Blankenship and other company officials have vigorously defended themselves, saying Massey is a national leader on safety and never puts production ahead of protecting miners. Still, some shareholder groups have complained that Blankenship's leadership has not put safety first, and amid the disaster's aftermath, the Massey's board is exploring various potential changes, including a sale of the company.

Blankenship has announced that all of Massey's underground mines will close for the day on Friday for increased safety training and mine safety examinations, following a series of tough enforcement actions by MSHA and the disciplining of a number of miners and mine supervisors.

Blankenship said the company has more than doubled -- from 20 to 50 -- the number of employees dedicated to "internal inspections" across the company and rewritten all underground job descriptions so safety expectations and accountability are made more clear.

"We're doing everything we can to comply better than anyone in the industry," Blankenship said. "We will outperform the industry."

Also Wednesday, Massey officials continued their campaign to discredit MSHA's investigation of the Upper Big Branch disaster and to argue that a buildup of coal dust underground did not contribute to the tragedy.

Blankenship said that the company's "preliminary computer models" support the theory that the explosion occurred when a tunnel called the "tailgate entry" was flooded with methane gas. "We do not believe that coal dust was a meaningful factor," Blankenship said.

Shane Harvey, Massey's general counsel, said Massey has other evidence the company will "elaborate on in the future" that supports that view.

MSHA investigators have argued that the disaster was made far worse when high levels of coal dust allowed the explosion to carry from its point of origin far out toward the mine mouth. Agency officials cited the fact that 79 percent of the more than 1,800 dust samples taken from inside the mine showed inadequate levels of crushed limestone, or rock dust, meant to control dust ignitions.

Harvey said the company has evidence "showing that the levels of rock dust and coal dust in the mines were affected by the explosion, making MSHA's samples invalid" just as a federal judge ruled similar samples were after an Alabama coal-mining disaster in 2001.

MSHA has declined to answer questions about how its rock-dust sampling procedures or testing methods were different than those that were discounted after that 2001 disaster, an explosion that killed 13 miners at the Jim Walter Resources No. 5 Mine near Brookwood, Ala.

Reach Ken Ward Jr. at kw...@wvgazette.com or 304-348-1702.

CHARLESTON, W.Va. -- Massey Energy CEO Don Blankenship on Wednesday continued to defend his company's safety record, saying Massey "has a totally clear conscience" about an explosion at the company's Upper Big Branch Mine that killed 29 miners in April.

Blankenship also said Massey and its experts continue to develop evidence that discredits the view of federal investigators who believe a buildup of coal dust underground made the April 5 explosion far worse that it otherwise would have been.

Massey Energy officials continued to complain about increased federal safety inspections and enforcement they said had reduced the company's productivity by 30 percent and cost Massey 230,000 tons of coal production during the three months that ended Sept. 30.

Massey executive also blamed a $41.4 million loss during the quarter in large part on delays in U.S. Mine Safety and Health Administration mining plan approvals, which the company said delayed production and shut down hundreds of mining shifts entirely.

Blankenship declined to comment on whether Massey was being specifically targeted in an MSHA crackdown, but said that increased focus by regulators on the company was to be expected following the mine disaster in Raleigh County.

But Blankenship said he's not concerned about increased scrutiny in the investigation of Upper Big Branch or by MSHA inspectors who are tightening enforcement following the worst U.S. coal-mining disaster in 40 years.

"We have a totally clear conscience in that we know what we have done relative to safety," Blankenship told industry analysts in a quarterly conference call. "We don't believe we contributed in any way to the accident."

Still, MSHA officials confirmed that they had turned down Massey's request to open a new mine adjacent to Upper Big Branch to mine some of the same reserves it had planned to mine with the operation where the explosion occurred.

MSHA spokeswoman Amy Louviere noted that the investigation of the explosion is ongoing and that the area covered by a federal "control order" for the probe is where Massey wanted to resume mining.

Louviere said MSHA is also concerned that the ventilation plan submitted by the company for that area was inadequate.

"The area Massey wants to mine is in the same seam where the explosion occurred," Louviere said in an e-mail message. "Given the events surrounding this disaster, our first concern must be the safety of the miners. Massey needs to address these concerns in their plan before MSHA will grant approval."

Massey's safety record, already the subject of much criticism, has been under increased scrutiny since the Upper Big Branch explosion.

Blankenship and other company officials have vigorously defended themselves, saying Massey is a national leader on safety and never puts production ahead of protecting miners. Still, some shareholder groups have complained that Blankenship's leadership has not put safety first, and amid the disaster's aftermath, the Massey's board is exploring various potential changes, including a sale of the company.

Blankenship has announced that all of Massey's underground mines will close for the day on Friday for increased safety training and mine safety examinations, following a series of tough enforcement actions by MSHA and the disciplining of a number of miners and mine supervisors.

Blankenship said the company has more than doubled -- from 20 to 50 -- the number of employees dedicated to "internal inspections" across the company and rewritten all underground job descriptions so safety expectations and accountability are made more clear.

"We're doing everything we can to comply better than anyone in the industry," Blankenship said. "We will outperform the industry."

Also Wednesday, Massey officials continued their campaign to discredit MSHA's investigation of the Upper Big Branch disaster and to argue that a buildup of coal dust underground did not contribute to the tragedy.

Blankenship said that the company's "preliminary computer models" support the theory that the explosion occurred when a tunnel called the "tailgate entry" was flooded with methane gas. "We do not believe that coal dust was a meaningful factor," Blankenship said.

Shane Harvey, Massey's general counsel, said Massey has other evidence the company will "elaborate on in the future" that supports that view.

MSHA investigators have argued that the disaster was made far worse when high levels of coal dust allowed the explosion to carry from its point of origin far out toward the mine mouth. Agency officials cited the fact that 79 percent of the more than 1,800 dust samples taken from inside the mine showed inadequate levels of crushed limestone, or rock dust, meant to control dust ignitions.

Harvey said the company has evidence "showing that the levels of rock dust and coal dust in the mines were affected by the explosion, making MSHA's samples invalid" just as a federal judge ruled similar samples were after an Alabama coal-mining disaster in 2001.

MSHA has declined to answer questions about how its rock-dust sampling procedures or testing methods were different than those that were discounted after that 2001 disaster, an explosion that killed 13 miners at the Jim Walter Resources No. 5 Mine near Brookwood, Ala.

Reach Ken Ward Jr. at kw...@wvgazette.com or 304-348-1702.