I believe the extreme volatility of heavier than air methane, butane & ethane gases in Mariner East Pipeline combined with Chester County's limestone geology of underground caverns make an explosion that will kill people a likelihood. Not a possibility.

"WEST WHITELAND TOWNSHIP, PA — A sinkhole 23 feet long by 10 feet wide by 6 feet deep opened up along the Mariner East easement in West Whiteland Township on June 4 in a situation that a drilling industry publication called "not good.”

There are two active Mariner East Highly Volatile Liquids (HVL) pipelines on either side of the sinkhole. It was one of several sinkholes to open this year in this area of Mariner East construction behind Exton Library and near Meadowbrook Manor.

The Marcellus Drilling News, a drilling industry website, reported to others in the business today "Another sinkhole has appeared in Chester County at a Mariner East 2 (ME2) Pipeline construction site. This time it's located near the Chester County Library. The sinkhole is approximately 23 feet long, 10 feet wide, and six feet deep. It runs between two existing (older) pipelines that actively carry petroleum products. Not good.”

 Sinkholes In West Whiteland Twp. Shut Down Pipeline

Sinkholes appeared near Meadowbrook Manor after water overwhelmed a Sunoco pipeline groundwater pump at the pipeline work site.

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"What can Sunoco do if the problem is serious? From what I hear, the drill at the front of the auger is broken and has become stuck in place. That’s a problem. It might be possible to dig down to the broken drill, retrieve it, and replace it.  If that were simple to do, it would already have been done. I have to assume it can’t be done, perhaps because of difficulties in reattaching the new drill to the front of the auger. Even if this approach were to be attempted, it would be very difficult to keep ground water out of the hole. I believe that the present location of the drill is below the local water table.

Another option might be digging a huge pit to expose the entire casing, cutting the casing into pieces, and pulling the pieces out with a crane. That would require operating heavy equipment in close proximity to the other operating pipelines in the easement, a dangerous proposition. And again, ground water would be a massive problem. Once the casing and auger were removed, the pit could be filled and Sunoco could try again.

Abandoning the partially-installed casing and starting again nearby would require finding a new drill path in a 50-foot easement that already has several active pipelines in it. It seems unlikely that a practical alternative path for such a large casing could be found.

What about rerouting? Finally, Sunoco could find an alternative route for this section of Mariner East (as the DEP is asking Sunoco to do at Marsh Creek). That would add a year or more to the project. And finding a new route in a densely-populated area like Exton would be very difficult."

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DRAGONPIPE DIARY

Sunoco has a problem at Valley Creek in Exton

View all posts by galex49 April 18, 2021

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I believe the extreme volatility of heavier than air methane, butane & ethane gases in Mariner East Pipeline combined with Chester County's limestone geology of underground caverns make an explosion that will kill people a likelihood. Not just a possibility.

Imagine this Carlsbad Caverns room full of explosive gasses.