By TIM HUBER
The Associated Press
Thursday, September 30, 2010; 6:40 PM
CHARLESTON, W.Va. -- Federal investigators damaged evidence in the deadly explosion at West Virginia's Upper Big Branch coal mine, owner Massey Energy Co. charged Thursday.
Federal Mine Safety and Health Administration investigators intentionally disturbed a 36-foot crack found near the cutting head of a mining machine at the mine's main production section, Massey said. The action damaged "a vital piece of evidence," Massey charged in a lengthy letter released to update its version of the investigation.
MSHA and West Virginia's mine safety agency are conducting a joint civil investigation of the April 5 explosion, which killed 29 miners and injured two. The blast - the worst at a U.S. coal mine since 1970 - also is the subject of a federal criminal probe. Government investigators suspect the blast started with methane and raced through the mine as it fed on loose coal dust.
Massey maintains the crack probably unleashed a flood of methane that overwhelmed safeguards at the underground mine 51 miles south of Charleston. The letter also repeats Massey's accusations that MSHA forced the company to weaken the mine's ventilation system by reducing air flows in the months before the blast and barring the use of dust collecting devices known as scrubbers.
Massey had been cited several times for safety violations involving scrubbers at Upper Big Branch, according to MSHA records.
"Despite our repeated efforts to engage with MSHA and persuade it to allow Massey to turn the scrubbers back on, the agency has refused," Massey said.
MSHA and the company have engaged in a public war of words for months.
MSHA officials have dismissed the crack as a factor in the explosion, though they say methane could have entered the mine through another crack.
MSHA spokeswoman Amy Louviere said Thursday the crack appeared to be the result of normal geologic stress.
"Whether or not the crack was a source of methane will be examined as part of the investigation," Louviere said. "However, there's no reason for anyone to die because of a methane inundation. Adequate ventilation can ensure that methane does not reach dangerous levels."
Massey's letter also conceded "mistakes" at the mine.
"We have discovered mistakes that were made at UBB and have moved to fix them. While we do not believe these mistakes contributed in any way to the accident, we are disclosing them in the interests of transparency and accountability," Massey said.
The letter cited two mistakes that Massey said didn't violate the law and one that did: bringing equipment into parts of the mine where it's not allowed. Massey said MSHA broke the same rules: "This may have been the result of confusion for some people who may not have known that recent ventilation changes had altered what was permissible," the company said.