While Oklahoma has attracted most of the interest nationally regarding connections between earthquakes and wastewater injection wells, experts in Pennsylvania claim to have found a similar connection.
The Pennsylvania Department of Environmental Protection contends the hydraulic fracturing operations have caused low-level earthquakes in the state. The minor earthquakes occurred last April in Lawrence county near the Ohio border. They measured 1.8 to 2.3 magnitude and were not felt by humans and caused no known damage.
The DEP reported all of the quakes happened in an area less than one mile from a natural gas well owned by Houston-based Hilcorp Energy Co. Hilcorp operates four wells within a 5-mile radius of the epicenter of the minor earthquakes.
Just as Oklahoma’s Corporation Commission issued orders reducing the operation of wastewater injection wells, Pennsylvania’s Department of Environmental Protection issued recommendations last fall. One was to call for an end to the practice known as zipper fracturing of wells that are separated by less than a quarter mile. The State also recommended seismic monitoring and a mitigation plan for Hilcorp.
If a quake of 1.0 magnitude or greater happens within 6 miles of any active Hilcorp well, the company has to notify the DEP and suspend operations on the well.