Abstract: At approximately 2:00 p.m. on June 22, 1991, Employee #1 was monitoring a grout pump. A forklift truck drove next to the pump and raised a hopper full of grout that was to be transferred into the pump through an approximately 1 ft in diameter by 3 ft long flexible hose. The forklift raised the hopper about 8 = ft above the pump opening to facilitate continuous flow. When the hopper was nearly empty, the forklift operator raised the hopper another 4 in. and then abruptly dropped it to its original height to shake out the last bit of grout. He also tilted the forks of the truck to remove residual grout from them. As the operator tilted the forks, the hopper slipped and fell on the pump, pinning Employee #1's right arm. He suffered a compound fracture, for which he was hospitalized.