Massey Energy, owner of the Upper Big Branch mine where the explosion occurred April 5, said a 16-member group was to enter the mine Wednesday, CNN reported.
"We are eager to begin a thorough investigation into the root cause of the accident," Massey Energy Chairman and Chief Executive Officer Don Blankenship said.
Massey shares have fallen about 40 percent since the explosion. The company also faces the possibility of a criminal investigation.
Federal records indicate the mine has a checkered safety record, with three other deaths in the past 12 years.
Notable deaths of 2014 [PHOTOS]