Abstract: AN EMPLOYER WAS CONTRACTED TO DIG TWO CAISSONS FOR THE REPAIR OF AN UNDERGROUND TUNNEL COMPLEX CONTAINING A TOP SECRET COMMUNICATIONS CENTER. THE 36-INCH-DIAMETER CAISSONS WERE TO BE DUG TO A DEPTH OF ABOUT 20 FEET. AN EMPLOYEE WAS IN ONE OF THE CAISSONS THAT WAS 18 FEET DEEP. HE WAS WORKING WITHIN A 30-INCH-DIAMETER CASING THAT EXTENDED 8 FEET ABOVE THE GROUND (THE CASING WAS 26 FEET LONG). DEBRIS HAD BEEN ENCOUNTERED, AND THE EMPLOYEE HAD TO DIG AT THIS POINT BY HAND. THE EMPLOYEE WAS USING A SMALL JACKHAMMER (CALLED A CLAY SPADE). THE JACKHAMMER CONTACTED A 12-KILOVOLT UNDERGROUND POWER LINE, ELECTROCUTING THE EMPLOYEE. THE BLUEPRINTS FOR THE SITE DID NOT INDICATE THE PRESENCE OF THE UNDERGROUND LINES, AND THE OWNER DID NOT DISCLOSE THEIR PRESENCE TO THE CONTRACTOR. THE CONTRACTOR DID NOT HAVE A FORMAL SAFETY PROGRAM AND HAD ONLY AN INFORMAL TRAINING PROGRAM.