In the documentation provided to ILN, the agency said a track-based locomotive at Consol's Robinson Run No. 95 operation, with lead motorman Garry Hoffman inside, derailed and travelled about 175ft before coming to a stop last Thursday afternoon.

Hoffman was transporting two flats of supplies along the mine's 3 West track haulage at the time.

"The motorman stopped on two occasions to obtain clearance from the mine dispatcher and refilled their sanders on both occasions," according to the report.

"The last verbal contact with the victim was at an electric derail switch at the No. 101 block."

MSHA added that the tail motorman, Richard Carson, was about 300–400ft behind Hoffman and after noticing visible dust from the derail, he attempted contact with the victim but received no response.

The state's Office of Miners' Health, Safety and Training told the Associated Press that officials are testing the locomotive for mechanical or electrical problems.

The fatality was the third underground in a one-week span in the US.

On May 30, general labourer Adam Lanham, 18, was working at International Coal Group's Wolf Run Mining Sentinel mine in West Virginia when he was struck by a battery-operated scoop.

Tuesday morning, roof bolter operator Justin Wilkin, 25, was working at Gibson County Coal's Gibson operation in Indiana when a section of unsupported roof fell on top of him.

The Robinson Run mine is staffed by about 500 workers and produces 7 million tons per year.