Mariner East 2: What are natural gas liquids, and what happens if they leak? | StateImpact Pennsylvania Skip Navigation

Mariner East 2: What are natural gas liquids, and what happens if they leak?

  • Susan Phillips
  • Tom Downing

The pipeline will carry volatile propane, ethane and butane, which has raised fears of many who live near it — even though explosions are rare. As part of StateImpact Pennsylvania’s “Mariner East 2: At what risk?” series, we put together this video to explain what those substances are and how they act both inside the pipeline and if they got out, and how you should respond if there’s a leak.

As part of the “Mariner East 2: At what risk?” series, this StateImpact Pennsylvania video examines the natural gas liquids that flow through the pipeline and what happens if they leak — something that could be caused by:

  • Welding failures
  • Material defects
  • Corrosion
  • Shifting land exposing the pipe

In 2017, about 1,000 gallons of natural gas liquids leaked from the Mariner East 1 in Morgantown, Berks County. It was discovered by a resident who noticed discolored grass. The leak did not result in an explosion.

In September 2018, a leak from a gathering line carrying a mixture of hydrocarbons including methane, ethane and butane resulted in an explosion, with one house burning to the ground. No one was injured.

The Mariner East 1 pipeline has experienced three leaks since 2014. Those leaks did not result in any explosions.

This story is part of the series “Mariner East 2: At what risk?” Other stories in this series:

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