An employee had just rigged up a 3/4" thick plate (10'x 6') with a single hook chain. The chain was choked through a hole in the center of one edge of the plate. The employee was standing near the plate while an equipment operator was raising the plate with an excavator. The chain came loose, and the one edge of the plate that was 2.5" in the air came down on the employee's toes resulting in amputation of two toes.