A magnitude 5 earthquake struck Oklahoma on Sunday near the largest U.S. oil storage hub, prompting some pipeline companies to shut down operations at the site as a precaution.
The tremor occurred 2 kilometers (1.24 miles) west of Cushing at a depth of 5 kilometers, followed by a smaller quake in the area less than an hour later, according to the U.S. Geological Survey’s website.
Magellan Midstream Partners LP, a pipeline operator, is working through a controlled shutdown of its assets in the area, spokesman Bruce Heine said in an e-mailed statement. There was no damage to its assets and it expects to resume operations on Monday, he said. Enbridge Inc. spokesman Michael Barnes said by e-mail that there was no impact on the company’s facility in Cushing.
Other major storage and pipeline giants like Houston-based Enterprise Products Partners, Kinder Morgan and Phillips 66 said their operations weren’t impacted.
All companies that run intra-state pipelines that fall under the jurisdiction of the Oklahoma Corporation Commission have shut down operations as a precaution, Matt Skinner, a public information officer for the OCC, said by phone. Magellan typically discontinues operations to check the integrity of assets if an earthquake over a certain strength occurs, Heine said. Kinder Morgan Inc., another pipe operator, isn’t aware of any impact on its Cushing operations, Richard Wheatley, a Houston-based spokesman for the company, said in an e-mailed statement.
The OCC’s Pipeline Safety Department has been in contact with pipe operators at the storage terminal, and there have been no immediate reports of problems, the OCC said in an earlier advisory on its website.
Cushing, about 70 miles northeast of Oklahoma City, is the delivery point for West Texas Intermediate crude, the U.S. benchmark oil. WTI futures were up 1.7 percent at $44.82 a barrel on the New York Mercantile Exchange at noon London time.
Electricity has been restored to almost all of Cushing, Jeremy Frazier, assistant city manager, told reporters at a televised press conference. Authorities have been in contact with tank farms in the area and there has been no damage to terminals, he said. While some gas leaks occurred, they have been contained and are no longer a threat, according to Frazier. There was some structural damage to buildings in the city’s downtown area, he said.
Several producers, as well as the U.S. Environmental Protection Agency, are facing lawsuits because of seismic activity allegedly linked to oilfield wastewater disposal in Oklahoma and other states. The OCC, which regulates oil and gas activity in the state, has been issuing restrictions for more than a year aimed at cutting down on the amount of wastewater injected into underground wells.
There are about 35,000 active wastewater disposal wells, though only a few dozen have been linked to quakes, according to a Bloomberg Intelligence report in May, citing the USGS. A 5.6 magnitude tremor had struck Oklahoma in September, which tied a state record set in 2011.Following earthquake at Cushing on Sunday, minor tremors occurred at Nicoma Park, east of Oklahoma City, and Fairview, in the western part of the state.
The region, previously not known for intense seismic activity, began having a significant number of earthquakes in 2009, the same year area oil companies began using fracking to shatter deep rock layers to extract oil and gas. Fracked wells produce large quantities of wastewater, which drilling companies inject into ultra-deep disposal wells.