An employee was carrying trash outside to the burning pit using a forklift. The forklift got stuck in the mud outside and the operator asked another forklift operator to pull the stuck forklift out of the mud. The second forklift was backing up to the stuck forklift to attach a chain. The injured employee was holding the chain and while the second forklift backed up and the employee's left arm was crushed between the two forklifts resulting in amputation of the arm.