“Greenhouse gas” and “climate change” have been buzzwords for decades, and these problems aren’t disappearing any time soon (though emissions have dropped 5 percent since 2010, according to the Environmental Protection Agency). But what if we could cut down on methane emissions—a greenhouse gas that’s about 30 times more effective at trapping solar heat over 100 years than carbon monoxide—just by getting rid of things we don’t even use anymore?
A team of scientists from Stanford University, Princeton University, the Ohio State University and the Lawrence Berkeley National Laboratory found that the 475,000 to 700,000 abandoned gas and oil wells in Pennsylvania (the state with the longest history of gas and oil development in the U.S.) are emitting 50,000 metric tons of methane per year, about 5 to 8 percent of the state’s greenhouse gases.
“Five to 8 percent isn’t trivial,” Stanford’s Rob Jackson, an author of the study, said to Rewire. “These are wells that keep emitting year after year and decade after decade.”
But a few of these are “super emitters,” abandoned natural gas wells left open and unplugged that are pumping out methane at a much higher rate. These major leaks are happening across the country and are likely responsible for 40 to 90 percent of the U.S.’s methane emissions, according to another Stanford, National Renewable Energy Laboratory and Colorado State University study.
“You could seal the vast majority of emissions just by addressing 5 to 10 percent of the wells,” Jackson said.
This means that instead of trying to identify and plug hundreds of thousands of methane leaks across the country, which would be cost prohibitive, companies and state governments can focus on the super emitters. Plugging a well involves pouring cement into it to create a series of different barriers.
“Technically, we know exactly how to fix them,” said Stanford’s Mary Kang, another researcher on the team, to the university. “The problem is it’s not cheap to do so.”
“We’re underinvesting in the legacy issues in the oil and gas industry—most states don’t have enough funds set aside to deal with… issues like plugging oil and gas wells,” Jackson said. “That means the number of unplugged oil and gas wells is rising rather than falling.”
The researchers determined through studying the way the super emitters leak that it might not be necessary to fully plug them to stop the emissions, which will cut costs. It’s also cheaper to find super emitters than it is other methane leaks—less sensitive technology is needed to find such big methane outputs.
“States are already spending millions of dollars a year to plug abandoned wells,” Jackson said. “Our hope is that our data will be useful for helping states decide how and where to spend their limited money.”
But first, “we need a lot more data in many more locations,” he said. “This is an issue across the United States and it’s an issue in other parts of the world, too.”