The accident was the worst in an American mine since Dec. 19, 1984, when 27 workers died in a fire at the Wilberg Mine in Orangeville, Utah, and it came just four years after federal regulators enacted a sweeping overhaul in mine safety laws. That overhaul, the first in over three decades, came after 19 miners died in a series of mine accidents in West Virginia and Kentucky — including one that brought criminal charges against a Massey subsidiary.Just a month ago, the mine was found to not be in compliance with mining safety rules, including proper ventilation and mitigation of methane gas. Despite a massive overhaul of mine safety rules four years ago, companies are still skirting the rules, and enforcement by government regulators is anything but assured.
The explosion occurred about 3 p.m. Monday at the Upper Big Branch mine, 30 miles south of Charleston, in Raleigh County.
The mine, which employs about 200, is owned by the Massey Energy Company, based in Virginia, and operated by the Performance Coal Company.
Mine safety officials said that there were three groups of miners affected by the blast. One group consisted of nine miners who were leaving the site at the end of their shift in a vehicle known as a “mantrip.” Seven of the miners in the man trip were killed by the explosion while two others were injured and taken to the hospital by rescue workers.
A second group of 18 miners was said to be working a bit deeper in the mine, closest to the area where coal was actually being extracted. All 18 of them died.
A third group of four miners — the ones still unaccounted for — was even deeper in the mine.
The miners were all thought to be working more than 1,000 feet underground.
The explosion on Monday destroyed all communication lines inside Upper Big Branch, but Kevin Stricklin, an administrator with the Mine Safety and Health Administration, said there were two rescue chambers near the blast site. If the miners could reach them, the chambers were stocked with food, water and enough air to allow them to survive four days.
Mr. Stricklin said that officials did not think there had been a roof collapse, but that they did not know what had caused the explosion in the sprawling mine. Upper Big Branch, which cannot be seen from the road, has 19 openings and roughly seven-foot ceilings, federal safety officials said.
The mine had been fined more than $1.5 million, but had paid only a fraction of the fines imposed by the U.S. Mine Safety and Health Administration (MSHA).
Meanwhile, rescuers were attempting to drill three shafts into the mine to vent methane and carbon monoxide.