Additional inspectors were sent to Gardendale seismic response area north of Odessa last week by Railroad Commission of Texas after two earthquakes Oct. 26 of magnitude 3.4 and 3.6. They are inspecting saltwater disposal well sites. As a result of previous earthquakes, the agency in September had requested 25 operators of 76 wells in Gardendale to provide injection data and reduce daily injection volumes of produced water. Agency staff determined that saltwater disposal well injection “likely contributes to seismic activity in the Gardendale SRA.” The procedures are expected to be in effect for at least a year. Odessa American said among the companies that indicated they will comply were Fasken Oil and Ranch, Rattler Midstream, COG Operating, Occidental Permian, Pioneer Natural Resources and Wasser Operating.
Last week the commission also established the northern Culberson-Reeves SRA to address the frequency of earthquakes there. The agency submitted a list of disposal wells in the area, including those operated by BPX Midstream and Chevron, according to Midland Reporter Telegram, with proposed volumes that would reduce permitted volumes from 10 percent to as much as two-thirds.
After the Oct. 26 earthquakes, officials at Texas A&M said Texans “should not be overly alarmed because the state lies in a relatively safe zone.” Fred Chester of A&M’s College of Geosciences added, “Earthquakes can happen just about anywhere in North America, but the risk varies greatly… The risk in Texas is lower overall than most other places in the U.S… The largest and most devasting earthquakes … occur at tectonic plate boundaries, and Texas is far from plate boundaries.” He said fluids in the earth’s crust play a role in earthquakes. “Pumping fluids in and out of the crust can locally trigger earthquakes that would eventually occur naturally… Triggering is most likely to occur when pumping particularly large volumes of fluids quickly.”