THE ALLEGED INJURY WAS TO HAVE OCCURRED WHILE THE EE & HIS HELPER WERE IN THE PROCESS OF INSTALLING TIMBERS & COLLARS. AS THE EE WAS IN THE PROCESS OF SETTING TIMBERS, AN UNDETECTED PIECE OF D RAW ROCK FELL FROM BETWEEN PERMANENT SUPPORTS IMPACTING THE EE ON TOP OF HIS HARD HAT. THE ROCK MEASURED 24"" X 17"" X 0-8"" THICK & THE OVERALL HEIGHT OF THE AREA WAS 8'4"" HIGH & EE'S APPROXIMA