Sen. Edward Kennedy, D-Mass., the chairman of the Senate Committee on Health, Education, Labor and Pensions, requested that the Labor Department turn over any documents relating to the Crandall Canyon mine, which has claimed the lives of three rescuers and, likely, six trapped miners. The sweeping documents request includes any inspections of the site, petitions for changes in mining practices and notes and correspondence between federal officials and the various companies associated with the Utah mine operator.

"The loss of life at the mine, and the devastating emotional toll on families of the victims, underscore the urgent need for a thorough examination of our federal system of mine safety," Kennedy said in the letter, noting it was his "duty" to investigate the causes of the tragedy and its aftermath to prevent future tragedies.

The letter signaled the first effort by Congress to review the Mine Safety and Health Administration's approval of the Utah mine's operations, the disaster itself and the rescue effort. Key congressional leaders have vowed a comprehensive investigation.

The Labor Department says it will cooperate with the probe.

"We appreciate Senator Kennedy's interest and concern," a department spokesperson said. "MSHA remains focused on the ongoing efforts at the mine site and will be conducting a full investigation as soon as those efforts are concluded. We look forward to working with the committee on this important matter."

The first hearing on the mine is slated for the day after the Senate resumes its session, Sept. 5, before the appropriations subcommittee, which oversees the budget for the Labor Department.

The panel invited testimony from Richard Stickler, head of MSHA; Bob Murray, co-owner of the Utah mine; Cecil Roberts, head of the United Mine Workers of America; and David McAteer, a former MSHA director.

Sen. Tom Harkin, D-Iowa, who heads the subcommittee, said he held hearings directly after the deadly mine disasters in Sago and Melville in West Virginia to figure out what went wrong to try to avoid future disasters.

"And here we are again after yet another coal mine tragedy," Harkin said in a statement, noting that his father was a coal miner for 23 years and he is committed to preventing further tragedies. "We must get to the bottom of the Utah disaster and implement ways to effectively protect workers."

The Senate held six hearings after the Sago disaster, and Congress passed a sweeping reform bill, the Mine Improvement and New Emergency Response Act, or MINER Act, the largest overhaul of mining regulations in three decades

Still, critics said the bill didn't go far enough and delayed needed reforms too long - a point several politicians have raised since the Utah mine disaster. New measures, which would hasten the installation of underground communication equipment and miner tracking devices, may see swift action in response to the Utah tragedy.

In his letter, Kennedy asked for huge cache of documents, going as far as requesting handwritten notes, calendar entries and e-mails about any meetings between mine operators and MSHA's headquarters and the local field office and correspondence. He specifically asked for documents showing any changes made after Murray's company became part owner of the mine in August 2006.

Murray had insisted that his company did not change the mining plan at Crandall Canyon after the purchase, but documents obtained by The Salt Lake Tribune contradict that claim, showing that his company sought and received approval from federal officials to make significant changes.

Kennedy also asked for any materials concerning changes in mine conditions, including "bumps" or "bounces," industry language for movements of the mountain being mined. Documents have revealed that the operators were using a type of mining known as retreat mining, in which walls of coal are removed, allowing tunnels to collapse.

"I am particularly troubled by reports that roof failures, similar in kind to the August 6 collapse, previously occurred in sections of the mine where retreat mining was being conducted, and that this roof failure may not have been reported to MSHA regulators as required by law," Kennedy added. "Such reports raise questions about the integrity of the mine operator's reporting and the rigor of MSHA inspections."

Kennedy set a deadline of Sept. 6 for the department to reply, but he scheduled no specific hearing on the mine.

The head of the House Labor and Education Committee also plans hearings on the mine disaster.

tburr@sltrib.com