Holmes Mill, Ky. – Mine safety officials say a sealing material used at a southeastern Kentucky mine where an explosion killed five miners is an easy and cost- effective way to contain combustible gases, but others in the industry say convenience comes at a cost.
Critics say the material, similar to plastic foam, puts miners in danger and should be banned. Rescuers reported that the seals did not withstand Saturday’s blast at the Kentucky Darby Mine No. 1.
The foam blocks seal out methane and other gases that occur naturally in previously mined areas, and they are often used instead of conventional concrete blocks.
But now state and federal officials are trying to determine whether the foam seals work as well as concrete.
“That’s the question: Are these things leakier than concrete blocks?” Chuck Wolfe, spokesman for the state Environmental and Public Protection Cabinet, said Tuesday. He also wondered whether the sealing has been performed properly at mines that use the alternative blocks.
Mine operators like to use the foam seals because they are cheaper and lighter than concrete, Wolfe said.
But Tony Oppegard – former general counsel for the Kentucky Department of Mines and Minerals, who now represents coal miners – said the alternative seals endanger miners.
“We don’t believe (alternative seals) can withstand the pressure of an explosion as the concrete ones do,” Oppegard said.
Federal regulations require sealing blocks to withstand 20 pounds per square inch of force during a blast.
The alternative blocks failed in both the Darby mine and the Sago Mine in West Virginia, where a January explosion killed 12, and now officials are asking whether federal regulators should raise the threshold for alternative seals.
Alternative seals are common, but most coal operators still use concrete, said Chris Hamilton, head of the West Virginia Coal Association and a member of a mine safety task force assembled after the Sago disaster.
Late Monday, the federal Mine Safety and Health Administration said it would require concrete seals while the issue is reviewed.
Kentucky Gov. Ernie Fletcher said thousands of such seals may be in use.
Federal and state investigators entered the Darby mine Tuesday. Concerns about flammable methane and poisonous carbon monoxide gases had kept them out until the mine’s ventilation system could be repaired.
The mine was cited 41 times in the past five years for not cleaning up coal dust and other combustible materials, including three times this month, according to the Mine Safety and Health Administration.
Since Kentucky Darby LLC took over as operator of the mine in May 2001, there had been 10 injuries but no deaths until Saturday’s blast.
