Abstract: A supervisor at a concrete ready-mix plant assigned Employees #1 and #2 to determine why stone was not running from the holding bin. Upon examination they found that the bin contained approximately 75 tons of #4 ASTM stone and decided that it was probably frozen. The two employees entered a tunnel below the bins that contained the hoppers and conveyor. They tried unsuccessfully to loosen the stone by banging on the side of the hopper with a sledgehammer. They then went to the front of the bin, Employee #1 with the sledgehammer and Employee #2 with a 4 in. by 4 in. by 3/8 in. angle iron and a 10 ft long pry bar. They entered the bin and climbed on top of the stone, directly over the grate-covered hopper. The hopper gates were open and the conveyor belt was running (350 fpm). When Employees #1 and #2 succeeded in loosening the stone, it gave way beneath them. They were quickly drawn down into the flowing material. Employee #1 was buried entirely and Employee #2 was buried up to his chin. It took about 1 1/2 hours of digging with hand shovels to free both employees. Employee #1 died of asphyxia. Employee #2 was hospitalized for multiple bruises, contusions, and lacerations.