State regulators need to pay more attention to human activities, such as oil and natural gas development, that have the potential to cause earthquakes, according to a 150-page report released Monday by the StatesFirst Initiative.
The report rejects a “one-size-fits-all” approach, urging regulation to fit individual state laws and geography.
Induced seismicity is site-specific and always technically complex, so there are no easy preventive measures, according to the report.
In response, the Environmental Defense Fund (EDF) said the report confirmed the link between wastewater injection by oil/gas operators and seismic activity. "The report recognizes injection can be a contributing factor and provides objective, helpful advice on what can be done about this problem," said EDF's Scott Anderson, senior policy director for U.S. climate and energy.
In recommending that states have well thought out communications plans to deal with the issue when it occurs, StatesFirst said states should be ready to use "tools, knowledge and expertise" from the report and its appendices to both prepare and respond.
StatesFirst partnered with the Interstate Oil and Gas Compact Commission and the Ground Water Protection Council to compile the most current science on the issue of oil/gas hydraulic fracturing (fracking) and wastewater deep injection wells. Thirteen states participated, many of which have not experienced induced quakes, but the report urges them to develop regulations and procedures nevertheless.
Four states that have experienced apparently oil/gas-related seismic activity -- Oklahoma, Texas, Colorado and Ohio -- were all represented, and Rick Simmers, chief of the Ohio Department of Natural Resources’ Oil and Gas Resources Division, co-chaired the report committee. Simmers said the report is designed to be a primer for the participating states, giving them "up-to-date scientific and technical data, case studies and several suggested approaches for detecting and managing the quakes."
StatesFirst is a collaborative effort including the governors, regulators and policy leaders from participating oil/gas producing states, which also include Alaska, Arkansas, California, Illinois, Indiana, Kansas, Utah, West Virginia and Wyoming.
Oklahoma in particular has experienced a steady increase in seismic activity in the past five years, and its state regulators in August ordered a 60-day period during which wastewater injection volumes will be reduced 38%, or about 3.4 million barrels under the 2014 total (see Shale Daily, Aug. 4). Some designated drilling areas have seen a sharp rise in seismicity since late 2012.
Induced seismicity related to underground injection activity has been observed for more than 50 years, dating back to the Rocky Mountain Arsenal near Denver, but the steep increase in quake activity in the Midcontinent since 2009 has focused renewed attention on the phenomenon. "The science required to understand the process and predict its impacts is still undergoing significant change," the StatesFirst report said.
The report focuses on induced seismicity associated primarily with underground disposal oilfield-produced fluids in what are labeled as Class II wells, although there is brief discussion of the possible link with fracking, which is "far less likely to occur," according to the report.
"The majority of disposal wells in the United States do not pose a hazard for induced seismicity, but under some geologic and reservoir conditions, a limited number of injection wells have been determined to be responsible for induced earthquakes.” The authors also said it is "very difficult" to clearly differentiate between induced and naturally occurring quakes.
The report lists seven basic questions that could correlate oil/gas activity to quakes, noting that if all seven are answered negatively, the observed seismic activity could not be tied to induced injection. There is also a recommendation for five areas needing future causation studies, such as deploying temporary seismic monitoring networks and reviewing all available seismological archives and records for a given area.
"Because of the site-specific considerations and technical complexity of tailoring a risk management and mitigation strategy, many state regulators choose to work with experts from other government agencies, the regulated community, universities, and private consultants," the report said.