Abstract: At approximately 11:45 a.m. on August 4 2005, an employee of J.R. Construction was working on the vertical falsework for a concrete wall. He placed a ladder against the wood form and was checking the plumb line of the wall. He was standing about five feet up on the ladder to access the plumb line, string. A Merli concrete pump truck was parked on the street, about 110 feet away. The boom of the pump truck was extended across the jobsite to reach the wall, where the employee was working. He was on the north side of the wall, and the hosepipe from the truck approached from the south side. Back on the street, the left front outrigger of the truck suddenly sunk into the ground. The wood lagging placed under the outrigger pad broke and caved in. This caused the vehicle to rotate slightly and lean to the left. The end of the pipe lurched forward and came down hard on the top of the wood form, where the employee was working. The pipe crushed the top of the form and struck the employee in the face and knocked him from the ladder. The employee received injuries to his head, neck and spine and was transported to UCSD downtown Medical Center. He was hospitalized and treated for his injuries.