United Mine Workers of America international vice-president Daryl Dewberry told Associated Press 100 employees had returned to work last week, and more were expected back on the job over the weekend.
Longwall operations will be limited for some time as water is pumped out of the mine.
A Mine Safety and Health Administration preliminary report in March attributed Shoal Creek’s explosion and roof fall to an "ignition/explosion [that] occurred when a flammable methane/air mixture was ignited by possible friction during a roof fall in the gob behind the headgate shields". A witness, according to the filing, reported the presence of a flame in a roof cavity behind the shields.
No injuries were reported in the blasts at the operation, which was evacuated immediately after the initial explosion. There were 160 workers underground at the time of the blast.
Shoal Creek, a unionised mine that employs both room and pillar and longwall methods, employed about 850 people (700 underground) and produced almost 1.4 million tons in the first half of 2005.