Thousands of fracking wells in Pennsylvania 'may be leaking methane'

Bobby Magill in the Guardian (UK) via Climate Central: A study of abandoned oil and gas wells in Pennsylvania finds that the hundreds of thousands of such wells in the state may be leaking methane, suggesting that abandoned wells across the country could be a bigger source of climate changing greenhouse gases than previously thought.

The study by Mary Kang, a Princeton University scientist, looked at 19 wells and found that these oft-forgotten wells are leaking various amounts of methane. There are hundreds of thousands of such oil and gas wells, long abandoned and plugged, in Pennsylvania alone, and countless more in oil and gas fields across the country. These wells go mostly unmonitored, and rarely, if ever, checked for such leaks.

A growing list of studies conducted over the past three years has suggested that crude oil and natural gas development, particularly in shale formations, are significant sources of methane leaks — emissions not fully included in US Environmental Protection Agency greenhouse gas inventories because they are rarely monitored. Scientists say there is inadequate data available for them to know where all the leaks are and how much methane is leaking.

...So when abandoned oil and gas wells — possibly hundreds of thousands of them in Pennsylvania alone — that are not currently included in any federa
l estimate for total US greenhouse gas emissions are found to be leaking methane, the implications could be significant.

Kang directly measured leaks from the abandoned wells and found that all 19 wells in the study tested positive for methane leaks, some more than others. She found that overall, the wells leak so much methane that if leaks from all the abandoned wells in Pennsylvania are added up, the leaks could account for between 4 percent and 13 percent of human-caused methane emissions in the state.

But because of significant uncertainty about the total number of abandoned and plugged wells that exist in Pennsylvania, more study is needed to fully understand how common leaking abandoned wells are in the state and how much methane they may emit....

A fracking site in Warren Center, Pennsylvania, shot by Ostroff Law - Fracking Lawyer, Wikimedia Commons, under the Creative Commons 3.0 license