Report on deadly oil rig explosion to find company culpable

Oklahoma-based news service Tulsa World has reported that on 12 July the US Chemical Hazard and Safety Board will release its full investigation into an oil well blowout that killed five workers on 22 January 2018.

The explosion at the onshore drilling site near the town of Quinton — 160 km south of Tulsa, and operated by Oklahoma City-based Red Mountain Energy — was the result of a range of operational and safety management problems, according to the investigators. The report will show key findings:

• The alarm system was off.
• Systems to prevent gas entering the well and a blowout were poorly managed.
• Gas influx indicators either elicited an inadequate response or went unrecognised.
   

A Chemical Safety Board investigation update in August noted that “strong indications” of a hazardous influx of gas existed at least a half hour before the explosion. And an indicator of conditions conducive to a blowout showed a level 10 to 20 times greater than general industry standards that would trigger alarms, the agency’s lead investigator stated.

The remains of the five workers who died were found in a room where drilling operations take place on the derrick. A sixth worker was injured while trying to close the blowout preventer before escaping by sliding down a guy-wire.

Other highlights of the Chemical Safety Board’s overview of its final findings include:

• Operations were under-balanced — meaning the drilling fluid or “mud” wasn’t dense enough to keep gas out of the wellbore — and were performed without proper planning, procedures or needed equipment.
• The blowout preventer couldn’t close because its hydraulic hoses were burned.
• Flow checks — when operations are halted to see whether mud is flowing out of the well at the surface to indicate a possible influx of gas — weren’t conducted.
• The design of driller cabin design where the five men died was flawed.
• Gaps were present in the safety management system.
• There were a lack of safety requirements stipulated by regulations.
   

Industry standards exist, but a Chemical Safety Board report from 2014 noted that “serious incidents continue to occur”, suggestive that the industry’s “voluntary guidance is insufficient”.

The flawed cabin design finding may be related to an Occupational Safety and Health Administration determination that an emergency descent device had gone uninspected and was inoperable. A lawsuit also claims that the cabin — or “doghouse” — configuration would have forced each man to be exposed to the inferno and exit one at a time.

Image: Inspectors and emergency crews surveying damage at Patterson-UTI's rig 219, which exploded and caught fire 22 Jan 2018. Source: Oklahoma Corporation Commission.