The report – 613 pages including appendices – was released to the public Wednesday afternoon after a closed-door gathering with the families of the dozen miners who lost their lives.
MSHA has estimated the pressure behind the explosion that occurred at Sago’s sealed area to be 93psi, well above the federally regulated 20psi that was instilled 15 years ago.
“The 20psi standard for underground seals that MSHA put in place in 1992 was inadequate to protect miners,” said agency assistant secretary Richard Stickler.
“We already have increased the strength requirements for new alternative seals to 50psi and are aggressively pursuing regulatory action to require mine operators to take additional steps to protect miners from the dangers of explosions in sealed areas.”
The agency said that it joined Sandia National Laboratories as part of its examination to see if lightning striking the surface could travel underground.
“Three lightning strikes were recorded about the time of the explosion,” the two said. “The bolts struck between one to five seconds before the effects of the explosion were registered by nearby seismographs.”
MSHA said the electromagnetic energy found within lightning could indeed have travelled through the earth to Sago’s sealed section.
“Sandia also determined that this energy induced on an abandoned cable was sufficient to ignite the accumulated methane in the sealed area where the explosion occurred,” it added.
Sago owner International Coal Group released a statement as well on Thursday afternoon, disclosing a significant point to the public – it had not yet been given a copy of MSHA’s report document for review.
However, company president Ben Hatfield said, “The MSHA report seems to be consistent with the findings of three earlier investigations of the Sago accident in concluding that the explosion was most likely caused by a lightning strike rather than human error."
He noted that the three reports – by MSHA, the United Mine Workers of America (UMWA) and the West Virginia Office of Miners’ Health, Safety and Training (WVOMHST) – have brought together many industry and technical experts but that all of their findings are, on many points, similar or identical.
“We hope this report provides some of the answers that the families of the accident victims need and deserve,” Hatfield said.
He reaffirmed ICG’s commitment to cooperation with authorities and support of the killed workers’ families.
“Over a year ago, we pledged to the Sago families and employees that we would learn lessons from this tragedy that will make all coal mines safer in years to come,” Hatfield said.
“Since that time, we have made good progress on this front, including actively participating in testing new wireless communication systems, implementing mine evacuation plans when approaching lightning could pose an ignition risk, and leading industry efforts by being the first US coal company to order emergency rescue shelters for its underground mines nationwide.
“We will continue to support safety innovations and cutting-edge technological advances that enhance coal mine safety and help to protect future generations of coal miners.”
During its investigation, MSHA cited Sago and ICG for 149 regulatory violations. None, however, were contributory to the miners’ deaths, the agency said.
