(CBS/AP) An executive of the Utah coal mine where six men have been trapped since Monday says the rescue effort suffered a huge setback late Tuesday when unstable conditions he attributes to seismic activity forced a total shutdown of rescue activity underground, wiping out the work that had already been done.
"We are back to square one underground," said Robert E. Murray, chairman of Murray Energy Corp., owner of the Crandall Canyon mine, adding that "we should know within 48 to 72 hours the status of those trapped miners."
CBS News correspondent Cami McCormick reports rescue crews are drilling two holes into the mountain in an effort to make contact with the miners and provide them with food and water.
"There is absolutely no way that through our underground rescue effort we can reach the vicinity of the trapped miners for at least one week," Murray said.
The trapped miners are believed to be about three and a half miles inside the mine, which is 140 miles south of Salt Lake City. Rescuers were able to get within 1,700 feet Monday but had advanced only 310 feet more, Murray said around midday Tuesday.
At the time of the collapse, they were working at the end of a tunnel, which then became blocked by about two thousand feet of rubble.
In a private meeting Tuesday with relatives of the miners, Murray outlined plans to bulldoze a mountain path and install a seismic listening device outside the mine that could reveal whether any men were alive.
Once the device is in place, crews will set off dynamite, a sign to miners to tap the ceiling with hammers.
Murray has insisted the cave-in was caused by an earthquake. But government seismologists have said the pattern of ground-shaking picked up by their instruments around the time of the accident Monday appeared to have been caused not by an earthquake, but by the cave-in itself.
Murray lashed out at reporters for suggesting his men were conducting "retreat mining," a method in which miners pull down the last standing pillars of coal and let the roof fall in.
"This was caused by an earthquake, not something that Murray Energy... did, or our employees did, or our management did," he said, his voice often rising in anger. "It was a natural disaster. An earthquake. And I'm going to prove it to you."
According to the National Earthquake Information Center in Colorado, ten seismic shocks have been recorded since the collapse, but only one since 3 a.m. Tuesday. That one struck at 3:42 p.m. with a magnitude of 1.7.
This is not Murray's first time dealing with the media. With mines in at least six states, Murray Energy is one of the largest family-held independent coal producers in the U.S. Its corporate political action group has supported GOP candidates for the Senate and House and Murray himself is politically active, testifying before a House committee several years ago on behalf of proposed changes in the tax code.
Amy Louviere, a spokeswoman for the federal Mine Safety and Health Administration in Washington, said the men were, in fact, engaged in retreat mining.
Retreat mining has been blamed for 13 coal mining deaths since 2000, and the government requires mining companies to submit a roof control plan before beginning retreat mining. Such a plan details how and when the pillars will be cut and in what order.
Louviere says the company had submitted such a plan, and received approval for it in 2006.
Louviere said that exactly what the miners were doing, and whether that led to the collapse, can only be answered after a full investigation.
"As long as they abide by that plan, it can be a very safe form of mining," she said. "What we've found with recent fatalities that the operator was found to not be following the roof control plan."
CBS News correspondent John Blackstone reports the Crandall Canyon mine has been cited for safety violations more than 300 times since 2004. This year, the mine received 32 citations, a dozen of them serious, including one last month for not having the required emergency escape routes.
That record, however, is slightly better than the industry average.
Those in coal country say mining is dangerous work, but it is also essential.
"This is what we do," says Julie Jones, a city councilwoman in Huntington, ten miles away, where many of the miners live. "That's why you get to turn on your lights. That's why you get to turn on your microwaves. That’s why you get to turn on your TVs, because our guys dig the coal for your electricity."
Rescuers do not know whether the men are dead and alive, and have not heard any pounding from hammers, as miners are trained to do when they get trapped.
"The Lord has already decided whether they're alive or dead," Murray said. "But it's up to Bob Murray and my management to get access to them as quickly as we can."
Murray said if the men were not killed by the cave-in, he believes there is enough air and water for them to survive for days. The government's chief mine inspector in the West is not as confident.
"We're hoping there's air down there. We have no way of knowing that," said MSHA's Al Davis.
During a rambling and often angry news conference, Murray lashed out at The Associated Press for suggesting the men were retreat mining at the time.
"The damage in the mine was totally unrelated to any retreat mining," Murray said. "The pillars were not being removed here at the time of the accident. There are eight solid pillars around where the men are right now."
On Monday, seismograph stations recorded seismic waves of 3.9 magnitude, and authorities briefly thought the ground shaking was an earthquake.
But the University of Utah Seismograph Stations and Jim Dewey of the U.S. Geological Survey in Denver said it appeared the trembling was the cave-in.
Quakes caused by mine collapses have a seismic signature distinct from natural ones in that they tend to occur at shallower depths and at different frequencies.
Little information has been made public about the six miners; only one has been identified. The Mexican Consulate in Salt Lake City says three are Mexican citizens.
In Huntington, residents are anxious for news, and the strain could be seen in their somber looks. The families of the trapped miners have been sequestered at a junior high school in Huntington, as police stand guard nearby.
LaRena Collards, 71, has been making cakes for families of the trapped miners, just as she did in 1984 when a fire killed 27 people at another mine.
"You just ask the Lord to bless the families and give them the strength to get through this," Collards said.
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