The families of six trapped miners are "waiting for a miracle," their spokesman said, as rescuers made one last attempt to find the missing men and lawmakers in Washington announced twin probes into safety at the mine.

Sonny Olsen, an attorney acting as spokesman for the families, said late Thursday that the families had lost some of their hope that the miners would be found alive. "But they're waiting for a miracle," he said. "These families believe in miracles."

In a sign of how desperate the families have become, organizers planned a benefit Friday night to raise money to drill a hole big enough for a rescue capsule. "Leave no man behind," said a flier publicizing the event. Such capsules have been used to save miners in other disasters, but the men in the Crandall Canyon mine are thought to be more than 1,000 feet deeper than in previous rescues.

Sen. Edward Kennedy, chairman of the Health, Education, Labor and Pensions Committee, demanded a litany of documents from the Labor Department about the mine and its operators.

Kennedy, D-Mass., said he was troubled by reports of past collapses at the mine that "may not have been reported to (Mine Safety and Health Administration) regulators as required by law. Such reports raise questions about the integrity of the mine operator's reporting and the rigor of MSHA inspections."

The six miners have been trapped since Aug. 6, and searchers have found no sign they survived. Three other miners were killed and six more injured last week when the shifting mountain crumbled around them as they tunneled toward the missing men. Tunneling has not resumed.

Kennedy wants to review several petitions the mine's co-owner, Bob Murray, made to the MSHA for changes in his mining plans at Crandall Canyon, among other documents. Experts have said the proposed changes were risky and could have led to the initial collapse.

The Senate Appropriations subcommittee that oversees labor issues announced plans for a hearing on the mine collapse when Congress returns from its summer break Sept. 5. The subcommittee wants to question Murray and MSHA chief Richard Stickler.

Officials with Murray's company did not return repeated requests for comment Thursday.

At the mine, crews worked on a sixth test hole to try to locate the men. MSHA said no air samples or video images could be obtained from the fifth hole because it became plugged with mud.

Other holes provided only grainy video images of rubble and poor air sample readings, and efforts to signal the miners have met with silence.

The sixth hole will head toward an area where the miners were last believed to have been working, some 1,500 feet below the surface. It was expected to be completed over the weekend.

Murray has said it will be the last hole.

But Olsen said the families want drilling to continue even if the sixth hole fails to show signs of life. If rescue is not possible, the families want the men's bodies to be retrieved.

"Sealing up the mine with our loved ones inside without knowing if they've perished is outrageous to us," said Olsen, reading from a statement. "There's been no indication that these men are not alive. The families acknowledge that there's an issue with the air. These men are trained on how to survive in these kinds of environments."

Gov. Jon Huntsman said Thursday the families of the missing men needed peace of mind.

"I do think the way the families have been treated is unconscionable," he said.

Murray has made a series of conflicting statements about whether mining will ever again take place at the mine, or elsewhere on the mountain.

He said the mine would be sealed and digging would cease where the miners are trapped but that there are reserves in other sections of the 5,000-acre mine that could be tapped.