Chronology
At 5:30 a.m on November 20, an explosion shook the mine. It was so strong that a motel clerk reported feeling vibrations 12 miles away. Miners living in the area heard the noise and, knowing what it meant, headed to the mine, where they discovered a rapidly-spreading fire with flames shooting 150 feet into the air. Within hours, 21 miners made it to the surface but 78 were still trapped underground.
The fires continued to burn for over a week, and on November 29, rescuers finally admitted defeat after air samples from drill holes showed air unable to sustain human life. The mine was sealed on November 30 with concrete to starve the fire of oxygen.
In September 1969, the mine was unsealed in an attempt to recover the miners' bodies. Progress was slow because workers discovered cave-ins that they had to tunnel around. This recovery effort continued for almost ten years. By April 1978, 59 of the 78 bodies had been recovered. Unable to recover the other 19, the mine was permanently sealed.
The actual cause of the blast and fire was never determined. However, several contributing factors were found that may have caused the blast: inadequate ventilation, inadequate control of explosive methane gas and coal dust, and inadequate testing for methane.
Read more about this topic: Farmington Mine Disaster