A worker was killed on Monday evening when a small drilling rig he was operating rolled over and crushed him at a site in West Virginia.
The man, whose name was not disclosed, was working for Louisiana-based services outfit Omni Energy, which was contracted by Houston-based Seitel to drill holes for the purposes of seismic testing.
Omni spokesman Mark Stipe confirmed the death in an email and said the company is "co-operating fully with government officials" in an ongoing investigation.
"We mourn the loss of our employee and our thoughts and prayers are with the family," Stipe said.
The incident occurred in Fairview, Marion County, near the Loveridge Preparation Plant, operated by Consol Energy.
Consol said it had been notified of the accident at around 18:10 local time on Monday. The company, which produces coal and natural gas, said it had granted Seitel access to its property to conduct geophysical seismic testing in the vicinity of the Loveridge facility.
"The independent testing was not associated with Consol Energy’s active coal mining or gas operations," Consol said, adding that Seitel had obtained the necessary permits for the exploration work.
The federal Mine Safety & Health Administration (MSHA) said the rig was drilling 30-foot holes and setting off shots to do seismic work in the Marcellus shale formation.
MSHA said it handed over the investigation to the Occupational Safety & Health Administration as the accident did not occur on bonded mining land.
Seitel, a seismic specialist, declined to comment and referred all questions to Omni.