BUCKHANNON, W.Va. - The force of a blast inside the Sago Mine was too strong for the design of the wall built to seal off an abandoned section of the mine, and while lightning caused the blast, investigators still don't know how it got underground a state report says.Sago Mine report, Post-Gazette
View into the number three entry barricade. The case of SCSRs in right foreground was brought by mine rescue teams for use in evacuation of survivors -- some were used for evacuating Randal McCloy Jr.
Click photo for larger image.
The report - scheduled for release and then withdrawn - by the West Virginia Office of Miner Health Safety and Training, says lightning was the cause of the blast, though it cannot determine how it reached two miles into the mine. Additionally, investigators continue to look into what role, if any, an electrical cable on an abandoned pump in the sealed area might have played.
While Gov. Joe Manchin III ordered the report withheld after meeting with families of the 12 miners who died in the Jan. 2 accident, a copy was obtained today by the Post-Gazette.
The report says that although lightning caused the explosion, "our work is not complete until the specific mechanisms which allowed lightning to enter behind the seals at the Sago mine have been identified."
The state office of Miner Health Safety and Training, which compiled the report, recommended monitoring at Sago this winter for any lightning effects in the area.
The report also suggested that bottom-mining in the area behind the seals - the harvesting of coal from a second seam beneath the mine floor - may have played a role in increasing the force of the explosion. It calls for additional studies of whether it increased the volume of methane behind the seals. Computer modeling was proposed.
The voluminous report was set for release at a 1:30 p.m. meeting today in Buckhannon, the largest city near the mine, when state officials pulled it back.
Caryn Gresham, a spokeswoman for MHST, said about 50 family members met in Buckhannon where they were given a presentation on the report.
Gov. Joe Manchin III was at the meeting and decided to postpone its release after family members expressed concerns about the document.
"It's an emotional issue for them and it's getting near the anniversary" of the disaster, Ms. Gresham said.Sago Mine report, Post-Gazette
Randal McCloy Jr's. hat and several of the SCSRs used by the rescue team as they provided aid while bringing him out
Click photo for larger image.
She said family members had questions about technical aspects of the report, asked for more visuals to aid in understanding the document, and some family members also asked about the Omega seals.
"Some of these things we're still doing testing on," Ms. Gresham said.
It is likely, she said, that the report will be rewritten to accommodate these questions.
Word that the state would conclude lightning was the cause of the blast, despite evidence on how it traveled more than two miles to reach the point behind the seals, was widely reported last week.
Today's newer revelations include suggestions that the Omega Block walls were not constructed consistent with the approved plan. Two of the walls, it says, should have had a pilaster - a reinforcing support column of extra blocks - built in its middle. The report also faults the construction because the blocks were laid atop dry mortar, rather than fixed to the floor with mortar, and the failure to apply mortar in several other places.
"Conditions of the sample taken ranged from dry powder to semi-cured mortar," the report said. Preliminary testing, however, found that the seal construction methods were capable of withstanding 20 pounds per square inch, the government minimum.
The emergency breathing devices used by the doomed miners - known as self-contained self-rescuers, or SCSRs - apparently all produced oxygen, but in differing amounts. The report also offers the surprising declaration that the area in which the men barricaded themselves to await rescue, apparently had breathable levels of oxygen, but was polluted by carbon monoxide.
"Those that perished in the 2nd-left barricade did so in an atmosphere that had sufficient oxygen to sustain live but also contained toxic levels of carbon monoxide," the report states.
Matching SCSRs to the miners who used them might have proven difficult for investigators, who found that no checks were in place to ensure that miners did not pick up the wrong SCSR in the bathhouse.
"It would not be unusual that every miner underground would have an SCSR but not necessarily the one assigned in the company logs," the report states.
While surviving miner, Randal McCloy Jr., said the some miners' SCSRs failed to provide adequate oxygen, the report cannot reach a conclusion on that. It does say that currently acceptable training doesn't give miners the knowledge they need to decide when to use the devices and that mines "need more emergency breathing options to encourage escape and provide protection when barricading."