TORONTO (miningweekly.com) – Federal mining officials cited US miner Patriot Coal on Tuesday for three serious violations they said led to an accident called a ‘coal burst’, that killed two miners at the West Virginia Brody Mine No 1, in May.

The US Department of Labour’s Mine Safety and Health Administration (MSHA) blamed Patriot for not protecting miners from the hazardous conditions associated with a coal burst, failing to report a similar burst three days earlier and for not preserving the earlier coal burst site as evidence.

On May 12, Eric Legg (48) of Twilight and Gary Hensley (46) of Chapmanville, were the victims of a coal burst, also known as bumps or outbursts – sudden and violent failures of overstressed rock or coal, resulting in an instantaneous ejection of material into mine openings. When such events take place in active workings, they pose a serious hazard to miners.

The miners were busy with one of the most dangerous mining techniques – retreat mining – which involved extracting coal while leaving behind pillars for support, then returning to mine the pillars in a precise sequence that caused the roof to collapse as mining ‘retreated’ toward the mine’s entrance. The pillar burst caused a large amount of coal from the mine ribs, or walls, to be suddenly and violently ejected into the mine entry, filling the entry close to the mine roof.

According to the federal report, rescue workers could hear Hensley crying for help. He was unresponsive when help reached him and removed the mining equipment that had trapped him.

The previous coal burst on May 9 knocked down a worker, covered him in coal up to his mid-thigh and trapped him for less than five minutes until help arrived. He had some bruises and stiffness in his leg, but refused medical attention and reported for work the next day. The accident was not reported to the MSHA.

The MSHA said no previous coal bursts at the Brody mine were reported to the agency or at active mines in the surrounding Eagle Seam region of mines, in Boone County.

Patriot subsidiary Brody Mining had stopped retreat mining at Brody No 1, having ceased all mining in the eastern side of the mine where the accident occurred.

The MSHA had launched an investigation into what other precautions were needed against coal bursts, particularly at deep cover mines with depths exceeding 300 m.

Last month, the West Virginia Office of Miners' Health, Safety and Training (WVOMHST) issued several notices of violation against Patriot for the May 12 coal burst.

In October 2013, Brody Mine was placed on notice of a 'pattern of violations' of mandatory health or safety standards under the federal Mine Safety and Health Act. Since then, the mine operator had reduced its “significant and substantial violation rate by 53%”, the agency said.

In a statement, Patriot on Tuesday afternoon retorted that it believed both the WVOMHST and MSHA reports had omitted key eyewitness testimony and other evidence from the investigation, and mischaracterised certain accounts of the events leading up to and including the tragic accident.

“Most notably, the agencies' characterisation of a rib roll incident on May 9 as a violent mine outburst and a precursor of the devastating May 12 accident contradicts sworn testimony from the majority of eyewitnesses,” Patriot charged.

The company pointed out that Brody intended to “vigorously challenge” the citations and orders that were issued by both agencies in conjunction with the investigation, saying that it would present its account of the events in the matter “in the appropriate legal forum”.