Roof fall found by mine examiner during preshift in intersection in common entry 600-feet outby the faces of the active South Mains working section 100-feet outby spad 6619. Cave measured: 20? x 19.5? x 6? high. No evident roof defects. Primary roof support = 6 ? foot resin-assisted torque tension bolts (4?x 4? centers). Secondary support = 12-foot cable bolts (8? x 8? centers).