We now know, thanks to information from a whistleblower, that a sinkhole caused by pipeline construction along a busy road in suburban East Goshen Township, Chester County, could easily have caused a major disaster. The sinkhole threatened the integrity of operational pipelines carrying highly volatile explosive materials.  Sunoco was able to cover up the incident for six months, and we might never have known if the whistleblower hadn’t stepped forward. The Clean Air Council is suing Sunoco over this issue.

The map below shows the approximate location of the sinkhole, near Bowtree Drive on Route 352. Two active Mariner East pipelines run in the easement here, and two more are under construction. The whistleblower, a professional geologist working for Sunoco, was concerned that if the sinkhole caused the supporting earth to drop away from under one of the pipelines, the pipeline might rupture. As the whistleblower pointed out, that is similar to what happened in the Beaver County explosion on Sunoco’s Revolution pipeline.

This is exactly the sort of situation that those of us concerned about Mariner East safety issues worry about, and if it involved Mariner East it would be far more dangerous than the Beaver County explosion, which involved natural gas. Natural gas is lighter than air and disperses readily; the highly volatile liquids carried by Mariner East (ethane, butane, and propane) are heavier than air and pool along the ground, forming a flammable vapor cloud.

Approximate location of the sinkhole. The circle indicates areas that could be within the flammable cloud created by a rupture of the 12-inch pipeline.

Who would be endangered? In the event of a Mariner East rupture at the Bowtree site, if the cloud didn’t immediately ignite, it would cover a large area of East Goshen Township until it finally reached a source of ignition. The area threatened by this type of event depends on several factors, such as the size of the pipe, the size of the release, and the weather.

The circle on the diagram represents the areas that the cloud might reach in the case of a rupture of a 12-inch pipeline on a day with light wind. The cloud could extend about three-tenths of a mile. There are over 170 houses within the circle. Depending on which way the wind is blowing when a rupture occurs, 30 or 40 of them could be engulfed by the flammable cloud and burn.

If Sunoco completes the 16-inch and 20-inch pipelines here, those two pipelines would also be vulnerable to rupture. In that case, the area affected would be far larger, stretching out to well over a mile from the rupture location. It is worth emphasizing that, although Sunoco filled in the sinkhole, we don’t know what’s happening underground. The earth may still be unstable, which means that the danger from a rupture is not over—and it still won’t be over, even when construction is complete.

East Goshen Township will act. Once the township recognized the extent of the risk that Sunoco was attempting to hide, they decided that action was necessary. The following announcement was posted on the website:

“The Board of Supervisors and the EGT Pipeline Task Force were recently made aware of a whistleblower complaint involving the Sunoco/ET Mariner pipeline in East Goshen Township. This matter involves a dispute regarding geophysical surveys required for Horizontal Directional Drilling conducted along Route 352 (North Chester Road). The Board of Supervisors takes this matter very seriously and is conferring with legal counsel to determine next steps.”

It is my understanding that this situation is prompting other jurisdictions to consider their own legal action or to join in whatever action East Goshen decides to take.

It’s not just East Goshen, it’s all across the state. Sunoco’s construction has triggered sinkholes at many locations that we know about besides East Goshen. And if Sunoco has made a general practice of covering up these events, as the whistleblower suggests, there could be many more sinkhole locations in less-populated areas that we don’t yet know about. There may well be the potential for the same kind of rupture at many locations across the state.

This coverup is one more reason for shutting this pipeline system down until it can be determined whether it can be operated safely.

Here’s what you can do. First, contact your elected representatives and tell them you support their efforts to shut down the pipeline. Then, make a contribution to help the Safety 7 case before the PUC. The hearings in this case are wrapping up, but there will not be a decision until early next year. In the meantime, funds are urgently needed to pay expert witnesses and court fees.

Please contribute! Any amount, small or large, is a help. Details are on the Safety 7 GoFundMe site here: