Geologist Link Earthquakes With Hydraulic Fracturing

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State regulators have announced new rules for fracking near known faults and areas of past seismic activity in wake of a series of earthquakes in Mahoning County about a month ago. 

Drilling within 3 miles of “a known fault or area of seismic activity greater than a 2.0 magnitude” will have to be monitored with “sensitive seismic monitors” by companies, according to Ohio Department of Natural Resources. 

The agency said in a release that the new policy is in response to recent earthquakes in Poland Township “that show a probable connection to hydraulic-fracturing near a previously unknown micro-fault.” 

“While we can never be 100 percent sure that drilling activities are connected to a seismic event, caution dictates that we take these new steps to protect human health, safety and the environment,” ODNR Director James Zehringer said in the release. 

At least 12 earthquakes occurred in early March near an active fracking operation, prompting Natural Resources to shut down the process. Initially, the state said there was no evidence linking fracking and the temblors. 

The largest registered at magnitude-3.0. 

“ODNR geologists believe the sand and water injected into the well during the hydraulic fracturing process may have increased pressure on an unknown micro-fault in the area,” according to the release. 

The link is one of the first in the U.S. between fracking and earthquakes; injection wells have been linked to quakes for some time. 

To pull oil and natural gas from shale, companies drill vertically, then turn 90 degrees into the rock. Then they blast millions of gallons of water, sand and chemicals into the shafts to free trapped oil and gas. 

A series of earthquakes in Mahoning County in 2011 was tied to a fracking-waste-injection well near Youngstown. That well was shut down by the state. 

During the fracking process, fluids bubble back up with the gas. Oil and gas wells also produce saltwater contaminated with metals and radioactive materials trapped underground for millions of years. That waste often s injected into deep wells. 

At the time of the first Youngstown earthquakes, there were 177 active waste-injection wells. Now, there are more than 188, and more are being drilled in eastern Ohio. 

But none is near the most-recent earthquakes, which is why geologists suspect the fracking operations.

Will Drabold is a fellow in the E.W. Scripps School of Journalism Statehouse News Bureau.  

State geologists in Ohio have for the first time linked earthquake activity in the Marcellus Shale basin to hydraulic fracturing, confirming the suspicions of activists pushing for drilling limits in the interest of public health.

State Oil & Gas Chief Rick Simmers told The Associated Press on Friday that a state investigation of five small tremors in the Youngstown area last month has found a probable link.

He said Ohio is setting new permitting conditions in earthquake-sensitive areas and has halted drilling indefinitely at the site of the March quakes.

A seismologist with the U.S. Department of Interior said it's the first time seismic activity has been linked to Marcellus shale exploration that's swept the northeastern United States over the past several years.