Methane is colorless and odorless. But it’s a powerhouse in the way it contributes to global warming. In the atmosphere, it’s more than 100 times more potent than carbon dioxide.

Now, after the growth of a natural gas production operation commonly known as fracking, the United States is producing more methane emissions than any country in the world. And in a complaint submitted to the Environmental Protection Agency’s Office of the Inspector General on Wednesday, a small North Carolina watchdog group argues persuasively that the government might not know how much is released into the sky as a result of drilling and storage of gas extracted from shale deep under ground.

The 68-page complaint by NC Warn accuses the EPA of allowing untold levels of methane into the atmosphere by allowing oil and gas companies to monitor emissions with a pricey device that’s faulty. The group says in its complaint that the agency knows the $20,000, backpack-sized Bacharach Hi-Flow Sampler doesn’t work well because the man who invented the technology that inspired it blew a whistle years ago.

The inventor, Touché Howard, also took his concerns to a respected researcher who used the device as one way of measuring methane emissions for a major study undertaken on behalf of the Environmental Defense Fund, which hoped to answer the question of how bad it is. In spite of Howard’s objections to David Allen, a professor at the University of Texas, the study found that methane emissions were lower than EPA estimated at completed wells and higher around valves and equipment used to control routine operations at sites.

For that, NC Warn accused Allen of fraud. “It appears that the goal of the [University of Texas] team was not to critically examine the problems but to convince EDF …that no problems existed,” NC Warn claims in the complaint. “We believe Mr. Howard was specifically prevented from providing input because the … team knew that he would be able to show that their counterarguments were faulty and the resulting studies scientifically invalid.

“Meanwhile, the faulty data and measuring equipment are still being used extensively throughout the natural gas industry worldwide.”

For the university, those were fighting words that drew a strong rebuke. “David Allen is a scientist of the highest integrity and his peer-reviewed studies were overseen by scientific advisory panels, published in top-tier journals and have been open to public scrutiny for several years,” a university spokesman shot back in a statement.

Allen stood by his work in his own defense. “The instrument was used for only a subset of the measurements that were made,” he said, explaining that there are other ways to measure methane, and that the readings of the Bacharach device were double-checked. “All of these systems would have had to fail, simultaneously, and only at certain types of sites with the conditions that are claimed to produce the equipment failure, for our measurements to have been impacted.”

And the EDF also backed him in a diplomatic response from Mark Brownstein, vice president of the climate and energy program at EDF, tried a diplomatic approach. “I think that it’s always useful to have yet another set of eyes review scientific work to check to make sure that it’s been done well,” he said. But “even if you believe this device gave you false readings,” he added, “there have been 20 studies looking at this from a variety of different of ways.”  

Methane emissions can be measured from the sky with instruments attached to the wings of airplanes, he said. “As to whether this complaint has larger implications for our understanding of methane emissions or steps we should be taking, it doesn’t have much of an impact, given the large body of other studies that have been done to assess these emissions.”

Finally, EPA said its understanding of the volume of methane emissions is evolving, and estimates “are based on the best data available at the time of their development.”   The effort to understand methane emissions from oil and natural gas industry, “which is the largest industrial source of methane emissions in the U.S.” is part of the agency’s Greenhouse Gas Reporting Program attempt to collect “significant new data on methane emitted in the oil and gas sector.”

But NC Warn isn’t backing down, and neither is Howard. “As long as someone prestigious like Dr. Allen says [underreporting of methane] did not occur in my research, then it’s hard to say how widespread this problem can be,” Howard said.

The watchdog group casually mentioned in its complaint that 90 percent of the $18 million that was paid for several EDF reports came from the natural gas industry, but the large majority of the reports had nothing to do with methane, Brownstein countered. EDF added that NC Warn’s accounting is dead wrong: the oil and gas industry contributed only a third of the funding, a spokesman said, with the balance coming from philanthropic organizations. “We have been fully transparent about these details,” the green group said.

Here’s what’s at stake, according to Robert Warren Howarth, a professor of ecology and environmental biology at Cornell University who is considered to be one of the nation’s foremost experts on methane gas. “Emissions have been rising, in large part from the development of shale gas and shale oil — a huge contrast to what the EPA has been saying,” he said.

Howarth pointed out that the United Nations Intergovernmental Panel on Climate Change said methane emissions have the most virulent effect on climate change. In the Paris climate agreement, which the U.S. joined, the panel said it can’t reached its goal of keeping global temperature increases at or below 3.6 degrees Fahrenheit by 2100 if those emissions aren’t lowered.

It’s time to listen to Howard and revisit the study that found a lower level of methane emissions, given what’s known about the quirks in the device that monitored them. “EDF has made a big effort over the past five years to better characterize what the methane emissions are,” Howarth said. “Touché Howard tells me he was raising concerns going way back and people were ignoring him. It’s embarrassing to have to backtrack on something you’ve done, especially if you’ve said what a great study it is and an important study.”

Howard’s views have weight because he designed the technology used in the monitoring device in the early 1990s. He sold it when he retired in 2003 and eventually Bacharach Inc. bought and modified it. During a test of methane emissions in 2013, Howard noticed that a sensor in the device failed to properly detect methane when other hydrocarbons were present. A cross check confirmed the failure, he said.

He reached out to Allen and claims he was rebuffed. Howard said he sometimes can’t sleep for worrying about a catastrophic result from underreporting methane emissions that has nothing to do with global warming. 

“I worry about something catastrophic, like an explosion,” he said. “I think the implications are enormous. If people think emissions are much lower than they actually are, there will be less urgency on addressing reductions.

“All this stuff is pretty basic. If we can’t get the easy stuff right, what does that say about trying to understand the really tough stuff that’s going on, like climate modeling and extrapolations?”

This report has been updated