Ohio has experienced a total of 11 earthquakes in the last year, the most recent on Dec. 31 coming in at a 4.0 on the Richter scale. Drilling operations using the fracking process to try to extract natural gas from underground shale have been injecting thousands of gallons of wastewater into the ground near a fault line, and now some Ohio officials have said that this could be the cause of the Earthquakes.

Though federal regulations have deemed fracking safe, many environmentalists and property owners aren't so sure. And though Ohio Department of Natural Resources Director Jim Zehringer said in a teleconference that fracking is not the cause of the earthquakes, all fracking in the Youngstown area has been suspended while further research is conducted.

The most recent earthquake was the strongest of the eleven, which, on average, were around 2.7. This is the biggest one we've had so far, Patti Gorcheff said to USA Today. Gorcheff is a Ohio resident who has raised concerns about quakes and drilling-related activity in the region. I hope this is a wake-up call, she said.

Charles Kihm, who lives a few miles from the epicenter, told USA Today the quake made so much noise that he thought a vehicle had hit his house. It really shook, and it rumbled, like there was a sound, said Kihm. It was loud. It didn't last long. But it really scared me.

The Ohio Seismic Network said that more quakes are possible, and would be until all of the pressure on the fault is relieved.  

There are a total of 177 fracking operations in Ohio, though Youngstown is the only one that has experienced seismic activity.  Zehringer said that all other operations would remain open, and that to shut them down would be an overreaction.