In addition, another unwarrantable failure citation was issued for combustible material accumulations at eight sites near a conveyor belt, over a distance of about 220m.

MSHA said the accumulations were “extensive and obvious” after conducting an impact inspection during the first shift on September 24.

Officials went underground and immediately monitored the communications systems to prevent advance notification of the inspection.

They entered the mine by walking in the belt conveyor entry to the mining section and issued 25 citations, one order and one safeguard on the surface area of the mine, the belt conveyors and the continuous mining machine.

This was the first impact inspection at this mine.

Pre-shift and on-shift examinations were conducted in these areas; however, inspectors found that accumulations had been rock dusted without the areas being cleaned and little to no rock dust had been applied to the roof.

These accumulations, along with others found throughout the mine, created fire and explosion hazards to miners. Rock dust is pulverised limestone used to reduce the explosion potential of coal dust and other dust generated during mining operations.

The mine operator also was cited because miners could not text with their communications system, as required by the post-accident portion of the mine’s approved emergency response plan.

Only one of the text devices was operable, and just four of the eight miners were trained on how to use text devices.

Inspectors found that the lifeline, which is a durable, rope-like or rigid flame-resistant material that miners use to guide them out of the mine in the event of an emergency, and other equipment, such as the communication and tracking system’s backup battery, along with a gas detector, were not properly maintained.

Other safety violations found included damaged top rollers on the conveyor belt, inoperative emergency parking brakes on the scoop, uninsulated trailing cable on the continuous mining machine, inadequate guarding on the belt drive and loading point tail roller, and failure to record hazardous conditions during the pre-shift examination of the continuous mining machine and conveyor belt.