Abstract: Two employees of an excavating company were working in a 6.1-meter-long by 0.9-meter-wide by 1.8-meter-deep trench, installing a new sewer line. The owner of the company was nearby. The employees were installing the line under a sidewalk and street. They were digging laterally under the street curb and out into the street when they came to a concrete obstruction. They used a pneumatic jackhammer to break through the concrete, which contained a 13.2-kilovolt underground power line. They broke through the concrete and struck the power line. Both employees received electric shocks and were burned by the ensuing electric arc. One employee was electrocuted. The other sustained severe internal and external burns. The owner of the company went into the trench and was also electrocuted. A plumber had called the utility owners but had given the wrong address. In addition, the excavating company had not waited the full 3 days for a survey to be conducted of the site. The employees had not received any training.