Texas Railroad Commission probing Midland-area earthquake for connection to fracking

The Railroad Commission of Texas, the governmental agency tasked with overseeing oil and gas production in the state, is investigating the 5.1-magnitude earthquake that rattled much of West Texas Monday night for any connection to produced water disposal wells related to petroleum extraction.

The Railroad Commission said in a statement to the Avalanche-Journal Wednesday the agency is looking into the more than 50 earthquakes that have stricken Martin and surrounding counties since Monday, including a magnitude 5.1 quake originating 28 miles north of Midland that shook cities and towns across the western part of the state — one of the strongest in Texas history.

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"The RRC has been in contact with operators and sent inspectors to the area as part of our efforts to reduce seismicity possibly caused by underground injection of produced water into disposal wells," the agency wrote. "The RRC will then evaluate next steps that could potentially be taken to mitigate earthquakes to protect residents."

Produced water is fluid that comes out of the ground usually as a byproduct of fracking, or hydraulic fracturing. The water is injected into the ground at high pressure to fracture rock and release oil reserves, then comes back up with the petroleum. It is then usually pumped back deep underground for disposal in a process that is believed to be linked to more frequent, more intense earthquakes in West Texas.

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The Railroad Commission also investigated following a spate of quakes in Scurry and Fisher counties in late July, leading them to shut down two produced water disposal wells in the area.

That series of more than 60 earthquakes in one week — including three measured at a magnitude greater than 4.0 and one magnitude 5.1 tremor — prompted the Scurry County judge to issue a disaster declaration while the commission investigated.

This article originally appeared on Lubbock Avalanche-Journal: Railroad Commission probing cause of West Texas earthquake