The Oklahoma Corporation Commission confirmed that an "uncontrolled gas release" caused the Jan. 22 explosion that killed five men on a gas rig in Oklahoma.
The explosion and fire obliterated the rig at the Pryor Trust 1H-9 well in Pittsburg County, Okla., which was operated by Patterson-UTI Energy Inc. for Red Mountain Energy.
"Patterson rig 219 was on fire from uncontrolled gas release. Employee attempted to close blind rams and shut off well," the commission said, adding that it took specialists from Boots and Coots to shut in the well by approximately 4 p.m. the same day. Efforts to shut the well included the use of heavy drilling mud and three different cement plugs at depths from more than 7,000 feet to 2,145 feet.
An investigation into the well explosion by The U.S. Occupational Safety and Health Administration, or OSHA, prevented the well from being moved from the blast site until Feb. 14. The Oklahoma commission's investigation report cited Patterson-UTI and Red Mountain for general pollution violations related to the explosion, while the OSHA investigation remains ongoing.
Red Mountain did not immediately respond to a request for comment. Patterson-UTI has maintained a link on its website expressing sympathy for the families of the five men killed in the blast and saying "we are actively investigating the cause of the tragedy so we can learn from it and protect against it happening again."
The well explosion could have legal ramifications for Patterson-UTI and Red Mountain. According to The Associated Press, two wrongful-death suits have been filed in Oklahoma's Pittsburg County Court against the companies by survivors of two of the workers who were killed in the blast.
