate. The re-evaluations will be certified by a professional geologist with relevant experience, the agreement said.

The deal was made with three environmental groups who were seeking to extend a two week drilling ban at 55 active sites that the judge imposed after dozens of spills of drilling fluid-tainted private water wells and flooded wetlands in some places along the 350 mile pipeline route.

The 25 July order was the biggest setback so far to construction of the more than US$2.5 billion pipeline, which will carry natural gas liquids from the Marcellus Shale of southwest Pennsylvania to an export terminal at Marcus Hook, near Philadelphia. It followed another judge’s order to halt construction in West Goshen Township, Chester County, and comes amid a legal challenge to the project’s claimed status as a public utility.

The pipeline project released a clay slurry made of bentonite and water roughly 90 times over a three month period during HDD operations. The releases clouded more than a dozen private water supplies, seeped through bedrock and muddied wetlands and lakes.

The agreement, posted online late yesterday afternoon by the state Environmental Hearing Board, requires Sunoco to re-evaluate plans for horizontal drilling and to submit the plans for approval to the Pennsylvania Department of Environmental Protection. DEP will have 21 days to review the plans.v

Sunoco, which is owned by Energy Transfer Partners LP of Texas, is building the cross-state Mariner East 2 pipeline largely along the same route as the smaller Mariner East 1 pipeline, which went into service more than two years ago.

The company decided to use the horizontal drilling method to install the new pipeline beneath large streams, rivers, and highways, and under densely developed areas, to reduce the nuisance caused by cutting an open trench.