W. Virginia mine rescuers still hindered

The levels of toxic gases are still too high in a West Virginia mine to permit rescue crews to resume their search for four workers thought to be trapped inside, a U.S. federal official said Thursday night.

Kevin Stricklin of the Mine Safety and Health Administration saiddangerous quantities of methane inside the mine have diminished, but not enough to permit the rescue effort to resume.

Crews have been trying to vent the explosive gas by drilling into the mine, and if that doesn't work fast enough, they will start pumping nitrogen underground to neutralize the atmosphere, Stricklin said.

An explosion Monday at the Upper Big Branch Mine-South, about 50 kilometres south of Charleston, W. Va., killed 25 miners. Four are still unaccounted for, and it is hoped they secured themselves inside a safety capsule within the mine.

Earlier Thursday evening, the governor of West Virginia said he was hopefulrescuers wouldbe able to re-enter the mine by late Thursday night.

"They don't have the margin of safety right now to say that they can go," Joe Manchin told reporters at anews conference. "There's still a certain amount of risk, but it's trending in the right direction."

Rescuers spent four hours attempting to reach thesecurecapsule Thursday morning,but they could only get within 150 metres ofit before being forced to turn back by persistently high gas levels.

Crews then resumed drilling vent holes.

The miners are thought to be trapped about 335 metres below ground. The safety capsule has enough food, water and oxygen to keep them alive for four days.

Obama wants answers

As the rescue effort faltered, more questions emerged Thursday about the safety record of the company that owns the mine.

The facility, which has a long history of safety violations, is operated by Performance Coal Co., a subsidiary of Virginia-based Massey Energy Co., the fourth-largest coal-mining company in the United States.

Massey Energy Co. was fined more than $382,000 in the past year for repeated serious violations involving its ventilation plan and equipment at the Upper Big Branch Mine. The company was also ordered 61 times in 2009 and 2010 to close all or parts of the facility because of safety concerns, according to documents from the U.S. Mine Safety and Health Administration, or MSHA.

One violation cited by the MSHAresultedfrom an inspection last month. A follow-up inspection nine days later found the company had done nothing to resolve the problem, the MSHA said.

The news prompted U.S. President Barack Obamato pressfederal officials for answers about what caused the West Virginia disaster and what should be done to prevent similarcatastrophes in the future.

Obama has asked Labour Secretary Hilda Solis and Mine Safety and Health Administrator Joe Main to review the Upper Branch mine's safety record before he meets with them next week.

CEO calls rules 'nonsensical'

Massey CEO Don Blankenship has strongly defended the company's record and disputed accusations from miners that he puts coal profits ahead of safety.

But in an interviewlast June for theweb series Focus Washington that surfaced this week, Blankenship says that "so many of the laws" on mine safety are "nonsensical from an engineering or coal mining perspective."

"A lot of the politicians, they get emotional, as does the public, about the most recent accident, and it's easy to get laws on the books," he continues.

Blankenship's stance provoked a firm rebuke Thursday from Cecil Roberts, president of the United Mine Workers of America union, which doesn't represent any employees at the Upper Big Branch Mine.

"I've seen where Massey's CEO, Don Blankenship, equates criticizing his or Massey's safety record to being against coal and coal jobs," Roberts said in a statement. "I'm here to tell Don that's bull."

Roberts added that his union has tallied 45 deaths at Massey-owned mines in the last 11 years.

"No other coal operator even comes close to that fatality rate during that time frame," Roberts said. "That demands a serious and immediate investigation by MSHA and by Congress."

The confirmed death toll of 25in Monday's explosion is the highest in a U.S. mine disaster since 1984, when 27 people died in a fire at a mine in Orangeville, Utah. If the four missing bring the total to 29, it will be the worst U.S. coal mining disaster since a 1970 explosion killed 38 in Hyden, Ky.