Sunoco has submitted a response to the DEP’s questions about the Sunoco plan for installing the 20-inch pipeline through the area of the Exton bypass and Lisa Drive. The deadline for commenting is Monday (Sept. 23). Instructions for commenting are at the bottom of this post.
The text of Sunoco’s recent response to the DEP’s questions is here.
The full text of Sunoco’s original proposal is here.
Sunoco’s response makes an evasive attempt to respond to the DEP’s questions concerning what happens if the new borehole hits grout from previously filled depressions.
The original proposal involves over 2000 feet of open trench work, and over 800 feet of “direct bore” tunneling. It is the direct bore that raises the most concern. Its route runs alongside ME1 and, for most of the route, also alongside the 12-inch “workaround” pipeline that is part of what Sunoco is calling “ME2”. Both of these are in operation, carrying highly volatile explosive materials.
The thrust of the DEP questions is: will the grouting material used to fill the Lisa Drive sinkholes be disturbed during boring? If the grout is hit by the boring equipment, that could stress the operational pipelines, potentially triggering a leak. (I am using the terms “grout” and “fill” interchangeably, which is what Sunoco does in its responses.)
Where is the underground fill? In its first question, the DEP asks for a figure showing the location of the fill, and asks that it not be disturbed. In response, Sunoco has submitted a figure showing where the sinkholes appeared, and notes: “As shown, neither the direct bore profile, nor the receiving pit intrudes into the fill locations.”
But the location of the sinkholes themselves is not what the DEP requested. They want to know where the fill went. During the period that the holes were filled, dozens of cement-truck loads of grout were dumped into the underground voids that led to the sinkholes. The DEP is asking where that grout went, and Sunoco is not answering.
Tell the DEP to insist on detailed information about the location of the grout.
What is the contour of the underground fill? In its second question, the DEP asks for a “resistivity survey” to determine the contours of the grout underground. In response, Sunoco provides a letter from a company, Gannett Fleming Quantum Geophysics, explaining why a resistivity survey would not work very well in an area containing conductive metal (i.e. underground pipes). Instead, Sunoco assures the DEP that the grout is all between 70 feet and “15-20” feet underground, and therefore it is below the profile of the bore hole in the Lisa Drive area. (In fact, near its exit point the bore profile is within 19 feet of the surface, so the grout would have to be at least 20 feet, not 15 feet, underground to avoid disturbance.)
But Sunoco provides no evidence that the grout is that far below the surface. In fact, the grout was poured into the holes from ground level, and some of it certainly remained near the surface.
Tell the DEP to insist on actual evidence that all the grout is deeper than 20 feet; otherwise, the direct bore could hit it.
What happens if the bore encounters grout? The DEP’s third question is what Sunoco’s plans are if the direct bore encounters the grout.
This question is not answered. Sunoco’s response is that the cuttings from the boring machine are disposed of in a licensed landfill. The DEP was not asking about the cuttings, it asked what “contingencies” there were if the grout were hit in the boring process. Apparently, there are none.
Tell the DEP to require a contingency plan for what Sunoco will do if the direct bore hits the grout.
There are many other questions about Sunoco’s original proposal that are unanswered in this document. If you would like to pursue them, please read my June blog post on this topic.
Everything I complained about then is still a problem.
I urge you to submit your comments to the DEP. It just takes an email. This plan has the potential to damage active pipelines and cause leaks. Tell the DEP that Sunoco should be required to do better. Please submit your comments immediately.
Feel free to make use of the information in this blog post in the comments you submit. But it is more effective if you use your own wording rather than simply copying mine. The DEP needs to hear from you!
Email your comments to: Raemail@example.com
Mention the ID number for this section of the pipeline, which is PA-CH-0236-0000-RR. The deadline is Monday, September 23.
While you’re at it, why not copy your local state representative, state senator, and Governor Wolf? They need to hear your opinion too.