The report on the April 2010 blast that killed 29 workers will be made public during a briefing to be held at the National Mine Health and Safety Academy in Beaver, West Virginia, at 3pm local time.

An agency spokesperson did not respond to an ILN request for specific details about the report by press time.

The MSHA investigation is one of several that commenced after the April 5, 2010 explosion at the Raleigh County, West Virginia operation. An independent probe has already been completed, along with an internal report by then-owner Massey Energy.

Industry union the United Mine Workers of America also recently released its report.

Both the independent review and the UMWA probe cited a build up of coal dust caused by improper and inadequate rock dusting as a trigger for the blast. Massey's own report pointed to an inundation of naturally-produced ethane.

MSHA released preliminary findings to victims’ families and the public in late June. It blamed Massey for the accident in that report and revealed the company had hid safety information from inspectors by maintaining two sets of safety records.

The operation, which has been closed since the incident, is now owned by Alpha Natural Resources. The company is still reviewing the incident.