The document will be made public April 12 sometime around 9pm local time on the agency’s website, following the briefing of the miners’ families on the report’s contents. The group is gathering at the agency’s district office in Harlan, Kentucky.

“Following the accident at the Darby Mine, an independent team of MSHA mine safety professionals nationwide was assembled to evaluate all aspects of the accident, including potential causes and compliance with federal health and safety standards,” MSHA said in a statement provided to International Longwall News Wednesday.

“The team examined the accident site, interviewed mine personnel and others with relevant information, reviewed records and plans, and inspected any mining equipment involved. The formal report that MSHA will issue summarises the findings and conclusions of the investigative team, identifies root causes of the accident and describes how the incident unfolded.”

MSHA spokeswoman Amy Louviere told ILN in an email Wednesday that while the agency cannot comment any further on the report’s contents at this time, it could confirm that should the meeting end prior to 9pm Thursday the report could be publicly posted earlier than scheduled.

The explosion on May 20 last year took the lives of Jimmy Lee, 33, and Amon Brock, 51, who both died due to blunt force and heat injuries, as well as Roy Middleton, 35, Bill Petra, 49, and Paris Thomas Jr, 53, who all succumbed to carbon monoxide poisoning while attempting to escape from the mine.

“We would expect the federal report to be essentially the same as the state report,” former state and federal mine safety representative Tony Oppegard told the Associated Press. The state’s report pointed to a torch inside the complex that ignited methane.

Keep watching International Longwall News for more information on the report.