LEAVITTSBURG, Ohio - The Ohio Department of Natural Resources says it's keeping a closer eye on oil and gas drilling throughout the state.

The series of earthquakes recorded in March in Poland Township, prompted new oversight into what's happening beneath the surface at horizontal drilling sites.

ODNR traveled to a monitoring site near a Leavittsburg injection well on Tuesday for the installation of a sensitive seismic monitor. ODNR says the state has installed more than 20 of these monitors across the state. The devices are usually installed in groups of about five in a radius surrounding a well site.

"By having multiple stations, we can triangulate on the event and determine where it's at, how deep it is," Michael Hastings says, owner of Hastings Microseismic Consulting. 

Hastings was hired by ODNR to install the monitors at injection well sites. The state is paying $22,000 per monitor. 

The state acknowledged a probable link between fracking and the seismic activity in Poland this spring. The horizontal well that sits on the suspected Hilcorp pad remains inactive until required monitors are installed. The requirement is part of ODNR's tougher permitting conditions for drilling activities near faults and areas of seismic activity.

New ODNR permits issued for horizontal drilling within 3 miles within known sensitive areas or areas of seismic activity greater than a 2.0 tremor, require companies to install sensitive seismic monitors.

ODNR Spokesperson Mark Bruce says the state does not have the resources to map out trigger spots in advance, only during the drilling and fracking process. 

And there's NO guarantees another round of quakes won't strike Mahoning County again if another horizontal well is drilled or fracked in areas that have not been explored.

"No earthquake can be prevented anywhere, you can not prevent an earthquake, it's just that simple," Bruce says.

The only way to know is by trial and error and Bruce says the state is doing what it can to arm itself with information from devices planted underground.

"You're never going to be able to prevent it, what we can try to do is identify the possible risks that are out there and do what we can to minimize those risks," Bruce says.

If tremors are recorded, data from the sensitive seismic monitors will be sent to ODNR officials at their headquarters in Columbus.

"We even have it set up so that if any of our equipment anywhere registers a seismic event of a certain size, an email gets pinged out right away and everybody knows," Bruce says.

Bruce says Ohio is the leader among other states including Texas and Oklahoma when it comes to identifying possible risks with sensitive seismic monitors.

A horizontal drilling moratorium remains in effect within the 3 mile radius of where the Poland earthquakes were recorded this year. Bruce says Hilcorp has indicated it would like to put its other wells back into production at some point. It's not yet known if and when the fracking moratorium will ever be lifted for further shale exploration.