According to the US Mine Safety and Health Administration, on June 16, 2010, the 42-year-old foreman and several crew members were standing in an intersection discussing control measures for the left inbye rib corner, which had fallen into the roadway.
While the discussion was occurring, a portion of rib fell from the right outbye corner, dislodging two of the three roof jacks that had been installed to limit the entry width where the corner had previously fallen out.
One of the roof jacks dislodged by the fallen rib struck the victim, resulting in fatal injuries. The fallen rib measured about 12 feet wide, 15.5ft high and 9ft thick.
Order no. 8347228 was issued verbally to the Clover Fork No. 1 mine on June 16 under section 103(j) of the Mine Act and modified to a 103(k) order the same day.
Citation no. 8403819 was issued by MSHA for a violation of 30 CFR section 75.202(a), according to a report of the agency’s investigation into the accident.
“The roof, face and ribs of areas where persons work or travel were not supported or otherwise controlled to protect persons from hazards related to falls of the roof, face or ribs,” MSHA said in the report.
“The outbye right rib corner of the pillar in the No. 2 entry intersection at survey station #2660, located on the 001 section, fell at approximately 3.43pm on June 16, 2010, dislodging a Heintzmann jack that struck a miner in the head, causing fatal injuries.
“The height in this intersection measured 16 feet. A portion of this rib corner had previously fallen out and had been cleaned up, but additional rib support had not been installed. Section foreman Bill Wilson stated on June 17, 2010, that at least a week prior to the fatal accident, his crew had reset one of the three Heintzmann jacks that had been installed to reduce the width to a maximum of 20 feet because it had been knocked out by a piece of diesel equipment.
“Therefore, the operator had reason to know that the unstable rib had not been supported.
“This constitutes more than ordinary negligence and is unwarrantable failure to comply with a mandatory standard.
“This standard was cited 46 times in two years at this mine.”
