Abstract: On November 14, 1989, Employee #1 was the second in charge of a 4-man field crew that had been contracted to install a rail unloading conveyor system at an existing ready mix concrete plant. The crew was working over a large drive-over sand bin that was 15 1/2 ft deep by 40 ft long by 15 ft wide. This bin opened up into a smaller weigh hopper and conveyor. The grate over the top of the bin was made of widely spaced rails designed for bottom opening dump trucks to drive over and dump. The employees were working off the grate, with no floor covers. Employee #1 was making adjustments to the conveyor. At approximately 10:30 a.m., a coworker dropped a rope and then a section of the rail grate through the opening in the bin grate. Employee #1 went into the sand bin to retrieve the rail. He did not wear ppe--a safety belt, line, or harness. Employee #1 rode the headache ball of a RO Stinger 110-1 truck crane as it was lowered to the bottom gate of the sand bin through a small opening in the bin grate. He attached the rail to the crane line. As the rail was raised, the residual sand on the walls of the bin fell and completely engulfed Employee #1. He died of asphyxiation and inhalation of sand. The grate over the bin used as a work platform was not covered. The employees were allowed to enter bins to retrieve tools and materials by riding the headache ball, without using ppe. The employer had no procedures for entering bins or silos. The employees were not instructed in the site hazards. The bin could have been emptied of sand before the conveyor was installed.