UNITED STATES
DEPARTMENT OF LABOR

At approximately 11:30 a.m. on July 28, 2009, Employee #1 and two coworkers were digging with an excavator when the machine contacted something in the excavation that caused a loud explosion and produced a bright flash. This first explosion occurred because a 12,000 underground power line was contacted with the excavator's metal bucket. There were no injuries. Employee #3, the excavator operator, referred to two sets of plans to determine what he had contacted with the excavator. The electrical power was lost to two administrative buildings nearby. Employee #3 made a call to the high voltage underground utility contractor to determine what was encountered to cause the first explosion. Employee #2 was called to the scene by Employee #3. Employee #1 and Employee #2 recalled that Employee #3 asking Employee #2 to determine whether or not the explosion area was still electrically energized. Employee #2 was not told by Employee #3 that an explosion had already occurred before his arrival to the area. At 11:30 a.m. a second explosion occurred with a similar sound and bright flash. According to Employee #3, he ordered Employee #1 to use a 4-ft 10-in. long shovel with a steel spade and wooden handles to move dirt to view what caused the first explosion. Employee #1 unknowingly contacted the same 12,000-volt line with the steel spade. Employee #2 was inside the excavation with a noncontact electric voltage detector (Greenlee Model Number GT-11 50-1,000-volts) to determine if there was any electrically energized equipment to cause the 1st explosion. The second explosion caused burn injuries to Employee #1, Employee #2, and Employee #3 with the most severe injuries to Employee #1. Employee #2 and Employee #3 received minor burns, were treated and released from local hospitals on the same day. Employee #1 received burns to the face and an inhalation injury and was subsequently hospitalized for two nights.