The blowout in rural Ohio took place Feb. 15, 2018, at a well owned by XTO Energy, a subsidiary of ExxonMobil, and it took 20 days to get it under control. The well had been “fracked,” or hydraulically fractured, before the blowout took place. Workers had been completing the well, according to news reports at the time, a job made more difficult by heavy rains and a crane that collapsed when the explosion took place.
“We deeply regret this incident occurred and are committed to identifying and managing risks associated with our activities to prevent recurrence,” Julie L. King, a spokeswoman for ExxonMobil, said in an email.
The new report gauges that the mishap spewed 60 kilotons of methane into the atmosphere — five times the amount ExxonMobil estimated.
“We are eager to learn more about their study,” King said. “ExxonMobil is working with government laboratories, universities, NGOs and other industry participants to identify the most cost-effective and best-performing technology, including satellites, that can be adopted by all producers to detect, repair and accurately measure methane.”
It is the first time methane from an oil or gas incident has been both detected and quantified via satellite during a routine global survey.
Steven Hamburg, chief scientist at the Environmental Defense Fund and a co-author of the report, noted the unique aspect of the data gathering. “Methane emissions are a huge contributor to climate change, he said. “But source locations are often unpredictable and can occur in out-of-the-way places all over the globe. New results show the opportunity for satellites to help see and quantify emissions no matter where they are.”
EDF, which will launch its own satellite in 2022, estimates that emissions from the oil and gas sector are 60 percent higher than estimates by the Environmental Protection Agency.
The accident highlighted the expanded use of natural gas in the United States, thanks to the sharp increase in fracking and to opposition to coal-fired power. Natural gas emits only half the greenhouse gas as coal at the point of combustion.
But leaks of methane throughout the production system can undercut the advantage of natural gas and can drive emissions back up to dangerous levels.
Methane is a powerful greenhouse gas, up to 25 times as potent, pound for pound, as carbon dioxide, according to EPA estimates.
Major oil companies have said that they are improving their ability to capture methane and seal leaks, yet many environmental groups say difficult-to-detect leaks — from the wellhead to the processing plant to the distribution pipes — continue to offset the advantages of natural gas.
The blowout in Ohio was measured by the Tropospheric Monitoring Instrument, a satellite that at the time was doing a routine global survey of methane emissions, scientists said in an article published in the Proceedings of the National Academy of Sciences.
The satellite was able to observe the well on the 13th day of the blowout, and it calculated the changes in well pressure and the speed of emissions.
“To combat climate change and build a low-carbon economy, being able to accurately monitor greenhouse gas emissions is an essential prerequisite,” the study said. Its authors said that the study shows how methane emissions “from large gas leakages due to accidents in the oil and gas sector can escape the greenhouse gas emission accounting system, adding a significant source of uncertainty to the annual estimates reported to the United Nations Framework Convention on Climate Change.”
“Satellite-based instruments that regularly scan the entire globe provide a means to detect and quantify methane emissions, which are challenging to measure,” said the article, whose lead author was Sudhanshu Pandey of the SRON Netherlands Institute for Space Research.
The group said its paper “highlights the importance of accidental emissions for regional and national-scale emission reporting and inventories, as the lack of incorporating such emissions can lead to significant underestimation of overall emissions.”
Since the blowout, dozens of permits have been issued for oil and gas facilities in Belmont County where the well was located, according to the nonprofit group Earthworks.
“This study validates what Earthworks has seen and been saying for years, that oil and gas methane pollution is higher than regulators and operators are reporting to the public,” said Leann Leiter, Earthworks’ Pennsylvania and Ohio field advocate. “The solution is for stronger standards that put the responsibility on companies to prove actual decreases in emissions and, ultimately, to stop issuing new production and infrastructure permits that result in increasing pollution, and to instead protect both people and the climate.”