Six earthquakes of magnitude-3.5 or greater have occurred in the west Texas area since February 2020
The Railroad Commission of Texas (RRC), which oversees the state’s oil and gas industry, issued a notice last week on saltwater disposal wells, where fracking wastewater is injected underground. The order is in place until further notice in the Midland Basin area.
Since February 2020, six earthquakes of magnitude-3.5 or greater have occurred in the west Texas area. These included a M-3.7 earthquake in Martin County on 7 setembro 2021, and two M-3.6 earthquakes northeast of Odessa in February 2020 and May 2021, the commission noted.
The RRC said that its analysis found that wastewater injection wells for fracking “likely contributes to seismic activity”.
Along with no new permits, 76 wells were asked to reduce their maximum daily injection rate to 10,000 barrels.
Wells that have permits, but are not already in use, received a request to hold off injecting fluids. The RRC said it expected the orders to last at least a year.
Em uma declaração para O Independente RRC spokesperson, Andrew Keese, disse: “The Railroad Commission of Texas’ most critical mission is protection of public safety and the environment.
“The RRC’s Seismologist and staff have been investigating recent earthquakes close to populated areas near Midland and Odessa, and assessed steps that could be taken by oil and gas operators to help mitigate the events.”
He added that the RRC has made similar requests in other areas in the past for voluntary permit changes to address seismicity.
Fracking – hydraulic fracturing, officially – is the process of recovering gas and oil from shale rock. Well operators drill vertically, or horizontally at most new US sites, then force a highly-pressurised mix of sand, water and chemicals against a rock formation. The large volume of liquid breaks apart, or fractures, the rock layers to release deposits of gas and oil.
West Texas’s Permian Basin is America’s most productive oil patch and has seen a fracking boom in the past decade. But the practice has raised a number of environmental and health concerns, including the increased likelihood of so-called “frackquakes”.
When the large quantities of water are blasted underground, it increases the risk of hitting fault lines or exacerbating movement along tectonic plates.
Fracking operations that drill deeper into the earth can make triggering an earthquake almost 10 times more likely, de acordo com um 2020 estude. O relatório, publicado no Bulletin of the Seismological Society of America (BSSA), was based on data from more than 1,300 single well sites across Oklahoma.
The study found that in one rock layer, the likelihood that fracking triggered seismic activity increased from 5 para 50 per cent with increasingly deeper well operations, a partir de 0.9 para 3.4 milhas (1.5 to 5.5km).
And while some fracking water is recycled, the drilling method still requires millions of gallons, a particular issue in Texas where the climate crisis is driving more extreme heat and drought conditions.
UMA 2015 study found that in the Permian Basin, fracking uses between 264,000 e 2.6 million gallons of water each time, Scientific American relatado. There is also a risk that groundwater can be contaminated from chemicals used in the injection solutions.
Methane, the primary component of natural gas, é 25 times more effective at trapping heat in the atmosphere than carbon dioxide. UMA 2015 estude made the conservative estimate that the Barnett Shale region in Texas leaked 544,000 tons of methane annually – equivalent to 46 million tons of CO2.
Seth Gladstone, of the NGO Food & Water Watch which has called for a ban on fracking, contado O Independente last year that the fracking carried “numerous inherent risks”.
“But among the most immediate and potentially disastrous of these risks are earthquakes. No one wants earthquakes under their feet or under their homes. And no one who has come face to face with any of the devastating effects of fracking would choose to live in proximity to them," ele disse.
This article has been updated to include the RRC spokesperson’s comment