Methane Plume Seen by Satellite Over Alabama Mystifies Experts

Methane Plume Seen by Satellite Over Alabama Mystifies Experts

A large methane plume was spotted over northwestern Alabama near natural gas and coal sites three weeks ago -- though regulators have been unable to identify what spewed out the harmful greenhouse gas.

The Oct. 22 release was detected by satellite and pinpointed to an area in Marion County near natural gas wells in the Black Warrior Basin, a pair of gas pipelines and coal mines, some dating back to the late 1800s. An emissions rate of about 58 tons of methane per hour would have been required to generate the plume, according to an estimate from Kayrros SAS, which analyzed European Space Agency data. 

The Alabama release is the fifth largest detected by the ESA’s Sentinel-5P satellite this year in the lower 48 U.S. states, according to Kayrros. State and federal regulators couldn’t identify the source with the satellite data, underscoring how difficult it is to use this greater visibility from space to take the next steps to understand the cause or to hold companies accountable.

Methane is the second-largest contributor to global warming after carbon dioxide, and halting intentional releases and accidental leaks could do more to slow climate change than almost any other measure. Methane is the primary component of natural gas, and leaks can occur anywhere along the natural gas supply chain from the wellhead to homes and businesses where the fuel is burned, and the greenhouse gas can also be released during oil and coal production.

Methane Plume Seen by Satellite Over Alabama Mystifies Experts

The Alabama Department of Environmental Management wasn’t able to identify a permanent facility that would be responsible for any releases after a diligent review of its records, spokeswoman Lynn Battle said in an email. The agency wasn’t able to research or identify transient releases, she said.

Kinder Morgan Inc. said the release wasn’t caused by its two conduits traversing the area, Tennessee Gas Pipeline and Southern Natural Gas. While coal mines can also release methane, operations in the area have scaled back.

“There is no active mining in the area,” Dustin Morin, director of the mining and reclamation division of the Alabama Department of Labor, said in an emailed statement. He said the source was more likely associated with an old gas well and rather than an old reclaimed surface mine. 

The U.S. Environmental Protection Agency said that the potential area is too broad and the satellite data “does not provide enough tangible information of potential sources in which to conduct a programmatic review,” a spokesman from the Region 4 office in Atlanta said via email. 

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