MONTCOAL, W.Va. -- Rescuers continued on Tuesday evening with what they admitted is a long-shot effort to save four Massey Energy miners still unaccounted for after a huge explosion that killed 25 workers, injured two others, and brought more calls for safety reforms in the nation's mining industry.
State and federal regulators and elected officials promised thorough investigations, even as they struggled to maintain a small slice of optimism following the worst U.S. coal-mining disaster in a quarter century.
"We've all thrown everything at this rescue effort," said Joe Main, assistant labor secretary for the federal Mine Safety and Health Administration. "We're going to throw the same effort at getting to the bottom of what happened."
At a 5 p.m. briefing, Massey vice president Chris Adkins said drilling crews could get ventilation boreholes into his company's Upper Big Branch Mine in Raleigh County by noon or 2 p.m. Wednesday. No significant news on the drilling progress was expected until 8 a.m. Wednesday, officials said.
Rescue efforts were abruptly halted early Tuesday morning, when officials detected dangerous levels of methane that presented a risk of another explosion that would endanger rescue teams.
Kevin Stricklin, MSHA's administrator for coal mine safety, said the massive explosion damaged many of the ventilation walls that control the flow of fresh air and keep down methane levels. Stricklin said ventilation fans appear to be working, but aren't providing enough airflow to reduce methane to safe concentrations.
Adkins said he's 90 percent certain where the four remaining missing miners are, and once rescuers can get into the mine, teams should be able to reach them in four or five hours.
"They should be able to blow the mine out pretty well and get the gases under control and then they should be able to advance pretty rapidly," said Joe Pavlovich, a former MSHA official and mine rescue expert.
Gov. Joe Manchin said officials are holding out hope that the four unaccounted-for miners were able to reach an airtight underground rescue chamber with food, water and air that could last them four days or more.
"Everybody is going to cling to the hope of a miracle," Manchin told reporters, while acknowledging that "the odds are against us."
The explosion is believed to have occurred at about 3 p.m. Monday inside the Upper Big Branch Mine, a huge longwall operation that produced 1.2 million tons of coal last year with about 200 workers. The blast occurred near the time for a shift change and some workers were believed to have been on their way out at the time.
Manchin said rescue teams described seeing massive damage underground, including mine car rails that were bent "like pretzels," and others said miners thousands of feet away were killed by the strength of the blast.
Tim Bailey, a Charleston lawyer who represents miners and their families in safety cases, said such damage indicates an initial methane explosion that was made far more powerful by coal dust that had not been properly cleaned out of the mine.
"You get the initial explosion, and it just feeds itself out through the mine," Bailey said.
The Upper Big Branch is considered a "gassy mine," meaning it generates large amounts of methane. Under a provision of federal law, the operation undergoes more frequent inspections, and those inspections have turned up various violations of mine ventilation standards.
In an interview with West Virginia MetroNews, Massey CEO Don Blankenship denied any violations by his company led to the disaster. "Any suspicion that the mine was improperly operated or illegally operated or anything like that would be unfounded," Blankenship said.