This Five-Mile-Long Cloud of Methane Was Spotted Over Wyoming

It all started with an apparent mistake. Alarms were triggered at Tallgrass Energy's Douglas Gas Plant in Wyoming after high oxygen levels were detected following a maintenance project. The operator told regulators that a total of about 2.1 metric tons of methane were released in five separate safety releases.

A satellite passing over the US state observed a methane cloud 4.6 miles long emanating from the location. Scientists estimated that the gas was being spewed at a rate of 76 to 184 metric tons an hour. However, because the researchers who studied the data couldn’t verify how long the release lasted, they said it was likely that the total amount of methane spewed was far higher than what was reported.

The International Methane Emissions Observatory (IMEO) has released the findings of its geospatial scientists, which cast doubt on the volume of emissions reported by the operator of a methane-emitting facility.

According to the IMEO, it is highly unlikely that the volume reported by the operator could account for the emissions rate observed by the satellite. Manfredi Caltagirone, head of the IMEO, summarized the findings of the study, saying that the data collected by the satellite "paints a very different picture" of the facility's emissions.

Methane is a powerful greenhouse gas, with over 80 times the warming power of carbon dioxide in its first two decades in the atmosphere. Cutting methane emissions could have a big impact on slowing climate change.

Fossil fuels are a significant source of methane emissions, second only to agriculture. However, leaks and releases from oil and gas operations are relatively easy and inexpensive to fix. Operators have a financial incentive to minimize emissions, as they can sell the extra gas they capture to offset the cost of repairs and upgrades.

A new generation of high-resolution satellites is revealing that methane emissions from oil and gas facilities around the world routinely go unreported or under reported, with operators sometimes unaware of how much gas is escaping. Kuwait's state oil producer said its monitoring systems never registered a three-week methane leak spotted by satellite last year, while New Mexico authorities said earlier this month they were investigating an undisclosed release near APA Corp facilities.

The concentration of methane in the atmosphere is 2.5 times higher than it was during pre-industrial times.

As buyers increasingly seek out producers with cleaner records, companies that can't control their emissions risk playing a diminished role in the energy transition. A growing focus on ESG credentials also raises pressure on investors to shun companies that aren't doing more to minimize their impact on the climate.

As governments look for ways to meet their climate goals, the issue of methane emissions is beginning to draw regulatory scrutiny. One hundred and fifty countries have pledged to cut methane emissions by at least 30% by the end of the decade from 2020 levels.

The IMEO is the most high-profile public effort to date to identify and attribute the world’s methane emissions through satellite observations. Through its Methane Alert and Response System, which was launched at COP27, the group aims to engage with governments and operators to curb methane emissions.

IMEO's estimates of Wyoming's emissions were based on an observation made at 10:43 a.m. on December 7 by NASA's Landsat 9 satellite. The location and timing of the observation match a release Tallgrass Energy Partners, LP reported to regulators in an email sent on December 8. Bloomberg News obtained the email through a public information request.

Tallgrass Energy reported five emergency releases of methane in an email on December 6 and 7. One of these releases began at 8:50 a.m. and ended at 10:50 a.m. on December 7, spewing 0.64 tons of methane into the atmosphere. This release overlapped with an observation from NASA’s Landsat 9 satellite.

The IMEO, which is supported by the European Commission, said that the release was also detected by the European Space Agency's Sentinel-3 SLSTR satellite at 9:48 a.m. and again at 10:27 a.m. as well as the agency's Sentinel-5P satellite.

Tallgrass Energy has reported deliberate emissions to Wyoming regulators for pipelines associated with their Douglas Gas Plant.

Tallgrass Energy Partners, LP said in its Dec. 8 email to regulators that it hadn’t yet conclusively determined the source of the high oxygen levels but believed they were caused after a pipeline project “inadvertently” wasn’t completely purged of residual oxygen.

Tallgrass Energy said in a statement that it is committed to operating in full compliance with regulatory requirements. "We provided a report to the state, and should we find that our reporting needs to be amended, we will take the appropriate action," the company said. "A paramount focus for Tallgrass is the safe and reliable operations of our facilities."

According to Steven Hamburg, chair of the scientific oversight committee at the IMEO and chief scientist at the Environmental Defense Fund, many intentional emissions from energy operations can be avoided through more rigorous maintenance. Hamburg noted that while in some rare cases deliberate releases may be necessary to avoid a potential explosion, many emissions can be avoided altogether. The Environmental Defense Fund is expected to launch its own methane-detecting satellite later this year.

In 2020, a consortium including Blackstone Inc and GIC Pte., Singapore's sovereign wealth fund, bought the pipeline company, which has oil and gas conduits across the US. Blackstone referred questions to the operator. GIC declined to comment.

An official with the US Pipeline and Hazardous Materials Safety Administration (PHMSA) said that while pipeline operators are required to disclose natural gas releases that meet certain criteria, the agency did not find any National Response Center notifications during December for the area in question. The agency is currently working on a rulemaking to establish additional protocols aimed at reducing leaks from all regulated pipelines.