How US mine tragedy unfolded

SAGO MINE BLAST AND RESCUE ATTEMPT

• 1: At around 0630 local time Monday workers head to work in mine when power fails, apparently because of explosion. Six-man crew heads back to surface to raise alarm, but 13 others trapped.
• 2: Exact location of explosion unknown, but thought to have occurred in disused and sealed section of mine, which has extensive network of shafts because coal extracted from "rooms" with "pillars" of coal left to support roof. Blast possibly caused by lightning reaching build-up of methane gas.
• 3: Late Tuesday rescue teams, working in difficult conditions amid high levels of deadly carbon monoxide gas, find body of man who had been working on coal conveyor belt 11,250ft (3,429m), or 2.1 miles (3.4km), from mine entrance.
• 4: Transporter vehicle, abandoned by 12-man crew, is found 700ft (210m) from body.
• 5: Rescuers drill small holes down from surface to expected position of trapped miners. Tests show poor air quality, although camera reveals tunnel intact.
• 6: All but one of trapped miners found dead behind heavy cloth barricade, put up in attempt to keep out carbon monoxide-laden air. Exact location and distance from tunnel entrance unknown.

• SOURCES: AP; AFP; Reuters; United Mine Workers of America

RELATED INTERNET LINKS
Federal Mine Safety
International Coal Group
United Mine Workers of America
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