Parents of Twin Valley Middle and High School students are probably aware of the pipeline construction that has been going on near their kids’ schools. The Dragonpipe (Mariner East 2 pipeline) goes right by the two schools. I’m sure it has been hard to ignore the equipment and the noise.

But how many parents understand the risk to their children from this project if there were to be a serious accident? Do they understand that in the event of a total pipeline rupture (admittedly unlikely, but possible) both schools could be surrounded by a lethal, flammable cloud? That after an explosion, access to the Middle School by first responders could be blocked for hours while the gas remaining in the pipeline burned off? That this pipeline is far more dangerous than any other pipeline in the area? These are things all parents need to know, and they need to tell their representatives and regulators to do something about it.

The image below shows the pipeline right-of-way and the area that could be covered by a cloud of flammable gas if there were to be a total rupture of the pipeline. (A smaller leak would cover less area, but it could still surround both schools.) If a cloud like this caught fire, it would put over 2,000 students and their teachers at risk (about 1100 in the Middle School and 1000 in the High School).

twin valley schools vapor cloud 12-9-18
The red line in this image is the Mariner East right-of-way. It passes close to Twin Valley Middle School and High School. The light-colored oval is the area that could be covered by a flammable vapor cloud in the case of a pipeline rupture. If it then ignited, everyone in the cloud would be killed.

The worst-case scenario. The cloud shown here is a worst-case event: a total rupture of the 20-inch pipeline on a relatively calm day with a gentle wind blowing toward the schools. The exact boundaries of the cloud would shift with the shifting wind. The size of the cloud is taken directly from the Mariner East risk assessment commissioned by Delaware County Council. If the gas were to escape for about 10 minutes before finding an ignition source, the entire area of the cloud would burn in a few seconds in what is called a “flash fire”. Anyone outdoors at the time would be killed by the fire.

Being indoors might give limited protection from the flash fire, but it would not offer protection from the lethal shock wave produced by the explosion.

After the flash fire, even if the operator shut the valves to isolate the damaged stretch, the gas would continue to exit the pipeline until it had all emptied, a process that would take many hours. As it left the pipeline, the heat would be so intense that the gas would catch fire immediately. The resulting fire (called a “jet fire”) would be like an enormous blowtorch. While smaller than the flash fire, it would be much hotter.

Given the fact that there is only one way in to the Middle School (Clymer Hill Road), the location of the jet fire could have an important impact. If it blocked Clymer Hill Road, there would be no way for first responders to reach the Middle School to help those who had survived the flash fire. Depending on exactly where the jet fire was, it could impede access to the High School as well; and for many hours, it would be too intense to approach. The only way to extinguish a jet fire is to let it burn itself out.

Could this really happen? I know some readers will be skeptical about the possibility of this type of accident. It is certainly unlikely, but not impossible. There have been comparable accidents before (although fortunately none were near a school or a population center). The size of the cloud shown above (and the consequences of igniting it) is based on information from the risk assessment that Delaware County Council recently commissioned. You can read about the details of the process that went into the creation of the image in my blog post about “How I model a local pipeline accident”.

This is not like other pipelines. Perhaps someone has said to you, “We have lots of natural gas pipelines around here. What’s one more?” Let’s be clear. First of all, this is not a natural gas pipeline. It will carry “natural gas liquids” which are actually highly-compressed flammable gases that are byproducts of fracking. The only connection they have with natural gas is that they emerge from wells that also produce natural gas. They are far more dangerous than natural gas, because they are much more concentrated and because they are heavier than air and form a flammable cloud along the ground. The details are in my blog post called “Yes, this pipeline is much more dangerous. Here’s exactly why.” I encourage you to read it, and give the link to your skeptical friends.

As a final insult, almost none of this dangerous material is for US consumption. It is being shipped to Europe to make plastic. Can we afford to risk our children’s lives for this?

Contact your elected officials and tell them this project needs to be stopped. Governor Wolf has emergency powers that would let him stop it immediately. The Public Utility Commission could also act. Let them hear from you!

Here’s how:

  • Write to Governor Wolf, who has the power to stop this pipeline if he wants to. You can use this contact form:
  • Write to your state senator and representatives (who can sponsor legislation and hold public hearings to show the public how dangerous this pipeline is). Don’t know who they are or how to contact them? Get that information from this site:
  • Get your school board or township to intervene in one of the complaints concerning this pipeline with the Public Utility Commission. Intervening isn’t difficult or expensive. It doesn’t obligate you to take an active role in the case, but it does add weight to the public opposition.