On Tuesday, Oklahoma’s government acknowledged that earthquakes throughout the state have mostly been caused by wastewater-injection wells, which are often used to dispose of fracking waste products. The New York Times reports that previously, the state government has hesitated to embrace the association between drilling and seismic activity. Now, a new website introduced by the state’s energy and environment cabinet details evidence showing that drilling has contributed to the rising number of earthquakes in the state. In addition to providing links to expert studies, the website features an interactive map showing the location of active wastewater-injection wells and earthquake sites.
NYT reports that the state-run Oklahoma Geological Survey released a statement that “considers it very likely” that most of the earthquakes in the state are caused by wastewater wells; the website agrees with this statement. The statement also pointed out that seismic activity “is occurring over a large area, about 15 percent of the area of Oklahoma, that has experienced significant increase in wastewater disposal volumes over the last several years.”
In recent years, Oklahoma has seen a sharp increase in earthquakes. Previously, there were only about one and a half earthquakes with magnitude greater than 3.0 in an average year. NYT reports that this number skyrocketed once oil and gas drilling became widespread in the mid-2000s. Last year, there were 585 earthquakes of 3.0 or greater, this is more than any state expect for Alaska. This year, the state is expected to see over 900 quakes. Although most of the seismic activity has not been catastrophic, residents who live in vulnerable areas are worried that that the cumulative effect will ultimately damage their property and impact their quality of life. There have been more severe quakes as well. In 2011, a series of shocks exceeding 5.0 caused millions of dollars in damage. According to NYT, some experts caution that there may be larger and more serious quakes if the state does not take further action.
Up until now, the government has downplayed the relationship between drilling activity and earthquakes. Gov. Mary Fallin, a Republican, was skeptical of the relation last fall and said that more research was needed. On Tuesday, she acknowledged that the Geological Survey’s statement was significant and stated, “Oklahoma state agencies already are taking action to address this issue and protect homeowners,” according to NYT.