The accident occurred on December 12 at the Pennsylvania mine when Eric Benjamin Hill, who had 11 years mining experience, was fatally injured when he was struck by a roof fall while operating the continuous mining machine by remote control in the last open crosscut intersection out by the face.

The fallen roof material, which had been permanently supported, was a horseback (drag fold) approximately 25ft by 16ft at its base and ranging 0-4 feet thick.

MSHA issued the following best practices:

Make frequent roof examinations and be alert to changing roof conditions at all times – Slickensided shale may indicate the presence of roof hazards, such as horsebacks or kettle bottoms;

Know and follow the approved roof control plan;

Install and examine test holes frequently to detect changes in roof strata;

Install adequate, additional roof support when adverse conditions are encountered or anticipated; and

Train all miners on the importance of roof examinations.