Energy. Environment. Economy.

Study: Abandoned wells could be significant source of greenhouse gas

An abandoned oil well in the Tamarack Swamp, Warren County.

Susan Phillips / StateImpact PA

An unplugged oil well in the Tamarack Swamp, Warren County.

A new study out this week shows that Pennsylvania’s abandoned oil and gas wells could be a leading source of greenhouse gas emissions.

Pennsylvania is littered with old oil and gas wells that date back to the 1860’s. Unmapped and unmonitored, these wells can turn into pollution pathways for oil, gas and brine. About 12,000 of an estimated 300,000 wells have been found and plugged. But the peer reviewed report out this week in the Proceedings of the National Academy of Sciences, shows even the plugged wells are leaking methane, a potent greenhouse gas. Mary Kang is the lead author on the study.

“Surprisingly all the plugged wells that we measured emitted methane. We found that emissions varied by order of magnitude,” said Kang.

Kang’s research shows that both plugged and unplugged wells could be contributing significantly to global warming. Although she only tested 19 wells, her results showed that the abandoned wells could be spewing just as much fugitive methane as current oil and gas production in the state. Yet neither the federal Environmental Protection Agency, or the state keeps track of these emissions. And data and history about these wells was hard to come by. Only one of the 19 wells she found and tested was recorded in the state’s database on abandoned and orphaned wells.



  • Sue

    FINALLY! I have been asking about all those old holes for years without any response!It always seemed that our Swiss cheese of a state would be leaky as hell, but nobody would document it.

    Thank you Mary Kangaroo et al!

  • Sue

    Damn spellcheck!Mary Kang

  • Jack Wolf

    I’ve tripped over a few of these abandoned wells, and one in the Allegheny National Forest no less.

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