Permian Oil and Gas Sites Continue to Emit Massive Amounts of Methane Underscoring Importance of Strong EPA Rules

Leaks at many smaller wells, flare stacks and midstream facilities continued indefinitely – even after operators were notified of problems

December 14, 2021
Matt McGee, (512) 691-3478,

(Austin, TX) An aerial survey of nearly 900 different oil and gas sites in the Permian Basin reveals that massive methane emissions at many sites recurred for months on end, often even after operators were notified of problems.

Methane is an invisible, yet very potent greenhouse gas emitted from oil and gas facilities alongside harmful pollutants linked to cancer, asthma and other illnesses.

This survey was conducted as part of EDF’s PermianMAP initiative, which has been measuring and reporting information about oil and gas methane emissions from the nation’s largest oilfield since 2019.

Widespread emission events across sources

This latest research – conducted via helicopter between Nov. 12 and Nov. 21 of this year – detected significant plumes of methane from about 40% of the roughly 900 sites surveyed.


  • About 14% of all emission events came from malfunctioning flares.
  • 30% of surveyed pipelines had detectable emissions. 
  • Roughly half of all surveyed midstream facilities - which process, pressurize and help transport gas - had detectable emissions.

Recurrent high emissions, including from smaller wells

This is the eighth survey in which researchers mounted a special infrared camera to a helicopter to find high-emitting sites. The helicopter revisited nearly all of the sites where emissions were previously observed and found that nearly half still had recurring emissions. 

In addition to studying how often emissions persist over the course of several months, researchers examined the rate at which emissions recur within a week – specifically looking at smaller well sites where emissions are frequently underestimated.

Here, researchers observed that a third of smaller well sites had large emissions that persisted for days, with leaks often coming from different pieces of equipment at different times.

See this video for the latest methane emissions footage.

Significance for EPA’s proposed methane rules

Last month, the Environmental Protection Agency proposed new regulations to reduce methane emissions from the oil and gas industry. The proposed rules would require operators to regularly find and fix their emissions – a requirement not currently in place for oil and gas facilities built before 2015.

However, under the current proposal, operators of smaller leak-prone facilities would only be required to conduct a one-time inspection of their well sites. This study suggests a single inspection will not be sufficient to reduce total methane levels, since there are over half a million of these wells across the country, many with recurring leaks that could go permanently undetected.  

“There are dozens of reasons why a site might be emitting high levels of methane. The only way to know what’s going on and to ensure things are operating properly is to regularly check sites for problems that lead to massive pollution,” said David Lyon, Senior Scientist with Environmental Defense Fund. “Our research has consistently shown that leaks can and do happen at all types of facilities – including smaller, leak-prone wells – and the best way to control emissions is to find and fix them.”

The EPA is accepting public comments on its methane proposal through Jan. 31. Comprehensive and protective EPA standards will be a central component of the Administration’s goal to reduce 30% of all methane emissions by 2030.

“The EPA has a real opportunity to change the game and make a meaningful dent in our methane pollution,” said Jon Goldstein, Senior Director of Regulatory and Legislative Affairs at Environmental Defense Fund. “This research makes clear that the agency must tackle frequent, large emissions from smaller wells if we’re going to have a shot at achieving our climate goals and protecting communities from air pollution.”

See the complete survey data here.

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