EE & COWORKER WERE PERFORMING WORK NEAR #5 BELT LINE. AT #42 BREAK WHEN HE NOTICED A 24"" LONG X18"" WIDE X3"" THICK ROCK HANGING DOWN NEAR THE CONTROL LINE. AWAY FROM THE ROCK. THE ROCK FELL PINCHING HIS HAND BETWEEN THE ROCK & BELT STRUCTURE.DEGREE 3 CLASS O7