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“Orphaned” wells are oil and gas wells that have been left behind by their owner and are no longer in service.
That doesn’t mean they’ve been plugged or cleaned up, though. They can spew pollution into our air, water, and atmosphere, harming people’s health and accelerating climate change. These wells are all over the country in building basements, farm fields, forests, waterways, and around homes. They may even be in your neighborhood.
The Environmental Protection Agency (EPA) estimates that there are as many as 1.1 million unplugged or abandoned oil and gas wells that are emitting methane and other toxics comparable to the pollution of 1.5 million cars. Estimates of additional undocumented orphaned wells range from the many hundreds of thousands to several million in the U.S. alone. Many states are fast at work confirming the location and legal status of suspected orphaned wells, as well as tracking plugged wells. Pennsylvania has—by far—the largest population of orphaned wells in the United States, not all of which have been located. Numbers will continue to fluctuate as more states work on finding orphaned wells.
An old pump jack in in Gainesville, Texas.
Why do orphaned wells exist?
Oil and gas operators are currently required to seal wells at the end of their productive lives, but the previous 170 years of oil and gas development have left a massive inventory of inactive and unplugged wells nationwide. Instead of plugging the well and restoring the surrounding land, oil and gas companies used to walk away and leave behind a legacy of unplugged wells that could emit pollution. Since orphaned wells no longer have an identifiable owner, they become the responsibility of the government—federal, state, or Tribal—to clean up, often at taxpayer expense. Even now, some companies still walk away from wells, in the case of bankruptcy or other market disruption, which leaves millions of dollars in cleanup costs to states.
Orphaned wells are often confused with abandoned wells, but they’re not the same thing. Abandoned wells may have identifiable owners who can be deemed responsible if one is found unplugged or in disrepair and leaking. A well that requires a permit to dig will usually have a trackable owner. But if that business no longer exists or, say, the owner is deceased, that’s when an abandoned well becomes an orphaned well.
Why should we care about them?
Orphaned wells represent a significant source of methane emissions in the U.S., contributing accelerated warming from greenhouse gas emissions to the climate crisis. A United Nations report found that cutting methane emissions is the “strongest lever” humanity has to slow climate change by 2030 and keep warming below catastrophic levels. Orphaned wells also put the safety of those who live nearby at risk. They can leak oil, gas, and other toxic chemicals into our air, soil, and water. Children who live, learn, and play near orphaned wells and their pollution are especially vulnerable to harm.
Map: Environmental Defense Fund
Orphaned wells and health
There’s no simple way to determine how dangerous an orphaned well is; it depends on how much any given well may be leaking. People who live near orphaned wells are at an increased risk of exposure to air pollution, including methane, volatile organic compounds (VOCs), and other toxic chemicals as well as contaminated groundwater and odor. One study specifically found benzene along with other toxic pollutants that can cause cancer and damage the nervous, immune, and respiratory systems in emissions from abandoned wells in Pennsylvania. Benzene is also associated with low birth weight.
Many orphaned wells across the country are close to people’s homes, like this one in Pennsylvania. Photo: Pennsylvania Department of Environmental Protection.
The link between orphaned wells and community impacts
Orphaned wells are located all over the U.S. and can often be found where there was early oil and gas extraction that predates regulations and reporting requirements, most prominently in the Southwest (NM, TX, OK) and the Ohio River Valley (OH, PA, WV). People living near oil and gas wells are especially vulnerable to the air pollutants they emit, and the air quality health burdens of oil and gas operations are not equitable. Millions of people in the U.S. live less than a mile from an orphaned well and a disproportionate percentage of those people are Black or Latino.
An orphaned well in St. Martin Parish, Louisiana. Photo: Louisiana Department of Energy and Natural Resources.
There are solutions to the problem of orphaned wells.
Plugging wells—once they’re located—will protect our environment, climate, and communities. Cleaning up orphaned wells is expensive, which has historically been a large barrier for state, federal, and Tribal agencies.
But millions in funding specifically allocated for plugging orphaned wells through the Infrastructure Investment and Jobs Act has been distributed to states, and the work is underway.
More work lies ahead, both in identifying additional orphaned wells and cleaning them up. Individuals can help identify wells. If you happen to smell or otherwise find an orphaned well near where you live, report it to your local environmental agency to have someone come plug and tag. And join Moms Clean Air Force to continue to pressure our elected officials to provide needed tools to locate, catalog, and clean up orphaned wells nationwide.
Learn more about Moms’ work on methane.
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Updated: February 2025