Pyro Mining Company
William Station No. 9 Mine Explosion
Sullivan, Kentucky September 13, 1989 No. Killed - 10
At about 9:13 a.m., September 13, 1989, an explosion occurred on Longwall Panel "O" between the 4th and 5th West entries off the first Main North entry, of Pyro Mining Company's Pyro No. 9 Slope, William Station Mine, located at Sullivan, Kentucky.
Fourteen miners were present in the longwall recovery area at the time of the explosion. Ten died as a result of the explosion; four escaped despite being exposed
to high concentrations of carbon monoxide and smoke.
MSHA investigators concluded that the primary cause of the explosion was the failure of management to maintain a sufficient volume and velocity of air in the proper direction in the 4th West entries and longwall face to dilute, render harmless, and carry away methane accumulations in that area. Changes had occurred during the mining of Longwall Panel "O" in the 4th and 5th West entries and in the longwall bleeder ventilation system. The removal of the stopping in the No. 1 cut-through entry between the 4th and 5th West entries disrupted the separation between the 2nd Main North entry's ventilation system and the longwall bleeder system.
These changes decreased the airflow across the longwall face and permitted methane to migrate from the gob and accumulate in the No. 2 entry of the 4th West entries inby the No. 6 crosscut and near the longwall headgate.
This caused an explosive methane-air mixture to flow toward and into the longwall recovery area where it was ignited by one of five probable sources:
Operation or attempted lighting of a cutting torch.
Operation of a scoop tractor.
Detonation of a blasting cap.
Tensile failure of the messenger wire.
Conditions and practices that contributed to the explosion include:
Failure to maintain adequate airflow in proper volume and direction in the No. 2 entry of the 4th West entries inby the No. 6 crosscut, and failure to maintain the proper pressure differential across the Longwall Panel "0" gob in accordance with the approved mine ventilation plan.
Failure to recognize the sensitivity of the bleeder system and the effects of the numerous ventilation changes.
Failure to determine whether the bleeder system was functioning to continuously move methane-air mixtures from the gob, away from the active workings, and deliver such mixtures to the return aircourses.
Failure to maintain curtains in the recovery rooms and in the 4th West entries where permanent stoppings were removed.
Failure to ensure that a preshift examination was conducted in the Longwall Panel "O" recovery area prior to the day shift of September 13, 1989.
Failure to initiate corrective action to determine the source and cause of methane accumulations when explosive concentrations were detected on the Longwall face on Saturday, September 9, 1989.
Failure to take adequate precautions prior to removing the stopping in the No. 1 cut-through entry between the 4th and 5th West entries. The stopping was removed during an active shift with miners in the mine.
Historical Summary of Mine Disasters in the United States - Volume II