An employee was driving a forklift to take excess liquid concrete to an area where it is poured into 2x2x6 forms for retaining wall blocks. The liquid concrete was being poured into a bucket, which the forklift was lifting above the forms, when the employee exited the forklift to either move or manipulate the bucket. The bucket slipped off the forklift onto his person, pinning him to the ground and causing body trauma.