WHILE MEN WERE BEING TRANSPORTED TO THE SURFACE, THE MINE CAR ENCOUNTERED A PIECE OF FALLEN ROCK CAUSING THE FRONT END TO SHIFT & CONTACT A PIECE OF TIMBER WHICH STALLED THE HOIST & CAUSED HOIST ROPE TO TEAR. SLOPE CAR TRAVELED DOWN SLOPE 80-100 FT, WHERE THE BACK END DERAILED & CAME TO REST AGAINST THE RIB.