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

  • Susan Phillips
  • Tom Downing

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: