Abstract: At approximately 8:20 a.m. on April 18, 1988, Employee #1, a carpenter, was operating a 225 ton capacity Manitowoc 4100W crane, serial #41364, at a sewage treatment plant under construction. The crane was located just south of clarifier #8 and was being used to move 200 lb scaffold bucks from clarifier #7 to clarifier #6. The crane had 220 ft of boom, with a 60 ft jib on the end. The foreman was standing on the northwest side of clarifier #8, where he could see the employee and could see down into clarifier #6, where the scaffold bucks were being set. The four lifts had been over the front of the crane and the fifth lift was to be on the crane's right and over the side. The employee was lowering the fifth lift when the back of the crane came up. He tried to pull back on the boom but it had gone too far down and the west side draped across clarifier #8. When Employee #1 saw that he had lost the load, he stood. The counterweights tore loose from the rear of the crane, causing Employee #1 to fall to the ground. He suffered hip injuries and a collapsed lung, for which he was hospitalized. In the opinion of the OSHA inspector, this accident was the result of human error. The employee had 30 years experience as a crane operator and should have realized that he was over the side of the crane on the last lift. He could have repositioned the tracks so that the fifth lift was over the front like the first four. A load limit chart, signal chart, and boom angle indicator were accessible to the operator and were all in good condition. Because the employee could not see clarifier #6, he may have been too intent on observing his foreman giving him directions and not realized he was over the side.