There were warning signs before pillars of coal and rock burst outward and killed an employee at an underground mine in Harlan County last year, but managers did not modify the mining plan, according to a report from federal regulators.
The Aug. 6 accident at Lone Mountain Processing's Huff Creek No. 1 mine near Holmes Mill killed Lenny D. Gilliam, 56, of Appalachia, Va., and hurt two other miners, one seriously.
Employees at the mine, controlled by Arch Coal, were conducting retreat mining when Gilliam was killed. In that process, employees mine pillars of coal that support the roof, allowing it to fall as they work back toward the mine opening.
Lone Mountain had several significant indicators that the mining plan being used was not adequate to deal with the geologic conditions at the accident site, the U.S. Mine Safety and Health Administration said in a report released earlier this month.
In April, MSHA inspectors had given the company a technical report that said retreat mining was "inadvisable" at the spot because of conditions there, according to the federal agency's accident investigation.
However, Lone Mountain did not re-evaluate conditions at the mine or revise its mining plan, according to the investigation.
Another sign of danger came the day before the accident, according to the report, when there was another burst — in which pillars explode because of weight from above.
Also, the company had core-drilling information showing that the roof of the mine consisted of a "massive" slab of siltstone, with sandstone making up the floor. Having hard stone above and below is a condition associated with bursts, MSHA said.
Federal investigators concluded that the company did not mine the coal pillars in a sequence calculated to redistribute weight to barrier pillars. Rather, it first mined the center block, which had the most stress on it.
That created conditions conducive to a burst, the federal report said.
Gilliam was shaving coal from a pillar with a remote-controlled continuous-mining machine, which uses a large studded wheel to grind out coal and rock, when pillars on either side burst, burying him, according to a report from the Kentucky Office of Mine Safety and Licensing.
The burst pinned miner Terry Scott in a machine and knocked down Johnny Nantz, the state report said.
Other miners rushed to help the three. It was so dusty they couldn't see Gilliam, but then they spotted the light on his hard hat and began pulling coal and rock away from him.
Gilliam didn't have a detectable pulse. Foreman Billy Fox began cardiopulmonary resuscitation as soon as he and others had uncovered Gilliam's chest, but he was pronounced dead at the hospital in Harlan, the federal report said.
Scott was flown to a hospital in Tennessee for treatment of serious injuries. Nantz was treated at the Harlan hospital.
Gilliam, a married father of three, had 37 years of mining experience.
The mine where the fatal accident happened had an injury rate well below the national level in 2012, MSHA said.
State and federal regulators cited the company. A spokeswoman for Arch Coal declined comment Monday.