Natural gas extraction and related activities, including hydraulic fracturing and the underground injection of wastewater, can cause earthquakes. We know this to be true. The occurrence of so-called induced seismicity or man-made earthquakes is a documented phenomenon around the globe, including in the United States, Canada and Great Britain.
If North Carolina proceeds in opening the state to the oil and gas industry, the issue of induced seismicity must be further scrutinized.
The North Carolina Mining and Energy Commission and state lawmakers in Raleigh have slapped together 120 rules in just 18 months to throw wide open the door to fracking in our state. In their rush to give the oil and gas industry everything it wants, our public servants have not adequately addressed the issue of induced seismicity. It would be prudent for North Carolina legislators to re-examine this issue immediately at their Joint Legislative Commission on Energy Policy meeting Thursday and begin a new public comment process.
Specifically, we know that injecting fracking wastewater can cause earthquakes. North Carolina currently has a ban on injection wells for the disposal of industry waste, but it may be just a matter of time before the industry applies pressure to lift this ban, once drilling is in full swing. About 90 percent of oil and gas water waste is disposed of with injection wells so its hard to imagine that the industry doesnt envision this for North Carolina.
We also know that hydraulic fracturing itself has caused earthquakes, although there have been fewer documented incidents. We need more research to understand the relationship between fracking and earthquakes and to develop strategies to prevent these quakes.
A series of earthquakes up to magnitude 3.0 recently struck Mahoning County, Ohio. On April 11, the Ohio Department of Natural Resources announced that the earthquakes were likely caused by hydraulic fracturing and that the state would begin requiring drillers to monitor for seismic activity during hydraulic fracturing and shut down operations if earthquakes occur. Ohio is the first U.S. state to propose such requirements.
In Canada, the British Columbia Oil and Gas Commission issued a report documenting a series of 38 earthquakes in the Horn River Basin up to magnitude 3.8 in northeast British Columbia between 2009 and 2011. The Canadian government concluded that these earthquakes were caused by hydraulic fracturing.
BCOGC researchers made a series of recommendations in 2013, including:
• Improving geologic and seismic site characterization to identify and avoid pre-existing faults.
• Developing procedures for induced seismicity monitoring and reporting.
• Developing requirements for operators to submit microseismic data collected during hydraulic fracturing.
North Carolina must adopt similar preventative regulations for every drilling company entering the state.
Man-made earthquakes from oil and gas production have been happening in Arkansas, Colorado, Ohio, Oklahoma and Texas where natural earthquakes are infrequent, meaning that these communities are unprepared to deal with the effects. North Carolina is in the same situation. Chatham, Moore and Wake counties are dotted with towns and cities, utilities and infrastructure. Residential and commercial buildings have not been designed or built with the anticipation of earthquakes.
The risk of quakes from oil and gas activity is real. Man-made earthquakes can be big enough to cause property damage or injuries, and smaller quakes that dont cause damage can still be a nuisance and source of anxiety for communities near fracking. It is imperative that lawmakers slow down the rule-making process to fully address the seismicity issue. The rush to bring fracking wells into North Carolina has been ill-conceived from the start. This complex process is not a race.
Briana Mordick, who received a masters in geology from UNC-Chapel Hill, is a staff scientist with Natural Resources Defense Council.