Williams has identified the worker killed at the company's southwest Wyoming plant Wednesday as 36-year-old Michael Smuin of Kemmerer. The company says he was an operations technician at the Opal natural gas processing plant and had been with the company eight years.

The circumstances surrounding Smuin's death are still unclear. On Thursday, the Wyoming Occupational Safety and Health Administration said a burst pipe may have been involved. A spokeswoman for the agency says a worker on-scene also reported seeing a cloud of natural gas.

The plant was taken offline after the incident, but Williams has since restarted it.

A major explosion at Williams' Opal plant in 2014 forced the evacuation of the town, but no one was injured.