Abstract: At approximately 1:30 p.m. on June 28, 2012, Employee #1, a laborer, was working on a street maintenance project to dig a trench in a street in preparation for installation of electrical power. A Case backhoe machine with 1-ft bucket was removing concrete and dirt from the trench, which was approximately 35 to 40 inches deep, and dumping it into a truck. Employee #1 was in the trench, following the backhoe and using a shovel to remove any concrete and dirt debris from the trench. As Coworker #1, the backhoe operator, moved the backhoe bucket back to the trench lane, a large piece of concrete debris that was lodged in the bucket flew out laterally and struck Employee #1 in the arm. Employee #1 sustained a fracture of his right arm and was hospitalized for 4 days. This injury was reported to Cal/OSHA at 2:55 p.m. on June 28, 2012. According to the investigation report, neither Employee #1 nor Coworker #1 knew that the concrete debris was stuck in the bucket. Employee #1 said he was never under the backhoe or load and was 10 to 15 feet away from the backhoe. Coworker #1 said he also would check to see if Employee #1 was clear before moving the bucket back to the trench lane. Coworker #1 said Employee #1 was clear and was a good 20 feet from the machine. According to the employer, the concrete piece was about 8 in. by 12 in. by 12 in.